Commit graph android_kernel_sony_sdm845/tools/objtool
Message SHA1
objtool: Clobber user CFLAGS variable
commit f73b3cc39c84220e6dccd463b5c8279b03514646 upstream.

If the build user has the CFLAGS variable set in their environment,
objtool blindly appends to it, which can cause unexpected behavior.

Clobber CFLAGS to ensure consistent objtool compilation behavior.

Reported-by: Valdis Kletnieks <valdis.kletnieks@vt.edu>
Tested-by: Valdis Kletnieks <valdis.kletnieks@vt.edu>
Signed-off-by: Josh Poimboeuf <jpoimboe@redhat.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Link: https://lkml.kernel.org/r/83a276df209962e6058fcb6c615eef9d401c21bc.1567121311.git.jpoimboe@redhat.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
CC: Nathan Chancellor <natechancellor@gmail.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

Josh Poimboeuf   authored and   Greg Kroah-Hartman   commited 2019-10-05 12:30:08 +02:00
cb40b5b920
objtool: Add rewind_stack_do_exit() to the noreturn list
commit 4fa5ecda2bf96be7464eb406df8aba9d89260227 upstream.

This fixes the following warning seen on GCC 7.3:

  arch/x86/kernel/dumpstack.o: warning: objtool: oops_end() falls through to next function show_regs()

Reported-by: kbuild test robot <lkp@intel.com>
Signed-off-by: Josh Poimboeuf <jpoimboe@redhat.com>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Cc: Peter Zijlstra <peterz@infradead.org>
Link: https://lkml.kernel.org/r/3418ebf5a5a9f6ed7e80954c741c0b904b67b5dc.1554398240.git.jpoimboe@redhat.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

Josh Poimboeuf   authored and   Greg Kroah-Hartman   commited 2019-08-11 12:22:15 +02:00
180019b00c
objtool: Add machine_real_restart() to the noreturn list
commit 684fb246578b9e81fc7b4ca5c71eae22edb650b2 upstream.

machine_real_restart() is annotated as '__noreturn", so add it to the
objtool noreturn list.  This fixes the following warning with clang and
CONFIG_CC_OPTIMIZE_FOR_SIZE=y:

  arch/x86/kernel/reboot.o: warning: objtool: native_machine_emergency_restart() falls through to next function machine_power_off()

Reported-by: Matthias Kaehlcke <mka@chromium.org>
Signed-off-by: Josh Poimboeuf <jpoimboe@redhat.com>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Tested-by: Matthias Kaehlcke <mka@chromium.org>
Reviewed-by: Matthias Kaehlcke <mka@chromium.org>
Link: https://lkml.kernel.org/r/791712792aa4431bdd55bf1beb33a169ddf3b4a2.1529423255.git.jpoimboe@redhat.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

Josh Poimboeuf   authored and   Greg Kroah-Hartman   commited 2019-08-11 12:22:15 +02:00
495dace544
objtool: Support GCC 9 cold subfunction naming scheme
commit bcb6fb5da77c2a228adf07cc9cb1a0c2aa2001c6 upstream.

Starting with GCC 8, a lot of unlikely code was moved out of line to
"cold" subfunctions in .text.unlikely.

For example, the unlikely bits of:

  irq_do_set_affinity()

are moved out to the following subfunction:

  irq_do_set_affinity.cold.49()

Starting with GCC 9, the numbered suffix has been removed.  So in the
above example, the cold subfunction is instead:

  irq_do_set_affinity.cold()

Tweak the objtool subfunction detection logic so that it detects both
GCC 8 and GCC 9 naming schemes.

Reported-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Signed-off-by: Josh Poimboeuf <jpoimboe@redhat.com>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Tested-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Acked-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Link: https://lkml.kernel.org/r/015e9544b1f188d36a7f02fa31e9e95629aa5f50.1541040800.git.jpoimboe@redhat.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

Josh Poimboeuf   authored and   Greg Kroah-Hartman   commited 2019-08-06 18:29:42 +02:00
410b20dd6f
objtool: Don't use ignore flag for fake jumps
[ Upstream commit e6da9567959e164f82bc81967e0d5b10dee870b4 ]

The ignore flag is set on fake jumps in order to keep
add_jump_destinations() from setting their jump_dest, since it already
got set when the fake jump was created.

But using the ignore flag is a bit of a hack.  It's normally used to
skip validation of an instruction, which doesn't really make sense for
fake jumps.

Also, after the next patch, using the ignore flag for fake jumps can
trigger a false "why am I validating an ignored function?" warning.

Instead just add an explicit check in add_jump_destinations() to skip
fake jumps.

Signed-off-by: Josh Poimboeuf <jpoimboe@redhat.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Link: http://lkml.kernel.org/r/71abc072ff48b2feccc197723a9c52859476c068.1557766718.git.jpoimboe@redhat.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>

Josh Poimboeuf   authored and   Greg Kroah-Hartman   commited 2019-06-22 08:17:13 +02:00
4ba76bf213
objtool: Allow AR to be overridden with HOSTAR
commit 8ea58f1e8b11cca3087b294779bf5959bf89cc10 upstream.

Currently, this Makefile hardcodes GNU ar, meaning that if it is not
available, there is no way to supply a different one and the build will
fail.

  $ make AR=llvm-ar CC=clang LD=ld.lld HOSTAR=llvm-ar HOSTCC=clang \
         HOSTLD=ld.lld HOSTLDFLAGS=-fuse-ld=lld defconfig modules_prepare
  ...
    AR       /out/tools/objtool/libsubcmd.a
  /bin/sh: 1: ar: not found
  ...

Follow the logic of HOST{CC,LD} and allow the user to specify a
different ar tool via HOSTAR (which is used elsewhere in other
tools/ Makefiles).

Signed-off-by: Nathan Chancellor <natechancellor@gmail.com>
Signed-off-by: Josh Poimboeuf <jpoimboe@redhat.com>
Reviewed-by: Nick Desaulniers <ndesaulniers@google.com>
Reviewed-by: Mukesh Ojha <mojha@codeaurora.org>
Cc: <stable@vger.kernel.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Link: http://lkml.kernel.org/r/80822a9353926c38fd7a152991c6292491a9d0e8.1558028966.git.jpoimboe@redhat.com
Link: https://github.com/ClangBuiltLinux/linux/issues/481
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

Nathan Chancellor   authored and   Greg Kroah-Hartman   commited 2019-05-25 18:26:50 +02:00
2bfc2e3623
objtool: Fix function fallthrough detection
commit e6f393bc939d566ce3def71232d8013de9aaadde upstream.

When a function falls through to the next function due to a compiler
bug, objtool prints some obscure warnings.  For example:

  drivers/regulator/core.o: warning: objtool: regulator_count_voltages()+0x95: return with modified stack frame
  drivers/regulator/core.o: warning: objtool: regulator_count_voltages()+0x0: stack state mismatch: cfa1=7+32 cfa2=7+8

Instead it should be printing:

  drivers/regulator/core.o: warning: objtool: regulator_supply_is_couple() falls through to next function regulator_count_voltages()

This used to work, but was broken by the following commit:

  13810435b9a7 ("objtool: Support GCC 8's cold subfunctions")

The padding nops at the end of a function aren't actually part of the
function, as defined by the symbol table.  So the 'func' variable in
validate_branch() is getting cleared to NULL when a padding nop is
encountered, breaking the fallthrough detection.

If the current instruction doesn't have a function associated with it,
just consider it to be part of the previously detected function by not
overwriting the previous value of 'func'.

Reported-by: kbuild test robot <lkp@intel.com>
Signed-off-by: Josh Poimboeuf <jpoimboe@redhat.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: <stable@vger.kernel.org>
Fixes: 13810435b9a7 ("objtool: Support GCC 8's cold subfunctions")
Link: http://lkml.kernel.org/r/546d143820cd08a46624ae8440d093dd6c902cae.1557766718.git.jpoimboe@redhat.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

Josh Poimboeuf   authored and   Greg Kroah-Hartman   commited 2019-05-21 18:48:56 +02:00
15e6da9ae5
objtool: Move objtool_file struct off the stack
commit 0c671812f152b628bd87c0af49da032cc2a2c319 upstream.

Objtool uses over 512k of stack, thanks to the hash table embedded in
the objtool_file struct.  This causes an unnecessarily large stack
allocation and breaks users with low stack limits.

