diff options
| author | Radim Krčmář <rkrcmar@redhat.com> | 2015-02-12 21:41:33 +0300 |
|---|---|---|
| committer | Paolo Bonzini <pbonzini@redhat.com> | 2015-04-08 11:47:01 +0300 |
| commit | 3548a259f6990d8cb4f520e6c14f4b45b1f2fd38 (patch) | |
| tree | 05ccddb27cac89d62a30168d20b5a15a4f8e4f8f /arch/x86/kvm | |
| parent | 9ea369b032d87b88f1a47187b51ad4321dea5766 (diff) | |
| download | linux-3548a259f6990d8cb4f520e6c14f4b45b1f2fd38.tar.xz | |
KVM: x86: avoid logical_map when it is invalid
We want to support mixed modes and the easiest solution is to avoid
optimizing those weird and unlikely scenarios.
Signed-off-by: Radim Krčmář <rkrcmar@redhat.com>
Message-Id: <1423766494-26150-4-git-send-email-rkrcmar@redhat.com>
[Add comment above KVM_APIC_MODE_* defines. - Paolo]
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Diffstat (limited to 'arch/x86/kvm')
| -rw-r--r-- | arch/x86/kvm/lapic.c | 24 |
1 files changed, 23 insertions, 1 deletions
diff --git a/arch/x86/kvm/lapic.c b/arch/x86/kvm/lapic.c index d45f00ba7440..fa4bd89ea381 100644 --- a/arch/x86/kvm/lapic.c +++ b/arch/x86/kvm/lapic.c @@ -133,6 +133,14 @@ static inline int kvm_apic_id(struct kvm_lapic *apic) return (kvm_apic_get_reg(apic, APIC_ID) >> 24) & 0xff; } +/* The logical map is definitely wrong if we have multiple + * modes at the same time. (Physical map is always right.) + */ +static inline bool kvm_apic_logical_map_valid(struct kvm_apic_map *map) +{ + return !(map->mode & (map->mode - 1)); +} + static void recalculate_apic_map(struct kvm *kvm) { struct kvm_apic_map *new, *old = NULL; @@ -162,16 +170,19 @@ static void recalculate_apic_map(struct kvm *kvm) new->ldr_bits = 32; new->cid_shift = 16; new->cid_mask = new->lid_mask = 0xffff; + new->mode |= KVM_APIC_MODE_X2APIC; } else if (kvm_apic_get_reg(apic, APIC_LDR)) { if (kvm_apic_get_reg(apic, APIC_DFR) == APIC_DFR_CLUSTER) { new->cid_shift = 4; new->cid_mask = 0xf; new->lid_mask = 0xf; + new->mode |= KVM_APIC_MODE_XAPIC_CLUSTER; } else { new->cid_shift = 8; new->cid_mask = 0; new->lid_mask = 0xff; + new->mode |= KVM_APIC_MODE_XAPIC_FLAT; } } @@ -201,6 +212,10 @@ static void recalculate_apic_map(struct kvm *kvm) if (aid < ARRAY_SIZE(new->phys_map)) new->phys_map[aid] = apic; + + if (!kvm_apic_logical_map_valid(new)); + continue; + if (lid && cid < ARRAY_SIZE(new->logical_map)) new->logical_map[cid][ffs(lid) - 1] = apic; } @@ -718,7 +733,14 @@ bool kvm_irq_delivery_to_apic_fast(struct kvm *kvm, struct kvm_lapic *src, dst = &map->phys_map[irq->dest_id]; } else { u32 mda = irq->dest_id << (32 - map->ldr_bits); - u16 cid = apic_cluster_id(map, mda); + u16 cid; + + if (!kvm_apic_logical_map_valid(map)) { + ret = false; + goto out; + } + + cid = apic_cluster_id(map, mda); if (cid >= ARRAY_SIZE(map->logical_map)) goto out; |