From e3d72e8eee53c55835ab4664920d83400ff5d6c2 Mon Sep 17 00:00:00 2001 From: Borislav Petkov Date: Wed, 3 Nov 2021 10:30:29 +0100 Subject: [PATCH] x86/mce: Mark mce_start() noinstr Fixes vmlinux.o: warning: objtool: do_machine_check()+0x4ae: call to __const_udelay() leaves .noinstr.text section Signed-off-by: Borislav Petkov Link: https://lore.kernel.org/r/20211208111343.8130-13-bp@alien8.de --- arch/x86/kernel/cpu/mce/core.c | 20 ++++++++++++++------ 1 file changed, 14 insertions(+), 6 deletions(-) diff --git a/arch/x86/kernel/cpu/mce/core.c b/arch/x86/kernel/cpu/mce/core.c index 7023d65..5818b83 100644 --- a/arch/x86/kernel/cpu/mce/core.c +++ b/arch/x86/kernel/cpu/mce/core.c @@ -1007,13 +1007,13 @@ static atomic_t global_nwo; * in the entry order. * TBD double check parallel CPU hotunplug */ -static int mce_start(int *no_way_out) +static noinstr int mce_start(int *no_way_out) { - int order; u64 timeout = (u64)mca_cfg.monarch_timeout * NSEC_PER_USEC; + int order, ret = -1; if (!timeout) - return -1; + return ret; atomic_add(*no_way_out, &global_nwo); /* @@ -1023,6 +1023,9 @@ static int mce_start(int *no_way_out) order = atomic_inc_return(&mce_callin); cpumask_clear_cpu(smp_processor_id(), &mce_missing_cpus); + /* Enable instrumentation around calls to external facilities */ + instrumentation_begin(); + /* * Wait for everyone. */ @@ -1030,7 +1033,7 @@ static int mce_start(int *no_way_out) if (mce_timed_out(&timeout, "Timeout: Not all CPUs entered broadcast exception handler")) { atomic_set(&global_nwo, 0); - return -1; + goto out; } ndelay(SPINUNIT); } @@ -1056,7 +1059,7 @@ static int mce_start(int *no_way_out) if (mce_timed_out(&timeout, "Timeout: Subject CPUs unable to finish machine check processing")) { atomic_set(&global_nwo, 0); - return -1; + goto out; } ndelay(SPINUNIT); } @@ -1067,7 +1070,12 @@ static int mce_start(int *no_way_out) */ *no_way_out = atomic_read(&global_nwo); - return order; + ret = order; + +out: + instrumentation_end(); + + return ret; } /* -- 2.7.4