From: Peter Zijlstra <peterz@xxxxxxxxxxxxx> [ Upstream commit f9cdf7ca57cada055f61ef6d0eb4db21c3f200db ] vmlinux.o: warning: objtool: smp_stop_nmi_callback()+0x2b: unreachable instruction 0000 0000000000047cf0 <smp_stop_nmi_callback>: ... 0026 47d16: e8 00 00 00 00 call 47d1b <smp_stop_nmi_callback+0x2b> 47d17: R_X86_64_PLT32 stop_this_cpu-0x4 002b 47d1b: b8 01 00 00 00 mov $0x1,%eax Signed-off-by: Peter Zijlstra (Intel) <peterz@xxxxxxxxxxxxx> Acked-by: Josh Poimboeuf <jpoimboe@xxxxxxxxxx> Link: https://lore.kernel.org/r/20220308154319.290905453@xxxxxxxxxxxxx Stable-dep-of: c0dd9245aa9e ("x86/microcode: Check CPU capabilities after late microcode update correctly") Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx> --- arch/x86/include/asm/processor.h | 2 +- arch/x86/kernel/process.c | 2 +- tools/objtool/check.c | 1 + 3 files changed, 3 insertions(+), 2 deletions(-) diff --git a/arch/x86/include/asm/processor.h b/arch/x86/include/asm/processor.h index 577f342dbfb27..5c7904c97a1a7 100644 --- a/arch/x86/include/asm/processor.h +++ b/arch/x86/include/asm/processor.h @@ -834,7 +834,7 @@ bool xen_set_default_idle(void); #define xen_set_default_idle 0 #endif -void stop_this_cpu(void *dummy); +void __noreturn stop_this_cpu(void *dummy); void microcode_check(void); enum l1tf_mitigations { diff --git a/arch/x86/kernel/process.c b/arch/x86/kernel/process.c index bc9b4b93cf9bc..e6b28c689e9a9 100644 --- a/arch/x86/kernel/process.c +++ b/arch/x86/kernel/process.c @@ -731,7 +731,7 @@ bool xen_set_default_idle(void) } #endif -void stop_this_cpu(void *dummy) +void __noreturn stop_this_cpu(void *dummy) { local_irq_disable(); /* diff --git a/tools/objtool/check.c b/tools/objtool/check.c index 758c0ba8de350..3ef767284b3f0 100644 --- a/tools/objtool/check.c +++ b/tools/objtool/check.c @@ -181,6 +181,7 @@ static bool __dead_end_function(struct objtool_file *file, struct symbol *func, "kunit_try_catch_throw", "xen_start_kernel", "cpu_bringup_and_idle", + "stop_this_cpu", }; if (!func) -- 2.39.2
