Add new feature UBLK_F_BATCH_IO which replaces the following two
per-io commands:
- UBLK_U_IO_FETCH_REQ
- UBLK_U_IO_COMMIT_AND_FETCH_REQ
with three per-queue batch io uring_cmd:
- UBLK_U_IO_PREP_IO_CMDS
- UBLK_U_IO_COMMIT_IO_CMDS
- UBLK_U_IO_FETCH_IO_CMDS
Then ublk can deliver batch io commands to ublk server in single
multishort uring_cmd, also allows to prepare & commit multiple
commands in batch style via single uring_cmd, communication cost is
reduced a lot.
This feature also doesn't limit task context any more for all supported
commands, so any allowed uring_cmd can be issued in any task context.
ublk server implementation becomes much easier.
Meantime load balance becomes much easier to support with this feature.
The command `UBLK_U_IO_FETCH_IO_CMDS` can be issued from multiple task
contexts, so each task can adjust this command's buffer length or number
of inflight commands for controlling how much load is handled by current
task.
Later, priority parameter will be added to command `UBLK_U_IO_FETCH_IO_CMDS`
for improving load balance support.
UBLK_U_IO_NEED_GET_DATA isn't supported in batch io yet, but it may be
enabled in future via its batch pair.
Reviewed-by: Caleb Sander Mateos <csander@purestorage.com>
Signed-off-by: Ming Lei <ming.lei@redhat.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
In case of BATCH_IO, any request filled in event kfifo, they don't get
chance to be dispatched any more when releasing ublk char device, so
we have to abort them too.
Add ublk_abort_batch_queue() for aborting this kind of requests.
Reviewed-by: Caleb Sander Mateos <csander@purestorage.com>
Signed-off-by: Ming Lei <ming.lei@redhat.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
Extract common request preparation and cancellation logic into
__ublk_queue_rq_common() helper function. Add dedicated
ublk_batch_queue_rq() for batch mode operations to eliminate runtime check
in ublk_queue_rq().
Signed-off-by: Ming Lei <ming.lei@redhat.com>
Reviewed-by: Caleb Sander Mateos <csander@purestorage.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
Add UBLK_U_IO_FETCH_IO_CMDS command to enable efficient batch processing
of I/O requests. This multishot uring_cmd allows the ublk server to fetch
multiple I/O commands in a single operation, significantly reducing
submission overhead compared to individual FETCH_REQ* commands.
Key Design Features:
1. Multishot Operation: One UBLK_U_IO_FETCH_IO_CMDS can fetch many I/O
commands, with the batch size limited by the provided buffer length.
2. Dynamic Load Balancing: Multiple fetch commands can be submitted
simultaneously, but only one is active at any time. This enables
efficient load distribution across multiple server task contexts.
3. Implicit State Management: The implementation uses three key variables
to track state:
- evts_fifo: Queue of request tags awaiting processing
- fcmd_head: List of available fetch commands
- active_fcmd: Currently active fetch command (NULL = none active)
States are derived implicitly:
- IDLE: No fetch commands available
- READY: Fetch commands available, none active
- ACTIVE: One fetch command processing events
4. Lockless Reader Optimization: The active fetch command can read from
evts_fifo without locking (single reader guarantee), while writers
(ublk_queue_rq/ublk_queue_rqs) use evts_lock protection. The memory
barrier pairing plays key role for the single lockless reader
optimization.
Implementation Details:
- ublk_queue_rq() and ublk_queue_rqs() save request tags to evts_fifo
- __ublk_acquire_fcmd() selects an available fetch command when
events arrive and no command is currently active
- ublk_batch_dispatch() moves tags from evts_fifo to the fetch command's
buffer and posts completion via io_uring_mshot_cmd_post_cqe()
- State transitions are coordinated via evts_lock to maintain consistency
Reviewed-by: Caleb Sander Mateos <csander@purestorage.com>
Signed-off-by: Ming Lei <ming.lei@redhat.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
Add infrastructure for delivering I/O commands to ublk server in batches,
preparing for the upcoming UBLK_U_IO_FETCH_IO_CMDS feature.
Key components:
- struct ublk_batch_fetch_cmd: Represents a batch fetch uring_cmd that will
receive multiple I/O tags in a single operation, using io_uring's
multishot command for efficient ublk IO delivery.
- ublk_batch_dispatch(): Batch version of ublk_dispatch_req() that:
* Pulls multiple request tags from the events FIFO (lock-free reader)
* Prepares each I/O for delivery (including auto buffer registration)
* Delivers tags to userspace via single uring_cmd notification
* Handles partial failures by restoring undelivered tags to FIFO
The batch approach significantly reduces notification overhead by aggregating
multiple I/O completions into single uring_cmd, while maintaining the same
I/O processing semantics as individual operations.
Error handling ensures system consistency: if buffer selection or CQE
posting fails, undelivered tags are restored to the FIFO for retry,
meantime IO state has to be restored.
This runs in task work context, scheduled via io_uring_cmd_complete_in_task()
or called directly from ->uring_cmd(), enabling efficient batch processing
without blocking the I/O submission path.
Reviewed-by: Caleb Sander Mateos <csander@purestorage.com>
Signed-off-by: Ming Lei <ming.lei@redhat.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
Add ublk io events fifo structure and prepare for supporting command
batch, which will use io_uring multishot uring_cmd for fetching one
batch of io commands each time.
One nice feature of kfifo is to allow multiple producer vs single
consumer. We just need lock the producer side, meantime the single
consumer can be lockless.
The producer is actually from ublk_queue_rq() or ublk_queue_rqs(), so
lock contention can be eased by setting proper blk-mq nr_queues.
Reviewed-by: Caleb Sander Mateos <csander@purestorage.com>
Signed-off-by: Ming Lei <ming.lei@redhat.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
Handle UBLK_U_IO_COMMIT_IO_CMDS by walking the uring_cmd fixed buffer:
- read each element into one temp buffer in batch style
- parse and apply each element for committing io result
Reviewed-by: Caleb Sander Mateos <csander@purestorage.com>
Signed-off-by: Ming Lei <ming.lei@redhat.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
This commit implements the handling of the UBLK_U_IO_PREP_IO_CMDS command,
which allows userspace to prepare a batch of I/O requests.
The core of this change is the `ublk_walk_cmd_buf` function, which iterates
over the elements in the uring_cmd fixed buffer. For each element, it parses
the I/O details, finds the corresponding `ublk_io` structure, and prepares it
for future dispatch.
Add per-io lock for protecting concurrent delivery and committing.
Reviewed-by: Caleb Sander Mateos <csander@purestorage.com>
Signed-off-by: Ming Lei <ming.lei@redhat.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
Add new command UBLK_U_IO_PREP_IO_CMDS, which is the batch version of
UBLK_IO_FETCH_REQ.
Add new command UBLK_U_IO_COMMIT_IO_CMDS, which is for committing io command
result only, still the batch version.
The new command header type is `struct ublk_batch_io`.
This patch doesn't actually implement these commands yet, just validates the
SQE fields.
Reviewed-by: Caleb Sander Mateos <csander@purestorage.com>
Signed-off-by: Ming Lei <ming.lei@redhat.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
batch io is designed to be independent of task context, and we will not
track task context for batch io feature.
Reviewed-by: Caleb Sander Mateos <csander@purestorage.com>
Signed-off-by: Ming Lei <ming.lei@redhat.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
Introduces the basic structure for a batched I/O feature in the ublk driver.
It adds placeholder functions and a new file operations structure,
ublk_ch_batch_io_fops, which will be used for fetching and committing I/O
commands in batches. Currently, the feature is disabled.
Reviewed-by: Caleb Sander Mateos <csander@purestorage.com>
Signed-off-by: Ming Lei <ming.lei@redhat.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
When ublksrv runs inside a pid namespace, START/END_RECOVERY compared
the stored init-ns tgid against the userspace pid (getpid vnr), so the
check failed and control ops could not proceed. Compare against the
caller’s init-ns tgid and store that value, then translate it back to
the caller’s pid namespace when reporting GET_DEV_INFO so ublk list
shows a sensible pid.
Testing: start/recover in a pid namespace; `ublk list` shows
reasonable pid values in init, child, and sibling namespaces.
Fixes: c2c8089f32 ("ublk: validate ublk server pid")
Signed-off-by: Seamus Connor <sconnor@purestorage.com>
Reviewed-by: Caleb Sander Mateos <csander@purestorage.com>
Reviewed-by: Ming Lei <ming.lei@redhat.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
Patch series "Add ARRAY_END(), and use it to fix off-by-one bugs", v6.
Add ARRAY_END(), and use it to fix off-by-one bugs
ARRAY_END() is a macro to calculate a pointer to one past the last element
of an array argument. This is a very common pointer, which is used to
iterate over all elements of an array:
for (T *p = a; p < ARRAY_END(a); p++)
...
Of course, this pointer should never be dereferenced. A pointer one past
the last element of an array should not be dereferenced; it's perfectly
fine to hold such a pointer --and a good thing to do--, but the only thing
it should be used for is comparing it with other pointers derived from the
same array.
Due to how special these pointers are, it would be good to use consistent
naming. It's common to name such a pointer 'end' --in fact, we have many
such cases in the kernel--. C++ even standardized this name with
std::end(). Let's try naming such pointers 'end', and try also avoid
using 'end' for pointers that are not the result of ARRAY_END().
It has been incorrectly suggested that these pointers are dangerous, and
that they should never be used, suggesting to use something like
#define ARRAY_LAST(a) ((a) + ARRAY_SIZE(a) - 1)
for (T *p = a; p <= ARRAY_LAST(a); p++)
...
This is bogus, as it doesn't scale down to arrays of 0 elements. In the
case of an array of 0 elements, ARRAY_LAST() would underflow the pointer,
which not only it can't be dereferenced, it can't even be held (it
produces Undefined Behavior). That would be a footgun. Such arrays don't
exist per the ISO C standard; however, GCC supports them as an extension
(with partial support, though; GCC has a few bugs which need to be fixed).
This patch set fixes a few places where it was intended to use the array
end (that is, one past the last element), but accidentally a pointer to
the last element was used instead, thus wasting one byte.
It also replaces other places where the array end was correctly calculated
with ARRAY_SIZE(), by using the simpler ARRAY_END().
Also, there was one drivers/ file that already defined this macro. We
remove that definition, to not conflict with this one.
This patch (of 4):
ARRAY_END() returns a pointer one past the end of the last element in the
array argument. This pointer is useful for iterating over the elements of
an array:
for (T *p = a, p < ARRAY_END(a); p++)
...
Link: https://lkml.kernel.org/r/cover.1765449750.git.alx@kernel.org
Link: https://lkml.kernel.org/r/5973cfb674192bc8e533485dbfb54e3062896be1.1765449750.git.alx@kernel.org
Signed-off-by: Alejandro Colomar <alx@kernel.org>
Cc: Kees Cook <kees@kernel.org>
Cc: Christopher Bazley <chris.bazley.wg14@gmail.com>
Cc: Rasmus Villemoes <linux@rasmusvillemoes.dk>
Cc: Marco Elver <elver@google.com>
Cc: Michal Hocko <mhocko@suse.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Al Viro <viro@zeniv.linux.org.uk>
Cc: Alexander Potapenko <glider@google.com>
Cc: Dmitriy Vyukov <dvyukov@google.com>
Cc: Jann Horn <jannh@google.com>
Cc: Maciej W. Rozycki <macro@orcam.me.uk>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
The KMSG_COMPONENT macro is a leftover of the s390 specific "kernel
message catalog" from 2008 [1] which never made it upstream.
The macro was added to s390 code to allow for an out-of-tree patch which
used this to generate unique message ids. Also this out-of-tree doesn't
exist anymore.
The pattern of how the KMSG_COMPONENT is used was partially also used for
non s390 specific code, for whatever reasons.
Remove the macro in order to get rid of a pointless indirection.
Link: https://lkml.kernel.org/r/20251126143602.2207435-1-hca@linux.ibm.com
Link: https://lwn.net/Articles/292650/ [1]
Signed-off-by: Heiko Carstens <hca@linux.ibm.com>
Reviewed-by: Sergey Senozhatsky <senozhatsky@chromium.org>
Cc: Jens Axboe <axboe@kernel.dk>
Cc: Minchan Kim <minchan@kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
pp_in_progress makes sure that only one post-processing (writeback or
recomrpession) is active at any given time. Functionality wise it,
basically, shadows zram init_lock, when init_lock is acquired in writer
mode.
Switch recompress_store() and writeback_store() to take zram init_lock in
writer mode, like all store() sysfs handlers should do, so that we can
drop pp_in_progress. Recompression and writeback can be somewhat slow, so
holding init_lock in writer mode can block zram attrs reads, but in
reality the only zram attrs reads that take place are mm_stat reads, and
usually it's the same process that reads mm_stat and does recompression or
writeback.
Link: https://lkml.kernel.org/r/20251216071342.687993-1-senozhatsky@chromium.org
Signed-off-by: Sergey Senozhatsky <senozhatsky@chromium.org>
Suggested-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Cc: Brian Geffon <bgeffon@google.com>
Cc: Minchan Kim <minchan@kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
ac_time is now in seconds, do not use ktime_to_timespec64()
[akpm@linux-foundation.org: remove now-unused local `ts']
[akpm@linux-foundation.org: fix build]
Link: https://lkml.kernel.org/r/20260115033031.3818977-1-senozhatsky@chromium.org
Signed-off-by: Sergey Senozhatsky <senozhatsky@chromium.org>
Reported-by: Chris Mason <clm@meta.com>
Closes: https://lkml.kernel.org/r/20260114124522.1326519-1-clm@meta.com
Cc: Brian Geffon <bgeffon@google.com>
Cc: David Stevens <stevensd@google.com>
Cc: Minchan Kim <minchan@google.com>
Cc: Richard Chang <richardycc@google.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
A minor fixup of 80-cols breakage in recompress_slot() comment and
zs_malloc() call.
Link: https://lkml.kernel.org/r/ff3254847dbdc6fbd2e3fed53c572a261d60b7b6.1765775954.git.senozhatsky@chromium.org
Signed-off-by: Sergey Senozhatsky <senozhatsky@chromium.org>
Cc: Brian Geffon <bgeffon@google.com>
Cc: David Stevens <stevensd@google.com>
Cc: Minchan Kim <minchan@google.com>
Cc: Richard Chang <richardycc@google.com>
Cc: Chris Mason <clm@meta.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
We have a somewhat confusing internal API naming. E.g. the following
code:
zram_slot_lock()
if (zram_allocated())
zram_set_flag()
zram_slot_unlock()
may look like it does something on zram device level, but in fact it tests
and sets slot entry flags, not the device ones.
Rename API to explicitly distinguish functions that operate on the slot
level from functions that operate on the zram device level.
While at it, fixup some coding styles.
[senozhatsky@chromium.org: fix up mark_slot_accessed()]
Link: https://lkml.kernel.org/r/20260115031922.3813659-1-senozhatsky@chromium.org
Link: https://lkml.kernel.org/r/775a0b1a0ace5caf1f05965d8bc637c1192820fa.1765775954.git.senozhatsky@chromium.org
Signed-off-by: Sergey Senozhatsky <senozhatsky@chromium.org>
Cc: Brian Geffon <bgeffon@google.com>
Cc: David Stevens <stevensd@google.com>
Cc: Minchan Kim <minchan@google.com>
Cc: Richard Chang <richardycc@google.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
We can reduce sizeof(zram_table_entry) on 64-bit systems by converting
flags and ac_time to u32. Entry flags fit into u32, and for ac_time u32
gives us over a century of entry lifespan (approx 136 years) which is
plenty (zram uses system boot time (seconds)).
In struct zram_table_entry we use bytes aliasing, because bit-wait API
(for slot lock) requires a whole unsigned long word.
Link: https://lkml.kernel.org/r/d7c0b48450c70eeb5fd8acd6ecd23593f30dbf1f.1765775954.git.senozhatsky@chromium.org
Signed-off-by: Sergey Senozhatsky <senozhatsky@chromium.org>
Suggested-by: David Stevens <stevensd@google.com>
Cc: Brian Geffon <bgeffon@google.com>
Cc: Minchan Kim <minchan@google.com>
Cc: Richard Chang <richardycc@google.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Do not spread device attributes declarations across the file, move
io_stat, mm_stat, debug_stat to a common device-attr section.
