]> git.proxmox.com Git - mirror_ubuntu-focal-kernel.git/commit - tools/objtool/check.c
objtool: Detect jumps to retpoline thunks
authorJosh Poimboeuf <jpoimboe@redhat.com>
Thu, 11 Jan 2018 21:46:23 +0000 (21:46 +0000)
committerThomas Gleixner <tglx@linutronix.de>
Thu, 11 Jan 2018 23:14:28 +0000 (00:14 +0100)
commit39b735332cb8b33a27c28592d969e4016c86c3ea
tree0a53711d68fc092321ee01f755a31e16585d754e
parent445b69e3b75e42362a5bdc13c8b8f61599e2228a
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
tools/objtool/check.c