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| author | Julien Thierry <jthierry@redhat.com> | 2020-10-14 08:38:02 +0100 |
|---|---|---|
| committer | Josh Poimboeuf <jpoimboe@redhat.com> | 2021-01-13 18:13:10 -0600 |
| commit | 201ef5a974e24112953b74cc9f33dcfc4cbcc1cb (patch) | |
| tree | 5550866c1f4b6fdc2e026c9aed3cd3c89958054e /tools/objtool | |
| parent | 468af56a7bbaa626da5a4578bedc930d731fba13 (diff) | |
| download | linux-201ef5a974e24112953b74cc9f33dcfc4cbcc1cb.tar.gz | |
objtool: Make SP memory operation match PUSH/POP semantics
Architectures without PUSH/POP instructions will always access the stack though memory operations (SRC/DEST_INDIRECT). Make those operations have the same effect on the CFA as PUSH/POP, with no stack pointer modification. Signed-off-by: Julien Thierry <jthierry@redhat.com> Acked-by: Peter Zijlstra (Intel) <peterz@infradead.org> Signed-off-by: Josh Poimboeuf <jpoimboe@redhat.com>
Diffstat (limited to 'tools/objtool')
| -rw-r--r-- | tools/objtool/check.c | 20 |
1 files changed, 20 insertions, 0 deletions
diff --git a/tools/objtool/check.c b/tools/objtool/check.c index 00d00f904536..270adc38d896 100644 --- a/tools/objtool/check.c +++ b/tools/objtool/check.c @@ -2065,6 +2065,14 @@ static int update_cfi_state(struct instruction *insn, struct cfi_state *cfi, break; case OP_SRC_REG_INDIRECT: + if (!cfi->drap && op->dest.reg == cfa->base && + op->dest.reg == CFI_BP) { + + /* mov disp(%rsp), %rbp */ + cfa->base = CFI_SP; + cfa->offset = cfi->stack_size; + } + if (cfi->drap && op->src.reg == CFI_BP && op->src.offset == cfi->drap_offset) { @@ -2086,6 +2094,12 @@ static int update_cfi_state(struct instruction *insn, struct cfi_state *cfi, /* mov disp(%rbp), %reg */ /* mov disp(%rsp), %reg */ restore_reg(cfi, op->dest.reg); + + } else if (op->src.reg == CFI_SP && + op->src.offset == regs[op->dest.reg].offset + cfi->stack_size) { + + /* mov disp(%rsp), %reg */ + restore_reg(cfi, op->dest.reg); } break; @@ -2163,6 +2177,12 @@ static int update_cfi_state(struct instruction *insn, struct cfi_state *cfi, /* mov reg, disp(%rsp) */ save_reg(cfi, op->src.reg, CFI_CFA, op->dest.offset - cfi->cfa.offset); + + } else if (op->dest.reg == CFI_SP) { + + /* mov reg, disp(%rsp) */ + save_reg(cfi, op->src.reg, CFI_CFA, + op->dest.offset - cfi->stack_size); } break; |