Commit Graph

26 Commits

Author SHA1 Message Date
Josh Poimboeuf ca653464dd objtool: Add verbose option for disassembling affected functions
When a warning is associated with a function, add an option to
disassemble that function.

This makes it easier for reporters to submit the information needed to
diagnose objtool warnings.

Reviewed-by: Miroslav Benes <mbenes@suse.cz>
Link: https://lore.kernel.org/r/dd0fe13428ede186f09c74059a8001f4adcea5fc.1681853186.git.jpoimboe@kernel.org
Signed-off-by: Josh Poimboeuf <jpoimboe@kernel.org>
2023-05-16 06:31:51 -07:00
Thomas Weißschuh cfd66e8179 objtool: Make struct check_options static
It is not used outside of builtin-check.c.

Also remove the unused declaration from builtin.h .

Signed-off-by: Thomas Weißschuh <linux@weissschuh.net>
Link: https://lore.kernel.org/r/20221216-objtool-memory-v2-2-17968f85a464@weissschuh.net
Signed-off-by: Josh Poimboeuf <jpoimboe@kernel.org>
2023-02-01 09:15:23 -08:00
Linus Torvalds 5f6e430f93 powerpc updates for 6.2
- Add powerpc qspinlock implementation optimised for large system scalability and
    paravirt. See the merge message for more details.
 
  - Enable objtool to be built on powerpc to generate mcount locations.
 
  - Use a temporary mm for code patching with the Radix MMU, so the writable mapping is
    restricted to the patching CPU.
 
  - Add an option to build the 64-bit big-endian kernel with the ELFv2 ABI.
 
  - Sanitise user registers on interrupt entry on 64-bit Book3S.
 
  - Many other small features and fixes.
 
 Thanks to: Aboorva Devarajan, Angel Iglesias, Benjamin Gray, Bjorn Helgaas, Bo Liu, Chen
 Lifu, Christoph Hellwig, Christophe JAILLET, Christophe Leroy, Christopher M. Riedl, Colin
 Ian King, Deming Wang, Disha Goel, Dmitry Torokhov, Finn Thain, Geert Uytterhoeven,
 Gustavo A. R. Silva, Haowen Bai, Joel Stanley, Jordan Niethe, Julia Lawall, Kajol Jain,
 Laurent Dufour, Li zeming, Miaoqian Lin, Michael Jeanson, Nathan Lynch, Naveen N. Rao,
 Nayna Jain, Nicholas Miehlbradt, Nicholas Piggin, Pali Rohár, Randy Dunlap, Rohan McLure,
 Russell Currey, Sathvika Vasireddy, Shaomin Deng, Stephen Kitt, Stephen Rothwell, Thomas
 Weißschuh, Tiezhu Yang, Uwe Kleine-König, Xie Shaowen, Xiu Jianfeng, XueBing Chen, Yang
 Yingliang, Zhang Jiaming, ruanjinjie, Jessica Yu, Wolfram Sang.
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Merge tag 'powerpc-6.2-1' of git://git.kernel.org/pub/scm/linux/kernel/git/powerpc/linux

Pull powerpc updates from Michael Ellerman:

 - Add powerpc qspinlock implementation optimised for large system
   scalability and paravirt. See the merge message for more details

 - Enable objtool to be built on powerpc to generate mcount locations

 - Use a temporary mm for code patching with the Radix MMU, so the
   writable mapping is restricted to the patching CPU