Move the struct off the stack.

Fixes: 042ba73fe7 ("objtool: Add several performance improvements")
Reported-by: Vassili Karpov <moosotc@gmail.com>
Signed-off-by: Josh Poimboeuf <jpoimboe@redhat.com>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: stable@vger.kernel.org
Link: https://lkml.kernel.org/r/df92dcbc4b84b02ffa252f46876df125fb56e2d7.1552954176.git.jpoimboe@redhat.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

Josh Poimboeuf   authored and   Greg Kroah-Hartman   commited 2019-03-27 14:13:03 +09:00
c818b2face
objtool: Fix segfault in .cold detection with -ffunction-sections
[ Upstream commit 22566c1603030f0a036ad564634b064ad1a55db2 ]

Because find_symbol_by_name() traverses the same lists as
read_symbols(), changing sym->name in place without copying it affects
the result of find_symbol_by_name().  In the case where a ".cold"
function precedes its parent in sec->symbol_list, it can result in a
function being considered a parent of itself. This leads to function
length being set to 0 and other consequent side-effects including a
segfault in add_switch_table().  The effects of this bug are only
visible when building with -ffunction-sections in KCFLAGS.

Fix by copying the search string instead of modifying it in place.

Signed-off-by: Artem Savkov <asavkov@redhat.com>
Signed-off-by: Josh Poimboeuf <jpoimboe@redhat.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Fixes: 13810435b9a7 ("objtool: Support GCC 8's cold subfunctions")
Link: http://lkml.kernel.org/r/910abd6b5a4945130fd44f787c24e07b9e07c8da.1542736240.git.jpoimboe@redhat.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>

Artem Savkov   authored and   Greg Kroah-Hartman   commited 2018-12-17 09:38:32 +01:00
779f4eecbc
objtool: Fix double-free in .cold detection error path
[ Upstream commit 0b9301fb632f7111a3293a30cc5b20f1b82ed08d ]

If read_symbols() fails during second list traversal (the one dealing
with ".cold" subfunctions) it frees the symbol, but never deletes it
from the list/hash_table resulting in symbol being freed again in
elf_close(). Fix it by just returning an error, leaving cleanup to
elf_close().

Signed-off-by: Artem Savkov <asavkov@redhat.com>
Signed-off-by: Josh Poimboeuf <jpoimboe@redhat.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Fixes: 13810435b9a7 ("objtool: Support GCC 8's cold subfunctions")
Link: http://lkml.kernel.org/r/beac5a9b7da9e8be90223459dcbe07766ae437dd.1542736240.git.jpoimboe@redhat.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>

Artem Savkov   authored and   Greg Kroah-Hartman   commited 2018-12-17 09:38:32 +01:00
63bc6364fb
objtool: Support GCC 8 '-fnoreorder-functions'
[ Upstream commit 08b393d01c88aff27347ed2b1b354eb4db2f1532 ]

Since the following commit:

  cd77849a69cf ("objtool: Fix GCC 8 cold subfunction detection for aliased functions")

... if the kernel is built with EXTRA_CFLAGS='-fno-reorder-functions',
objtool can get stuck in an infinite loop.

That flag causes the new GCC 8 cold subfunctions to be placed in .text
instead of .text.unlikely.  But it also has an unfortunate quirk: in the
symbol table, the subfunction (e.g., nmi_panic.cold.7) is nested inside
the parent (nmi_panic).

That function overlap confuses objtool, and causes it to get into an
infinite loop in next_insn_same_func().  Here's Allan's description of
the loop:

  "Objtool iterates through the instructions in nmi_panic using
  next_insn_same_func. Once it reaches the end of nmi_panic at 0x534 it
  jumps to 0x528 as that's the start of nmi_panic.cold.7. However, since
  the instructions starting at 0x528 are still associated with nmi_panic
  objtool will get stuck in a loop, continually jumping back to 0x528
  after reaching 0x534."

Fix it by shortening the length of the parent function so that the
functions no longer overlap.

Reported-and-analyzed-by: Allan Xavier <allan.x.xavier@oracle.com>
Signed-off-by: Josh Poimboeuf <jpoimboe@redhat.com>
Cc: Allan Xavier <allan.x.xavier@oracle.com>
Cc: Andy Lutomirski <luto@kernel.org>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Brian Gerst <brgerst@gmail.com>
Cc: Denys Vlasenko <dvlasenk@redhat.com>
Cc: H. Peter Anvin <hpa@zytor.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Link: http://lkml.kernel.org/r/9e704c52bee651129b036be14feda317ae5606ae.1530136978.git.jpoimboe@redhat.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Signed-off-by: Sasha Levin <alexander.levin@microsoft.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

Josh Poimboeuf   authored and   Greg Kroah-Hartman   commited 2018-08-24 13:12:35 +02:00
ce94ead620
Kbuild: fix # escaping in .cmd files for future Make
commit 9564a8cf422d7b58f6e857e3546d346fa970191e upstream.

I tried building using a freshly built Make (4.2.1-69-g8a731d1), but
already the objtool build broke with

orc_dump.c: In function ‘orc_dump’:
orc_dump.c:106:2: error: ‘elf_getshnum’ is deprecated [-Werror=deprecated-declarations]
  if (elf_getshdrnum(elf, &nr_sections)) {

Turns out that with that new Make, the backslash was not removed, so cpp
didn't see a #include directive, grep found nothing, and
-DLIBELF_USE_DEPRECATED was wrongly put in CFLAGS.

Now, that new Make behaviour is documented in their NEWS file:

  * WARNING: Backward-incompatibility!
    Number signs (#) appearing inside a macro reference or function invocation
    no longer introduce comments and should not be escaped with backslashes:
    thus a call such as:
      foo := $(shell echo '#')
    is legal.  Previously the number sign needed to be escaped, for example:
      foo := $(shell echo '\#')
    Now this latter will resolve to "\#".  If you want to write makefiles
    portable to both versions, assign the number sign to a variable:
      C := \#
      foo := $(shell echo '$C')
    This was claimed to be fixed in 3.81, but wasn't, for some reason.
    To detect this change search for 'nocomment' in the .FEATURES variable.

This also fixes up the two make-cmd instances to replace # with $(pound)
rather than with \#. There might very well be other places that need
similar fixup in preparation for whatever future Make release contains
the above change, but at least this builds an x86_64 defconfig with the
new make.

Link: https://bugzilla.kernel.org/show_bug.cgi?id=197847
Cc: Randy Dunlap <rdunlap@infradead.org>
Signed-off-by: Rasmus Villemoes <linux@rasmusvillemoes.dk>
Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

Rasmus Villemoes   authored and   Greg Kroah-Hartman   commited 2018-07-11 16:26:45 +02:00
b5d7d7d919
objtool: update .gitignore file
With the recent sync with objtool from 4.14.y, the objtool .gitignore
file was forgotten.  Fix that up now to properly handle the change in
where the autogenerated files live.

Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

Greg Kroah-Hartman   commited 2018-06-26 08:08:05 +08:00
ccd19d3a38
objtool: header file sync-up
When building tools/objtool/ it rightly complains about a number of
files being out of sync.  Fix this up by syncing them properly with the
relevant in-kernel versions.

Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

Greg Kroah-Hartman   commited 2018-06-05 10:28:58 +02:00
269e590632
objtool: Fix "noreturn" detection for recursive sibling calls
commit 0afd0d9e0e7879d666c1df2fa1bea4d8716909fe upstream.

Objtool has some crude logic for detecting static "noreturn" functions
(aka "dead ends").  This is necessary for being able to correctly follow
GCC code flow when such functions are called.

It's remotely possible for two functions to call each other via sibling
calls.  If they don't have RET instructions, objtool's noreturn
detection logic goes into a recursive loop:

  drivers/char/ipmi/ipmi_ssif.o: warning: objtool: return_hosed_msg()+0x0: infinite recursion (objtool bug!)
  drivers/char/ipmi/ipmi_ssif.o: warning: objtool: deliver_recv_msg()+0x0: infinite recursion (objtool bug!)

Instead of reporting an error in this case, consider the functions to be
non-dead-ends.

