diff options
| author | Josh Poimboeuf <jpoimboe@redhat.com> | 2021-01-21 15:29:24 -0600 |
|---|---|---|
| committer | Josh Poimboeuf <jpoimboe@redhat.com> | 2021-01-26 11:12:00 -0600 |
| commit | b735bd3e68824316655252a931a3353a6ebc036f (patch) | |
| tree | 24a879a66b4ce0549a05d2aca3ec81dab212b128 /tools/objtool/arch | |
| parent | 081df94301e317e84c3413686043987da2c3e39d (diff) | |
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 'tools/objtool/arch')
| -rw-r--r-- | tools/objtool/arch/x86/decode.c | 4 |
1 files changed, 2 insertions, 2 deletions
diff --git a/tools/objtool/arch/x86/decode.c b/tools/objtool/arch/x86/decode.c index 6baa22732ca6..9637e3bf5ab8 100644 --- a/tools/objtool/arch/x86/decode.c +++ b/tools/objtool/arch/x86/decode.c @@ -563,8 +563,8 @@ void arch_initial_func_cfi_state(struct cfi_init_state *state) state->cfa.offset = 8; /* initial RA (return address) */ - state->regs[16].base = CFI_CFA; - state->regs[16].offset = -8; + state->regs[CFI_RA].base = CFI_CFA; + state->regs[CFI_RA].offset = -8; } const char *arch_nop_insn(int len) |