Link: https://lkml.kernel.org/r/20251201094754.4149975-8-senozhatsky@chromium.org
Signed-off-by: Sergey Senozhatsky <senozhatsky@chromium.org>
Cc: Brian Geffon <bgeffon@google.com>
Cc: David Stevens <stevensd@google.com>
Cc: Minchan Kim <minchan@google.com>
Cc: Richard Chang <richardycc@google.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Use init_lock guard() in sysfs store/show handlers, in order to simplify
and, more importantly, to modernize the code.
While at it, fix up more coding styles.
Link: https://lkml.kernel.org/r/20251201094754.4149975-7-senozhatsky@chromium.org
Signed-off-by: Sergey Senozhatsky <senozhatsky@chromium.org>
Cc: Brian Geffon <bgeffon@google.com>
Cc: David Stevens <stevensd@google.com>
Cc: Minchan Kim <minchan@google.com>
Cc: Richard Chang <richardycc@google.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
We don't free page in zram_free_page(), not all slots even have any memory
associated with them (e.g. ZRAM_SAME). We free the slot (or reset it),
rename the function accordingly.
Link: https://lkml.kernel.org/r/20251201094754.4149975-6-senozhatsky@chromium.org
Signed-off-by: Sergey Senozhatsky <senozhatsky@chromium.org>
Cc: Brian Geffon <bgeffon@google.com>
Cc: David Stevens <stevensd@google.com>
Cc: Minchan Kim <minchan@google.com>
Cc: Richard Chang <richardycc@google.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Move bd_stat function and attribute declaration to
existing CONFIG_WRITEBACK ifdef-sections.
Link: https://lkml.kernel.org/r/20251201094754.4149975-5-senozhatsky@chromium.org
Signed-off-by: Sergey Senozhatsky <senozhatsky@chromium.org>
Cc: Brian Geffon <bgeffon@google.com>
Cc: David Stevens <stevensd@google.com>
Cc: Minchan Kim <minchan@google.com>
Cc: Richard Chang <richardycc@google.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Patch series "zram: introduce compressed data writeback", v2.
As writeback becomes more common there is another shortcoming that needs
to be addressed - compressed data writeback. Currently zram does
uncompressed data writeback which is not optimal due to potential CPU and
battery wastage. This series changes suboptimal uncompressed writeback to
a more optimal compressed data writeback.
This patch (of 7):
zram stores all written back slots raw, which implies that during
writeback zram first has to decompress slots (except for ZRAM_HUGE slots,
which are raw already). The problem with this approach is that not every
written back page gets read back (either via read() or via page-fault),
which means that zram basically wastes CPU cycles and battery
decompressing such slots. This changes with introduction of decompression
on demand, in other words decompression on read()/page-fault.
One caveat of decompression on demand is that async read is completed in
IRQ context, while zram decompression is sleepable. To workaround this,
read-back decompression is offloaded to a preemptible context - system
high-prio work-queue.
At this point compressed writeback is still disabled, a follow up patch
will introduce a new device attribute which will make it possible to
toggle compressed writeback per-device.
[senozhatsky@chromium.org: rewrote original implementation]
Link: https://lkml.kernel.org/r/20251201094754.4149975-1-senozhatsky@chromium.org
Link: https://lkml.kernel.org/r/20251201094754.4149975-2-senozhatsky@chromium.org
Signed-off-by: Richard Chang <richardycc@google.com>
Co-developed-by: Sergey Senozhatsky <senozhatsky@chromium.org>
Suggested-by: Minchan Kim <minchan@google.com>
Suggested-by: Brian Geffon <bgeffon@google.com>
Cc: David Stevens <stevensd@google.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
-----BEGIN PGP SIGNATURE-----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=8QRq
-----END PGP SIGNATURE-----
Merge tag 'block-6.19-20260116' of git://git.kernel.org/pub/scm/linux/kernel/git/axboe/linux
Pull block fixes from Jens Axboe:
- NVMe pull request via Keith:
- Device quirk to disable faulty temperature (Ilikara)
- TCP target null pointer fix from bad host protocol usage (Shivam)
- Add apple,t8103-nvme-ans2 as a compatible apple controller
(Janne)
- FC tagset leak fix (Chaitanya)
- TCP socket deadlock fix (Hannes)
- Target name buffer overrun fix (Shin'ichiro)
- Fix for an underflow for rnbd during device unmap
- Zero the non-PI part of the auto integrity buffer
- Fix for a configfs memory leak in the null block driver
* tag 'block-6.19-20260116' of git://git.kernel.org/pub/scm/linux/kernel/git/axboe/linux:
rnbd-clt: fix refcount underflow in device unmap path
nvme: fix PCIe subsystem reset controller state transition
nvmet: do not copy beyond sybsysnqn string length
nvmet-tcp: fixup hang in nvmet_tcp_listen_data_ready()
null_blk: fix kmemleak by releasing references to fault configfs items
block: zero non-PI portion of auto integrity buffer
nvme-fc: release admin tagset if init fails
nvme-apple: add "apple,t8103-nvme-ans2" as compatible
nvme-tcp: fix NULL pointer dereferences in nvmet_tcp_build_pdu_iovec
nvme-pci: disable secondary temp for Wodposit WPBSNM8
During device unmapping (triggered by module unload or explicit unmap),
a refcount underflow occurs causing a use-after-free warning:
[14747.574913] ------------[ cut here ]------------
[14747.574916] refcount_t: underflow; use-after-free.
[14747.574917] WARNING: lib/refcount.c:28 at refcount_warn_saturate+0x55/0x90, CPU#9: kworker/9:1/378
[14747.574924] Modules linked in: rnbd_client(-) rtrs_client rnbd_server rtrs_server rtrs_core ...
[14747.574998] CPU: 9 UID: 0 PID: 378 Comm: kworker/9:1 Tainted: G O N 6.19.0-rc3lblk-fnext+ #42 PREEMPT(voluntary)
[14747.575005] Workqueue: rnbd_clt_wq unmap_device_work [rnbd_client]
[14747.575010] RIP: 0010:refcount_warn_saturate+0x55/0x90
[14747.575037] Call Trace:
[14747.575038] <TASK>
[14747.575038] rnbd_clt_unmap_device+0x170/0x1d0 [rnbd_client]
[14747.575044] process_one_work+0x211/0x600
[14747.575052] worker_thread+0x184/0x330
[14747.575055] ? __pfx_worker_thread+0x10/0x10
[14747.575058] kthread+0x10d/0x250
[14747.575062] ? __pfx_kthread+0x10/0x10
[14747.575066] ret_from_fork+0x319/0x390
[14747.575069] ? __pfx_kthread+0x10/0x10
[14747.575072] ret_from_fork_asm+0x1a/0x30
[14747.575083] </TASK>
[14747.575096] ---[ end trace 0000000000000000 ]---
Befor this patch :-
The bug is a double kobject_put() on dev->kobj during device cleanup.
Kobject Lifecycle:
kobject_init_and_add() sets kobj.kref = 1 (initialization)
kobject_put() sets kobj.kref = 0 (should be called once)
* Before this patch:
rnbd_clt_unmap_device()
rnbd_destroy_sysfs()
kobject_del(&dev->kobj) [remove from sysfs]
kobject_put(&dev->kobj) PUT #1 (WRONG!)
kref: 1 to 0
rnbd_dev_release()
kfree(dev) [DEVICE FREED!]
rnbd_destroy_gen_disk() [use-after-free!]
rnbd_clt_put_dev()
refcount_dec_and_test(&dev->refcount)
kobject_put(&dev->kobj) PUT #2 (UNDERFLOW!)
kref: 0 to -1 [WARNING!]
The first kobject_put() in rnbd_destroy_sysfs() prematurely frees the
device via rnbd_dev_release(), then the second kobject_put() in
rnbd_clt_put_dev() causes refcount underflow.
* After this patch :-
Remove kobject_put() from rnbd_destroy_sysfs(). This function should
only remove sysfs visibility (kobject_del), not manage object lifetime.
Call Graph (FIXED):
rnbd_clt_unmap_device()
rnbd_destroy_sysfs()
kobject_del(&dev->kobj) [remove from sysfs only]
[kref unchanged: 1]
rnbd_destroy_gen_disk() [device still valid]
rnbd_clt_put_dev()
refcount_dec_and_test(&dev->refcount)
kobject_put(&dev->kobj) ONLY PUT (CORRECT!)
kref: 1 to 0 [BALANCED]
rnbd_dev_release()
kfree(dev) [CLEAN DESTRUCTION]
This follows the kernel pattern where sysfs removal (kobject_del) is
separate from object destruction (kobject_put).
Fixes: 581cf833ca ("block: rnbd: add .release to rnbd_dev_ktype")
Signed-off-by: Chaitanya Kulkarni <ckulkarnilinux@gmail.com>
Acked-by: Jack Wang <jinpu.wang@ionos.com>
Reviewed-by: Jack Wang <jinpu.wang@ionos.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
When CONFIG_BLK_DEV_NULL_BLK_FAULT_INJECTION is enabled, the null-blk
driver sets up fault injection support by creating the timeout_inject,
requeue_inject, and init_hctx_fault_inject configfs items as children
of the top-level nullbX configfs group.
However, when the nullbX device is removed, the references taken to
these fault-config configfs items are not released. As a result,
kmemleak reports a memory leak, for example:
unreferenced object 0xc00000021ff25c40 (size 32):
comm "mkdir", pid 10665, jiffies 4322121578
hex dump (first 32 bytes):
69 6e 69 74 5f 68 63 74 78 5f 66 61 75 6c 74 5f init_hctx_fault_
69 6e 6a 65 63 74 00 88 00 00 00 00 00 00 00 00 inject..........
backtrace (crc 1a018c86):
__kmalloc_node_track_caller_noprof+0x494/0xbd8
kvasprintf+0x74/0xf4
config_item_set_name+0xf0/0x104
config_group_init_type_name+0x48/0xfc
fault_config_init+0x48/0xf0
0xc0080000180559e4
configfs_mkdir+0x304/0x814
vfs_mkdir+0x49c/0x604
do_mkdirat+0x314/0x3d0
sys_mkdir+0xa0/0xd8
system_call_exception+0x1b0/0x4f0
system_call_vectored_common+0x15c/0x2ec
Fix this by explicitly releasing the references to the fault-config
configfs items when dropping the reference to the top-level nullbX
configfs group.
Cc: stable@vger.kernel.org
Reviewed-by: Chaitanya Kulkarni <kch@nvidia.com>
Fixes: bb4c19e030 ("block: null_blk: make fault-injection dynamically configurable per device")
Signed-off-by: Nilay Shroff <nilay@linux.ibm.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
Add a best-effort stop command, UBLK_CMD_TRY_STOP_DEV, which only stops a
ublk device when it has no active openers.
Unlike UBLK_CMD_STOP_DEV, this command does not disrupt existing users.
New opens are blocked only after disk_openers has reached zero; if the
device is busy, the command returns -EBUSY and leaves it running.
The ub->block_open flag is used only to close a race with an in-progress
open and does not otherwise change open behavior.
Advertise support via the UBLK_F_SAFE_STOP_DEV feature flag.
Signed-off-by: Yoav Cohen <yoav@nvidia.com>
Reviewed-by: Ming Lei <ming.lei@redhat.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
This function always returns 0, so there is no need to return a value.
Signed-off-by: Yoav Cohen <yoav@nvidia.com>
Reviewed-by: Ming Lei <ming.lei@redhat.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
ublk user copy syscalls may be issued from any task, so they take a
reference count on the struct ublk_io to check whether it is owned by
the ublk server and prevent a concurrent UBLK_IO_COMMIT_AND_FETCH_REQ
from completing the request. However, if the user copy syscall is issued
on the io's daemon task, a concurrent UBLK_IO_COMMIT_AND_FETCH_REQ isn't
possible, so the atomic reference count dance is unnecessary. Check for
UBLK_IO_FLAG_OWNED_BY_SRV to ensure the request is dispatched to the
sever and obtain the request from ublk_io's req field instead of looking
it up on the tagset. Skip the reference count increment and decrement.
Commit 8a8fe42d76 ("ublk: optimize UBLK_IO_REGISTER_IO_BUF on daemon
task") made an analogous optimization for ublk zero copy buffer
registration.
Signed-off-by: Caleb Sander Mateos <csander@purestorage.com>
Reviewed-by: Ming Lei <ming.lei@redhat.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
Now that all the components of the ublk integrity feature have been
implemented, add UBLK_F_INTEGRITY to UBLK_F_ALL, conditional on block
layer integrity support (CONFIG_BLK_DEV_INTEGRITY). This allows ublk
servers to create ublk devices with UBLK_F_INTEGRITY set and
UBLK_U_CMD_GET_FEATURES to report the feature as supported.
Signed-off-by: Stanley Zhang <stazhang@purestorage.com>
[csander: make feature conditional on CONFIG_BLK_DEV_INTEGRITY]
Signed-off-by: Caleb Sander Mateos <csander@purestorage.com>
Reviewed-by: Ming Lei <ming.lei@redhat.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
Add a function ublk_copy_user_integrity() to copy integrity information
between a request and a user iov_iter. This mirrors the existing
ublk_copy_user_pages() but operates on request integrity data instead of
regular data. Check UBLKSRV_IO_INTEGRITY_FLAG in iocb->ki_pos in
ublk_user_copy() to choose between copying data or integrity data.
[csander: change offset units from data bytes to integrity data bytes,
fix CONFIG_BLK_DEV_INTEGRITY=n build, rebase on user copy refactor]
Signed-off-by: Stanley Zhang <stazhang@purestorage.com>
Signed-off-by: Caleb Sander Mateos <csander@purestorage.com>
Reviewed-by: Ming Lei <ming.lei@redhat.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
__ublk_check_and_get_req() checks that the passed in offset is within
the data length of the specified ublk request. However, only user copy
(ublk_check_and_get_req()) supports accessing ublk request data at a
nonzero offset. Zero-copy buffer registration (ublk_register_io_buf())
always passes 0 for the offset, so the check is unnecessary. Move the
check from __ublk_check_and_get_req() to ublk_check_and_get_req().
Signed-off-by: Caleb Sander Mateos <csander@purestorage.com>
Reviewed-by: Ming Lei <ming.lei@redhat.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
ublk_check_and_get_req() has a single callsite in ublk_user_copy(). It
takes a ton of arguments in order to pass local variables from
ublk_user_copy() to ublk_check_and_get_req() and vice versa. And more
are about to be added. Combine the functions to reduce the argument
passing noise.
Signed-off-by: Caleb Sander Mateos <csander@purestorage.com>
Reviewed-by: Ming Lei <ming.lei@redhat.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
ublk_ch_read_iter() and ublk_ch_write_iter() are nearly identical except
for the iter direction. Split out a helper function ublk_user_copy() to
reduce the code duplication as these functions are about to get larger.
Signed-off-by: Caleb Sander Mateos <csander@purestorage.com>
Reviewed-by: Ming Lei <ming.lei@redhat.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
Factor a helper function ublk_copy_user_bvec() out of
ublk_copy_user_pages(). It will be used for copying integrity data too.
Signed-off-by: Caleb Sander Mateos <csander@purestorage.com>
Reviewed-by: Ming Lei <ming.lei@redhat.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
Indicate to the ublk server when an incoming request has integrity data
by setting UBLK_IO_F_INTEGRITY in the ublksrv_io_desc's op_flags field.
Signed-off-by: Caleb Sander Mateos <csander@purestorage.com>
Reviewed-by: Ming Lei <ming.lei@redhat.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
Add a feature flag UBLK_F_INTEGRITY for a ublk server to request
integrity/metadata support when creating a ublk device. The ublk server
can also check for the feature flag on the created device or the result
of UBLK_U_CMD_GET_FEATURES to tell if the ublk driver supports it.
UBLK_F_INTEGRITY requires UBLK_F_USER_COPY, as user copy is the only
data copy mode initially supported for integrity data.
Add UBLK_PARAM_TYPE_INTEGRITY and struct ublk_param_integrity to struct
ublk_params to specify the integrity params of a ublk device.
UBLK_PARAM_TYPE_INTEGRITY requires UBLK_F_INTEGRITY and a nonzero
metadata_size. The LBMD_PI_CAP_* and LBMD_PI_CSUM_* values from the
linux/fs.h UAPI header are used for the flags and csum_type fields.
If the UBLK_PARAM_TYPE_INTEGRITY flag is set, validate the integrity
parameters and apply them to the blk_integrity limits.
