5c2a9f06a9
kvm -cpu host passes the original cpuid info to the guest. Latest kvm version seem to return true for mwait_leaf cpuid function on recent Intel CPUs. But it does not return mwait C-states (mwait_substates), instead zero is returned. While real CPUs seem to always return non-zero values, the intel idle driver should not get active in kvm (mwait_substates == 0) case and bail out. Otherwise a Null pointer exception will happen later when the cpuidle subsystem tries to get active: [0.984807] BUG: unable to handle kernel NULL pointer dereference at (null) [0.984807] IP: [<(null)>] (null) ... [0.984807][<ffffffff8143cf34>] ? cpuidle_idle_call+0xb4/0x340 [0.984807][<ffffffff8159e7bc>] ? __atomic_notifier_call_chain+0x4c/0x70 [0.984807][<ffffffff81001198>] ? cpu_idle+0x78/0xd0 Reference: https://bugzilla.novell.com/show_bug.cgi?id=726296 Cc: stable@vger.kernel.org Signed-off-by: Thomas Renninger <trenn@suse.de> CC: Bruno Friedmann <bruno@ioda-net.ch> Signed-off-by: Len Brown <len.brown@intel.com> |
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| .. | ||
| i7300_idle.c | ||
| intel_idle.c | ||
| Kconfig | ||
| Makefile | ||