| Message ID | 161399212333.20312.15799180882369631665.tip-bot2@tip-bot2 |
|---|---|
| State | Accepted |
| Commit | 724c8a23d589d8a002d2e39633c2f9a5a429616f |
| Headers | show |
| Series |
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| Related | show |
diff --git a/tools/objtool/check.c b/tools/objtool/check.c index 62cd211..d7f1496 100644 --- a/tools/objtool/check.c +++ b/tools/objtool/check.c @@ -1983,6 +1983,20 @@ static int update_cfi_state(struct instruction *insn, struct cfi_state *cfi, } } + else if (op->dest.reg == CFI_SP && + cfi->vals[op->src.reg].base == CFI_SP_INDIRECT && + cfi->vals[op->src.reg].offset == cfa->offset) { + + /* + * The same stack swizzle case 2) as above. But + * because we can't change cfa->base, case 3) + * will become a regular POP. Pretend we're a + * PUSH so things don't go unbalanced. + */ + cfi->stack_size += 8; + } + + break; case OP_SRC_ADD:
The following commit has been merged into the objtool/core branch of tip: Commit-ID: 23e34c5988088b8bb4c55905973ca76114cb33ee Gitweb: https://git.kernel.org/tip/23e34c5988088b8bb4c55905973ca76114cb33ee Author: Peter Zijlstra <peterz@infradead.org> AuthorDate: Thu, 18 Feb 2021 17:14:10 +01:00 Committer: Peter Zijlstra <peterz@infradead.org> CommitterDate: Mon, 22 Feb 2021 12:05:18 +01:00 objtool: Fix stack-swizzle for FRAME_POINTER=y When objtool encounters the stack-swizzle: mov %rsp, (%[tos]) mov %[tos], %rsp ... pop %rsp Inside a FRAME_POINTER=y build, things go a little screwy because clearly we're not adjusting the cfa->base. This then results in the pop %rsp not being detected as a restore of cfa->base so it will turn into a regular POP and offset the stack, resulting in: kernel/softirq.o: warning: objtool: do_softirq()+0xdb: return with modified stack frame Therefore, have "mov %[tos], %rsp" act like a PUSH (it sorta is anyway) to balance the things out. We're not too concerned with the actual stack_size for frame-pointer builds, since we don't generate ORC data for them anyway. Fixes: aafeb14e9da2 ("objtool: Support stack-swizzle") Reported-by: kernel test robot <lkp@intel.com> Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Acked-by: Josh Poimboeuf <jpoimboe@redhat.com> Link: https://lkml.kernel.org/r/YC6UC+rc9KKmQrkd@hirez.programming.kicks-ass.net --- tools/objtool/check.c | 14 ++++++++++++++ 1 file changed, 14 insertions(+)