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| author | Josh Poimboeuf <jpoimboe@redhat.com> | 2021-01-21 22:29:24 +0100 |
|---|---|---|
| committer | Josh Poimboeuf <jpoimboe@redhat.com> | 2021-01-26 18:12:00 +0100 |
| commit | b735bd3e68824316655252a931a3353a6ebc036f (patch) | |
| tree | 24a879a66b4ce0549a05d2aca3ec81dab212b128 /arch/x86/lib | |
| parent | objtool: Add asm version of STACK_FRAME_NON_STANDARD (diff) | |
| download | linux-b735bd3e68824316655252a931a3353a6ebc036f.tar.xz linux-b735bd3e68824316655252a931a3353a6ebc036f.zip | |
objtool: Combine UNWIND_HINT_RET_OFFSET and UNWIND_HINT_FUNC
The ORC metadata generated for UNWIND_HINT_FUNC isn't actually very
func-like. With certain usages it can cause stack state mismatches
because it doesn't set the return address (CFI_RA).
Also, users of UNWIND_HINT_RET_OFFSET no longer need to set a custom
return stack offset. Instead they just need to specify a func-like
situation, so the current ret_offset code is hacky for no good reason.
Solve both problems by simplifying the RET_OFFSET handling and
converting it into a more useful UNWIND_HINT_FUNC.
If we end up needing the old 'ret_offset' functionality again in the
future, we should be able to support it pretty easily with the addition
of a custom 'sp_offset' in UNWIND_HINT_FUNC.
Signed-off-by: Josh Poimboeuf <jpoimboe@redhat.com>
Link: https://lore.kernel.org/r/db9d1f5d79dddfbb3725ef6d8ec3477ad199948d.1611263462.git.jpoimboe@redhat.com
Diffstat (limited to 'arch/x86/lib')
| -rw-r--r-- | arch/x86/lib/retpoline.S | 2 |
1 files changed, 1 insertions, 1 deletions
diff --git a/arch/x86/lib/retpoline.S b/arch/x86/lib/retpoline.S index b4c43a9b1483..f6fb1d218dcc 100644 --- a/arch/x86/lib/retpoline.S +++ b/arch/x86/lib/retpoline.S @@ -28,7 +28,7 @@ SYM_FUNC_START_NOALIGN(__x86_retpoline_\reg) jmp .Lspec_trap_\@ .Ldo_rop_\@: mov %\reg, (%_ASM_SP) - UNWIND_HINT_RET_OFFSET + UNWIND_HINT_FUNC ret SYM_FUNC_END(__x86_retpoline_\reg) |