Reported-and-tested-by: Randy Dunlap <rdunlap@infradead.org>
Signed-off-by: Josh Poimboeuf <jpoimboe@redhat.com>
Acked-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Cc: Arnd Bergmann <arnd@arndb.de>
Cc: David Laight <David.Laight@ACULAB.COM>
Cc: Greg KH <gregkh@linuxfoundation.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: damian <damian.tometzki@icloud.com>
Link: http://lkml.kernel.org/r/7cc156408c5781a1f62085d352ced1fe39fe2f91.1525923412.git.jpoimboe@redhat.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

Josh Poimboeuf   authored and   Greg Kroah-Hartman   commited 2018-06-05 10:28:57 +02:00
9aebb3d3a0
objtool: Detect RIP-relative switch table references, part 2
commit 7dec80ccbe310fb7e225bf21c48c672bb780ce7b upstream.

With the following commit:

  fd35c88b7417 ("objtool: Support GCC 8 switch tables")

I added a "can't find switch jump table" warning, to stop covering up
silent failures if add_switch_table() can't find anything.

That warning found yet another bug in the objtool switch table detection
logic.  For cases 1 and 2 (as described in the comments of
find_switch_table()), the find_symbol_containing() check doesn't adjust
the offset for RIP-relative switch jumps.

Incidentally, this bug was already fixed for case 3 with:

  6f5ec2993b1f ("objtool: Detect RIP-relative switch table references")

However, that commit missed the fix for cases 1 and 2.

The different cases are now starting to look more and more alike.  So
fix the bug by consolidating them into a single case, by checking the
original dynamic jump instruction in the case 3 loop.

This also simplifies the code and makes it more robust against future
switch table detection issues -- of which I'm sure there will be many...

Switch table detection has been the most fragile area of objtool, by
far.  I long for the day when we'll have a GCC plugin for annotating
switch tables.  Linus asked me to delay such a plugin due to the
flakiness of the plugin infrastructure in older versions of GCC, so this
rickety code is what we're stuck with for now.  At least the code is now
a little simpler than it was.

Reported-by: kbuild test robot <lkp@intel.com>
Signed-off-by: Josh Poimboeuf <jpoimboe@redhat.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Link: http://lkml.kernel.org/r/f400541613d45689086329432f3095119ffbc328.1526674218.git.jpoimboe@redhat.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

Josh Poimboeuf   authored and   Greg Kroah-Hartman   commited 2018-06-05 10:28:57 +02:00
603a2cdf10
objtool: Detect RIP-relative switch table references
commit 6f5ec2993b1f39aed12fa6fd56e8dc2272ee8a33 upstream.

Typically a switch table can be found by detecting a .rodata access
followed an indirect jump:

    1969:	4a 8b 0c e5 00 00 00 	mov    0x0(,%r12,8),%rcx
    1970:	00
			196d: R_X86_64_32S	.rodata+0x438
    1971:	e9 00 00 00 00       	jmpq   1976 <dispc_runtime_suspend+0xb6a>
			1972: R_X86_64_PC32	__x86_indirect_thunk_rcx-0x4

Randy Dunlap reported a case (seen with GCC 4.8) where the .rodata
access uses RIP-relative addressing:

    19bd:	48 8b 3d 00 00 00 00 	mov    0x0(%rip),%rdi        # 19c4 <dispc_runtime_suspend+0xbb8>
			19c0: R_X86_64_PC32	.rodata+0x45c
    19c4:	e9 00 00 00 00       	jmpq   19c9 <dispc_runtime_suspend+0xbbd>
			19c5: R_X86_64_PC32	__x86_indirect_thunk_rdi-0x4

In this case the relocation addend needs to be adjusted accordingly in
order to find the location of the switch table.

The fix is for case 3 (as described in the comments), but also make the
existing case 1 & 2 checks more precise by only adjusting the addend for
R_X86_64_PC32 relocations.

This fixes the following warnings:

  drivers/video/fbdev/omap2/omapfb/dss/dispc.o: warning: objtool: dispc_runtime_suspend()+0xbb8: sibling call from callable instruction with modified stack frame
  drivers/video/fbdev/omap2/omapfb/dss/dispc.o: warning: objtool: dispc_runtime_resume()+0xcc5: sibling call from callable instruction with modified stack frame

Reported-by: Randy Dunlap <rdunlap@infradead.org>
Signed-off-by: Josh Poimboeuf <jpoimboe@redhat.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Link: http://lkml.kernel.org/r/b6098294fd67afb69af8c47c9883d7a68bf0f8ea.1526305958.git.jpoimboe@redhat.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

Josh Poimboeuf   authored and   Greg Kroah-Hartman   commited 2018-06-05 10:28:57 +02:00
48dc537b22
objtool: Support GCC 8 switch tables
commit fd35c88b74170d9335530d9abf271d5d73eb5401 upstream.

With GCC 8, some issues were found with the objtool switch table
detection.

1) In the .rodata section, immediately after the switch table, there can
   be another object which contains a pointer to the function which had
   the switch statement.  In this case objtool wrongly considers the
   function pointer to be part of the switch table.  Fix it by:

   a) making sure there are no pointers to the beginning of the
      function; and

   b) making sure there are no gaps in the switch table.

   Only the former was needed, the latter adds additional protection for
   future optimizations.

2) In find_switch_table(), case 1 and case 2 are missing the check to
   ensure that the .rodata switch table data is anonymous, i.e. that it
   isn't already associated with an ELF symbol.  Fix it by adding the
   same find_symbol_containing() check which is used for case 3.

This fixes the following warnings with GCC 8:

  drivers/block/virtio_blk.o: warning: objtool: virtio_queue_rq()+0x0: stack state mismatch: cfa1=7+8 cfa2=7+72
  net/ipv6/icmp.o: warning: objtool: icmpv6_rcv()+0x0: stack state mismatch: cfa1=7+8 cfa2=7+64
  drivers/usb/core/quirks.o: warning: objtool: quirks_param_set()+0x0: stack state mismatch: cfa1=7+8 cfa2=7+48
  drivers/mtd/nand/raw/nand_hynix.o: warning: objtool: hynix_nand_decode_id()+0x0: stack state mismatch: cfa1=7+8 cfa2=7+24
  drivers/mtd/nand/raw/nand_samsung.o: warning: objtool: samsung_nand_decode_id()+0x0: stack state mismatch: cfa1=7+8 cfa2=7+32
  drivers/gpu/drm/nouveau/nvkm/subdev/top/gk104.o: warning: objtool: gk104_top_oneinit()+0x0: stack state mismatch: cfa1=7+8 cfa2=7+64

Reported-by: Arnd Bergmann <arnd@arndb.de>
Reported-by: kbuild test robot <lkp@intel.com>
Signed-off-by: Josh Poimboeuf <jpoimboe@redhat.com>
Acked-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Cc: David Laight <David.Laight@ACULAB.COM>
Cc: Greg KH <gregkh@linuxfoundation.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Randy Dunlap <rdunlap@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: damian <damian.tometzki@icloud.com>
Link: http://lkml.kernel.org/r/20180510224849.xwi34d6tzheb5wgw@treble
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

Josh Poimboeuf   authored and   Greg Kroah-Hartman   commited 2018-06-05 10:28:57 +02:00
7cd91856f5
objtool: Support GCC 8's cold subfunctions
commit 13810435b9a7014fb92eb715f77da488f3b65b99 upstream.

GCC 8 moves a lot of unlikely code out of line to "cold" subfunctions in
.text.unlikely.  Properly detect the new subfunctions and treat them as
extensions of the original functions.

This fixes a bunch of warnings like:

  kernel/cgroup/cgroup.o: warning: objtool: parse_cgroup_root_flags()+0x33: sibling call from callable instruction with modified stack frame
  kernel/cgroup/cgroup.o: warning: objtool: cgroup_addrm_files()+0x290: sibling call from callable instruction with modified stack frame
  kernel/cgroup/cgroup.o: warning: objtool: cgroup_apply_control_enable()+0x25b: sibling call from callable instruction with modified stack frame
  kernel/cgroup/cgroup.o: warning: objtool: rebind_subsystems()+0x325: sibling call from callable instruction with modified stack frame

Reported-and-tested-by: damian <damian.tometzki@icloud.com>
Reported-by: Arnd Bergmann <arnd@arndb.de>
Signed-off-by: Josh Poimboeuf <jpoimboe@redhat.com>
Acked-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Cc: David Laight <David.Laight@ACULAB.COM>
Cc: Greg KH <gregkh@linuxfoundation.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Randy Dunlap <rdunlap@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Link: http://lkml.kernel.org/r/0965e7fcfc5f31a276f0c7f298ff770c19b68706.1525923412.git.jpoimboe@redhat.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

Josh Poimboeuf   authored and   Greg Kroah-Hartman   commited 2018-06-05 10:28:57 +02:00
1f7f88aa4d
objtool: sync up with the 4.14.47 version of objtool
There are pros and cons of dealing with tools in the kernel directory.
The pros are the fact that development happens fast, and new features
can be added to the kernel and the tools at the same times.  The cons
are when dealing with backported kernel patches, it can be necessary to
backport parts of the tool changes as well.

