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| author | Mark Brown <broonie@linaro.org> | 2014-01-14 14:14:47 +0000 |
|---|---|---|
| committer | Mark Brown <broonie@linaro.org> | 2014-01-14 14:14:47 +0000 |
| commit | 13ea3300100ec3461560b1e061033cd167333a86 (patch) | |
| tree | c60a016a06c488adada6959516e2a2de96d6d7d3 /arch/x86/kernel/reboot.c | |
| parent | b7ed6b88b2a5e961eeb939ef637a3cbb435a23a7 (diff) | |
| parent | 68e67d97e1f91ed11e041b67f3a1336f518c608f (diff) | |
Merge branch 'topic/rcar' of git://git.kernel.org/pub/scm/linux/kernel/git/broonie/spi into spi-rspi
Diffstat (limited to 'arch/x86/kernel/reboot.c')
| -rw-r--r-- | arch/x86/kernel/reboot.c | 11 |
1 files changed, 11 insertions, 0 deletions
diff --git a/arch/x86/kernel/reboot.c b/arch/x86/kernel/reboot.c index da3c599584a..c752cb43e52 100644 --- a/arch/x86/kernel/reboot.c +++ b/arch/x86/kernel/reboot.c @@ -558,6 +558,17 @@ void native_machine_shutdown(void) { /* Stop the cpus and apics */ #ifdef CONFIG_X86_IO_APIC + /* + * Disabling IO APIC before local APIC is a workaround for + * erratum AVR31 in "Intel Atom Processor C2000 Product Family + * Specification Update". In this situation, interrupts that target + * a Logical Processor whose Local APIC is either in the process of + * being hardware disabled or software disabled are neither delivered + * nor discarded. When this erratum occurs, the processor may hang. + * + * Even without the erratum, it still makes sense to quiet IO APIC + * before disabling Local APIC. + */ disable_IO_APIC(); #endif |