 - Add an option to build the 64-bit big-endian kernel with the ELFv2
   ABI

 - Sanitise user registers on interrupt entry on 64-bit Book3S

 - Many other small features and fixes

Thanks to Aboorva Devarajan, Angel Iglesias, Benjamin Gray, Bjorn
Helgaas, Bo Liu, Chen Lifu, Christoph Hellwig, Christophe JAILLET,
Christophe Leroy, Christopher M. Riedl, Colin Ian King, Deming Wang,
Disha Goel, Dmitry Torokhov, Finn Thain, Geert Uytterhoeven, Gustavo A.
R. Silva, Haowen Bai, Joel Stanley, Jordan Niethe, Julia Lawall, Kajol
Jain, Laurent Dufour, Li zeming, Miaoqian Lin, Michael Jeanson, Nathan
Lynch, Naveen N. Rao, Nayna Jain, Nicholas Miehlbradt, Nicholas Piggin,
Pali Rohár, Randy Dunlap, Rohan McLure, Russell Currey, Sathvika
Vasireddy, Shaomin Deng, Stephen Kitt, Stephen Rothwell, Thomas
Weißschuh, Tiezhu Yang, Uwe Kleine-König, Xie Shaowen, Xiu Jianfeng,
XueBing Chen, Yang Yingliang, Zhang Jiaming, ruanjinjie, Jessica Yu,
and Wolfram Sang.

* tag 'powerpc-6.2-1' of git://git.kernel.org/pub/scm/linux/kernel/git/powerpc/linux: (181 commits)
  powerpc/code-patching: Fix oops with DEBUG_VM enabled
  powerpc/qspinlock: Fix 32-bit build
  powerpc/prom: Fix 32-bit build
  powerpc/rtas: mandate RTAS syscall filtering
  powerpc/rtas: define pr_fmt and convert printk call sites
  powerpc/rtas: clean up includes
  powerpc/rtas: clean up rtas_error_log_max initialization
  powerpc/pseries/eeh: use correct API for error log size
  powerpc/rtas: avoid scheduling in rtas_os_term()
  powerpc/rtas: avoid device tree lookups in rtas_os_term()
  powerpc/rtasd: use correct OF API for event scan rate
  powerpc/rtas: document rtas_call()
  powerpc/pseries: unregister VPA when hot unplugging a CPU
  powerpc/pseries: reset the RCU watchdogs after a LPM
  powerpc: Take in account addition CPU node when building kexec FDT
  powerpc: export the CPU node count
  powerpc/cpuidle: Set CPUIDLE_FLAG_POLLING for snooze state
  powerpc/dts/fsl: Fix pca954x i2c-mux node names
  cxl: Remove unnecessary cxl_pci_window_alignment()
  selftests/powerpc: Fix resource leaks
  ...
2022-12-19 07:13:33 -06:00
Sathvika Vasireddy 280981d699 objtool: Add --mnop as an option to --mcount
Some architectures (powerpc) may not support ftrace locations being nop'ed
out at build time. Introduce CONFIG_HAVE_OBJTOOL_NOP_MCOUNT for objtool, as
a means for architectures to enable nop'ing of ftrace locations. Add --mnop
as an option to objtool --mcount, to indicate support for the same.

Also, make sure that --mnop can be passed as an option to objtool only when
--mcount is passed.

Tested-by: Naveen N. Rao <naveen.n.rao@linux.vnet.ibm.com>
Reviewed-by: Naveen N. Rao <naveen.n.rao@linux.vnet.ibm.com>
Acked-by: Josh Poimboeuf <jpoimboe@kernel.org>
Reviewed-by: Christophe Leroy <christophe.leroy@csgroup.eu>
Signed-off-by: Sathvika Vasireddy <sv@linux.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/20221114175754.1131267-12-sv@linux.ibm.com
2022-11-18 19:00:16 +11:00
Peter Zijlstra 9a479f766b objtool: Add --cfi to generate the .cfi_sites section
Add the location of all __cfi_##name symbols (as generated by kCFI) to
a section such that we might re-write things at kernel boot.

Notably; boot time re-hashing and FineIBT are the intended use of
this.

Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Link: https://lore.kernel.org/r/20221027092842.568039454@infradead.org
2022-11-01 13:44:10 +01:00
Peter Zijlstra 9f2899fe36 objtool: Add option to generate prefix symbols
When code is compiled with:

  -fpatchable-function-entry=${PADDING_BYTES},${PADDING_BYTES}

functions will have PADDING_BYTES of NOP in front of them. Unwinders
and other things that symbolize code locations will typically
attribute these bytes to the preceding function.

Given that these bytes nominally belong to the following symbol this
mis-attribution is confusing.