For 4.9.y so far, we have backported individual patches.  That quickly
breaks down when there are minor differences between how backports were
handled, so grabbing 40+ patch long series can be difficult, not
impossible, but really frustrating to attempt.

To help mitigate this mess, here's a single big patch to sync up the
objtool logic to the 4.14.47 version of the tool.  From this point
forward (after some other minor header file patches are applied), the
tool should be in sync and much easier to maintain over time.

This has survivied my limited testing, and as the codebase is identical
to 4.14.47, I'm pretty comfortable dropping this big change in here in
4.9.y.  Hopefully all goes well...

Cc: Josh Poimboeuf <jpoimboe@redhat.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

Greg Kroah-Hartman   commited 2018-06-05 10:28:57 +02:00
b790b4f22a
objtool: Move checking code to check.c
commit dcc914f44f065ef73685b37e59877a5bb3cb7358 upstream.

In preparation for the new 'objtool undwarf generate' command, which
will rely on 'objtool check', move the checking code from
builtin-check.c to check.c where it can be used by other commands.

Signed-off-by: Josh Poimboeuf <jpoimboe@redhat.com>
Reviewed-by: Jiri Slaby <jslaby@suse.cz>
Cc: Andy Lutomirski <luto@kernel.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: live-patching@vger.kernel.org
Link: http://lkml.kernel.org/r/294c5c695fd73c1a5000bbe5960a7c9bec4ee6b4.1498659915.git.jpoimboe@redhat.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
[backported by hand to 4.9, this was a pain... - gregkh]
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

Josh Poimboeuf   authored and   Greg Kroah-Hartman   commited 2018-06-05 10:28:55 +02:00
24ac7a44f7
objtool: Improve detection of BUG() and other dead ends
commit d1091c7fa3d52ebce4dd3f15d04155b3469b2f90 upstream.

The BUG() macro's use of __builtin_unreachable() via the unreachable()
macro tells gcc that the instruction is a dead end, and that it's safe
to assume the current code path will not execute past the previous
instruction.

On x86, the BUG() macro is implemented with the 'ud2' instruction.  When
objtool's branch analysis sees that instruction, it knows the current
code path has come to a dead end.

Peter Zijlstra has been working on a patch to change the WARN macros to
use 'ud2'.  That patch will break objtool's assumption that 'ud2' is
always a dead end.

Generally it's best for objtool to avoid making those kinds of
assumptions anyway.  The more ignorant it is of kernel code internals,
the better.

So create a more generic way for objtool to detect dead ends by adding
an annotation to the unreachable() macro.  The annotation stores a
pointer to the end of the unreachable code path in an '__unreachable'
section.  Objtool can read that section to find the dead ends.

Tested-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Signed-off-by: Josh Poimboeuf <jpoimboe@redhat.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Link: http://lkml.kernel.org/r/41a6d33971462ebd944a1c60ad4bf5be86c17b77.1487712920.git.jpoimboe@redhat.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

Josh Poimboeuf   authored and   Greg Kroah-Hartman   commited 2018-06-05 10:28:55 +02:00
add0ff1791
objtool: Improve error message for bad file argument
commit 385d11b152c4eb638eeb769edcb3249533bb9a00 upstream.

If a nonexistent file is supplied to objtool, it complains with a
non-helpful error:

  open: No such file or directory

Improve it to:

  objtool: Can't open 'foo': No such file or directory

Reported-by: Markus <M4rkusXXL@web.de>
Signed-off-by: Josh Poimboeuf <jpoimboe@redhat.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Link: http://lkml.kernel.org/r/406a3d00a21225eee2819844048e17f68523ccf6.1516025651.git.jpoimboe@redhat.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

Josh Poimboeuf   authored and   Greg Kroah-Hartman   commited 2018-01-23 19:57:05 +01:00
13ccac5de8
objtool: Fix retpoline support for pre-ORC objtool
Objtool 1.0 (pre-ORC) produces the following warning when it encounters
a retpoline:

  arch/x86/crypto/camellia-aesni-avx2-asm_64.o: warning: objtool: .altinstr_replacement+0xf: return instruction outside of a callable function

That warning is meant to catch GCC bugs and missing ENTRY/ENDPROC
annotations, neither of which are applicable to alternatives.  Silence
the warning for alternative instructions, just like objtool 2.0 already
does.

Reported-by: David Woodhouse <dwmw2@infradead.org>
Signed-off-by: Josh Poimboeuf <jpoimboe@redhat.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

Josh Poimboeuf   authored and   Greg Kroah-Hartman   commited 2018-01-17 09:39:00 +01:00
92e8f20494
objtool: Allow alternatives to be ignored
commit 258c76059cece01bebae098e81bacb1af2edad17 upstream.

Getting objtool to understand retpolines is going to be a bit of a
challenge.  For now, take advantage of the fact that retpolines are
patched in with alternatives.  Just read the original (sane)
non-alternative instruction, and ignore the patched-in retpoline.

This allows objtool to understand the control flow *around* the
retpoline, even if it can't yet follow what's inside.  This means the
ORC unwinder will fail to unwind from inside a retpoline, but will work
fine otherwise.

Signed-off-by: Josh Poimboeuf <jpoimboe@redhat.com>
Signed-off-by: David Woodhouse <dwmw@amazon.co.uk>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Cc: gnomes@lxorguk.ukuu.org.uk
Cc: Rik van Riel <riel@redhat.com>
Cc: Andi Kleen <ak@linux.intel.com>
Cc: thomas.lendacky@amd.com
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Jiri Kosina <jikos@kernel.org>
Cc: Andy Lutomirski <luto@amacapital.net>
Cc: Dave Hansen <dave.hansen@intel.com>
Cc: Kees Cook <keescook@google.com>
Cc: Tim Chen <tim.c.chen@linux.intel.com>
Cc: Greg Kroah-Hartman <gregkh@linux-foundation.org>
Cc: Paul Turner <pjt@google.com>
Link: https://lkml.kernel.org/r/1515707194-20531-3-git-send-email-dwmw@amazon.co.uk
[dwmw2: Applies to tools/objtool/builtin-check.c not check.[ch]]
Signed-off-by: David Woodhouse <dwmw@amazon.co.uk>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

Josh Poimboeuf   authored and   Greg Kroah-Hartman   commited 2018-01-17 09:38:58 +01:00
4d8bd3e2f6
objtool: Detect jumps to retpoline thunks
commit 39b735332cb8b33a27c28592d969e4016c86c3ea upstream.

A direct jump to a retpoline thunk is really an indirect jump in
disguise.  Change the objtool instruction type accordingly.

Objtool needs to know where indirect branches are so it can detect
switch statement jump tables.

This fixes a bunch of warnings with CONFIG_RETPOLINE like:

  arch/x86/events/intel/uncore_nhmex.o: warning: objtool: nhmex_rbox_msr_enable_event()+0x44: sibling call from callable instruction with modified stack frame
  kernel/signal.o: warning: objtool: copy_siginfo_to_user()+0x91: sibling call from callable instruction with modified stack frame
  ...