The struct ublk_param_integrity validations are based on the checks in
blk_validate_integrity_limits(). Any invalid parameters should be
rejected before being applied to struct blk_integrity.
[csander: drop redundant pi_tuple_size field, use block metadata UAPI
constants, add param validation]
Signed-off-by: Stanley Zhang <stazhang@purestorage.com>
Signed-off-by: Caleb Sander Mateos <csander@purestorage.com>
Reviewed-by: Ming Lei <ming.lei@redhat.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
ublk_dev_support_user_copy() will be used in ublk_validate_params().
Move these functions next to ublk_{dev,queue}_is_zoned() to avoid
needing to forward-declare them.
Signed-off-by: Caleb Sander Mateos <csander@purestorage.com>
Reviewed-by: Ming Lei <ming.lei@redhat.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
Merge in fixes that went to 6.19 after for-7.0/block was branched.
Pending ublk changes depend on particularly the async scan work.
* block-6.19:
block: zero non-PI portion of auto integrity buffer
ublk: fix use-after-free in ublk_partition_scan_work
blk-mq: avoid stall during boot due to synchronize_rcu_expedited
loop: add missing bd_abort_claiming in loop_set_status
block: don't merge bios with different app_tags
blk-rq-qos: Remove unlikely() hints from QoS checks
loop: don't change loop device under exclusive opener in loop_set_status
block, bfq: update outdated comment
blk-mq: skip CPU offline notify on unmapped hctx
selftests/ublk: fix Makefile to rebuild on header changes
selftests/ublk: add test for async partition scan
ublk: scan partition in async way
block,bfq: fix aux stat accumulation destination
md: Fix forward incompatibility from configurable logical block size
md: Fix logical_block_size configuration being overwritten
md: suspend array while updating raid_disks via sysfs
md/raid5: fix possible null-pointer dereferences in raid5_store_group_thread_cnt()
md: Fix static checker warning in analyze_sbs
-----BEGIN PGP SIGNATURE-----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=DaMl
-----END PGP SIGNATURE-----
Merge tag 'block-6.19-20260109' of git://git.kernel.org/pub/scm/linux/kernel/git/axboe/linux
Pull block fixes from Jens Axboe:
- Kill unlikely checks for blk-rq-qos. These checks are really
all-or-nothing, either the branch is taken all the time, or it's not.
Depending on the configuration, either one of those cases may be
true. Just remove the annotation
- Fix for merging bios with different app tags set
- Fix for a recently introduced slowdown due to RCU synchronization
- Fix for a status change on loop while it's in use, and then a later
fix for that fix
- Fix for the async partition scanning in ublk
* tag 'block-6.19-20260109' of git://git.kernel.org/pub/scm/linux/kernel/git/axboe/linux:
ublk: fix use-after-free in ublk_partition_scan_work
blk-mq: avoid stall during boot due to synchronize_rcu_expedited
loop: add missing bd_abort_claiming in loop_set_status
block: don't merge bios with different app_tags
blk-rq-qos: Remove unlikely() hints from QoS checks
loop: don't change loop device under exclusive opener in loop_set_status
A race condition exists between the async partition scan work and device
teardown that can lead to a use-after-free of ub->ub_disk:
1. ublk_ctrl_start_dev() schedules partition_scan_work after add_disk()
2. ublk_stop_dev() calls ublk_stop_dev_unlocked() which does:
- del_gendisk(ub->ub_disk)
- ublk_detach_disk() sets ub->ub_disk = NULL
- put_disk() which may free the disk
3. The worker ublk_partition_scan_work() then dereferences ub->ub_disk
leading to UAF
Fix this by using ublk_get_disk()/ublk_put_disk() in the worker to hold
a reference to the disk during the partition scan. The spinlock in
ublk_get_disk() synchronizes with ublk_detach_disk() ensuring the worker
either gets a valid reference or sees NULL and exits early.
Also change flush_work() to cancel_work_sync() to avoid running the
partition scan work unnecessarily when the disk is already detached.
Fixes: 7fc4da6a30 ("ublk: scan partition in async way")
Reported-by: Ruikai Peng <ruikai@pwno.io>
Signed-off-by: Ming Lei <ming.lei@redhat.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
loop_set_status() is allowed to change the loop device while there
are other openers of the device, even exclusive ones.
In this case, it causes a KASAN: slab-out-of-bounds Read in
ext4_search_dir(), since when looking for an entry in an inlined
directory, e_value_offs is changed underneath the filesystem by
loop_set_status().
Fix the problem by forbidding loop_set_status() from modifying the loop
device while there are exclusive openers of the device. This is similar
to the fix in loop_configure() by commit 33ec3e53e7 ("loop: Don't
change loop device under exclusive opener") alongside commit ecbe6bc000
("block: use bd_prepare_to_claim directly in the loop driver").
Reported-by: syzbot+3ee481e21fd75e14c397@syzkaller.appspotmail.com
Closes: https://syzkaller.appspot.com/bug?extid=3ee481e21fd75e14c397
Tested-by: syzbot+3ee481e21fd75e14c397@syzkaller.appspotmail.com
Tested-by: Yongpeng Yang <yangyongpeng@xiaomi.com>
Signed-off-by: Raphael Pinsonneault-Thibeault <rpthibeault@gmail.com>
Reviewed-by: Jan Kara <jack@suse.cz>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
Before using the data buffer to send back the response message, zero it
completely. This prevents any stray bytes to be picked up by the client
side when there the message is exchanged between different protocol
versions.
Signed-off-by: Md Haris Iqbal <haris.iqbal@ionos.com>
Signed-off-by: Jack Wang <jinpu.wang@ionos.com>
Signed-off-by: Grzegorz Prajsner <grzegorz.prajsner@ionos.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
On rnbd-srv, the bi_size of the bio is set during the bio_add_page
function, to which datalen is passed. But for special IOs like DISCARD
and WRITE_ZEROES, datalen is 0, since there is no data to write. For
these special IOs, use the bi_size of the rnbd_msg_io.
Fixes: f6f84be089 ("block/rnbd-srv: Add sanity check and remove redundant assignment")
Signed-off-by: Florian-Ewald Mueller <florian-ewald.mueller@ionos.com>
Signed-off-by: Md Haris Iqbal <haris.iqbal@ionos.com>
Signed-off-by: Grzegorz Prajsner <grzegorz.prajsner@ionos.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
The __print_flags helper meant for bitmask, while the rnbd_rw_flags is
mixed with bitmask and enum, to avoid confusion, just print the data
as it is.
Signed-off-by: Jack Wang <jinpu.wang@ionos.com>
Reviewed-by: Md Haris Iqbal <haris.iqbal@ionos.com>
Signed-off-by: Grzegorz Prajsner <grzegorz.prajsner@ionos.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
The NOUNMAP flag is in combination with WRITE_ZEROES flag to indicate
that the upper layers wants the sectors zeroed, but does not want it to
get freed. This instruction is especially important for storage stacks
which involves a layer capable of thin provisioning.
This commit makes RNBD block device transfer and retain this NOUNMAP flag
for requests, so it can be passed onto the backend device on the server
side.
Since it is a change in the wire protocol, bump the minor version of
protocol.
Signed-off-by: Md Haris Iqbal <haris.iqbal@ionos.com>
Signed-off-by: Jack Wang <jinpu.wang@ionos.com>
Signed-off-by: Grzegorz Prajsner <grzegorz.prajsner@ionos.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
Every ktype must provides a .release function that will be called after
the last kobject_put.
Signed-off-by: Zhu Yanjun <yanjun.zhu@linux.dev>
Reviewed-by: Md Haris Iqbal <haris.iqbal@ionos.com>
Signed-off-by: Grzegorz Prajsner <grzegorz.prajsner@ionos.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
In RNBD client, for a WRITE request of size 0, with only the REQ_PREFLUSH
bit set, while converting from bio_opf to rnbd_opf, we do REQ_OP_WRITE to
RNBD_OP_WRITE, and then check if the rq is flush through function
op_is_flush. That function checks both REQ_PREFLUSH and REQ_FUA flag, and
if any of them is set, the RNBD_F_FUA is set.
On the RNBD server side, while converting the RNBD flags to req flags, if
the RNBD_F_FUA flag is set, we just set the REQ_FUA flag. This means we
have lost the PREFLUSH flag, and added the REQ_FUA flag in its place.
This commits adds a new RNBD_F_PREFLUSH flag, and also adds separate
handling for REQ_PREFLUSH flag. On the server side, if the RNBD_F_PREFLUSH
is present, the REQ_PREFLUSH is added to the bio.
Since it is a change in the wire protocol, bump the minor version of
protocol.
The change is backwards compatible, and does not change the functionality
if either the client or the server is running older/newer versions.
If the client side is running the older version, both REQ_PREFLUSH and
REQ_FUA is converted to RNBD_F_FUA. The server running newer one would
still add only the REQ_FUA flag which is what happens when both client and
server is running the older version.
If the client side is running the newer version, just like before a
RNBD_F_FUA is added, but now a RNBD_F_PREFLUSH is also added to the
rnbd_opf. In case the server is running the older version the
RNBD_F_PREFLUSH is ignored, and only the RNBD_F_FUA is processed.
Signed-off-by: Md Haris Iqbal <haris.iqbal@ionos.com>
Reviewed-by: Jack Wang <jinpu.wang@ionos.com>
Reviewed-by: Florian-Ewald Mueller <florian-ewald.mueller@ionos.com>
Signed-off-by: Grzegorz Prajsner <grzegorz.prajsner@ionos.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
-----BEGIN PGP SIGNATURE-----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=4NB3
-----END PGP SIGNATURE-----
Merge tag 'block-6.19-20260102' of git://git.kernel.org/pub/scm/linux/kernel/git/axboe/linux
Pull block fixes from Jens Axboe:
- Scan partition tables asynchronously for ublk, similarly to how nvme
does it. This avoids potential deadlocks, which is why nvme does it
that way too. Includes a set of selftests as well.
- MD pull request via Yu:
- Fix null-pointer dereference in raid5 sysfs group_thread_cnt
store (Tuo Li)
- Fix possible mempool corruption during raid1 raid_disks update
via sysfs (FengWei Shih)
- Fix logical_block_size configuration being overwritten during
super_1_validate() (Li Nan)
- Fix forward incompatibility with configurable logical block size:
arrays assembled on new kernels could not be assembled on older
kernels (v6.18 and before) due to non-zero reserved pad rejection
(Li Nan)
- Fix static checker warning about iterator not incremented (Li Nan)
- Skip CPU offlining notifications on unmapped hardware queues
- bfq-iosched block stats fix
- Fix outdated comment in bfq-iosched
* tag 'block-6.19-20260102' of git://git.kernel.org/pub/scm/linux/kernel/git/axboe/linux:
block, bfq: update outdated comment
blk-mq: skip CPU offline notify on unmapped hctx
selftests/ublk: fix Makefile to rebuild on header changes
selftests/ublk: add test for async partition scan
ublk: scan partition in async way
block,bfq: fix aux stat accumulation destination
md: Fix forward incompatibility from configurable logical block size
md: Fix logical_block_size configuration being overwritten
md: suspend array while updating raid_disks via sysfs
md/raid5: fix possible null-pointer dereferences in raid5_store_group_thread_cnt()
md: Fix static checker warning in analyze_sbs
'struct configfs_item_operations' and 'configfs_group_operations' are not
modified in this driver.
Constifying these structures moves some data to a read-only section, so
increases overall security, especially when the structure holds some
function pointers.
On a x86_64, with allmodconfig:
Before:
======
text data bss dec hex filename
100263 37808 2752 140823 22617 drivers/block/null_blk/main.o
After:
=====
text data bss dec hex filename
100423 37648 2752 140823 22617 drivers/block/null_blk/main.o
Signed-off-by: Christophe JAILLET <christophe.jaillet@wanadoo.fr>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
Replace simple_strtol() with the recommended kstrtoul() for parsing the
'ramdisk_size=' boot parameter. Unlike simple_strtol(), which returns a
long, kstrtoul() converts the string directly to an unsigned long and
avoids implicit casting.
Check the return value of kstrtoul() and reject invalid values. This
adds error handling while preserving behavior for existing values, and
removes use of the deprecated simple_strtol() helper. The current code
silently sets 'rd_size = 0' if parsing fails, instead of leaving the
default value (CONFIG_BLK_DEV_RAM_SIZE) unchanged.
Signed-off-by: Thorsten Blum <thorsten.blum@linux.dev>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
C-String literals were added in Rust 1.77. Replace instances of
`kernel::c_str!` with C-String literals where possible.
Signed-off-by: Tamir Duberstein <tamird@gmail.com>
Reviewed-by: Daniel Almeida <daniel.almeida@collabora.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
Implement async partition scan to avoid IO hang when reading partition
tables. Similar to nvme_partition_scan_work(), partition scanning is
deferred to a work queue to prevent deadlocks.
When partition scan happens synchronously during add_disk(), IO errors
can cause the partition scan to wait while holding ub->mutex, which
can deadlock with other operations that need the mutex.
Changes:
- Add partition_scan_work to ublk_device structure
- Implement ublk_partition_scan_work() to perform async scan
- Always suppress sync partition scan during add_disk()
- Schedule async work after add_disk() for trusted daemons
- Add flush_work() in ublk_stop_dev() before grabbing ub->mutex
Reviewed-by: Caleb Sander Mateos <csander@purestorage.com>
Reported-by: Yoav Cohen <yoav@nvidia.com>
Closes: https://lore.kernel.org/linux-block/DM4PR12MB63280C5637917C071C2F0D65A9A8A@DM4PR12MB6328.namprd12.prod.outlook.com/
Fixes: 71f28f3136 ("ublk_drv: add io_uring based userspace block driver")
Signed-off-by: Ming Lei <ming.lei@redhat.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
-----BEGIN PGP SIGNATURE-----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=DwyX
-----END PGP SIGNATURE-----
Merge tag 'block-6.19-20251226' of git://git.kernel.org/pub/scm/linux/kernel/git/axboe/linux
Pull block fixes from Jens Axboe:
- Fix for a signedness issue introduced in this kernel release for rnbd
- Fix up user copy references for ublk when the server exits
* tag 'block-6.19-20251226' of git://git.kernel.org/pub/scm/linux/kernel/git/axboe/linux:
block: rnbd-clt: Fix signedness bug in init_dev()
ublk: clean up user copy references on ublk server exit
The "dev->clt_device_id" variable is set using ida_alloc_max() which
returns an int and in particular it returns negative error codes.
Change the type from u32 to int to fix the error checking.
Fixes: c9b5645fd8 ("block: rnbd-clt: Fix leaked ID in init_dev()")
Signed-off-by: Dan Carpenter <dan.carpenter@linaro.org>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
If a ublk server process releases a ublk char device file, any requests
dispatched to the ublk server but not yet completed will retain a ref
value of UBLK_REFCOUNT_INIT. Before commit e63d2228ef ("ublk: simplify
aborting ublk request"), __ublk_fail_req() would decrement the reference
count before completing the failed request. However, that commit
optimized __ublk_fail_req() to call __ublk_complete_rq() directly
without decrementing the request reference count.
The leaked reference count incorrectly allows user copy and zero copy
operations on the completed ublk request. It also triggers the
WARN_ON_ONCE(refcount_read(&io->ref)) warnings in ublk_queue_reinit()
and ublk_deinit_queue().
Commit c5c5eb24ed ("ublk: avoid ublk_io_release() called after ublk
char dev is closed") already fixed the issue for ublk devices using
UBLK_F_SUPPORT_ZERO_COPY or UBLK_F_AUTO_BUF_REG. However, the reference
count leak also affects UBLK_F_USER_COPY, the other reference-counted
data copy mode. Fix the condition in ublk_check_and_reset_active_ref()
to include all reference-counted data copy modes. This ensures that any
ublk requests still owned by the ublk server when it exits have their
reference counts reset to 0.