Inspired by the fact that CFI_CLANG emits __cfi_##name symbols to
claim these bytes, allow objtool to emit __pfx_##name symbols to do
the same.

Therefore add the objtool --prefix=N argument, to conditionally place
a __pfx_##name symbol at N bytes ahead of symbol 'name' when: all
these preceding bytes are NOP and name-N is an instruction boundary.

Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Tested-by: Yujie Liu <yujie.liu@intel.com>
Link: https://lkml.kernel.org/r/20221028194453.526899822@infradead.org
2022-11-01 13:44:09 +01:00
Peter Zijlstra 0c0a6d8934 objtool: Add --hacks=skylake
Make the call/func sections selectable via the --hacks option.

Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Link: https://lore.kernel.org/r/20220915111146.120821440@infradead.org
2022-10-17 16:41:07 +02:00
Peter Zijlstra f43b9876e8 x86/retbleed: Add fine grained Kconfig knobs
Do fine-grained Kconfig for all the various retbleed parts.

NOTE: if your compiler doesn't support return thunks this will
silently 'upgrade' your mitigation to IBPB, you might not like this.

Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Signed-off-by: Borislav Petkov <bp@suse.de>
2022-06-29 17:43:41 +02:00
Peter Zijlstra a09a6e2399 objtool: Add entry UNRET validation
Since entry asm is tricky, add a validation pass that ensures the
retbleed mitigation has been done before the first actual RET
instruction.

Entry points are those that either have UNWIND_HINT_ENTRY, which acts
as UNWIND_HINT_EMPTY but marks the instruction as an entry point, or
those that have UWIND_HINT_IRET_REGS at +0.

This is basically a variant of validate_branch() that is
intra-function and it will simply follow all branches from marked
entry points and ensures that all paths lead to ANNOTATE_UNRET_END.

If a path hits RET or an indirection the path is a fail and will be
reported.

There are 3 ANNOTATE_UNRET_END instances:

 - UNTRAIN_RET itself
 - exception from-kernel; this path doesn't need UNTRAIN_RET
 - all early exceptions; these also don't need UNTRAIN_RET

Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Signed-off-by: Borislav Petkov <bp@suse.de>
Reviewed-by: Josh Poimboeuf <jpoimboe@kernel.org>
Signed-off-by: Borislav Petkov <bp@suse.de>
2022-06-27 10:34:00 +02:00
Josh Poimboeuf 753da4179d objtool: Remove --lto and --vmlinux in favor of --link
The '--lto' option is a confusing way of telling objtool to do stack
validation despite it being a linked object.  It's no longer needed now
that an explicit '--stackval' option exists.  The '--vmlinux' option is
also redundant.

Remove both options in favor of a straightforward '--link' option which
identifies a linked object.

Also, implicitly set '--link' with a warning if the user forgets to do
so and we can tell that it's a linked object.  This makes it easier for
manual vmlinux runs.

Signed-off-by: Josh Poimboeuf <jpoimboe@redhat.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Reviewed-by: Miroslav Benes <mbenes@suse.cz>
Link: https://lkml.kernel.org/r/dcd3ceffd15a54822c6183e5766d21ad06082b45.1650300597.git.jpoimboe@redhat.com
2022-04-22 12:32:05 +02:00
Josh Poimboeuf 22102f4559 objtool: Make noinstr hacks optional
Objtool has some hacks in place to workaround toolchain limitations
which otherwise would break no-instrumentation rules.  Make the hacks
explicit (and optional for other arches) by turning it into a cmdline
option and kernel config option.

Signed-off-by: Josh Poimboeuf <jpoimboe@redhat.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Reviewed-by: Miroslav Benes <mbenes@suse.cz>
Link: https://lkml.kernel.org/r/b326eeb9c33231b9dfbb925f194ed7ee40edcd7c.1650300597.git.jpoimboe@redhat.com
2022-04-22 12:32:04 +02:00
Josh Poimboeuf 4ab7674f59 objtool: Make jump label hack optional
Objtool secretly does a jump label hack to overcome the limitations of
the toolchain.  Make the hack explicit (and optional for other arches)
by turning it into a cmdline option and kernel config option.

