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authorMark Brown <broonie@linaro.org>2013-12-31 12:59:55 +0000
committerMark Brown <broonie@linaro.org>2013-12-31 12:59:55 +0000
commit68066bb378a0504439e046cdb55d88362eb6379d (patch)
tree0b60f72ddf7108a63dd4db617b42e07fbae5346d /arch/x86/kernel/reboot.c
parent43f627ac9de42607b2cdcc7a41f2bcc82187e06a (diff)
parent802eee95bde72fd0cd0f3a5b2098375a487d1eda (diff)
Merge tag 'v3.13-rc6' into spi-dw
To resolve trivial overlaps with fixes. Linux 3.13-rc6
Diffstat (limited to 'arch/x86/kernel/reboot.c')
-rw-r--r--arch/x86/kernel/reboot.c11
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