Signed-off-by: Caleb Sander Mateos <csander@purestorage.com>
Fixes: e63d2228ef ("ublk: simplify aborting ublk request")
Reviewed-by: Ming Lei <ming.lei@redhat.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
-----BEGIN PGP SIGNATURE-----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=lk7H
-----END PGP SIGNATURE-----
Merge tag 'block-6.19-20251218' of git://git.kernel.org/pub/scm/linux/kernel/git/axboe/linux
Pull block fixes from Jens Axboe:
- ublk selftests for missing coverage
- two fixes for the block integrity code
- fix for the newly added newly added PR read keys ioctl, limiting the
memory that can be allocated
- work around for a deadlock that can occur with ublk, where partition
scanning ends up recursing back into file closure, which needs the
same mutex grabbed. Not the prettiest thing in the world, but an
acceptable work-around until we can eliminate the reliance on
disk->open_mutex for this
- fix for a race between enabling writeback throttling and new IO
submissions
- move a bit of bio flag handling code. No changes, but needed for a
patchset for a future kernel
- fix for an init time id leak failure in rnbd
- loop/zloop state check fix
* tag 'block-6.19-20251218' of git://git.kernel.org/pub/scm/linux/kernel/git/axboe/linux:
block: validate interval_exp integrity limit
block: validate pi_offset integrity limit
block: rnbd-clt: Fix leaked ID in init_dev()
ublk: fix deadlock when reading partition table
block: add allocation size check in blkdev_pr_read_keys()
Documentation: admin-guide: blockdev: replace zone_capacity with zone_capacity_mb when creating devices
zloop: use READ_ONCE() to read lo->lo_state in queue_rq path
loop: use READ_ONCE() to read lo->lo_state without locking
block: fix race between wbt_enable_default and IO submission
selftests: ublk: add user copy test cases
selftests: ublk: add support for user copy to kublk
selftests: ublk: forbid multiple data copy modes
selftests: ublk: don't share backing files between ublk servers
selftests: ublk: use auto_zc for PER_IO_DAEMON tests in stress_04
selftests: ublk: fix fio arguments in run_io_and_recover()
selftests: ublk: remove unused ios map in seq_io.bt
selftests: ublk: correct last_rw map type in seq_io.bt
selftests: ublk: fix overflow in ublk_queue_auto_zc_fallback()
block: move around bio flagging helpers
If kstrdup() fails in init_dev(), then the newly allocated ID is lost.
Fixes: 64e8a6ece1 ("block/rnbd-clt: Dynamically alloc buffer for pathname & blk_symlink_name")
Signed-off-by: Thomas Fourier <fourier.thomas@gmail.com>
Acked-by: Jack Wang <jinpu.wang@ionos.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
When one process(such as udev) opens ublk block device (e.g., to read
the partition table via bdev_open()), a deadlock[1] can occur:
1. bdev_open() grabs disk->open_mutex
2. The process issues read I/O to ublk backend to read partition table
3. In __ublk_complete_rq(), blk_update_request() or blk_mq_end_request()
runs bio->bi_end_io() callbacks
4. If this triggers fput() on file descriptor of ublk block device, the
work may be deferred to current task's task work (see fput() implementation)
5. This eventually calls blkdev_release() from the same context
6. blkdev_release() tries to grab disk->open_mutex again
7. Deadlock: same task waiting for a mutex it already holds
The fix is to run blk_update_request() and blk_mq_end_request() with bottom
halves disabled. This forces blkdev_release() to run in kernel work-queue
context instead of current task work context, and allows ublk server to make
forward progress, and avoids the deadlock.
Fixes: 71f28f3136 ("ublk_drv: add io_uring based userspace block driver")
Link: https://github.com/ublk-org/ublksrv/issues/170 [1]
Signed-off-by: Ming Lei <ming.lei@redhat.com>
Reviewed-by: Caleb Sander Mateos <csander@purestorage.com>
[axboe: rewrite comment in ublk]
Signed-off-by: Jens Axboe <axboe@kernel.dk>
In the queue_rq path, zlo->state is accessed without locking, and direct
access may read stale data. This patch uses READ_ONCE() to read
zlo->state and data_race() to silence code checkers, and changes all
assignments to use WRITE_ONCE().
Reviewed-by: Damien Le Moal <dlemoal@kernel.org>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Yongpeng Yang <yangyongpeng@xiaomi.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
When lo->lo_mutex is not held, direct access may read stale data. This
patch uses READ_ONCE() to read lo->lo_state and data_race() to silence
code checkers, and changes all assignments to use WRITE_ONCE().
Reviewed-by: Damien Le Moal <dlemoal@kernel.org>
Signed-off-by: Yongpeng Yang <yangyongpeng@xiaomi.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
client from Max, a fix that hardens osdmap parsing code from myself
(marked for stable) and a few assorted fixups.
-----BEGIN PGP SIGNATURE-----
iQFHBAABCAAxFiEEydHwtzie9C7TfviiSn/eOAIR84sFAmk8YxITHGlkcnlvbW92
QGdtYWlsLmNvbQAKCRBKf944AhHzi702B/9Mfj0HQSAaWCyMz6GJAv8+1ijVTSbG
nTFeMmipYZhPn188OvWqHsf1cw9rWY0fzenIEW05Tk3YmMvYdeRmCcOkZdeG06xw
um8XxX4L8315E0b98CCpQpVa02ux7XoNtBPjeHccl8PEErJQgQJrQ3Cc/C8kk5U5
a0KlfeVRXYWkOPJva3+wosOu0t9QgJ9ABt5stqcvYDfdkKfvatQMBN3N1nNRKkFH
yhNPv+nRtypSk8jiHhKeeCVmosC0L7MnKuO593vDr761cY5mKrgKFqc2LLlPF6r0
/p13s5SG6X38RUegWCjcK4XRJAzVcR/tyod8LkVVp8d5DC/ptcyy8H+I
=h1gC
-----END PGP SIGNATURE-----
Merge tag 'ceph-for-6.19-rc1' of https://github.com/ceph/ceph-client
Pull ceph updates from Ilya Dryomov:
"We have a patch that adds an initial set of tracepoints to the MDS
client from Max, a fix that hardens osdmap parsing code from myself
(marked for stable) and a few assorted fixups"
* tag 'ceph-for-6.19-rc1' of https://github.com/ceph/ceph-client:
rbd: stop selecting CRC32, CRYPTO, and CRYPTO_AES
ceph: stop selecting CRC32, CRYPTO, and CRYPTO_AES
libceph: make decode_pool() more resilient against corrupted osdmaps
libceph: Amend checking to fix `make W=1` build breakage
ceph: Amend checking to fix `make W=1` build breakage
ceph: add trace points to the MDS client
libceph: fix log output race condition in OSD client
-----BEGIN PGP SIGNATURE-----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=h5ad
-----END PGP SIGNATURE-----
Merge tag 'block-6.19-20251211' of git://git.kernel.org/pub/scm/linux/kernel/git/axboe/linux
Pull block fixes from Jens Axboe:
- Always initialize DMA state, fixing a potentially nasty issue on the
block side
- btrfs zoned write fix with cached zone reports
- Fix corruption issues in bcache with chained bio's, and further make
it clear that the chained IO handler is simply a marker, it's not
code meant to be executed
- Kill old code dealing with synchronous IO polling in the block layer,
that has been dead for a long time. Only async polling is supported
these days
- Fix a lockdep issue in tag_set management, moving it to RCU
- Fix an issue with ublks bio_vec iteration
- Don't unconditionally enforce blocking issue of ublk control
commands, allow some of them with non-blocking issue as they
do not block
* tag 'block-6.19-20251211' of git://git.kernel.org/pub/scm/linux/kernel/git/axboe/linux:
blk-mq-dma: always initialize dma state
blk-mq: delete task running check in blk_hctx_poll()
block: fix cached zone reports on devices with native zone append
block: Use RCU in blk_mq_[un]quiesce_tagset() instead of set->tag_list_lock
ublk: don't mutate struct bio_vec in iteration
block: prohibit calls to bio_chain_endio
bcache: fix improper use of bi_end_io
ublk: allow non-blocking ctrl cmds in IO_URING_F_NONBLOCK issue
None of the RBD code directly requires CRC32, CRYPTO, or CRYPTO_AES.
These options are needed by CEPH_LIB code and they are selected there
directly.
Signed-off-by: Ilya Dryomov <idryomov@gmail.com>
Reviewed-by: Dongsheng Yang <dongsheng.yang@linux.dev>
__bio_for_each_segment() uses the returned struct bio_vec's bv_len field
to advance the struct bvec_iter at the end of each loop iteration. So
it's incorrect to modify it during the loop. Don't assign to bv_len (or
bv_offset, for that matter) in ublk_copy_user_pages().
Signed-off-by: Caleb Sander Mateos <csander@purestorage.com>
Fixes: e87d66ab27 ("ublk: use rq_for_each_segment() for user copy")
Reviewed-by: Ming Lei <ming.lei@redhat.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
-----BEGIN PGP SIGNATURE-----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=r1xa
-----END PGP SIGNATURE-----
Merge tag 'block-6.19-20251208' of git://git.kernel.org/pub/scm/linux/kernel/git/axboe/linux
Pull block updates from Jens Axboe:
"Followup set of fixes and updates for block for the 6.19 merge window.
NVMe had some late minute debates which lead to dropping some patches
from that tree, which is why the initial PR didn't have NVMe included.
It's here now. This pull request contains:
- NVMe pull request via Keith:
- Subsystem usage cleanups (Max)
- Endpoint device fixes (Shin'ichiro)
- Debug statements (Gerd)
- FC fabrics cleanups and fixes (Daniel)
- Consistent alloc API usages (Israel)
- Code comment updates (Chu)
- Authentication retry fix (Justin)
- Fix a memory leak in the discard ioctl code, if the task is being
interrupted by a signal at just the wrong time
- Zoned write plugging fixes
- Add ioctls for for persistent reservations
- Enable per-cpu bio caching by default
- Various little fixes and tweaks"
* tag 'block-6.19-20251208' of git://git.kernel.org/pub/scm/linux/kernel/git/axboe/linux: (27 commits)
nvme-fabrics: add ENOKEY to no retry criteria for authentication failures
nvme-auth: use kvfree() for memory allocated with kvcalloc()
nvmet-tcp: use kvcalloc for commands array
nvmet-rdma: use kvcalloc for commands and responses arrays
nvme: fix typo error in nvme target
nvmet-fc: use pr_* print macros instead of dev_*
nvmet-fcloop: remove unused lsdir member.
nvmet-fcloop: check all request and response have been processed
nvme-fc: check all request and response have been processed
block: fix memory leak in __blkdev_issue_zero_pages
block: fix comment for op_is_zone_mgmt() to include RESET_ALL
block: Clear BLK_ZONE_WPLUG_PLUGGED when aborting plugged BIOs
blk-mq: Abort suspend when wakeup events are pending
blk-mq: add blk_rq_nr_bvec() helper
block: add IOC_PR_READ_RESERVATION ioctl
block: add IOC_PR_READ_KEYS ioctl
nvme: reject invalid pr_read_keys() num_keys values
scsi: sd: reject invalid pr_read_keys() num_keys values
block: enable per-cpu bio cache by default
block: use bio_alloc_bioset for passthru IO by default
...
Handling most of the ublksrv_ctrl_cmd opcodes require locking a mutex,
so ublk_ctrl_uring_cmd() bails out with EAGAIN when called with the
IO_URING_F_NONBLOCK issue flag. However, several opcodes can be handled
without blocking:
- UBLK_CMD_GET_QUEUE_AFFINITY
- UBLK_CMD_GET_DEV_INFO
- UBLK_CMD_GET_DEV_INFO2
- UBLK_U_CMD_GET_FEATURES
Handle these opcodes synchronously instead of returning EAGAIN so
io_uring doesn't need to issue the command via the worker thread pool.
Signed-off-by: Caleb Sander Mateos <csander@purestorage.com>
Reviewed-by: Ming Lei <ming.lei@redhat.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
- The 10 patch series "__vmalloc()/kvmalloc() and no-block support" from
Uladzislau Rezki reworks the vmalloc() code to support non-blocking
allocations (GFP_ATOIC, GFP_NOWAIT).
- The 2 patch series "ksm: fix exec/fork inheritance" from xu xin fixes
a rare case where the KSM MMF_VM_MERGE_ANY prctl state is not inherited
across fork/exec.
- The 4 patch series "mm/zswap: misc cleanup of code and documentations"
from SeongJae Park does some light maintenance work on the zswap code.
- The 5 patch series "mm/page_owner: add debugfs files 'show_handles'
and 'show_stacks_handles'" from Mauricio Faria de Oliveira enhances the
/sys/kernel/debug/page_owner debug feature. It adds unique identifiers
to differentiate the various stack traces so that userspace monitoring
tools can better match stack traces over time.
- The 2 patch series "mm/page_alloc: pcp->batch cleanups" from Joshua
Hahn makes some minor alterations to the page allocator's per-cpu-pages
feature.
- The 2 patch series "Improve UFFDIO_MOVE scalability by removing
anon_vma lock" from Lokesh Gidra addresses a scalability issue in
userfaultfd's UFFDIO_MOVE operation.
- The 2 patch series "kasan: cleanups for kasan_enabled() checks" from
Sabyrzhan Tasbolatov performs some cleanup in the KASAN code.
- The 2 patch series "drivers/base/node: fold node register and
unregister functions" from Donet Tom cleans up the NUMA node handling
code a little.
- The 4 patch series "mm: some optimizations for prot numa" from Kefeng
Wang provides some cleanups and small optimizations to the NUMA
allocation hinting code.
- The 5 patch series "mm/page_alloc: Batch callers of
free_pcppages_bulk" from Joshua Hahn addresses long lock hold times at
boot on large machines. These were causing (harmless) softlockup
warnings.
- The 2 patch series "optimize the logic for handling dirty file folios
during reclaim" from Baolin Wang removes some now-unnecessary work from
page reclaim.
- The 10 patch series "mm/damon: allow DAMOS auto-tuned for per-memcg
per-node memory usage" from SeongJae Park enhances the DAMOS auto-tuning
feature.
- The 2 patch series "mm/damon: fixes for address alignment issues in
DAMON_LRU_SORT and DAMON_RECLAIM" from Quanmin Yan fixes DAMON_LRU_SORT
and DAMON_RECLAIM with certain userspace configuration.
- The 15 patch series "expand mmap_prepare functionality, port more
users" from Lorenzo Stoakes enhances the new(ish)
file_operations.mmap_prepare() method and ports additional callsites
from the old ->mmap() over to ->mmap_prepare().
- The 8 patch series "Fix stale IOTLB entries for kernel address space"
from Lu Baolu fixes a bug (and possible security issue on non-x86) in
the IOMMU code. In some situations the IOMMU could be left hanging onto
a stale kernel pagetable entry.
- The 4 patch series "mm/huge_memory: cleanup __split_unmapped_folio()"
from Wei Yang cleans up and optimizes the folio splitting code.
- The 5 patch series "mm, swap: misc cleanup and bugfix" from Kairui
Song implements some cleanups and a minor fix in the swap discard code.
- The 8 patch series "mm/damon: misc documentation fixups" from SeongJae
Park does as advertised.
- The 9 patch series "mm/damon: support pin-point targets removal" from
SeongJae Park permits userspace to remove a specific monitoring target
in the middle of the current targets list.
- The 2 patch series "mm: MISC follow-up patches for linux/pgalloc.h"
from Harry Yoo implements a couple of cleanups related to mm header file
inclusion.
- The 2 patch series "mm/swapfile.c: select swap devices of default
priority round robin" from Baoquan He improves the selection of swap
devices for NUMA machines.
- The 3 patch series "mm: Convert memory block states (MEM_*) macros to
enums" from Israel Batista changes the memory block labels from macros
to enums so they will appear in kernel debug info.
- The 3 patch series "ksm: perform a range-walk to jump over holes in
break_ksm" from Pedro Demarchi Gomes addresses an inefficiency when KSM
unmerges an address range.
- The 22 patch series "mm/damon/tests: fix memory bugs in kunit tests"
from SeongJae Park fixes leaks and unhandled malloc() failures in DAMON
userspace unit tests.
- The 2 patch series "some cleanups for pageout()" from Baolin Wang
cleans up a couple of minor things in the page scanner's
writeback-for-eviction code.
- The 2 patch series "mm/hugetlb: refactor sysfs/sysctl interfaces" from
Hui Zhu moves hugetlb's sysfs/sysctl handling code into a new file.
- The 9 patch series "introduce VM_MAYBE_GUARD and make it sticky" from
Lorenzo Stoakes makes the VMA guard regions available in /proc/pid/smaps
and improves the mergeability of guarded VMAs.
- The 2 patch series "mm: perform guard region install/remove under VMA
lock" from Lorenzo Stoakes reduces mmap lock contention for callers
performing VMA guard region operations.