Signed-off-by: Josh Poimboeuf <jpoimboe@redhat.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Reviewed-by: Miroslav Benes <mbenes@suse.cz>
Link: https://lkml.kernel.org/r/3bdcbfdd27ecb01ddec13c04bdf756a583b13d24.1650300597.git.jpoimboe@redhat.com
2022-04-22 12:32:04 +02:00
Josh Poimboeuf 26e176896a objtool: Make static call annotation optional
As part of making objtool more modular, put the existing static call
code behind a new '--static-call' option.

Signed-off-by: Josh Poimboeuf <jpoimboe@redhat.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Reviewed-by: Miroslav Benes <mbenes@suse.cz>
Link: https://lkml.kernel.org/r/d59ac57ef3d6d8380cdce20322314c9e2e556750.1650300597.git.jpoimboe@redhat.com
2022-04-22 12:32:03 +02:00
Josh Poimboeuf 7206447496 objtool: Make stack validation frame-pointer-specific
Now that CONFIG_STACK_VALIDATION is frame-pointer specific, do the same
for the '--stackval' option.  Now the '--no-fp' option is redundant and
can be removed.

Signed-off-by: Josh Poimboeuf <jpoimboe@redhat.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Reviewed-by: Miroslav Benes <mbenes@suse.cz>
Link: https://lkml.kernel.org/r/f563fa064b3b63d528de250c72012d49e14742a3.1650300597.git.jpoimboe@redhat.com
2022-04-22 12:32:03 +02:00
Josh Poimboeuf 7dce62041a objtool: Make stack validation optional
Make stack validation an explicit cmdline option so that individual
objtool features can be enabled individually by other arches.

Signed-off-by: Josh Poimboeuf <jpoimboe@redhat.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Reviewed-by: Miroslav Benes <mbenes@suse.cz>
Link: https://lkml.kernel.org/r/52da143699574d756e65ca4c9d4acaffe9b0fe5f.1650300597.git.jpoimboe@redhat.com
2022-04-22 12:32:02 +02:00
Josh Poimboeuf 99c0beb547 objtool: Add option to print section addresses
To help prevent objtool users from having to do math to convert function
addresses to section addresses, and to help out with finding data
addresses reported by IBT validation, add an option to print the section
address in addition to the function address.

Normal:

  vmlinux.o: warning: objtool: fixup_exception()+0x2d1: unreachable instruction

With '--sec-address':

  vmlinux.o: warning: objtool: fixup_exception()+0x2d1 (.text+0x76c51): unreachable instruction

Suggested-by: Nick Desaulniers <ndesaulniers@google.com>
Signed-off-by: Josh Poimboeuf <jpoimboe@redhat.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Reviewed-by: Miroslav Benes <mbenes@suse.cz>
Link: https://lkml.kernel.org/r/2cea4d5299d53d1a4c09212a6ad7820aa46fda7a.1650300597.git.jpoimboe@redhat.com
2022-04-22 12:32:02 +02:00
Josh Poimboeuf b51277eb97 objtool: Ditch subcommands
Objtool has a fairly singular focus.  It runs on object files and does
validations and transformations which can be combined in various ways.
The subcommand model has never been a good fit, making it awkward to
combine and remove options.

Remove the "check" and "orc" subcommands in favor of a more traditional
cmdline option model.  This makes it much more flexible to use, and
easier to port individual features to other arches.

Signed-off-by: Josh Poimboeuf <jpoimboe@redhat.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Reviewed-by: Miroslav Benes <mbenes@suse.cz>
Link: https://lkml.kernel.org/r/5c61ebf805e90aefc5fa62bc63468ffae53b9df6.1650300597.git.jpoimboe@redhat.com
2022-04-22 12:32:01 +02:00
Josh Poimboeuf 2daf7faba7 objtool: Reorganize cmdline options
Split the existing options into two groups: actions, which actually do
something; and options, which modify the actions in some way.

Also there's no need to have short flags for all the non-action options.
Reserve short flags for the more important actions.

