aboutsummaryrefslogtreecommitdiffstats
diff options
context:
space:
mode:
authorBenjamin Herrenschmidt <benh@kernel.crashing.org>2012-03-23 11:21:14 +1100
committerAlexander Graf <agraf@suse.de>2012-05-16 15:02:11 +0200
commitffe3649282946547f1b938e02c0228aead407a18 (patch)
treebc95604d39cdefb135adc60c03fabffda4557604
parent32c7dbfd479e73684b0d23fcb0a5cb04f19d86f4 (diff)
downloadlinux-cve-tagged-ffe3649282946547f1b938e02c0228aead407a18.tar.gz
powerpc/kvm: Fix VSID usage in 64-bit "PR" KVM
The code forgot to scramble the VSIDs the way we normally do and was basically using the "proto VSID" directly with the MMU. This means that in practice, KVM used random VSIDs that could collide with segments used by other user space programs. Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org> [agraf: simplify ppc32 case] Signed-off-by: Alexander Graf <agraf@suse.de>
-rw-r--r--arch/powerpc/include/asm/kvm_book3s.h7
-rw-r--r--arch/powerpc/kvm/book3s_64_mmu_host.c13
2 files changed, 11 insertions, 9 deletions
diff --git a/arch/powerpc/include/asm/kvm_book3s.h b/arch/powerpc/include/asm/kvm_book3s.h
index aa795ccef2942f..fd07f43d66224c 100644
--- a/arch/powerpc/include/asm/kvm_book3s.h
+++ b/arch/powerpc/include/asm/kvm_book3s.h
@@ -81,12 +81,13 @@ struct kvmppc_vcpu_book3s {
u64 sdr1;
u64 hior;
u64 msr_mask;
- u64 vsid_next;
#ifdef CONFIG_PPC_BOOK3S_32
u32 vsid_pool[VSID_POOL_SIZE];
+ u32 vsid_next;
#else
- u64 vsid_first;
- u64 vsid_max;
+ u64 proto_vsid_first;
+ u64 proto_vsid_max;
+ u64 proto_vsid_next;
#endif
int context_id[SID_CONTEXTS];
diff --git a/arch/powerpc/kvm/book3s_64_mmu_host.c b/arch/powerpc/kvm/book3s_64_mmu_host.c
index 6f87f39a1ac21c..10fc8ec9d2a8b7 100644
--- a/arch/powerpc/kvm/book3s_64_mmu_host.c
+++ b/arch/powerpc/kvm/book3s_64_mmu_host.c
@@ -194,14 +194,14 @@ static struct kvmppc_sid_map *create_sid_map(struct kvm_vcpu *vcpu, u64 gvsid)
backwards_map = !backwards_map;
/* Uh-oh ... out of mappings. Let's flush! */
- if (vcpu_book3s->vsid_next == vcpu_book3s->vsid_max) {
- vcpu_book3s->vsid_next = vcpu_book3s->vsid_first;
+ if (vcpu_book3s->proto_vsid_next == vcpu_book3s->proto_vsid_max) {
+ vcpu_book3s->proto_vsid_next = vcpu_book3s->proto_vsid_first;
memset(vcpu_book3s->sid_map, 0,
sizeof(struct kvmppc_sid_map) * SID_MAP_NUM);
kvmppc_mmu_pte_flush(vcpu, 0, 0);
kvmppc_mmu_flush_segments(vcpu);
}
- map->host_vsid = vcpu_book3s->vsid_next++;
+ map->host_vsid = vsid_scramble(vcpu_book3s->proto_vsid_next++, 256M);
map->guest_vsid = gvsid;
map->valid = true;
@@ -319,9 +319,10 @@ int kvmppc_mmu_init(struct kvm_vcpu *vcpu)
return -1;
vcpu3s->context_id[0] = err;
- vcpu3s->vsid_max = ((vcpu3s->context_id[0] + 1) << USER_ESID_BITS) - 1;
- vcpu3s->vsid_first = vcpu3s->context_id[0] << USER_ESID_BITS;
- vcpu3s->vsid_next = vcpu3s->vsid_first;
+ vcpu3s->proto_vsid_max = ((vcpu3s->context_id[0] + 1)
+ << USER_ESID_BITS) - 1;
+ vcpu3s->proto_vsid_first = vcpu3s->context_id[0] << USER_ESID_BITS;
+ vcpu3s->proto_vsid_next = vcpu3s->proto_vsid_first;
kvmppc_mmu_hpte_init(vcpu);