- The 2 patch series "vma_start_write_killable" from Matthew Wilcox
starts work in permitting applications to be killed when they are
waiting on a read_lock on the VMA lock.
- The 11 patch series "mm/damon/tests: add more tests for online
parameters commit" from SeongJae Park adds additional userspace testing
of DAMON's "commit" feature.
- The 9 patch series "mm/damon: misc cleanups" from SeongJae Park does
that.
- The 2 patch series "make VM_SOFTDIRTY a sticky VMA flag" from Lorenzo
Stoakes addresses the possible loss of a VMA's VM_SOFTDIRTY flag when
that VMA is merged with another.
- The 16 patch series "mm: support device-private THP" from Balbir Singh
introduces support for Transparent Huge Page (THP) migration in zone
device-private memory.
- The 3 patch series "Optimize folio split in memory failure" from Zi
Yan optimizes folio split operations in the memory failure code.
- The 2 patch series "mm/huge_memory: Define split_type and consolidate
split support checks" from Wei Yang provides some more cleanups in the
folio splitting code.
- The 16 patch series "mm: remove is_swap_[pte, pmd]() + non-swap
entries, introduce leaf entries" from Lorenzo Stoakes cleans up our
handling of pagetable leaf entries by introducing the concept of
'software leaf entries', of type softleaf_t.
- The 4 patch series "reparent the THP split queue" from Muchun Song
reparents the THP split queue to its parent memcg. This is in
preparation for addressing the long-standing "dying memcg" problem,
wherein dead memcg's linger for too long, consuming memory resources.
- The 3 patch series "unify PMD scan results and remove redundant
cleanup" from Wei Yang does a little cleanup in the hugepage collapse
code.
- The 6 patch series "zram: introduce writeback bio batching" from
Sergey Senozhatsky improves zram writeback efficiency by introducing
batched bio writeback support.
- The 4 patch series "memcg: cleanup the memcg stats interfaces" from
Shakeel Butt cleans up our handling of the interrupt safety of some
memcg stats.
- The 4 patch series "make vmalloc gfp flags usage more apparent" from
Vishal Moola cleans up vmalloc's handling of incoming GFP flags.
- The 6 patch series "mm: Add soft-dirty and uffd-wp support for RISC-V"
from Chunyan Zhang teches soft dirty and userfaultfd write protect
tracking to use RISC-V's Svrsw60t59b extension.
- The 5 patch series "mm: swap: small fixes and comment cleanups" from
Youngjun Park fixes a small bug and cleans up some of the swap code.
- The 4 patch series "initial work on making VMA flags a bitmap" from
Lorenzo Stoakes starts work on converting the vma struct's flags to a
bitmap, so we stop running out of them, especially on 32-bit.
- The 2 patch series "mm/swapfile: fix and cleanup swap list iterations"
from Youngjun Park addresses a possible bug in the swap discard code and
cleans things up a little.
-----BEGIN PGP SIGNATURE-----
iHUEABYKAB0WIQTTMBEPP41GrTpTJgfdBJ7gKXxAjgUCaTEb0wAKCRDdBJ7gKXxA
jjfIAP94W4EkCCwNOupnChoG+YWw/JW21anXt5NN+i5svn1yugEAwzvv6A+cAFng
o+ug/fyrfPZG7PLp2R8WFyGIP0YoBA4=
=IUzS
-----END PGP SIGNATURE-----
Merge tag 'mm-stable-2025-12-03-21-26' of git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm
Pull MM updates from Andrew Morton:
"__vmalloc()/kvmalloc() and no-block support" (Uladzislau Rezki)
Rework the vmalloc() code to support non-blocking allocations
(GFP_ATOIC, GFP_NOWAIT)
"ksm: fix exec/fork inheritance" (xu xin)
Fix a rare case where the KSM MMF_VM_MERGE_ANY prctl state is not
inherited across fork/exec
"mm/zswap: misc cleanup of code and documentations" (SeongJae Park)
Some light maintenance work on the zswap code
"mm/page_owner: add debugfs files 'show_handles' and 'show_stacks_handles'" (Mauricio Faria de Oliveira)
Enhance the /sys/kernel/debug/page_owner debug feature by adding
unique identifiers to differentiate the various stack traces so
that userspace monitoring tools can better match stack traces over
time
"mm/page_alloc: pcp->batch cleanups" (Joshua Hahn)
Minor alterations to the page allocator's per-cpu-pages feature
"Improve UFFDIO_MOVE scalability by removing anon_vma lock" (Lokesh Gidra)
Address a scalability issue in userfaultfd's UFFDIO_MOVE operation
"kasan: cleanups for kasan_enabled() checks" (Sabyrzhan Tasbolatov)
"drivers/base/node: fold node register and unregister functions" (Donet Tom)
Clean up the NUMA node handling code a little
"mm: some optimizations for prot numa" (Kefeng Wang)
Cleanups and small optimizations to the NUMA allocation hinting
code
"mm/page_alloc: Batch callers of free_pcppages_bulk" (Joshua Hahn)
Address long lock hold times at boot on large machines. These were
causing (harmless) softlockup warnings
"optimize the logic for handling dirty file folios during reclaim" (Baolin Wang)
Remove some now-unnecessary work from page reclaim
"mm/damon: allow DAMOS auto-tuned for per-memcg per-node memory usage" (SeongJae Park)
Enhance the DAMOS auto-tuning feature
"mm/damon: fixes for address alignment issues in DAMON_LRU_SORT and DAMON_RECLAIM" (Quanmin Yan)
Fix DAMON_LRU_SORT and DAMON_RECLAIM with certain userspace
configuration
"expand mmap_prepare functionality, port more users" (Lorenzo Stoakes)
Enhance the new(ish) file_operations.mmap_prepare() method and port
additional callsites from the old ->mmap() over to ->mmap_prepare()
"Fix stale IOTLB entries for kernel address space" (Lu Baolu)
Fix a bug (and possible security issue on non-x86) in the IOMMU
code. In some situations the IOMMU could be left hanging onto a
stale kernel pagetable entry
"mm/huge_memory: cleanup __split_unmapped_folio()" (Wei Yang)
Clean up and optimize the folio splitting code
"mm, swap: misc cleanup and bugfix" (Kairui Song)
Some cleanups and a minor fix in the swap discard code
"mm/damon: misc documentation fixups" (SeongJae Park)
"mm/damon: support pin-point targets removal" (SeongJae Park)
Permit userspace to remove a specific monitoring target in the
middle of the current targets list
"mm: MISC follow-up patches for linux/pgalloc.h" (Harry Yoo)
A couple of cleanups related to mm header file inclusion
"mm/swapfile.c: select swap devices of default priority round robin" (Baoquan He)
improve the selection of swap devices for NUMA machines
"mm: Convert memory block states (MEM_*) macros to enums" (Israel Batista)
Change the memory block labels from macros to enums so they will
appear in kernel debug info
"ksm: perform a range-walk to jump over holes in break_ksm" (Pedro Demarchi Gomes)
Address an inefficiency when KSM unmerges an address range
"mm/damon/tests: fix memory bugs in kunit tests" (SeongJae Park)
Fix leaks and unhandled malloc() failures in DAMON userspace unit
tests
"some cleanups for pageout()" (Baolin Wang)
Clean up a couple of minor things in the page scanner's
writeback-for-eviction code
"mm/hugetlb: refactor sysfs/sysctl interfaces" (Hui Zhu)
Move hugetlb's sysfs/sysctl handling code into a new file
"introduce VM_MAYBE_GUARD and make it sticky" (Lorenzo Stoakes)
Make the VMA guard regions available in /proc/pid/smaps and
improves the mergeability of guarded VMAs
"mm: perform guard region install/remove under VMA lock" (Lorenzo Stoakes)
Reduce mmap lock contention for callers performing VMA guard region
operations
"vma_start_write_killable" (Matthew Wilcox)
Start work on permitting applications to be killed when they are
waiting on a read_lock on the VMA lock
"mm/damon/tests: add more tests for online parameters commit" (SeongJae Park)
Add additional userspace testing of DAMON's "commit" feature
"mm/damon: misc cleanups" (SeongJae Park)
"make VM_SOFTDIRTY a sticky VMA flag" (Lorenzo Stoakes)
Address the possible loss of a VMA's VM_SOFTDIRTY flag when that
VMA is merged with another
"mm: support device-private THP" (Balbir Singh)
Introduce support for Transparent Huge Page (THP) migration in zone
device-private memory
"Optimize folio split in memory failure" (Zi Yan)
"mm/huge_memory: Define split_type and consolidate split support checks" (Wei Yang)
Some more cleanups in the folio splitting code
"mm: remove is_swap_[pte, pmd]() + non-swap entries, introduce leaf entries" (Lorenzo Stoakes)
Clean up our handling of pagetable leaf entries by introducing the
concept of 'software leaf entries', of type softleaf_t
"reparent the THP split queue" (Muchun Song)
Reparent the THP split queue to its parent memcg. This is in
preparation for addressing the long-standing "dying memcg" problem,
wherein dead memcg's linger for too long, consuming memory
resources
"unify PMD scan results and remove redundant cleanup" (Wei Yang)
A little cleanup in the hugepage collapse code
"zram: introduce writeback bio batching" (Sergey Senozhatsky)
Improve zram writeback efficiency by introducing batched bio
writeback support
"memcg: cleanup the memcg stats interfaces" (Shakeel Butt)
Clean up our handling of the interrupt safety of some memcg stats
"make vmalloc gfp flags usage more apparent" (Vishal Moola)
Clean up vmalloc's handling of incoming GFP flags
"mm: Add soft-dirty and uffd-wp support for RISC-V" (Chunyan Zhang)
Teach soft dirty and userfaultfd write protect tracking to use
RISC-V's Svrsw60t59b extension
"mm: swap: small fixes and comment cleanups" (Youngjun Park)
Fix a small bug and clean up some of the swap code
"initial work on making VMA flags a bitmap" (Lorenzo Stoakes)
Start work on converting the vma struct's flags to a bitmap, so we
stop running out of them, especially on 32-bit
"mm/swapfile: fix and cleanup swap list iterations" (Youngjun Park)
Address a possible bug in the swap discard code and clean things
up a little
[ This merge also reverts commit ebb9aeb980 ("vfio/nvgrace-gpu:
register device memory for poison handling") because it looks
broken to me, I've asked for clarification - Linus ]
* tag 'mm-stable-2025-12-03-21-26' of git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm: (321 commits)
mm: fix vma_start_write_killable() signal handling
mm/swapfile: use plist_for_each_entry in __folio_throttle_swaprate
mm/swapfile: fix list iteration when next node is removed during discard
fs/proc/task_mmu.c: fix make_uffd_wp_huge_pte() huge pte handling
mm/kfence: add reboot notifier to disable KFENCE on shutdown
memcg: remove inc/dec_lruvec_kmem_state helpers
selftests/mm/uffd: initialize char variable to Null
mm: fix DEBUG_RODATA_TEST indentation in Kconfig
mm: introduce VMA flags bitmap type
tools/testing/vma: eliminate dependency on vma->__vm_flags
mm: simplify and rename mm flags function for clarity
mm: declare VMA flags by bit
zram: fix a spelling mistake
mm/page_alloc: optimize lowmem_reserve max lookup using its semantic monotonicity
mm/vmscan: skip increasing kswapd_failures when reclaim was boosted
pagemap: update BUDDY flag documentation
mm: swap: remove scan_swap_map_slots() references from comments
mm: swap: change swap_alloc_slow() to void
mm, swap: remove redundant comment for read_swap_cache_async
mm, swap: use SWP_SOLIDSTATE to determine if swap is rotational
...
Add a new helper function blk_rq_nr_bvec() that returns the number of
bvecs in a request. This count represents the number of iterations
rq_for_each_bvec() would perform on a request.
Drivers need to pre-allocate bvec arrays before iterating through
a request's bvecs. Currently, they manually count bvecs using
rq_for_each_bvec() in a loop, which is repetitive. The new helper
centralizes this logic.
This pattern exists in loop and zloop drivers, where multi-bio requests
require copying bvecs into a contiguous array before creating
an iov_iter for file operations.
Update loop and zloop drivers to use the new helper, eliminating
duplicate code.
This patch also provides a clear API to avoid any potential misuse of
blk_nr_phys_segments() for calculating the bvecs since, one bvec can
have more than one segments and use of blk_nr_phys_segments() can
lead to extra memory allocation :-
[ 6155.673749] nullb_bio: 128K bio as ONE bvec: sector=0, size=131072
[ 6155.673846] null_blk: #### null_handle_data_transfer:1375
[ 6155.673850] null_blk: nr_bvec=1 blk_rq_nr_phys_segments=2
[ 6155.674263] null_blk: #### null_handle_data_transfer:1375
[ 6155.674267] null_blk: nr_bvec=1 blk_rq_nr_phys_segments=1
Reviewed-by: Niklas Cassel <cassel@kernel.org>
Signed-off-by: Chaitanya Kulkarni <ckulkarnilinux@gmail.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
-----BEGIN PGP SIGNATURE-----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=m22w
-----END PGP SIGNATURE-----
Merge tag 'for-6.19/block-20251201' of git://git.kernel.org/pub/scm/linux/kernel/git/axboe/linux
Pull block updates from Jens Axboe:
- Fix head insertion for mq-deadline, a regression from when priority
support was added
- Series simplifying and improving the ublk user copy code
- Various ublk related cleanups
- Fixup REQ_NOWAIT handling in loop/zloop, clearing NOWAIT when the
request is punted to a thread for handling
- Merge and then later revert loop dio nowait support, as it ended up
causing excessive stack usage for when the inline issue code needs to
dip back into the full file system code
- Improve auto integrity code, making it less deadlock prone
- Speedup polled IO handling, but manually managing the hctx lookups
- Fixes for blk-throttle for SSD devices
- Small series with fixes for the S390 dasd driver
- Add support for caching zones, avoiding unnecessary report zone
queries
- MD pull requests via Yu:
- fix null-ptr-dereference regression for dm-raid0
- fix IO hang for raid5 when array is broken with IO inflight
- remove legacy 1s delay to speed up system shutdown
- change maintainer's email address
- data can be lost if array is created with different lbs devices,
fix this problem and record lbs of the array in metadata
- fix rcu protection for md_thread
- fix mddev kobject lifetime regression
- enable atomic writes for md-linear
- some cleanups
- bcache updates via Coly
- remove useless discard and cache device code
- improve usage of per-cpu workqueues
- Reorganize the IO scheduler switching code, fixing some lockdep
reports as well
- Improve the block layer P2P DMA support
- Add support to the block tracing code for zoned devices
- Segment calculation improves, and memory alignment flexibility
improvements
- Set of prep and cleanups patches for ublk batching support. The
actual batching hasn't been added yet, but helps shrink down the
workload of getting that patchset ready for 6.20
- Fix for how the ps3 block driver handles segments offsets
- Improve how block plugging handles batch tag allocations
- nbd fixes for use-after-free of the configuration on device clear/put
- Set of improvements and fixes for zloop
- Add Damien as maintainer of the block zoned device code handling
- Various other fixes and cleanups
* tag 'for-6.19/block-20251201' of git://git.kernel.org/pub/scm/linux/kernel/git/axboe/linux: (162 commits)
block/rnbd: correct all kernel-doc complaints
blk-mq: use queue_hctx in blk_mq_map_queue_type
md: remove legacy 1s delay in md_notify_reboot
md/raid5: fix IO hang when array is broken with IO inflight
md: warn about updating super block failure
md/raid0: fix NULL pointer dereference in create_strip_zones() for dm-raid
sbitmap: fix all kernel-doc warnings
ublk: add helper of __ublk_fetch()
ublk: pass const pointer to ublk_queue_is_zoned()
ublk: refactor auto buffer register in ublk_dispatch_req()
ublk: add `union ublk_io_buf` with improved naming
ublk: add parameter `struct io_uring_cmd *` to ublk_prep_auto_buf_reg()
kfifo: add kfifo_alloc_node() helper for NUMA awareness
blk-mq: fix potential uaf for 'queue_hw_ctx'
blk-mq: use array manage hctx map instead of xarray
ublk: prevent invalid access with DEBUG
s390/dasd: Use scnprintf() instead of sprintf()
s390/dasd: Move device name formatting into separate function
s390/dasd: Remove unnecessary debugfs_create() return checks
s390/dasd: Fix gendisk parent after copy pair swap
...
