From: Fenghua Yu Date: Thu, 24 Oct 2013 01:30:12 +0000 (-0700) Subject: x86/apic: Disable I/O APIC before shutdown of the local APIC X-Git-Tag: v3.4.92~89 X-Git-Url: http://git.ipfire.org/gitweb.cgi?a=commitdiff_plain;h=570a73ebc127470b325a39f5d8b18eeedb05cc58;p=thirdparty%2Fkernel%2Fstable.git x86/apic: Disable I/O APIC before shutdown of the local APIC commit 522e66464467543c0d88d023336eec4df03ad40b upstream. In reboot and crash path, when we shut down the local APIC, the I/O APIC is still active. This may cause issues because external interrupts can still come in and disturb the local APIC during shutdown process. To quiet external interrupts, disable I/O APIC before shutdown local APIC. Signed-off-by: Fenghua Yu Link: http://lkml.kernel.org/r/1382578212-4677-1-git-send-email-fenghua.yu@intel.com [ I suppose the 'issue' is a hang during shutdown. It's a fine change nevertheless. ] Signed-off-by: Ingo Molnar [bwh: Backported to 3.2: adjust context] Signed-off-by: Ben Hutchings Cc: Rui Xiang Signed-off-by: Greg Kroah-Hartman --- diff --git a/arch/x86/kernel/crash.c b/arch/x86/kernel/crash.c index 13ad89971d474..69e231b9d925c 100644 --- a/arch/x86/kernel/crash.c +++ b/arch/x86/kernel/crash.c @@ -95,10 +95,10 @@ void native_machine_crash_shutdown(struct pt_regs *regs) cpu_emergency_vmxoff(); cpu_emergency_svm_disable(); - lapic_shutdown(); #if defined(CONFIG_X86_IO_APIC) disable_IO_APIC(); #endif + lapic_shutdown(); #ifdef CONFIG_HPET_TIMER hpet_disable(); #endif diff --git a/arch/x86/kernel/reboot.c b/arch/x86/kernel/reboot.c index bd70df6162f7a..d398f317f5e04 100644 --- a/arch/x86/kernel/reboot.c +++ b/arch/x86/kernel/reboot.c @@ -668,6 +668,13 @@ void native_machine_shutdown(void) /* The boot cpu is always logical cpu 0 */ int reboot_cpu_id = 0; +#endif + +#ifdef CONFIG_X86_IO_APIC + disable_IO_APIC(); +#endif + +#ifdef CONFIG_SMP #ifdef CONFIG_X86_32 /* See if there has been given a command line override */ @@ -691,10 +698,6 @@ void native_machine_shutdown(void) lapic_shutdown(); -#ifdef CONFIG_X86_IO_APIC - disable_IO_APIC(); -#endif - #ifdef CONFIG_HPET_TIMER hpet_disable(); #endif