diff options
| author | Josh Poimboeuf <jpoimboe@redhat.com> | 2021-01-22 00:29:24 +0300 |
|---|---|---|
| committer | Josh Poimboeuf <jpoimboe@redhat.com> | 2021-01-26 20:12:00 +0300 |
| commit | b735bd3e68824316655252a931a3353a6ebc036f (patch) | |
| tree | 24a879a66b4ce0549a05d2aca3ec81dab212b128 /arch/x86/kernel/ftrace_64.S | |
| parent | 081df94301e317e84c3413686043987da2c3e39d (diff) | |
| download | linux-b735bd3e68824316655252a931a3353a6ebc036f.tar.xz | |
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/kernel/ftrace_64.S')
| -rw-r--r-- | arch/x86/kernel/ftrace_64.S | 2 |
1 files changed, 1 insertions, 1 deletions
diff --git a/arch/x86/kernel/ftrace_64.S b/arch/x86/kernel/ftrace_64.S index 58d125ed9d1a..1bf568d901b1 100644 --- a/arch/x86/kernel/ftrace_64.S +++ b/arch/x86/kernel/ftrace_64.S @@ -277,7 +277,7 @@ SYM_INNER_LABEL(ftrace_regs_caller_end, SYM_L_GLOBAL) restore_mcount_regs 8 /* Restore flags */ popfq - UNWIND_HINT_RET_OFFSET + UNWIND_HINT_FUNC jmp ftrace_epilogue SYM_FUNC_END(ftrace_regs_caller) |