-----BEGIN PGP SIGNATURE-----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=4g/f
-----END PGP SIGNATURE-----
Merge tag 'for-6.19/io_uring-20251201' of git://git.kernel.org/pub/scm/linux/kernel/git/axboe/linux
Pull io_uring updates from Jens Axboe:
- Unify how task_work cancelations are detected, placing it in the
task_work running state rather than needing to check the task state
- Series cleaning up and moving the cancelation code to where it
belongs, in cancel.c
- Cleanup of waitid and futex argument handling
- Add support for mixed sized SQEs. 6.18 added support for mixed sized
CQEs, improving flexibility and efficiency of workloads that need big
CQEs. This adds similar support for SQEs, where the occasional need
for a 128b SQE doesn't necessitate having all SQEs be 128b in size
- Introduce zcrx and SQ/CQ layout queries. The former returns what zcrx
features are available. And both return the ring size information to
help with allocation size calculation for user provided rings like
IORING_SETUP_NO_MMAP and IORING_MEM_REGION_TYPE_USER
- Zcrx updates for 6.19. It includes a bunch of small patches,
IORING_REGISTER_ZCRX_CTRL and RQ flushing and David's work on sharing
zcrx b/w multiple io_uring instances
- Series cleaning up ring initializations, notable deduplicating ring
size and offset calculations. It also moves most of the checking
before doing any allocations, making the code simpler
- Add support for getsockname and getpeername, which is mostly a
trivial hookup after a bit of refactoring on the networking side
- Various fixes and cleanups
* tag 'for-6.19/io_uring-20251201' of git://git.kernel.org/pub/scm/linux/kernel/git/axboe/linux: (68 commits)
io_uring: Introduce getsockname io_uring cmd
socket: Split out a getsockname helper for io_uring
socket: Unify getsockname and getpeername implementation
io_uring/query: drop unused io_handle_query_entry() ctx arg
io_uring/kbuf: remove obsolete buf_nr_pages and update comments
io_uring/register: use correct location for io_rings_layout
io_uring/zcrx: share an ifq between rings
io_uring/zcrx: add io_fill_zcrx_offsets()
io_uring/zcrx: export zcrx via a file
io_uring/zcrx: move io_zcrx_scrub() and dependencies up
io_uring/zcrx: count zcrx users
io_uring/zcrx: add sync refill queue flushing
io_uring/zcrx: introduce IORING_REGISTER_ZCRX_CTRL
io_uring/zcrx: elide passing msg flags
io_uring/zcrx: use folio_nr_pages() instead of shift operation
io_uring/zcrx: convert to use netmem_desc
io_uring/query: introduce rings info query
io_uring/query: introduce zcrx query
io_uring: move cq/sq user offset init around
io_uring: pre-calculate scq layout
...
Core & protocols
----------------
- Replace busylock at the Tx queuing layer with a lockless list. Resulting
in a 300% (4x) improvement on heavy TX workloads, sending twice the
number of packets per second, for half the cpu cycles.
- Allow constantly busy flows to migrate to a more suitable CPU/NIC
queue. Normally we perform queue re-selection when flow comes out
of idle, but under extreme circumstances the flows may be constantly
busy. Add sysctl to allow periodic rehashing even if it'd risk packet
reordering.
- Optimize the NAPI skb cache, make it larger, use it in more paths.
- Attempt returning Tx skbs to the originating CPU (like we already did
for Rx skbs).
- Various data structure layout and prefetch optimizations from Eric.
- Remove ktime_get() from the recvmsg() fast path, ktime_get() is sadly
quite expensive on recent AMD machines.
- Extend threaded NAPI polling to allow the kthread busy poll for packets.
- Make MPTCP use Rx backlog processing. This lowers the lock pressure,
improving the Rx performance.
- Support memcg accounting of MPTCP socket memory.
- Allow admin to opt sockets out of global protocol memory accounting
(using a sysctl or BPF-based policy). The global limits are a poor fit
for modern container workloads, where limits are imposed using cgroups.
- Improve heuristics for when to kick off AF_UNIX garbage collection.
- Allow users to control TCP SACK compression, and default to 33% of RTT.
- Add tcp_rcvbuf_low_rtt sysctl to let datacenter users avoid unnecessarily
aggressive rcvbuf growth and overshot when the connection RTT is low.
- Preserve skb metadata space across skb_push / skb_pull operations.
- Support for IPIP encapsulation in the nftables flowtable offload.
- Support appending IP interface information to ICMP messages (RFC 5837).
- Support setting max record size in TLS (RFC 8449).
- Remove taking rtnl_lock from RTM_GETNEIGHTBL and RTM_SETNEIGHTBL.
- Use a dedicated lock (and RCU) in MPLS, instead of rtnl_lock.
- Let users configure the number of write buffers in SMC.
- Add new struct sockaddr_unsized for sockaddr of unknown length,
from Kees.
- Some conversions away from the crypto_ahash API, from Eric Biggers.
- Some preparations for slimming down struct page.
- YAML Netlink protocol spec for WireGuard.
- Add a tool on top of YAML Netlink specs/lib for reporting commonly
computed derived statistics and summarized system state.
Driver API
----------
- Add CAN XL support to the CAN Netlink interface.
- Add uAPI for reporting PHY Mean Square Error (MSE) diagnostics,
as defined by the OPEN Alliance's "Advanced diagnostic features
for 100BASE-T1 automotive Ethernet PHYs" specification.
- Add DPLL phase-adjust-gran pin attribute (and implement it in zl3073x).
- Refactor xfrm_input lock to reduce contention when NIC offloads IPsec
and performs RSS.
- Add info to devlink params whether the current setting is the default
or a user override. Allow resetting back to default.
- Add standard device stats for PSP crypto offload.
- Leverage DSA frame broadcast to implement simple HSR frame duplication
for a lot of switches without dedicated HSR offload.
- Add uAPI defines for 1.6Tbps link modes.
Device drivers
--------------
- Add Motorcomm YT921x gigabit Ethernet switch support.
- Add MUCSE driver for N500/N210 1GbE NIC series.
- Convert drivers to support dedicated ops for timestamping control,
and away from the direct IOCTL handling. While at it support GET
operations for PHY timestamping.
- Add (and convert most drivers to) a dedicated ethtool callback
for reading the Rx ring count.
- Significant refactoring efforts in the STMMAC driver, which supports
Synopsys turn-key MAC IP integrated into a ton of SoCs.
- Ethernet high-speed NICs:
- Broadcom (bnxt):
- support PPS in/out on all pins
- Intel (100G, ice, idpf):
- ice: implement standard ethtool and timestamping stats
- i40e: support setting the max number of MAC addresses per VF
- iavf: support RSS of GTP tunnels for 5G and LTE deployments
- nVidia/Mellanox (mlx5):
- reduce downtime on interface reconfiguration
- disable being an XDP redirect target by default (same as other
drivers) to avoid wasting resources if feature is unused
- Meta (fbnic):
- add support for Linux-managed PCS on 25G, 50G, and 100G links
- Wangxun:
- support Rx descriptor merge, and Tx head writeback
- support Rx coalescing offload
- support 25G SPF and 40G QSFP modules
- Ethernet virtual:
- Google (gve):
- allow ethtool to configure rx_buf_len
- implement XDP HW RX Timestamping support for DQ descriptor format
- Microsoft vNIC (mana):
- support HW link state events
- handle hardware recovery events when probing the device
- Ethernet NICs consumer, and embedded:
- usbnet: add support for Byte Queue Limits (BQL)
- AMD (amd-xgbe):
- add device selftests
- NXP (enetc):
- add i.MX94 support
- Broadcom integrated MACs (bcmgenet, bcmasp):
- bcmasp: add support for PHY-based Wake-on-LAN
- Broadcom switches (b53):
- support port isolation
- support BCM5389/97/98 and BCM63XX ARL formats
- Lantiq/MaxLinear switches:
- support bridge FDB entries on the CPU port
- use regmap for register access
- allow user to enable/disable learning
- support Energy Efficient Ethernet
- support configuring RMII clock delays
- add tagging driver for MaxLinear GSW1xx switches
- Synopsys (stmmac):
- support using the HW clock in free running mode
- add Eswin EIC7700 support
- add Rockchip RK3506 support
- add Altera Agilex5 support
- Cadence (macb):
- cleanup and consolidate descriptor and DMA address handling
- add EyeQ5 support
- TI:
- icssg-prueth: support AF_XDP
- Airoha access points:
- add missing Ethernet stats and link state callback
- add AN7583 support
- support out-of-order Tx completion processing
- Power over Ethernet:
- pd692x0: preserve PSE configuration across reboots
- add support for TPS23881B devices
- Ethernet PHYs:
- Open Alliance OATC14 10BASE-T1S PHY cable diagnostic support
- Support 50G SerDes and 100G interfaces in Linux-managed PHYs
- micrel:
- support for non PTP SKUs of lan8814
- enable in-band auto-negotiation on lan8814
- realtek:
- cable testing support on RTL8224
- interrupt support on RTL8221B
- motorcomm: support for PHY LEDs on YT853
- microchip: support for LAN867X Rev.D0 PHYs w/ SQI and cable diag
- mscc: support for PHY LED control
- CAN drivers:
- m_can: add support for optional reset and system wake up
- remove can_change_mtu() obsoleted by core handling
- mcp251xfd: support GPIO controller functionality
- Bluetooth:
- add initial support for PASTa
- WiFi:
- split ieee80211.h file, it's way too big
- improvements in VHT radiotap reporting, S1G, Channel Switch
Announcement handling, rate tracking in mesh networks
- improve multi-radio monitor mode support, and add a cfg80211 debugfs
interface for it
- HT action frame handling on 6 GHz
- initial chanctx work towards NAN
- MU-MIMO sniffer improvements
- WiFi drivers:
- RealTek (rtw89):
- support USB devices RTL8852AU and RTL8852CU
- initial work for RTL8922DE
- improved injection support
- Intel:
- iwlwifi: new sniffer API support
- MediaTek (mt76):
- WED support for >32-bit DMA
- airoha NPU support
- regdomain improvements
- continued WiFi7/MLO work
- Qualcomm/Atheros:
- ath10k: factory test support
- ath11k: TX power insertion support
- ath12k: BSS color change support
- ath12k: statistics improvements
- brcmfmac: Acer A1 840 tablet quirk
- rtl8xxxu: 40 MHz connection fixes/support
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
-----BEGIN PGP SIGNATURE-----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=UoDR
-----END PGP SIGNATURE-----
Merge tag 'net-next-6.19' of git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net-next
Pull networking updates from Jakub Kicinski:
"Core & protocols:
- Replace busylock at the Tx queuing layer with a lockless list.
Resulting in a 300% (4x) improvement on heavy TX workloads, sending
twice the number of packets per second, for half the cpu cycles.
- Allow constantly busy flows to migrate to a more suitable CPU/NIC
queue.
Normally we perform queue re-selection when flow comes out of idle,
but under extreme circumstances the flows may be constantly busy.
Add sysctl to allow periodic rehashing even if it'd risk packet
reordering.
- Optimize the NAPI skb cache, make it larger, use it in more paths.
- Attempt returning Tx skbs to the originating CPU (like we already
did for Rx skbs).
- Various data structure layout and prefetch optimizations from Eric.
- Remove ktime_get() from the recvmsg() fast path, ktime_get() is
sadly quite expensive on recent AMD machines.
- Extend threaded NAPI polling to allow the kthread busy poll for
packets.
- Make MPTCP use Rx backlog processing. This lowers the lock
pressure, improving the Rx performance.
- Support memcg accounting of MPTCP socket memory.
- Allow admin to opt sockets out of global protocol memory accounting
(using a sysctl or BPF-based policy). The global limits are a poor
fit for modern container workloads, where limits are imposed using
cgroups.
- Improve heuristics for when to kick off AF_UNIX garbage collection.
- Allow users to control TCP SACK compression, and default to 33% of
RTT.
- Add tcp_rcvbuf_low_rtt sysctl to let datacenter users avoid
unnecessarily aggressive rcvbuf growth and overshot when the
connection RTT is low.
- Preserve skb metadata space across skb_push / skb_pull operations.
- Support for IPIP encapsulation in the nftables flowtable offload.
- Support appending IP interface information to ICMP messages (RFC
5837).
- Support setting max record size in TLS (RFC 8449).
- Remove taking rtnl_lock from RTM_GETNEIGHTBL and RTM_SETNEIGHTBL.
- Use a dedicated lock (and RCU) in MPLS, instead of rtnl_lock.
- Let users configure the number of write buffers in SMC.
- Add new struct sockaddr_unsized for sockaddr of unknown length,
from Kees.
- Some conversions away from the crypto_ahash API, from Eric Biggers.
- Some preparations for slimming down struct page.
- YAML Netlink protocol spec for WireGuard.
- Add a tool on top of YAML Netlink specs/lib for reporting commonly
computed derived statistics and summarized system state.
Driver API:
- Add CAN XL support to the CAN Netlink interface.
- Add uAPI for reporting PHY Mean Square Error (MSE) diagnostics, as
defined by the OPEN Alliance's "Advanced diagnostic features for
100BASE-T1 automotive Ethernet PHYs" specification.
- Add DPLL phase-adjust-gran pin attribute (and implement it in
zl3073x).
- Refactor xfrm_input lock to reduce contention when NIC offloads
IPsec and performs RSS.
- Add info to devlink params whether the current setting is the
default or a user override. Allow resetting back to default.
- Add standard device stats for PSP crypto offload.
- Leverage DSA frame broadcast to implement simple HSR frame
duplication for a lot of switches without dedicated HSR offload.
- Add uAPI defines for 1.6Tbps link modes.
Device drivers:
- Add Motorcomm YT921x gigabit Ethernet switch support.
- Add MUCSE driver for N500/N210 1GbE NIC series.
- Convert drivers to support dedicated ops for timestamping control,
and away from the direct IOCTL handling. While at it support GET
operations for PHY timestamping.
- Add (and convert most drivers to) a dedicated ethtool callback for
reading the Rx ring count.
- Significant refactoring efforts in the STMMAC driver, which
supports Synopsys turn-key MAC IP integrated into a ton of SoCs.
