Commit Graph

5 Commits

Author SHA1 Message Date
Josh Poimboeuf 8782e7cab5 objtool: Support Clang non-section symbols in ORC dump
Historically, the relocation symbols for ORC entries have only been
section symbols:

  .text+0: sp:sp+8 bp:(und) type:call end:0

However, the Clang assembler is aggressive about stripping section
symbols.  In that case we will need to use function symbols:

  freezing_slow_path+0: sp:sp+8 bp:(und) type:call end:0

In preparation for the generation of such entries in "objtool orc
generate", add support for reading them in "objtool orc dump".

Signed-off-by: Josh Poimboeuf <jpoimboe@redhat.com>
Signed-off-by: Borislav Petkov <bp@suse.de>
Reviewed-by: Miroslav Benes <mbenes@suse.cz>
Acked-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Link: https://lkml.kernel.org/r/b811b5eb1a42602c3b523576dc5efab9ad1c174d.1585761021.git.jpoimboe@redhat.com
2020-04-14 11:59:52 +02:00
Thomas Gleixner 1ccea77e2a treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 13
Based on 2 normalized pattern(s):

  this program is free software you can redistribute it and or modify
  it under the terms of the gnu general public license as published by
  the free software foundation either version 2 of the license or at
  your option any later version this program is distributed in the
  hope that it will be useful but without any warranty without even
  the implied warranty of merchantability or fitness for a particular
  purpose see the gnu general public license for more details you
  should have received a copy of the gnu general public license along
  with this program if not see http www gnu org licenses

  this program is free software you can redistribute it and or modify
  it under the terms of the gnu general public license as published by
  the free software foundation either version 2 of the license or at
  your option any later version this program is distributed in the
  hope that it will be useful but without any warranty without even
  the implied warranty of merchantability or fitness for a particular
  purpose see the gnu general public license for more details [based]
  [from] [clk] [highbank] [c] you should have received a copy of the
  gnu general public license along with this program if not see http
  www gnu org licenses

extracted by the scancode license scanner the SPDX license identifier

  GPL-2.0-or-later

has been chosen to replace the boilerplate/reference in 355 file(s).

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Kate Stewart <kstewart@linuxfoundation.org>
Reviewed-by: Jilayne Lovejoy <opensource@jilayne.com>
Reviewed-by: Steve Winslow <swinslow@gmail.com>
Reviewed-by: Allison Randal <allison@lohutok.net>
Cc: linux-spdx@vger.kernel.org
Link: https://lkml.kernel.org/r/20190519154041.837383322@linutronix.de
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2019-05-21 11:28:45 +02:00
Josh Poimboeuf d31a580266 x86/unwind/orc: Detect the end of the stack
The existing UNWIND_HINT_EMPTY annotations happen to be good indicators
of where entry code calls into C code for the first time.  So also use
them to mark the end of the stack for the ORC unwinder.

Use that information to set unwind->error if the ORC unwinder doesn't
unwind all the way to the end.  This will be needed for enabling
HAVE_RELIABLE_STACKTRACE for the ORC unwinder so we can use it with the
livepatch consistency model.

Thanks to Jiri Slaby for teaching the ORCs about the unwind hints.

Signed-off-by: Josh Poimboeuf <jpoimboe@redhat.com>
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: https://lkml.kernel.org/lkml/20180518064713.26440-5-jslaby@suse.cz
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2018-06-21 16:34:56 +02:00
Mikulas Patocka 14c47b54b0 objtool: Fix 64-bit build on 32-bit host
The new ORC unwinder breaks the build of a 64-bit kernel on a 32-bit
host.  Building the kernel on a i386 or x32 host fails with:

  orc_dump.c: In function 'orc_dump':
  orc_dump.c:105:26: error: passing argument 2 of 'elf_getshdrnum' from incompatible pointer type [-Werror=incompatible-pointer-types]
    if (elf_getshdrnum(elf, &nr_sections)) {
                            ^
  In file included from /usr/local/include/gelf.h:32:0,
                   from elf.h:22,
                   from warn.h:26,
                   from orc_dump.c:20:
  /usr/local/include/libelf.h:304:12: note: expected 'size_t * {aka unsigned int *}' but argument is of type 'long unsigned int *'
   extern int elf_getshdrnum (Elf *__elf, size_t *__dst);
              ^~~~~~~~~~~~~~
  orc_dump.c:190:17: error: format '%lx' expects argument of type 'long unsigned int', but argument 3 has type 'Elf64_Sxword {aka long long int}' [-Werror=format=]
      printf("%s+%lx:", name, rela.r_addend);
                 ~~^          ~~~~~~~~~~~~~
                 %llx

Fix the build failure.

Another problem is that if the user specifies HOSTCC or HOSTLD
variables, they are ignored in the objtool makefile.  Change the
Makefile to respect these variables.

Signed-off-by: Mikulas Patocka <mpatocka@redhat.com>
Signed-off-by: Josh Poimboeuf <jpoimboe@redhat.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Sven Joachim <svenjoac@gmx.de>
Cc: Thomas Gleixner <tglx@linutronix.de>
Fixes: 627fce1480 ("objtool: Add ORC unwind table generation")
Link: http://lkml.kernel.org/r/19f0e64d8e07e30a7b307cd010eb780c404fe08d.1512252895.git.jpoimboe@redhat.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2017-12-06 22:38:14 +01:00
Josh Poimboeuf 627fce1480 objtool: Add ORC unwind table generation
Now that objtool knows the states of all registers on the stack for each
instruction, it's straightforward to generate debuginfo for an unwinder
to use.

Instead of generating DWARF, generate a new format called ORC, which is
more suitable for an in-kernel unwinder.  See
Documentation/x86/orc-unwinder.txt for a more detailed description of
this new debuginfo format and why it's preferable to DWARF.

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: Jiri Slaby <jslaby@suse.cz>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Mike Galbraith <efault@gmx.de>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: live-patching@vger.kernel.org
Link: http://lkml.kernel.org/r/c9b9f01ba6c5ed2bdc9bb0957b78167fdbf9632e.1499786555.git.jpoimboe@redhat.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2017-07-18 10:57:43 +02:00