diff options
| author | Josh Poimboeuf <jpoimboe@redhat.com> | 2018-01-11 21:46:23 +0000 |
|---|---|---|
| committer | Thomas Gleixner <tglx@linutronix.de> | 2018-01-12 00:14:28 +0100 |
| commit | 39b735332cb8b33a27c28592d969e4016c86c3ea (patch) | |
| tree | 0a53711d68fc092321ee01f755a31e16585d754e /tools/objtool | |
| parent | 445b69e3b75e42362a5bdc13c8b8f61599e2228a (diff) | |
objtool: Detect jumps to retpoline thunks
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
Diffstat (limited to 'tools/objtool')
| -rw-r--r-- | tools/objtool/check.c | 7 |
1 files changed, 7 insertions, 0 deletions
diff --git a/tools/objtool/check.c b/tools/objtool/check.c index 9b341584eb1b..de053fb7049b 100644 --- a/tools/objtool/check.c +++ b/tools/objtool/check.c @@ -456,6 +456,13 @@ static int add_jump_destinations(struct objtool_file *file) } else if (rela->sym->sec->idx) { dest_sec = rela->sym->sec; dest_off = rela->sym->sym.st_value + rela->addend + 4; + } else if (strstr(rela->sym->name, "_indirect_thunk_")) { + /* + * Retpoline jumps are really dynamic jumps in + * disguise, so convert them accordingly. + */ + insn->type = INSN_JUMP_DYNAMIC; + continue; } else { /* sibling call */ insn->jump_dest = 0; |