Signed-off-by: Josh Poimboeuf <jpoimboe@redhat.com>
Signed-off-by: David Woodhouse <dwmw@amazon.co.uk>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Cc: gnomes@lxorguk.ukuu.org.uk
Cc: Rik van Riel <riel@redhat.com>
Cc: Andi Kleen <ak@linux.intel.com>
Cc: thomas.lendacky@amd.com
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Jiri Kosina <jikos@kernel.org>
Cc: Andy Lutomirski <luto@amacapital.net>
Cc: Dave Hansen <dave.hansen@intel.com>
Cc: Kees Cook <keescook@google.com>
Cc: Tim Chen <tim.c.chen@linux.intel.com>
Cc: Greg Kroah-Hartman <gregkh@linux-foundation.org>
Cc: Paul Turner <pjt@google.com>
Link: https://lkml.kernel.org/r/1515707194-20531-2-git-send-email-dwmw@amazon.co.uk
[dwmw2: Applies to tools/objtool/builtin-check.c not check.c]
Signed-off-by: David Woodhouse <dwmw@amazon.co.uk>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

Josh Poimboeuf   authored and   Greg Kroah-Hartman   commited 2018-01-17 09:38:58 +01:00
3adb52ab29
objtool, modules: Discard objtool annotation sections for modules
commit e390f9a9689a42f477a6073e2e7df530a4c1b740 upstream.

The '__unreachable' and '__func_stack_frame_non_standard' sections are
only used at compile time.  They're discarded for vmlinux but they
should also be discarded for modules.

Since this is a recurring pattern, prefix the section names with
".discard.".  It's a nice convention and vmlinux.lds.h already discards
such sections.

Also remove the 'a' (allocatable) flag from the __unreachable section
since it doesn't make sense for a discarded section.

Suggested-by: Linus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: Josh Poimboeuf <jpoimboe@redhat.com>
Cc: Jessica Yu <jeyu@redhat.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Fixes: d1091c7fa3d5 ("objtool: Improve detection of BUG() and other dead ends")
Link: http://lkml.kernel.org/r/20170301180444.lhd53c5tibc4ns77@treble
Signed-off-by: Ingo Molnar <mingo@kernel.org>
[dwmw2: Remove the unreachable part in backporting since it's not here yet]
Signed-off-by: David Woodhouse <dwmw@amazon.co.ku>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

Josh Poimboeuf   authored and   Greg Kroah-Hartman   commited 2018-01-17 09:38:58 +01:00
35aee626fa
sync objtool's copy of x86-opcode-map.txt
When building objtool, we get the warning:
	warning: objtool: x86 instruction decoder differs from kernel

That's due to commit 2816c0455c which was
commit 12a78d43de767eaf8fb272facb7a7b6f2dc6a9df upstream that modified
arch/x86/lib/x86-opcode-map.txt without also updating the objtool copy.
The objtool copy was updated in a much larger patch upstream, but we
don't need all of that here, so just update the single file.

If this gets too annoying, I'll just end up doing what we did for 4.14
and backport the whole series to keep this from happening again, but as
this seems to be rare in the 4.9-stable series, this single patch should
be fine.

Cc: Masami Hiramatsu <mhiramat@kernel.org>
Cc: H. Peter Anvin <hpa@zytor.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Ingo Molnar <mingo@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

Greg Kroah-Hartman   commited 2018-01-02 20:35:06 +01:00
3d16a1315a
objtool: Fix another GCC jump table detection issue
commit 5c51f4ae84df0f9df33ac08aa5be50061a8b4242 upstream.

Arnd Bergmann reported a (false positive) objtool warning:

  drivers/infiniband/sw/rxe/rxe_resp.o: warning: objtool: rxe_responder()+0xfe: sibling call from callable instruction with changed frame pointer

The issue is in find_switch_table().  It tries to find a switch
statement's jump table by walking backwards from an indirect jump
instruction, looking for a relocation to the .rodata section.  In this
case it stopped walking prematurely: the first .rodata relocation it
encountered was for a variable (resp_state_name) instead of a jump
table, so it just assumed there wasn't a jump table.

The fix is to ignore any .rodata relocation which refers to an ELF
object symbol.  This works because the jump tables are anonymous and
have no symbols associated with them.

Reported-by: Arnd Bergmann <arnd@arndb.de>
Tested-by: Arnd Bergmann <arnd@arndb.de>
Signed-off-by: Josh Poimboeuf <jpoimboe@redhat.com>
Cc: Denys Vlasenko <dvlasenk@redhat.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Fixes: 3732710ff6 ("objtool: Improve rare switch jump table pattern detection")
Link: http://lkml.kernel.org/r/20170302225723.3ndbsnl4hkqbne7a@treble
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

Josh Poimboeuf   authored and   Greg Kroah-Hartman   commited 2017-07-05 14:40:30 +02:00
3e51ccbadd
objtool: Fix IRET's opcode
[ Upstream commit b5b46c4740aed1538544f0fa849c5b76c7823469 ]

The IRET opcode is 0xcf according to the Intel manual and also to objdump of my
vmlinux:

    1ea8:       48 cf                   iretq

Fix the opcode in arch_decode_instruction().

The previous value (0xc5) seems to correspond to LDS.

Signed-off-by: Jiri Slaby <jslaby@suse.cz>
Acked-by: Josh Poimboeuf <jpoimboe@redhat.com>
Cc: Andy Lutomirski <luto@kernel.org>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Brian Gerst <brgerst@gmail.com>
Cc: Denys Vlasenko <dvlasenk@redhat.com>
Cc: H. Peter Anvin <hpa@zytor.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Link: http://lkml.kernel.org/r/20170118132921.19319-1-jslaby@suse.cz
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Signed-off-by: Sasha Levin <alexander.levin@verizon.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

Jiri Slaby   authored and   Greg Kroah-Hartman   commited 2017-07-05 14:40:22 +02:00
c48a862c47
objtool: Fix bytes check of lea's rex_prefix
For the "lea %(rsp), %rbp" case, we check if there is a rex_prefix.
But we check 'bytes' which is insn_byte_t[4] in rex_prefix (insn_field
structure). Therefore, the check is always true.

Instead, check 'nbytes' which is the right one.

Signed-off-by: Jiri Slaby <jslaby@suse.cz>
Acked-by: Josh Poimboeuf <jpoimboe@redhat.com>
Cc: Andy Lutomirski <luto@kernel.org>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Brian Gerst <brgerst@gmail.com>
Cc: Denys Vlasenko <dvlasenk@redhat.com>
Cc: H. Peter Anvin <hpa@zytor.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Link: http://lkml.kernel.org/r/20161205105551.25917-1-jslaby@suse.cz
Signed-off-by: Ingo Molnar <mingo@kernel.org>

Jiri Slaby   authored and   Ingo Molnar   commited 2016-12-06 09:20:59 +01:00
69042bf200
objtool: Fix rare switch jump table pattern detection
The following commit:

  3732710ff6 ("objtool: Improve rare switch jump table pattern detection")

... improved objtool's ability to detect GCC switch statement jump
tables for GCC 6.  However the check to allow short jumps with the
scanned range of instructions wasn't quite right.  The pattern detection
should allow jumps to the indirect jump instruction itself.

This fixes the following warning:

  drivers/infiniband/sw/rxe/rxe_comp.o: warning: objtool: rxe_completer()+0x315: sibling call from callable instruction with changed frame pointer

Reported-by: Arnd Bergmann <arnd@arndb.de>
Signed-off-by: Josh Poimboeuf <jpoimboe@redhat.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Fixes: 3732710ff6 ("objtool: Improve rare switch jump table pattern detection")
Link: http://lkml.kernel.org/r/20161026153408.2rifnw7bvoc5sex7@treble
Signed-off-by: Ingo Molnar <mingo@kernel.org>

Josh Poimboeuf   authored and   Ingo Molnar   commited 2016-10-27 08:20:27 +02:00
56fb2d6eb6
objtool: Skip all "unreachable instruction" warnings for gcov kernels
Recently objtool has started reporting a few "unreachable instruction"
warnings when CONFIG_GCOV is enabled for newer versions of GCC.  Usually
this warning means there's some new control flow that objtool doesn't
understand.  But in this case, objtool is correct and the instructions
really are inaccessible.  It's an annoying quirk of gcov, but it's
harmless, so it's ok to just silence the warnings.

With older versions of GCC, it was relatively easy to detect
gcov-specific instructions and to skip any unreachable warnings produced
by them.  But GCC 6 has gotten craftier.

Instead of continuing to play whack-a-mole with gcov, just use a bigger,
more permanent hammer and disable unreachable warnings for the whole
file when gcov is enabled.  This is fine to do because a) unreachable
warnings are usually of questionable value; and b) gcov isn't used for
production kernels and we can relax the checks a bit there.

