diff options
| author | Peter Zijlstra <peterz@infradead.org> | 2021-06-10 09:04:29 +0200 |
|---|---|---|
| committer | Greg Kroah-Hartman <gregkh@linuxfoundation.org> | 2022-07-25 11:26:19 +0200 |
| commit | e32542e9ed362bf8ea48941d965495e1593b5cef (patch) | |
| tree | c796ea79e917dfc1173f4d2fa50f511aeb7afcc3 /tools/objtool | |
| parent | a0319253825ebd8c5b19e31902c4f35f85e93285 (diff) | |
objtool: Only rewrite unconditional retpoline thunk calls
commit 2d49b721dc18c113d5221f4cf5a6104eb66cb7f2 upstream.
It turns out that the compilers generate conditional branches to the
retpoline thunks like:
5d5: 0f 85 00 00 00 00 jne 5db <cpuidle_reflect+0x22>
5d7: R_X86_64_PLT32 __x86_indirect_thunk_r11-0x4
while the rewrite can only handle JMP/CALL to the thunks. The result
is the alternative wrecking the code. Make sure to skip writing the
alternatives for conditional branches.
Fixes: 9bc0bb50727c ("objtool/x86: Rewrite retpoline thunk calls")
Reported-by: Lukasz Majczak <lma@semihalf.com>
Reported-by: Nathan Chancellor <nathan@kernel.org>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Tested-by: Nathan Chancellor <nathan@kernel.org>
Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Diffstat (limited to 'tools/objtool')
| -rw-r--r-- | tools/objtool/arch/x86/decode.c | 4 |
1 files changed, 4 insertions, 0 deletions
diff --git a/tools/objtool/arch/x86/decode.c b/tools/objtool/arch/x86/decode.c index 4154921291d0..09035e28f472 100644 --- a/tools/objtool/arch/x86/decode.c +++ b/tools/objtool/arch/x86/decode.c @@ -674,6 +674,10 @@ int arch_rewrite_retpolines(struct objtool_file *file) list_for_each_entry(insn, &file->retpoline_call_list, call_node) { + if (insn->type != INSN_JUMP_DYNAMIC && + insn->type != INSN_CALL_DYNAMIC) + continue; + if (!strcmp(insn->sec->name, ".text.__x86.indirect_thunk")) continue; |