- Ethernet high-speed NICs:
- Broadcom (bnxt):
- support PPS in/out on all pins
- Intel (100G, ice, idpf):
- ice: implement standard ethtool and timestamping stats
- i40e: support setting the max number of MAC addresses per VF
- iavf: support RSS of GTP tunnels for 5G and LTE deployments
- nVidia/Mellanox (mlx5):
- reduce downtime on interface reconfiguration
- disable being an XDP redirect target by default (same as
other drivers) to avoid wasting resources if feature is
unused
- Meta (fbnic):
- add support for Linux-managed PCS on 25G, 50G, and 100G links
- Wangxun:
- support Rx descriptor merge, and Tx head writeback
- support Rx coalescing offload
- support 25G SPF and 40G QSFP modules
- Ethernet virtual:
- Google (gve):
- allow ethtool to configure rx_buf_len
- implement XDP HW RX Timestamping support for DQ descriptor
format
- Microsoft vNIC (mana):
- support HW link state events
- handle hardware recovery events when probing the device
- Ethernet NICs consumer, and embedded:
- usbnet: add support for Byte Queue Limits (BQL)
- AMD (amd-xgbe):
- add device selftests
- NXP (enetc):
- add i.MX94 support
- Broadcom integrated MACs (bcmgenet, bcmasp):
- bcmasp: add support for PHY-based Wake-on-LAN
- Broadcom switches (b53):
- support port isolation
- support BCM5389/97/98 and BCM63XX ARL formats
- Lantiq/MaxLinear switches:
- support bridge FDB entries on the CPU port
- use regmap for register access
- allow user to enable/disable learning
- support Energy Efficient Ethernet
- support configuring RMII clock delays
- add tagging driver for MaxLinear GSW1xx switches
- Synopsys (stmmac):
- support using the HW clock in free running mode
- add Eswin EIC7700 support
- add Rockchip RK3506 support
- add Altera Agilex5 support
- Cadence (macb):
- cleanup and consolidate descriptor and DMA address handling
- add EyeQ5 support
- TI:
- icssg-prueth: support AF_XDP
- Airoha access points:
- add missing Ethernet stats and link state callback
- add AN7583 support
- support out-of-order Tx completion processing
- Power over Ethernet:
- pd692x0: preserve PSE configuration across reboots
- add support for TPS23881B devices
- Ethernet PHYs:
- Open Alliance OATC14 10BASE-T1S PHY cable diagnostic support
- Support 50G SerDes and 100G interfaces in Linux-managed PHYs
- micrel:
- support for non PTP SKUs of lan8814
- enable in-band auto-negotiation on lan8814
- realtek:
- cable testing support on RTL8224
- interrupt support on RTL8221B
- motorcomm: support for PHY LEDs on YT853
- microchip: support for LAN867X Rev.D0 PHYs w/ SQI and cable diag
- mscc: support for PHY LED control
- CAN drivers:
- m_can: add support for optional reset and system wake up
- remove can_change_mtu() obsoleted by core handling
- mcp251xfd: support GPIO controller functionality
- Bluetooth:
- add initial support for PASTa
- WiFi:
- split ieee80211.h file, it's way too big
- improvements in VHT radiotap reporting, S1G, Channel Switch
Announcement handling, rate tracking in mesh networks
- improve multi-radio monitor mode support, and add a cfg80211
debugfs interface for it
- HT action frame handling on 6 GHz
- initial chanctx work towards NAN
- MU-MIMO sniffer improvements
- WiFi drivers:
- RealTek (rtw89):
- support USB devices RTL8852AU and RTL8852CU
- initial work for RTL8922DE
- improved injection support
- Intel:
- iwlwifi: new sniffer API support
- MediaTek (mt76):
- WED support for >32-bit DMA
- airoha NPU support
- regdomain improvements
- continued WiFi7/MLO work
- Qualcomm/Atheros:
- ath10k: factory test support
- ath11k: TX power insertion support
- ath12k: BSS color change support
- ath12k: statistics improvements
- brcmfmac: Acer A1 840 tablet quirk
- rtl8xxxu: 40 MHz connection fixes/support"
* tag 'net-next-6.19' of git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net-next: (1381 commits)
net: page_pool: sanitise allocation order
net: page pool: xa init with destroy on pp init
net/mlx5e: Support XDP target xmit with dummy program
net/mlx5e: Update XDP features in switch channels
selftests/tc-testing: Test CAKE scheduler when enqueue drops packets
net/sched: sch_cake: Fix incorrect qlen reduction in cake_drop
wireguard: netlink: generate netlink code
wireguard: uapi: generate header with ynl-gen
wireguard: uapi: move flag enums
wireguard: uapi: move enum wg_cmd
wireguard: netlink: add YNL specification
selftests: drv-net: Fix tolerance calculation in devlink_rate_tc_bw.py
selftests: drv-net: Fix and clarify TC bandwidth split in devlink_rate_tc_bw.py
selftests: drv-net: Set shell=True for sysfs writes in devlink_rate_tc_bw.py
selftests: drv-net: Use Iperf3Runner in devlink_rate_tc_bw.py
selftests: drv-net: introduce Iperf3Runner for measurement use cases
selftests: drv-net: Add devlink_rate_tc_bw.py to TEST_PROGS
net: ps3_gelic_net: Use napi_alloc_skb() and napi_gro_receive()
Documentation: net: dsa: mention simple HSR offload helpers
Documentation: net: dsa: mention availability of RedBox
...
Toolchain and infrastructure:
- Add support for 'syn'.
Syn is a parsing library for parsing a stream of Rust tokens into a
syntax tree of Rust source code.
Currently this library is geared toward use in Rust procedural
macros, but contains some APIs that may be useful more generally.
'syn' allows us to greatly simplify writing complex macros such as
'pin-init' (Benno has already prepared the 'syn'-based version). We
will use it in the 'macros' crate too.
'syn' is the most downloaded Rust crate (according to crates.io), and
it is also used by the Rust compiler itself. While the amount of code
is substantial, there should not be many updates needed for these
crates, and even if there are, they should not be too big, e.g. +7k
-3k lines across the 3 crates in the last year.
'syn' requires two smaller dependencies: 'quote' and 'proc-macro2'.
I only modified their code to remove a third dependency
('unicode-ident') and to add the SPDX identifiers. The code can be
easily verified to exactly match upstream with the provided scripts.
They are all licensed under "Apache-2.0 OR MIT", like the other
vendored 'alloc' crate we had for a while.
Please see the merge commit with the cover letter for more context.
- Allow 'unreachable_pub' and 'clippy::disallowed_names' for doctests.
Examples (i.e. doctests) may want to do things like show public items
and use names such as 'foo'.
Nevertheless, we still try to keep examples as close to real code as
possible (this is part of why running Clippy on doctests is important
for us, e.g. for safety comments, which userspace Rust does not
support yet but we are stricter).
'kernel' crate:
- Replace our custom 'CStr' type with 'core::ffi::CStr'.
Using the standard library type reduces our custom code footprint,
and we retain needed custom functionality through an extension trait
and a new 'fmt!' macro which replaces the previous 'core' import.
This started in 6.17 and continued in 6.18, and we finally land the
replacement now. This required quite some stamina from Tamir, who
split the changes in steps to prepare for the flag day change here.
- Replace 'kernel::c_str!' with C string literals.
C string literals were added in Rust 1.77, which produce '&CStr's
(the 'core' one), so now we can write:
c"hi"
instead of:
c_str!("hi")
- Add 'num' module for numerical features.
It includes the 'Integer' trait, implemented for all primitive
integer types.
It also includes the 'Bounded' integer wrapping type: an integer
value that requires only the 'N' less significant bits of the wrapped
type to be encoded:
// An unsigned 8-bit integer, of which only the 4 LSBs are used.
let v = Bounded::<u8, 4>:🆕:<15>();
assert_eq!(v.get(), 15);
'Bounded' is useful to e.g. enforce guarantees when working with
bitfields that have an arbitrary number of bits.
Values can be constructed from simple non-constant expressions or,
for more complex ones, validated at runtime.
'Bounded' also comes with comparison and arithmetic operations (with
both their backing type and other 'Bounded's with a compatible
backing type), casts to change the backing type, extending/shrinking
and infallible/fallible conversions from/to primitives as applicable.
- 'rbtree' module: add immutable cursor ('Cursor').
It enables to use just an immutable tree reference where appropriate.
The existing fully-featured mutable cursor is renamed to 'CursorMut'.
kallsyms:
- Fix wrong "big" kernel symbol type read from procfs.
'pin-init' crate:
- A couple minor fixes (Benno asked me to pick these patches up for
him this cycle).
Documentation:
- Quick Start guide: add Debian 13 (Trixie).
Debian Stable is now able to build Linux, since Debian 13 (released
2025-08-09) packages Rust 1.85.0, which is recent enough.
We are planning to propose that the minimum supported Rust version in
Linux follows Debian Stable releases, with Debian 13 being the first
one we upgrade to, i.e. Rust 1.85.
MAINTAINERS:
- Add entry for the new 'num' module.
- Remove Alex as Rust maintainer: he hasn't had the time to contribute
for a few years now, so it is a no-op change in practice.
And a few other cleanups and improvements.
-----BEGIN PGP SIGNATURE-----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=9nM+
-----END PGP SIGNATURE-----
Merge tag 'rust-6.19' of git://git.kernel.org/pub/scm/linux/kernel/git/ojeda/linux
Pull Rust updates from Miguel Ojeda:
"Toolchain and infrastructure:
- Add support for 'syn'.
Syn is a parsing library for parsing a stream of Rust tokens into a
syntax tree of Rust source code.
Currently this library is geared toward use in Rust procedural
macros, but contains some APIs that may be useful more generally.
'syn' allows us to greatly simplify writing complex macros such as
'pin-init' (Benno has already prepared the 'syn'-based version). We
will use it in the 'macros' crate too.
'syn' is the most downloaded Rust crate (according to crates.io),
and it is also used by the Rust compiler itself. While the amount
of code is substantial, there should not be many updates needed for
these crates, and even if there are, they should not be too big,
e.g. +7k -3k lines across the 3 crates in the last year.
'syn' requires two smaller dependencies: 'quote' and 'proc-macro2'.
I only modified their code to remove a third dependency
('unicode-ident') and to add the SPDX identifiers. The code can be
easily verified to exactly match upstream with the provided
scripts.
They are all licensed under "Apache-2.0 OR MIT", like the other
vendored 'alloc' crate we had for a while.
Please see the merge commit with the cover letter for more context.
- Allow 'unreachable_pub' and 'clippy::disallowed_names' for
doctests.
Examples (i.e. doctests) may want to do things like show public
items and use names such as 'foo'.
Nevertheless, we still try to keep examples as close to real code
as possible (this is part of why running Clippy on doctests is
important for us, e.g. for safety comments, which userspace Rust
does not support yet but we are stricter).
'kernel' crate:
- Replace our custom 'CStr' type with 'core::ffi::CStr'.
Using the standard library type reduces our custom code footprint,
and we retain needed custom functionality through an extension
trait and a new 'fmt!' macro which replaces the previous 'core'
import.
This started in 6.17 and continued in 6.18, and we finally land the
replacement now. This required quite some stamina from Tamir, who
split the changes in steps to prepare for the flag day change here.
- Replace 'kernel::c_str!' with C string literals.
C string literals were added in Rust 1.77, which produce '&CStr's
(the 'core' one), so now we can write:
c"hi"
instead of:
c_str!("hi")
- Add 'num' module for numerical features.
It includes the 'Integer' trait, implemented for all primitive
integer types.
It also includes the 'Bounded' integer wrapping type: an integer
value that requires only the 'N' least significant bits of the
wrapped type to be encoded:
// An unsigned 8-bit integer, of which only the 4 LSBs are used.
let v = Bounded::<u8, 4>:🆕:<15>();
assert_eq!(v.get(), 15);
'Bounded' is useful to e.g. enforce guarantees when working with
bitfields that have an arbitrary number of bits.
Values can also be constructed from simple non-constant expressions
or, for more complex ones, validated at runtime.
'Bounded' also comes with comparison and arithmetic operations
(with both their backing type and other 'Bounded's with a
compatible backing type), casts to change the backing type,
extending/shrinking and infallible/fallible conversions from/to
primitives as applicable.
- 'rbtree' module: add immutable cursor ('Cursor').
It enables to use just an immutable tree reference where
appropriate. The existing fully-featured mutable cursor is renamed
to 'CursorMut'.
kallsyms:
- Fix wrong "big" kernel symbol type read from procfs.
'pin-init' crate:
- A couple minor fixes (Benno asked me to pick these patches up for
him this cycle).
Documentation:
- Quick Start guide: add Debian 13 (Trixie).
Debian Stable is now able to build Linux, since Debian 13 (released
2025-08-09) packages Rust 1.85.0, which is recent enough.
We are planning to propose that the minimum supported Rust version
in Linux follows Debian Stable releases, with Debian 13 being the
first one we upgrade to, i.e. Rust 1.85.
MAINTAINERS:
- Add entry for the new 'num' module.
- Remove Alex as Rust maintainer: he hasn't had the time to
contribute for a few years now, so it is a no-op change in
practice.
And a few other cleanups and improvements"
* tag 'rust-6.19' of git://git.kernel.org/pub/scm/linux/kernel/git/ojeda/linux: (53 commits)
rust: macros: support `proc-macro2`, `quote` and `syn`
rust: syn: enable support in kbuild
rust: syn: add `README.md`
rust: syn: remove `unicode-ident` dependency
rust: syn: add SPDX License Identifiers
rust: syn: import crate
rust: quote: enable support in kbuild
rust: quote: add `README.md`
rust: quote: add SPDX License Identifiers
rust: quote: import crate
rust: proc-macro2: enable support in kbuild
rust: proc-macro2: add `README.md`
rust: proc-macro2: remove `unicode_ident` dependency
rust: proc-macro2: add SPDX License Identifiers
rust: proc-macro2: import crate
rust: kbuild: support using libraries in `rustc_procmacro`
rust: kbuild: support skipping flags in `rustc_test_library`
rust: kbuild: add proc macro library support
rust: kbuild: simplify `--cfg` handling
rust: kbuild: introduce `core-flags` and `core-skip_flags`
...
-----BEGIN PGP SIGNATURE-----
iHUEABYKAB0WIQRAhzRXHqcMeLMyaSiRxhvAZXjcogUCaSmOZQAKCRCRxhvAZXjc
orJLAP9UD+dX6cicJDkzFZowDakmoIQkR5ZSDwChSlmvLcmquwEAlSq4svVd9Bdl
7kOFUk71DqhVHrPAwO7ap0BxehokEAA=
=Cli6
-----END PGP SIGNATURE-----
Merge tag 'kernel-6.19-rc1.cred' of git://git.kernel.org/pub/scm/linux/kernel/git/vfs/vfs
Pull cred guard updates from Christian Brauner:
"This contains substantial credential infrastructure improvements
adding guard-based credential management that simplifies code and
eliminates manual reference counting in many subsystems.
Features:
- Kernel Credential Guards
Add with_kernel_creds() and scoped_with_kernel_creds() guards that
allow using the kernel credentials without allocating and copying
them. This was requested by Linus after seeing repeated
prepare_kernel_creds() calls that duplicate the kernel credentials
only to drop them again later.
The new guards completely avoid the allocation and never expose the
temporary variable to hold the kernel credentials anywhere in
callers.
- Generic Credential Guards
Add scoped_with_creds() guards for the common override_creds() and
revert_creds() pattern. This builds on earlier work that made
override_creds()/revert_creds() completely reference count free.
- Prepare Credential Guards
Add prepare credential guards for the more complex pattern of
preparing a new set of credentials and overriding the current
credentials with them:
- prepare_creds()
- modify new creds
- override_creds()
- revert_creds()
- put_cred()
Cleanups:
- Make init_cred static since it should not be directly accessed
- Add kernel_cred() helper to properly access the kernel credentials
- Fix scoped_class() macro that was introduced two cycles ago
- coredump: split out do_coredump() from vfs_coredump() for cleaner
credential handling
- coredump: move revert_cred() before coredump_cleanup()
- coredump: mark struct mm_struct as const
- coredump: pass struct linux_binfmt as const
- sev-dev: use guard for path"
* tag 'kernel-6.19-rc1.cred' of git://git.kernel.org/pub/scm/linux/kernel/git/vfs/vfs: (36 commits)
trace: use override credential guard
trace: use prepare credential guard
coredump: use override credential guard
coredump: use prepare credential guard
coredump: split out do_coredump() from vfs_coredump()
coredump: mark struct mm_struct as const
coredump: pass struct linux_binfmt as const
coredump: move revert_cred() before coredump_cleanup()
sev-dev: use override credential guards
sev-dev: use prepare credential guard
sev-dev: use guard for path
cred: add prepare credential guard
net/dns_resolver: use credential guards in dns_query()
cgroup: use credential guards in cgroup_attach_permissions()
act: use credential guards in acct_write_process()
smb: use credential guards in cifs_get_spnego_key()
nfs: use credential guards in nfs_idmap_get_key()
nfs: use credential guards in nfs_local_call_write()
nfs: use credential guards in nfs_local_call_read()
erofs: use credential guards
...
Fix all kernel-doc warnings in rnbd-proto.h:
- use correct enum name in kdoc comment
- mark several struct members as "/* private: */" so that no kdoc is
required for them
- don't use "/**" for a non-kernel-doc comment
- use the correct struct member name for "dev_name"
- use " *" for a blank kernel-doc line
Fixes these warnings:
Warning: drivers/block/rnbd/rnbd-proto.h:41 expecting prototype for
enum rnbd_msg_types. Prototype was for enum rnbd_msg_type instead
Warning: drivers/block/rnbd/rnbd-proto.h:50 struct member '__padding'
not described in 'rnbd_msg_hdr'
Warning: drivers/block/rnbd/rnbd-proto.h:53 This comment starts with
'/**', but isn't a kernel-doc comment.
* We allow to map RO many times and RW only once. We allow to map yet another
Warning: drivers/block/rnbd/rnbd-proto.h:81 struct member 'reserved'
not described in 'rnbd_msg_sess_info'
Warning: drivers/block/rnbd/rnbd-proto.h:92 struct member 'reserved'
not described in 'rnbd_msg_sess_info_rsp'
Warning: drivers/block/rnbd/rnbd-proto.h:107 struct member 'resv1'
not described in 'rnbd_msg_open'
Warning: drivers/block/rnbd/rnbd-proto.h:107 struct member 'dev_name'
not described in 'rnbd_msg_open'
Warning: drivers/block/rnbd/rnbd-proto.h:107 struct member 'reserved'
not described in 'rnbd_msg_open'
Warning: drivers/block/rnbd/rnbd-proto.h:158 struct member 'reserved'
not described in 'rnbd_msg_open_rsp'
Warning: drivers/block/rnbd/rnbd-proto.h:189 bad line:
Signed-off-by: Randy Dunlap <rdunlap@infradead.org>
Acked-by: Jack Wang <jinpu.wang@ionos.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
The spelling of the word "relases" is incorrect; it should be "releases".