Reported-by: kbuild test robot <fengguang.wu@intel.com>
Signed-off-by: Josh Poimboeuf <jpoimboe@redhat.com>
Cc: Andy Lutomirski <luto@kernel.org>
Cc: Arnd Bergmann <arnd@arndb.de>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Brian Gerst <brgerst@gmail.com>
Cc: Denys Vlasenko <dvlasenk@redhat.com>
Cc: H. Peter Anvin <hpa@zytor.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Link: http://lkml.kernel.org/r/38d5c87d61d9cd46486dd2c86f46603dff0df86f.1476393584.git.jpoimboe@redhat.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>

Josh Poimboeuf   authored and   Ingo Molnar   commited 2016-10-16 09:12:36 +02:00
9cfffb1168
objtool: Improve rare switch jump table pattern detection
GCC 6 added a new switch statement jump table optimization which makes
objtool's life harder.  It looks like:

  mov [rodata addr],%reg1
  ... some instructions ...
  jmpq *(%reg1,%reg2,8)

The optimization is quite rare, but objtool still needs to be able to
identify the pattern so that it can follow all possible control flow
paths related to the switch statement.

In order to detect the pattern, objtool starts from the indirect jump
and scans backwards through the function until it finds the first
instruction in the pattern.  If it encounters an unconditional jump
along the way, it stops and considers the pattern to be not found.

As it turns out, unconditional jumps can happen, as long as they are
small forward jumps within the range being scanned.

This fixes the following warnings:

  drivers/infiniband/sw/rxe/rxe_comp.o: warning: objtool: rxe_completer()+0x2f4: sibling call from callable instruction with changed frame pointer
  drivers/infiniband/sw/rxe/rxe_resp.o: warning: objtool: rxe_responder()+0x10f: sibling call from callable instruction with changed frame pointer

Reported-by: Arnd Bergmann <arnd@arndb.de>
Signed-off-by: Josh Poimboeuf <jpoimboe@redhat.com>
Cc: Andy Lutomirski <luto@kernel.org>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Brian Gerst <brgerst@gmail.com>
Cc: Denys Vlasenko <dvlasenk@redhat.com>
Cc: H. Peter Anvin <hpa@zytor.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Link: http://lkml.kernel.org/r/8a9ed68ae1780e8d3963e4ee13f2f257fe3a3c33.1476393584.git.jpoimboe@redhat.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>

Josh Poimboeuf   authored and   Ingo Molnar   commited 2016-10-16 09:12:35 +02:00
3732710ff6
objtool: Support '-mtune=atom' stack frame setup instruction
Arnd reported that enabling CONFIG_MATOM results in a bunch of objtool
false positive frame pointer warnings:

  arch/x86/events/intel/ds.o: warning: objtool: intel_pmu_pebs_del()+0x43: call without frame pointer save/setup
  security/keys/keyring.o: warning: objtool: keyring_read()+0x59: call without frame pointer save/setup
  kernel/signal.o: warning: objtool: __dequeue_signal()+0xd8: call without frame pointer save/setup
  ...

objtool gets confused by the fact that the '-mtune=atom' GCC option
sometimes uses 'lea (%rsp),%rbp' instead of 'mov %rsp,%rbp'.  The
instructions are effectively the same, but objtool doesn't know about
the 'lea' variant.

Fix the false warnings by adding support for 'lea (%rsp),%rbp' in the
objtool decoder.

Reported-by: Arnd Bergmann <arnd@arndb.de>
Signed-off-by: Josh Poimboeuf <jpoimboe@redhat.com>
Cc: Andy Lutomirski <luto@kernel.org>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Brian Gerst <brgerst@gmail.com>
Cc: Denys Vlasenko <dvlasenk@redhat.com>
Cc: H. Peter Anvin <hpa@zytor.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: linux-kernel@vger.kernel.org
Signed-off-by: Ingo Molnar <mingo@kernel.org>

Josh Poimboeuf   authored and   Ingo Molnar   commited 2016-10-11 10:35:45 +02:00
2cc17fda94
objtool: Add do_task_dead() to global noreturn list
objtool reports the following new warning:

  kernel/exit.o: warning: objtool: do_exit() falls through to next function complete_and_exit()

The warning is caused by do_exit()'s new call to do_task_dead(), which
is a new "noreturn" function which objtool doesn't know about yet,
introduced by:

  9af6528ee9 ("sched/core: Optimize __schedule()")

( objtool has to know all the global noreturn functions so it can follow
  the control flow of any functions which call them.  Unfortunately they
  need to be hard-coded because there's no automated way to detect them. )

Reported-by: kbuild test robot <fengguang.wu@intel.com>
Signed-off-by: Josh Poimboeuf <jpoimboe@redhat.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: kbuild-all@01.org
Cc: tipbuild@zytor.com
Link: http://lkml.kernel.org/r/20160922212125.zbuewckqll4yur25@treble
Signed-off-by: Ingo Molnar <mingo@kernel.org>

Josh Poimboeuf   authored and   Ingo Molnar   commited 2016-09-23 07:28:05 +02:00
c1fad9ef7e
Merge branch 'core-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
Pull misc fixes from Thomas Gleixner:
 "This update contains:

   - a fix for stomp-machine so the nmi_watchdog wont trigger on the cpu
     waiting for the others to execute the callback

   - various fixes and updates to objtool including an resync of the
     instruction decoder to match the kernel's decoder"

* 'core-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  objtool: Un-capitalize "Warning" for out-of-sync instruction decoder
  objtool: Resync x86 instruction decoder with the kernel's
  objtool: Support new GCC 6 switch jump table pattern
  stop_machine: Touch_nmi_watchdog() after MULTI_STOP_PREPARE
  objtool: Add 'fixdep' to objtool/.gitignore

Linus Torvalds   commited 2016-07-30 11:54:53 -07:00
228ffba23e
objtool: Un-capitalize "Warning" for out-of-sync instruction decoder
Change "Warning" to "warning" to make it look more like a GCC warning.
Hopefully that will be enough to help the 0-day bot or other automated
tools catch this warning earlier before it ends up in Linus's tree.

Reported-by: Linus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: Josh Poimboeuf <jpoimboe@redhat.com>
Cc: Andy Lutomirski <luto@kernel.org>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Brian Gerst <brgerst@gmail.com>
Cc: Denys Vlasenko <dvlasenk@redhat.com>
Cc: H. Peter Anvin <hpa@zytor.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Link: http://lkml.kernel.org/r/b1669f391a5db91040427fd9f8e1e79db18f9709.1469751119.git.jpoimboe@redhat.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>

Josh Poimboeuf   authored and   Ingo Molnar   commited 2016-07-29 16:57:16 +02:00
2af04ea545
objtool: Resync x86 instruction decoder with the kernel's
This fixes the following warning:

  Warning: objtool: x86 instruction decoder differs from kernel

Unfortunately we have three identical copies of the x86 instruction
decoder in the kernel tree that have to be manually kept in sync.

It's on my TODO list to at least library-ize the ones in the tools
subdir so we'd only have two of them instead of three.  In the meantime,
here's another manual sync.

Reported-by: Linus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: Josh Poimboeuf <jpoimboe@redhat.com>
Cc: Andy Lutomirski <luto@kernel.org>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Brian Gerst <brgerst@gmail.com>
Cc: Denys Vlasenko <dvlasenk@redhat.com>
Cc: H. Peter Anvin <hpa@zytor.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Fixes: c61f4d5eba ("perf tools: Add AVX-512 support to the instruction decoder used by Intel PT")
Link: http://lkml.kernel.org/r/d7f74b4d91fed25b0be33cd5c86f5131fa1a7529.1469751119.git.jpoimboe@redhat.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>

Josh Poimboeuf   authored and   Ingo Molnar   commited 2016-07-29 16:57:16 +02:00
8d94c2f919
objtool: Support new GCC 6 switch jump table pattern
This fixes some false positive objtool warnings seen with gcc 6.1.1:

  kernel/trace/ring_buffer.o: warning: objtool: ring_buffer_read_page()+0x36c: sibling call from callable instruction with changed frame pointer
  arch/x86/kernel/reboot.o: warning: objtool: native_machine_emergency_restart()+0x139: sibling call from callable instruction with changed frame pointer
  lib/xz/xz_dec_stream.o: warning: objtool: xz_dec_run()+0xc2: sibling call from callable instruction with changed frame pointer

With GCC 6, a new code pattern is sometimes used to access a switch
statement jump table in .rodata, which objtool doesn't yet recognize:

  mov [rodata addr],%reg1
  ... some instructions ...
  jmpq *(%reg1,%reg2,8)

Add support for detecting that pattern.  The detection code is rather
crude, but it's still effective at weeding out false positives and
catching real warnings.  It can be refined later once objtool starts
reading DWARF CFI.

