[PATCH v3 17/28] x86/entry: Make rewind_stack_and_make_dead() a real function
From: Josh Poimboeuf <jpoimboe@kernel.org>
Date: 2026-09-21 22:31:46
Also in:
lkml, rust-for-linux
Subsystem:
objtool, the rest, x86 architecture (32-bit and 64-bit), x86 entry code · Maintainers:
Josh Poimboeuf, Peter Zijlstra, Linus Torvalds, Thomas Gleixner, Ingo Molnar, Borislav Petkov, Dave Hansen, Andy Lutomirski
rewind_stack_and_make_dead() is SYM_CODE because it switches stacks, but it's otherwise a callable function from C. Convert it to SYM_FUNC so objtool can detect that it's noreturn and its entry can be removed from the hard-coded global noreturns list. Signed-off-by: Josh Poimboeuf <jpoimboe@kernel.org> --- arch/x86/entry/entry_64.S | 7 +++---- tools/objtool/noreturns.h | 1 - 2 files changed, 3 insertions(+), 5 deletions(-)
diff --git a/arch/x86/entry/entry_64.S b/arch/x86/entry/entry_64.S
index 253f0a585927f..2f4d930d9977d 100644
--- a/arch/x86/entry/entry_64.S
+++ b/arch/x86/entry/entry_64.S@@ -1486,9 +1486,7 @@ SYM_CODE_START(entry_SYSCALL32_ignore) SYM_CODE_END(entry_SYSCALL32_ignore) .pushsection .text, "ax" - __FUNC_ALIGN -SYM_CODE_START_NOALIGN(rewind_stack_and_make_dead) - UNWIND_HINT_FUNC +SYM_FUNC_START(rewind_stack_and_make_dead) /* Prevent any naive code from trying to unwind to our caller. */ xorl %ebp, %ebp
@@ -1497,7 +1495,8 @@ SYM_CODE_START_NOALIGN(rewind_stack_and_make_dead) UNWIND_HINT_REGS call make_task_dead -SYM_CODE_END(rewind_stack_and_make_dead) +SYM_FUNC_END(rewind_stack_and_make_dead) +STACK_FRAME_NON_STANDARD_FP(rewind_stack_and_make_dead) .popsection /*
diff --git a/tools/objtool/noreturns.h b/tools/objtool/noreturns.h
index 26f62f98bc8ef..ff93e94ee09a0 100644
--- a/tools/objtool/noreturns.h
+++ b/tools/objtool/noreturns.h@@ -19,7 +19,6 @@ NORETURN(kunit_try_catch_throw) NORETURN(mpt_halt_firmware) NORETURN(panic) NORETURN(vpanic) -NORETURN(rewind_stack_and_make_dead) NORETURN(rust_helper_BUG) NORETURN(sev_es_terminate) NORETURN(xen_cpu_bringup_again)
--
2.55.0