Link: https://lkml.kernel.org/r/20251125020522.1913-1-chuguangqing@inspur.com
Signed-off-by: Chu Guangqing <chuguangqing@inspur.com>
Reviewed-by: Sergey Senozhatsky <senozhatsky@chromium.org>
Cc: Jens Axboe <axboe@kernel.dk>
Cc: Minchan Kim <minchan@kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Add helper __ublk_fetch() for refactoring ublk_fetch().
Meantime move ublk_config_io_buf() out of __ublk_fetch() to make
the code structure cleaner.
Reviewed-by: Caleb Sander Mateos <csander@purestorage.com>
Signed-off-by: Ming Lei <ming.lei@redhat.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
Pass const pointer to ublk_queue_is_zoned() because it is readonly.
Reviewed-by: Caleb Sander Mateos <csander@purestorage.com>
Signed-off-by: Ming Lei <ming.lei@redhat.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
Refactor auto buffer register code and prepare for supporting batch IO
feature, and the main motivation is to put 'ublk_io' operation code
together, so that per-io lock can be applied for the code block.
The key changes are:
- Rename ublk_auto_buf_reg() as ublk_do_auto_buf_reg()
- Introduce an enum `auto_buf_reg_res` to represent the result of
the buffer registration attempt (FAIL, FALLBACK, OK).
- Split the existing `ublk_do_auto_buf_reg` function into two:
- `__ublk_do_auto_buf_reg`: Performs the actual buffer registration
and returns the `auto_buf_reg_res` status.
- `ublk_do_auto_buf_reg`: A wrapper that calls the internal function
and handles the I/O preparation based on the result.
- Introduce `ublk_prep_auto_buf_reg_io` to encapsulate the logic for
preparing the I/O for completion after buffer registration.
- Pass the `tag` directly to `ublk_auto_buf_reg_fallback` to avoid
recalculating it.
This refactoring makes the control flow clearer and isolates the different
stages of the auto buffer registration process.
Reviewed-by: Caleb Sander Mateos <csander@purestorage.com>
Signed-off-by: Ming Lei <ming.lei@redhat.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
Add `union ublk_io_buf` for naming the anonymous union of struct ublk_io's
addr and buf fields, meantime apply it to `struct ublk_io` for storing either
ublk auto buffer register data or ublk server io buffer address.
The union uses clear field names:
- `addr`: for regular ublk server io buffer addresses
- `auto_reg`: for ublk auto buffer registration data
This eliminates confusing access patterns and improves code readability.
Reviewed-by: Caleb Sander Mateos <csander@purestorage.com>
Signed-off-by: Ming Lei <ming.lei@redhat.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
Add parameter `struct io_uring_cmd *` to ublk_prep_auto_buf_reg() and
prepare for reusing this helper for the coming UBLK_BATCH_IO feature,
which can fetch & commit one batch of io commands via single uring_cmd.
Reviewed-by: Caleb Sander Mateos <csander@purestorage.com>
Signed-off-by: Ming Lei <ming.lei@redhat.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
ublk_ch_uring_cmd_local() may jump to the out label before
initialising the io pointer. This will cause trouble if DEBUG is
defined, because the pr_devel() call dereferences io. Clang reports:
drivers/block/ublk_drv.c:2403:6: error: variable 'io' is used uninitialized whenever 'if' condition is true [-Werror,-Wsometimes-uninitialized]
2403 | if (tag >= ub->dev_info.queue_depth)
| ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
drivers/block/ublk_drv.c:2492:32: note: uninitialized use occurs here
2492 | __func__, cmd_op, tag, ret, io->flags);
|
Fix this by initialising io to NULL and checking it before
dereferencing it.
Signed-off-by: Kevin Brodsky <kevin.brodsky@arm.com>
Fixes: 71f28f3136 ("ublk_drv: add io_uring based userspace block driver")
Reviewed-by: Caleb Sander Mateos <csander@purestorage.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
This reverts commit f43fdeb9a3, reversing
changes made to 2c6d792d4b.
There are concerns that doing inline submits can cause excessive
stack usage, particularly when going back into the filesystem. Revert
the loop dio nowait change for now.
Link: https://lore.kernel.org/linux-block/aSP3SG_KaROJTBHx@infradead.org/
Signed-off-by: Jens Axboe <axboe@kernel.dk>
When the page size exceeds 4KB, if bd_wb_limit is set to a value that is
not aligned with the page size, it will cause a numerical wrap-around
issue for bd_wb_limit. For example, when the page size is set to 16KB and
bd_wb_limit is set to 3, after one write-back operation, the value of
bd_wb_limit will become -1. More seriously, since bd_wb_limit is an
unsigned number, its value may become as large as 2^64 - 1.
The core reason for this problem is that the unit of bd_wb_limit is 4KB.
For example, when a write-back occurs on a system with a page size of
16KB, 4 needs to be subtracted from bd_wb_limit. This operation takes
place in the zram_account_writeback_submit function.
This patch fixes the issue by limiting bd_wb_limit to be an integer
multiple of PAGE_SIZE / 4096.
Link: https://lkml.kernel.org/r/tencent_5936CFE72BAB2BA76887BB69DCC1B5E67C05@qq.com
Fixes: 1d69a3f8ae ("zram: idle writeback fixes and cleanup")
Signed-off-by: Yuwen Chen <ywen.chen@foxmail.com>
Acked-by: Sergey Senozhatsky <senozhatsky@chromium.org>
Cc: Brian Geffon <bgeffon@google.com>
Cc: Minchan Kim <minchan@kernel.org>
Cc: Richard Chang <richardycc@google.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Read slot's block id under slot-lock. We release the slot-lock for bdev
read so, technically, slot still can get freed in the meantime, but at
least we will read bdev block (page) that holds previous know slot data,
not from slot->handle bdev block, which can be anything at that point.
Link: https://lkml.kernel.org/r/20251122074029.3948921-7-senozhatsky@chromium.org
Signed-off-by: Sergey Senozhatsky <senozhatsky@chromium.org>
Cc: Brian Geffon <bgeffon@google.com>
Cc: Minchan Kim <minchan@google.com>
Cc: Richard Chang <richardycc@google.com>
Cc: Yuwen Chen <ywen.chen@foxmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
First, writeback bdev ->bitmap bits are set only from one context, as we
can have only one single task performing writeback, so we cannot race with
anything else. Remove retry path.
Second, we always check ZRAM_WB flag to distinguish writtenback slots, so
we should not confuse 0 bdev block index and 0 handle. We can use first
bdev block (0 bit) for writeback as well.
While at it, give functions slightly more accurate names, as we don't
alloc/free anything there, we reserve a block for async writeback or
release the block.
Link: https://lkml.kernel.org/r/20251122074029.3948921-6-senozhatsky@chromium.org
Signed-off-by: Sergey Senozhatsky <senozhatsky@chromium.org>
Reviewed-by: Brian Geffon <bgeffon@google.com>
Cc: Minchan Kim <minchan@google.com>
Cc: Richard Chang <richardycc@google.com>
Cc: Yuwen Chen <ywen.chen@foxmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
We don't need wb_limit_lock. Writeback limit setters take an exclusive
write zram init_lock, while wb_limit modifications happen only from a
single task and under zram read init_lock. No concurrent wb_limit
modifications are possible (we permit only one post-processing task at a
time). Add lockdep assertions to wb_limit mutators.
While at it, fixup coding styles.
Link: https://lkml.kernel.org/r/20251122074029.3948921-5-senozhatsky@chromium.org
Signed-off-by: Sergey Senozhatsky <senozhatsky@chromium.org>
Reviewed-by: Brian Geffon <bgeffon@google.com>
Cc: Minchan Kim <minchan@google.com>
Cc: Richard Chang <richardycc@google.com>
Cc: Yuwen Chen <ywen.chen@foxmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Introduce writeback_batch_size device attribute so that the maximum number
of in-flight writeback bio requests can be configured at run-time
per-device. This essentially enables batched bio writeback.
Link: https://lkml.kernel.org/r/20251122074029.3948921-3-senozhatsky@chromium.org
Signed-off-by: Sergey Senozhatsky <senozhatsky@chromium.org>
Reviewed-by: Brian Geffon <bgeffon@google.com>
Cc: Minchan Kim <minchan@google.com>
Cc: Richard Chang <richardycc@google.com>
Cc: Yuwen Chen <ywen.chen@foxmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Patch series "zram: introduce writeback bio batching", v6.
As writeback is becoming more and more common the longstanding limitations
of zram writeback throughput are becoming more visible. Introduce
writeback bio batching so that multiple writeback bios can be processed
simultaneously.
This patch (of 6):
As was stated in a comment [1] a single page writeback IO is not
efficient, but it works. It's time to address this throughput limitation
as writeback becomes used more often. Introduce batched (multiple) bio
writeback support to take advantage of parallel requests processing and
better requests scheduling.
Approach used in this patch doesn't use a dedicated kthread like in [2],
or blk-plug like in [3]. Dedicated kthread adds complexity, which can be
avoided. Apart from that not all zram setups use writeback, so having
numerous per-device kthreads (on systems that create multiple zram
devices) hanging around is not the most optimal thing to do. blk-plug, on
the other hand, works best when request are sequential, which doesn't
particularly fit zram writebck IO patterns: zram writeback IO patterns are
expected to be random, due to how bdev block reservation/release are
handled. blk-plug approach also works in cycles: idle IO, when zram sets
up requests in a batch, is followed by bursts of IO, when zram submits the
entire batch.
Instead we use a batch of requests and submit new bio as soon as one of
the in-flight requests completes.
For the time being the writeback batch size (maximum number of in-flight
bio requests) is set to 32 for all devices. A follow up patch adds a
writeback_batch_size device attribute, so the batch size becomes run-time
configurable.
Link: https://lkml.kernel.org/r/20251122074029.3948921-1-senozhatsky@chromium.org
Link: https://lkml.kernel.org/r/20251122074029.3948921-2-senozhatsky@chromium.org
Link: https://lore.kernel.org/all/20181203024045.153534-6-minchan@kernel.org/ [1]
Link: https://lore.kernel.org/all/20250731064949.1690732-1-richardycc@google.com/ [2]
Link: https://lore.kernel.org/all/tencent_78FC2C4FE16BA1EBAF0897DB60FCD675ED05@qq.com/ [3]
Signed-off-by: Sergey Senozhatsky <senozhatsky@chromium.org>
Co-developed-by: Yuwen Chen <ywen.chen@foxmail.com>
Co-developed-by: Richard Chang <richardycc@google.com>
Suggested-by: Minchan Kim <minchan@google.com>
Cc: Brian Geffon <bgeffon@google.com>
Cc: Richard Chang <richardycc@google.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
The zloop driver advertises REQ_NOWAIT support through BLK_FEAT_NOWAIT
(enabled by default for all blk-mq devices), and honors the nowait
behavior throughout zloop_queue_rq().
However, actual I/O to the backing file is performed in a workqueue,
where blocking is allowed.
To avoid imposing unnecessary non-blocking constraints in this blocking
context, clear the REQ_NOWAIT flag before processing the request in the
workqueue context.
Signed-off-by: Chaitanya Kulkarni <ckulkarnilinux@gmail.com>
Reviewed-by: Damien Le Moal <dlemoal@kernel.org>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
The loop driver advertises REQ_NOWAIT support through BLK_FEAT_NOWAIT
(enabled by default for all blk-mq devices), and honors the nowait
behavior throughout loop_queue_rq().
However, actual I/O to the backing file is performed in a workqueue,
where blocking is allowed.
To avoid imposing unnecessary non-blocking constraints in this blocking
context, clear the REQ_NOWAIT flag before processing the request in the
workqueue context.
Signed-off-by: Chaitanya Kulkarni <ckulkarnilinux@gmail.com>
Reviewed-by: Damien Le Moal <dlemoal@kernel.org>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
While commit cf28f6f923 ("zloop: fail zone append operations that are
targeting full zones") added a check in zloop_rw() that a zone append is
not issued to a full zone, commit e3a96ca904 ("zloop: simplify checks
for writes to sequential zones") inadvertently removed the check to
verify that there is enough unwritten space in a zone for an incoming
zone append opration.
Re-add this check in zloop_rw() to make sure we do not write beyond the
end of a zone. Of note is that this same check is already present in the
function zloop_set_zone_append_sector() when ordered zone append is in
use.
Reported-by: Hans Holmberg <Hans.Holmberg@wdc.com>
Fixes: e3a96ca904 ("zloop: simplify checks for writes to sequential zones")
Signed-off-by: Damien Le Moal <dlemoal@kernel.org>
Reviewed-by: Hans Holmberg <hans.holmberg@wdc.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
Add hint for using IOCB_NOWAIT to handle loop aio command for avoiding
to cause write(especially randwrite) perf regression on sparse backed file.
Try IOCB_NOWAIT in the following situations:
- backing file is block device
OR
- READ aio command
OR
- there isn't any queued blocking async WRITEs, because NOWAIT won't cause
contention with blocking WRITE, which often implies exclusive lock
With this simple policy, perf regression of randwrite/write on sparse
backing file is fixed.
Link: https://lore.kernel.org/dm-devel/7d6ae2c9-df8e-50d0-7ad6-b787cb3cfab4@redhat.com/
Signed-off-by: Ming Lei <ming.lei@redhat.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
Try to handle loop aio command via NOWAIT IO first, then we can avoid to
queue the aio command into workqueue. This is usually one big win in
case that FS block mapping is stable, Mikulas verified [1] that this way
improves IO perf by close to 5X in 12jobs sequential read/write test,
in which FS block mapping is just stable.
Fallback to workqueue in case of -EAGAIN. This way may bring a little
cost from the 1st retry, but when running the following write test over
loop/sparse_file, the actual effect on randwrite is obvious:
```
truncate -s 4G 1.img #1.img is created on XFS/virtio-scsi
losetup -f 1.img --direct-io=on
fio --direct=1 --bs=4k --runtime=40 --time_based --numjobs=1 --ioengine=libaio \
--iodepth=16 --group_reporting=1 --filename=/dev/loop0 -name=job --rw=$RW
```
- RW=randwrite: obvious IOPS drop observed
- RW=write: a little drop(%5 - 10%)
This perf drop on randwrite over sparse file will be addressed in the
following patch.
BLK_MQ_F_BLOCKING has to be set for calling into .read_iter() or .write_iter()
which might sleep even though it is NOWAIT, and the only effect is that rcu read
lock is replaced with srcu read lock.
Link: https://lore.kernel.org/linux-block/a8e5c76a-231f-07d1-a394-847de930f638@redhat.com/ [1]
Signed-off-by: Ming Lei <ming.lei@redhat.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
Move loop command blkcg/memcg initialization into loop_queue_work,
and prepare for supporting to handle loop io command by IOCB_NOWAIT.
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Ming Lei <ming.lei@redhat.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
Refactor lo_rw_aio() by extracting the I/O submission logic into a new
helper function lo_submit_rw_aio(). This further improves code organization
by separating the I/O preparation, submission, and completion handling into
distinct phases.
Prepare for using NOWAIT to improve loop performance.
Signed-off-by: Ming Lei <ming.lei@redhat.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
Ming Lei
Seamus Connor
Alejandro Colomar
Heiko Carstens
Sergey Senozhatsky
Richard Chang
Linus Torvalds
Chaitanya Kulkarni
Nilay Shroff
Yoav Cohen
Caleb Sander Mateos
Stanley Zhang
Jens Axboe
Tetsuo Handa
Raphael Pinsonneault-Thibeault
Md Haris Iqbal
Florian-Ewald Mueller
Jack Wang
Zhu Yanjun
Christophe JAILLET
Thorsten Blum
Tamir Duberstein
Dan Carpenter
Thomas Fourier
Yongpeng Yang
Ilya Dryomov
Randy Dunlap
Chu Guangqing
Kevin Brodsky
Yuwen Chen
Damien Le Moal