Reported-by: Linus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: Josh Poimboeuf <jpoimboe@redhat.com>
Cc: Andy Lutomirski <luto@kernel.org>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Brian Gerst <brgerst@gmail.com>
Cc: Denys Vlasenko <dvlasenk@redhat.com>
Cc: H. Peter Anvin <hpa@zytor.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Link: http://lkml.kernel.org/r/b8c9503b4ad8c8a827cc5400db4c1b40a3ea07bc.1469751119.git.jpoimboe@redhat.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>

Josh Poimboeuf   authored and   Ingo Molnar   commited 2016-07-29 16:56:21 +02:00
6d01f28bc0
libnvdimm for 4.8
1/ Replace pcommit with ADR / directed-flushing:
    The pcommit instruction, which has not shipped on any product, is
    deprecated. Instead, the requirement is that platforms implement either
    ADR, or provide one or more flush addresses per nvdimm. ADR
    (Asynchronous DRAM Refresh) flushes data in posted write buffers to the
    memory controller on a power-fail event. Flush addresses are defined in
    ACPI 6.x as an NVDIMM Firmware Interface Table (NFIT) sub-structure:
    "Flush Hint Address Structure". A flush hint is an mmio address that
    when written and fenced assures that all previous posted writes
    targeting a given dimm have been flushed to media.
 
 2/ On-demand ARS (address range scrub):
    Linux uses the results of the ACPI ARS commands to track bad blocks
    in pmem devices.  When latent errors are detected we re-scrub the media
    to refresh the bad block list, userspace can also request a re-scrub at
    any time.
 
 3/ Support for the Microsoft DSM (device specific method) command format.
 
 4/ Support for EDK2/OVMF virtual disk device memory ranges.
 
 5/ Various fixes and cleanups across the subsystem.
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Merge tag 'libnvdimm-for-4.8' of git://git.kernel.org/pub/scm/linux/kernel/git/nvdimm/nvdimm

Pull libnvdimm updates from Dan Williams:

 - Replace pcommit with ADR / directed-flushing.

   The pcommit instruction, which has not shipped on any product, is
   deprecated.  Instead, the requirement is that platforms implement
   either ADR, or provide one or more flush addresses per nvdimm.

   ADR (Asynchronous DRAM Refresh) flushes data in posted write buffers
   to the memory controller on a power-fail event.

   Flush addresses are defined in ACPI 6.x as an NVDIMM Firmware
   Interface Table (NFIT) sub-structure: "Flush Hint Address Structure".
   A flush hint is an mmio address that when written and fenced assures
   that all previous posted writes targeting a given dimm have been
   flushed to media.

 - On-demand ARS (address range scrub).

   Linux uses the results of the ACPI ARS commands to track bad blocks
   in pmem devices.  When latent errors are detected we re-scrub the
   media to refresh the bad block list, userspace can also request a
   re-scrub at any time.

 - Support for the Microsoft DSM (device specific method) command
   format.

 - Support for EDK2/OVMF virtual disk device memory ranges.

 - Various fixes and cleanups across the subsystem.

* tag 'libnvdimm-for-4.8' of git://git.kernel.org/pub/scm/linux/kernel/git/nvdimm/nvdimm: (41 commits)
  libnvdimm-btt: Delete an unnecessary check before the function call "__nd_device_register"
  nfit: do an ARS scrub on hitting a latent media error
  nfit: move to nfit/ sub-directory
  nfit, libnvdimm: allow an ARS scrub to be triggered on demand
  libnvdimm: register nvdimm_bus devices with an nd_bus driver
  pmem: clarify a debug print in pmem_clear_poison
  x86/insn: remove pcommit
  Revert "KVM: x86: add pcommit support"
  nfit, tools/testing/nvdimm/: unify shutdown paths
  libnvdimm: move ->module to struct nvdimm_bus_descriptor
  nfit: cleanup acpi_nfit_init calling convention
  nfit: fix _FIT evaluation memory leak + use after free
  tools/testing/nvdimm: add manufacturing_{date|location} dimm properties
  tools/testing/nvdimm: add virtual ramdisk range
  acpi, nfit: treat virtual ramdisk SPA as pmem region
  pmem: kill __pmem address space
  pmem: kill wmb_pmem()
  libnvdimm, pmem: use nvdimm_flush() for namespace I/O writes
  fs/dax: remove wmb_pmem()
  libnvdimm, pmem: flush posted-write queues on shutdown
  ...

Linus Torvalds   commited 2016-07-28 17:38:16 -07:00
f0c98ebc57
objtool: Add 'fixdep' to objtool/.gitignore
To fix:

   Untracked files:
     (use "git add <file>..." to include in what will be committed)

           tools/objtool/fixdep

Signed-off-by: Paul Gortmaker <paul.gortmaker@windriver.com>
Signed-off-by: Josh Poimboeuf <jpoimboe@redhat.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Link: http://lkml.kernel.org/r/a4571f6893caf737d05524cfa3829c2abc1fb240.1469452729.git.jpoimboe@redhat.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>

Paul Gortmaker   authored and   Ingo Molnar   commited 2016-07-27 11:07:11 +02:00
5cada17426
Merge branch 'perf-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
Pull perf fixes from Ingo Molnar:
 "This tree contains tooling fixes plus some additions:

   - fixes to the vdso2c build environment that Stephen Rothwell is
     using for the linux-next build (Arnaldo Carvalho de Melo)

   - AVX-512 instruction mappings (Adrian Hunter)

   - misc fixes"

* 'perf-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  Revert "perf tools: event.h needs asm/perf_regs.h"
  x86: Make the vdso2c compiler use the host architecture headers
  tools build: Fix objtool build with ARCH=x86_64
  objtool: Always use host headers
  objtool: Use tools/scripts/Makefile.arch to get ARCH and HOSTARCH
  tools build: Add HOSTARCH Makefile variable
  perf tests kmod-path: Fix build on ubuntu:16.04-x-armhf
  perf tools: Add AVX-512 instructions to the new instructions test
  perf tools: Add AVX-512 support to the instruction decoder used by Intel PT
  x86/insn: Add AVX-512 support to the instruction decoder
  x86/insn: perf tools: Fix vcvtph2ps instruction decoding

Linus Torvalds   commited 2016-07-26 10:26:29 -07:00
37e13a1ebe
Merge branch 'perf-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
Pull perf updates from Ingo Molnar:
 "With over 300 commits it's been a busy cycle - with most of the work
  concentrated on the tooling side (as it should).

  The main kernel side enhancements were:

   - Add per event callchain limit: Recently we introduced a sysctl to
     tune the max-stack for all events for which callchains were
     requested:

       $ sysctl kernel.perf_event_max_stack
       kernel.perf_event_max_stack = 127

     Now this patch introduces a way to configure this per event, i.e.
     this becomes possible:

       $ perf record -e sched:*/max-stack=2/ -e block:*/max-stack=10/ -a

     allowing finer tuning of how much buffer space callchains use.

     This uses an u16 from the reserved space at the end, leaving
     another u16 for future use.

     There has been interest in even finer tuning, namely to control the
     max stack for kernel and userspace callchains separately.  Further
     discussion is needed, we may for instance use the remaining u16 for
     that and when it is present, assume that the sample_max_stack
     introduced in this patch applies for the kernel, and the u16 left
     is used for limiting the userspace callchain (Arnaldo Carvalho de
     Melo)

   - Optimize AUX event (hardware assisted side-band event) delivery
     (Kan Liang)

   - Rework Intel family name macro usage (this is partially x86 arch
     work) (Dave Hansen)

   - Refine and fix Intel LBR support (David Carrillo-Cisneros)

   - Add support for Intel 'TopDown' events (Andi Kleen)

   - Intel uncore PMU driver fixes and enhancements (Kan Liang)

   - ... other misc changes.

