Paolo Bonzini 44d5271707 KVM: LAPIC: ensure APIC map is up to date on concurrent update requests ... The following race can cause lost map update events: cpu1 cpu2 apic_map_dirty = true ------------------------------------------------------------ kvm_recalculate_apic_map: pass check mutex_lock(&kvm->arch.apic_map_lock); if (!kvm->arch.apic_map_dirty) and in process of updating map ------------------------------------------------------------- other calls to apic_map_dirty = true might be too late for affected cpu ------------------------------------------------------------- apic_map_dirty = false ------------------------------------------------------------- kvm_recalculate_apic_map: bail out on if (!kvm->arch.apic_map_dirty) To fix it, record the beginning of an update of the APIC map in apic_map_dirty. If another APIC map change switches apic_map_dirty back to DIRTY during the update, kvm_recalculate_apic_map should not make it CLEAN, and the other caller will go through the slow path. Reported-by: Igor Mammedov <imammedo@redhat.com> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>		2020-06-22 13:37:30 -04:00
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asm	KVM: LAPIC: ensure APIC map is up to date on concurrent update requests	2020-06-22 13:37:30 -04:00
uapi/asm	Merge branch 'x86/entry' into ras/core	2020-06-11 15:17:57 +02:00