diff options
| author | Mark Brown <broonie@linaro.org> | 2014-01-17 15:52:17 +0000 |
|---|---|---|
| committer | Mark Brown <broonie@linaro.org> | 2014-01-17 15:52:17 +0000 |
| commit | 81e53d0470878165a300d75ac06a5bc5eee543a2 (patch) | |
| tree | 5fdaacfb350c5a290109f98ab29e9858f1f11469 /arch/x86/kernel/reboot.c | |
| parent | 15e0964dc2a097de3cf518badf2237b6b6adf7fe (diff) | |
| parent | fcb4ed749c776a2ae89ca40343cbccb6f8981e60 (diff) | |
Merge branches 'topic/sc18is602' and 'topic/rspi' of git://git.kernel.org/pub/scm/linux/kernel/git/broonie/spi into spi-bpw
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 |