  Here's an incomplete list of the tooling enhancements (but there's
  much more, see the shortlog and the git log for details):

   - Support cross unwinding, i.e.  collecting '--call-graph dwarf'
     perf.data files in one machine and then doing analysis in another
     machine of a different hardware architecture.  This enables, for
     instance, to do:

       $ perf record -a --call-graph dwarf

     on a x86-32 or aarch64 system and then do 'perf report' on it on a
     x86_64 workstation (He Kuang)

   - Allow reading from a backward ring buffer (one setup via
     sys_perf_event_open() with perf_event_attr.write_backward = 1)
     (Wang Nan)

   - Finish merging initial SDT (Statically Defined Traces) support, see
     cset comments for details about how it all works (Masami Hiramatsu)

   - Support attaching eBPF programs to tracepoints (Wang Nan)

   - Add demangling of symbols in programs written in the Rust language
     (David Tolnay)

   - Add support for tracepoints in the python binding, including an
     example, that sets up and parses sched:sched_switch events,
     tools/perf/python/tracepoint.py (Jiri Olsa)

   - Introduce --stdio-color to set up the color output mode selection
     in 'annotate' and 'report', allowing emit color escape sequences
     when redirecting the output of these tools (Arnaldo Carvalho de
     Melo)

   - Add 'callindent' option to 'perf script -F', to indent the Intel PT
     call stack, making this output more ftrace-like (Adrian Hunter,
     Andi Kleen)

   - Allow dumping the object files generated by llvm when processing
     eBPF scriptlet events (Wang Nan)

   - Add stackcollapse.py script to help generating flame graphs (Paolo
     Bonzini)

   - Add --ldlat option to 'perf mem' to specify load latency for loads
     event (e.g. cpu/mem-loads/ ) (Jiri Olsa)

   - Tooling support for Intel TopDown counters, recently added to the
     kernel (Andi Kleen)"

* 'perf-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (303 commits)
  perf tests: Add is_printable_array test
  perf tools: Make is_printable_array global
  perf script python: Fix string vs byte array resolving
  perf probe: Warn unmatched function filter correctly
  perf cpu_map: Add more helpers
  perf stat: Balance opening and reading events
  tools: Copy linux/{hash,poison}.h and check for drift
  perf tools: Remove include/linux/list.h from perf's MANIFEST
  tools: Copy the bitops files accessed from the kernel and check for drift
  Remove: kernel unistd*h files from perf's MANIFEST, not used
  perf tools: Remove tools/perf/util/include/linux/const.h
  perf tools: Remove tools/perf/util/include/asm/byteorder.h
  perf tools: Add missing linux/compiler.h include to perf-sys.h
  perf jit: Remove some no-op error handling
  perf jit: Add missing curly braces
  objtool: Initialize variable to silence old compiler
  objtool: Add -I$(srctree)/tools/arch/$(ARCH)/include/uapi
  perf record: Add --tail-synthesize option
  perf session: Don't warn about out of order event if write_backward is used
  perf tools: Enable overwrite settings
  ...

Linus Torvalds   commited 2016-07-25 13:20:41 -07:00
7e4dc77b28
x86/insn: remove pcommit
The pcommit instruction is being deprecated in favor of either ADR
(asynchronous DRAM refresh: flush-on-power-fail) at the platform level, or
posted-write-queue flush addresses as defined by the ACPI 6.x NFIT (NVDIMM
Firmware Interface Table).

Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: "H. Peter Anvin" <hpa@zytor.com>
Cc: x86@kernel.org
Cc: Josh Poimboeuf <jpoimboe@redhat.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Arnaldo Carvalho de Melo <acme@kernel.org>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Borislav Petkov <bp@suse.de>
Cc: Andy Lutomirski <luto@kernel.org>
Cc: Xiao Guangrong <guangrong.xiao@linux.intel.com>
Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: Ross Zwisler <ross.zwisler@linux.intel.com>
Acked-by: Ingo Molnar <mingo@redhat.com>
Signed-off-by: Dan Williams <dan.j.williams@intel.com>

Dan Williams   commited 2016-07-23 11:04:23 -07:00
fd1d961dd6
tools build: Fix objtool build with ARCH=x86_64
The objtool build fails in a cross-compiled environment on a non-x86
host with "ARCH=x86_64":

  tools/objtool/objtool-in.o: In function `decode_instructions':
  tools/objtool/builtin-check.c:276: undefined reference to `arch_decode_instruction'

We could override the ARCH environment variable and change it back to
x86, similar to what the objtool Makefile was doing before; but it's
tricky to override environment variables consistently.

Instead, take a similar approach used by the Linux top-level Makefile
and introduce a SRCARCH Makefile variable which evaluates to "x86" when
ARCH is either "x86_64" or "x86".

Reported-by: Stephen Rothwell <sfr@canb.auug.org.au>
Signed-off-by: Josh Poimboeuf <jpoimboe@redhat.com>
Cc: Andy Lutomirski <luto@amacapital.net>
Cc: H. Peter Anvin <hpa@zytor.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Link: http://lkml.kernel.org/r/20160722191920.ej62fnspnqurbaa7@treble
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>

Josh Poimboeuf   authored and   Arnaldo Carvalho de Melo   commited 2016-07-22 16:37:44 -03:00
60cbdf5d05
objtool: Always use host headers
From a conversation with Josh:

From http://lkml.kernel.org/r/20160722034118.guckaniobf3f7czc@treble :

It needs to be compiled with the host (powerpc) compiler, but then it
needs to disassemble target (x86) files.

 ----

So use HOSTARCH instead of ARCH.

Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: David Ahern <dsahern@gmail.com>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Josh Poimboeuf <jpoimboe@redhat.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Stephen Rothwell <sfr@canb.auug.org.au>
Cc: Wang Nan <wangnan0@huawei.com>
Link: http://lkml.kernel.org/r/20160722034118.guckaniobf3f7czc@treble
Link: http://lkml.kernel.org/n/tip-le1m1yzxnfpt3msbblu40nm8@git.kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>

Arnaldo Carvalho de Melo   commited 2016-07-22 16:28:46 -03:00
0cf6eb603b
objtool: Use tools/scripts/Makefile.arch to get ARCH and HOSTARCH
objtool's Makefile was setting up ARCH but fixing up just the x86_64 ->
x86, using Makefile.arch will do the necessary fixups for all arches.

Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: David Ahern <dsahern@gmail.com>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Josh Poimboeuf <jpoimboe@redhat.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Stephen Rothwell <sfr@canb.auug.org.au>
Cc: Wang Nan <wangnan0@huawei.com>
Link: http://lkml.kernel.org/n/tip-hbq0bbh03u2b722vozcyql31@git.kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>

Arnaldo Carvalho de Melo   commited 2016-07-22 16:28:25 -03:00
630e7a2904
objtool: Initialize variable to silence old compiler
gcc version 4.1.2 20080704 (Red Hat 4.1.2-55) barfs with:

    CC       /tmp/build/objtool/builtin-check.o
  cc1: warnings being treated as errors
  builtin-check.c: In function 'cmd_check':
  builtin-check.c:667: warning: 'prev_rela' may be used uninitialized in this function
  mv: cannot stat `/tmp/build/objtool/.builtin-check.o.tmp': No such file or directory
  make[1]: *** [/tmp/build/objtool/builtin-check.o] Error 1

Init it to NULL to silence it.

Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: David Ahern <dsahern@gmail.com>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Josh Poimboeuf <jpoimboe@redhat.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Wang Nan <wangnan0@huawei.com>
Link: http://lkml.kernel.org/n/tip-qolo31rl2ojlwj1lj9dhemyz@git.kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>

Arnaldo Carvalho de Melo   commited 2016-07-15 17:32:52 -03:00
b49364f36c
objtool: Add -I$(srctree)/tools/arch/$(ARCH)/include/uapi
So that it can find asm/bitsperlong.h to get the __BITS_PER_LONG
definition.

Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: David Ahern <dsahern@gmail.com>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Josh Poimboeuf <jpoimboe@redhat.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Wang Nan <wangnan0@huawei.com>
Link: http://lkml.kernel.org/n/tip-pr3pvskh65pey4po7t122z4j@git.kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>

Arnaldo Carvalho de Melo   commited 2016-07-15 17:29:20 -03:00
4a0982f941