While at it:

- change a few of the short flags to be more intuitive

- make option descriptions more consistently descriptive

- sort options in the source like they are when printed

- move options to a global struct

Signed-off-by: Josh Poimboeuf <jpoimboe@redhat.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Reviewed-by: Miroslav Benes <mbenes@suse.cz>
Link: https://lkml.kernel.org/r/9dcaa752f83aca24b1b21f0b0eeb28a0c181c0b0.1650300597.git.jpoimboe@redhat.com
2022-04-22 12:32:01 +02:00
Peter Zijlstra 08f87a93c8 objtool: Validate IBT assumptions
Intel IBT requires that every indirect JMP/CALL targets an ENDBR
instructions, failing this #CP happens and we die. Similarly, all
exception entries should be ENDBR.

Find all code relocations and ensure they're either an ENDBR
instruction or ANNOTATE_NOENDBR. For the exceptions look for
UNWIND_HINT_IRET_REGS at sym+0 not being ENDBR.

Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Acked-by: Josh Poimboeuf <jpoimboe@redhat.com>
Link: https://lore.kernel.org/r/20220308154319.705110141@infradead.org
2022-03-15 10:32:46 +01:00
Peter Zijlstra 53f7109ef9 objtool: Rename --duplicate to --lto
In order to prepare for LTO like objtool runs for modules, rename the
duplicate argument to lto.

Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Acked-by: Josh Poimboeuf <jpoimboe@redhat.com>
Link: https://lore.kernel.org/r/20220308154319.172584233@infradead.org
2022-03-15 10:32:42 +01:00
Peter Zijlstra f2d3a25089 objtool: Add --dry-run
Add a --dry-run argument to skip writing the modifications. This is
convenient for debugging.

Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Reviewed-by: Kees Cook <keescook@chromium.org>
Reviewed-by: Miroslav Benes <mbenes@suse.cz>
Acked-by: Josh Poimboeuf <jpoimboe@redhat.com>
Link: https://lore.kernel.org/r/20220308154317.282720146@infradead.org
2022-03-15 10:32:32 +01:00
Peter Zijlstra 1cc1e4c8aa objtool: Add straight-line-speculation validation
Teach objtool to validate the straight-line-speculation constraints:

 - speculation trap after indirect calls
 - speculation trap after RET

Notable: when an instruction is annotated RETPOLINE_SAFE, indicating
  speculation isn't a problem, also don't care about sls for that
  instruction.

Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Signed-off-by: Borislav Petkov <bp@suse.de>
Link: https://lore.kernel.org/r/20211204134908.023037659@infradead.org
2021-12-08 19:26:50 +01:00
Peter Zijlstra a2f605f9ff objtool: Collate parse_options() users
Ensure there's a single place that parses check_options, in
preparation for extending where to get options from.

Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Acked-by: Josh Poimboeuf <jpoimboe@redhat.com>
Link: https://lkml.kernel.org/r/20210226110004.193108106@infradead.org
2021-03-06 12:44:23 +01:00
Peter Zijlstra 8ad15c6900 objtool: Add --backup
Teach objtool to write backups files, such that it becomes easier to
see what objtool did to the object file.

Backup files will be ${name}.orig.

Suggested-by: Borislav Petkov <bp@alien8.de>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Acked-by: Borislav Petkov <bp@suse.de>
Acked-by: Josh Poimboeuf <jpoimboe@redhat.com>
Link: https://lkml.kernel.org/r/YD4obT3aoXPWl7Ax@hirez.programming.kicks-ass.net
2021-03-06 12:44:23 +01:00
Linus Torvalds 414eece95b clang-lto for v5.12-rc1 (part2)
- Generate __mcount_loc in objtool (Peter Zijlstra)
 - Support running objtool against vmlinux.o (Sami Tolvanen)
 - Clang LTO enablement for x86 (Sami Tolvanen)
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Merge tag 'clang-lto-v5.12-rc1-part2' of git://git.kernel.org/pub/scm/linux/kernel/git/kees/linux

Pull more clang LTO updates from Kees Cook:
 "Clang LTO x86 enablement.

  Full disclosure: while this has _not_ been in linux-next (since it
  initially looked like the objtool dependencies weren't going to make
  v5.12), it has been under daily build and runtime testing by Sami for
  quite some time. These x86 portions have been discussed on lkml, with
  Peter, Josh, and others helping nail things down.

  The bulk of the changes are to get objtool working happily. The rest
  of the x86 enablement is very small.

  Summary:

   - Generate __mcount_loc in objtool (Peter Zijlstra)

   - Support running objtool against vmlinux.o (Sami Tolvanen)

   - Clang LTO enablement for x86 (Sami Tolvanen)"

Link: https://lore.kernel.org/lkml/20201013003203.4168817-26-samitolvanen@google.com/
Link: https://lore.kernel.org/lkml/cover.1611263461.git.jpoimboe@redhat.com/

* tag 'clang-lto-v5.12-rc1-part2' of git://git.kernel.org/pub/scm/linux/kernel/git/kees/linux:
  kbuild: lto: force rebuilds when switching CONFIG_LTO
  x86, build: allow LTO to be selected
  x86, cpu: disable LTO for cpu.c
  x86, vdso: disable LTO only for vDSO
  kbuild: lto: postpone objtool
  objtool: Split noinstr validation from --vmlinux
  x86, build: use objtool mcount
  tracing: add support for objtool mcount
  objtool: Don't autodetect vmlinux.o
  objtool: Fix __mcount_loc generation with Clang's assembler
  objtool: Add a pass for generating __mcount_loc
2021-02-23 15:13:45 -08:00
Vasily Gorbik 7786032e52 objtool: Rework header include paths
Currently objtool headers are being included either by their base name
or included via ../ from a parent directory. In case of a base name usage:

 #include "warn.h"
 #include "arch_elf.h"

it does not make it apparent from which directory the file comes from.
To make it slightly better, and actually to avoid name clashes some arch
specific files have "arch_" suffix. And files from an arch folder have
to revert to including via ../ e.g:
 #include "../../elf.h"

With additional architectures support and the code base growth there is
a need for clearer headers naming scheme for multiple reasons:
1. to make it instantly obvious where these files come from (objtool
   itself / objtool arch|generic folders / some other external files),
2. to avoid name clashes of objtool arch specific headers, potential
   obtool arch generic headers and the system header files (there is
   /usr/include/elf.h already),
3. to avoid ../ includes and improve code readability.
4. to give a warm fuzzy feeling to developers who are mostly kernel
   developers and are accustomed to linux kernel headers arranging
   scheme.

Doesn't this make it instantly obvious where are these files come from?

 #include <objtool/warn.h>
 #include <arch/elf.h>

And doesn't it look nicer to avoid ugly ../ includes? Which also
guarantees this is elf.h from the objtool and not /usr/include/elf.h.

 #include <objtool/elf.h>

This patch defines and implements new objtool headers arranging
scheme. Which is:
- all generic headers go to include/objtool (similar to include/linux)
- all arch headers go to arch/$(SRCARCH)/include/arch (to get arch
  prefix). This is similar to linux arch specific "asm/*" headers but we
  are not abusing "asm" name and calling it what it is. This also helps
  to prevent name clashes (arch is not used in system headers or kernel
  exports).

To bring objtool to this state the following things are done:
1. current top level tools/objtool/ headers are moved into
   include/objtool/ subdirectory,
2. arch specific headers, currently only arch/x86/include/ are moved into
   arch/x86/include/arch/ and were stripped of "arch_" suffix,
3. new -I$(srctree)/tools/objtool/include include path to make
   includes like <objtool/warn.h> possible,
4. rewriting file includes,
5. make git not to ignore include/objtool/ subdirectory.

Signed-off-by: Vasily Gorbik <gor@linux.ibm.com>
Acked-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Acked-by: Masami Hiramatsu <mhiramat@kernel.org>
Signed-off-by: Josh Poimboeuf <jpoimboe@redhat.com>
2021-01-13 18:13:14 -06:00