diff options
authorSuraj Jitindar Singh <>2019-06-20 11:46:49 +1000
committerMichael Ellerman <>2019-06-20 22:11:25 +1000
commit50087112592016a3fc10b394a55f1f1a1bde6908 (patch)
parent9739ab7eda459f0669ec9807e0d9be5020bab88c (diff)
KVM: PPC: Book3S HV: Invalidate ERAT when flushing guest TLB entries
When a guest vcpu moves from one physical thread to another it is necessary for the host to perform a tlb flush on the previous core if another vcpu from the same guest is going to run there. This is because the guest may use the local form of the tlb invalidation instruction meaning stale tlb entries would persist where it previously ran. This is handled on guest entry in kvmppc_check_need_tlb_flush() which calls flush_guest_tlb() to perform the tlb flush. Previously the generic radix__local_flush_tlb_lpid_guest() function was used, however the functionality was reimplemented in flush_guest_tlb() to avoid the trace_tlbie() call as the flushing may be done in real mode. The reimplementation in flush_guest_tlb() was missing an erat invalidation after flushing the tlb. This lead to observable memory corruption in the guest due to the caching of stale translations. Fix this by adding the erat invalidation. Fixes: 70ea13f6e609 ("KVM: PPC: Book3S HV: Flush TLB on secondary radix threads") Signed-off-by: Suraj Jitindar Singh <> Signed-off-by: Michael Ellerman <>
1 files changed, 1 insertions, 0 deletions
diff --git a/arch/powerpc/kvm/book3s_hv_builtin.c b/arch/powerpc/kvm/book3s_hv_builtin.c
index 6035d24f1d1d..a46286f73eec 100644
--- a/arch/powerpc/kvm/book3s_hv_builtin.c
+++ b/arch/powerpc/kvm/book3s_hv_builtin.c
@@ -833,6 +833,7 @@ static void flush_guest_tlb(struct kvm *kvm)
asm volatile("ptesync": : :"memory");
+ asm volatile(PPC_INVALIDATE_ERAT : : :"memory");
void kvmppc_check_need_tlb_flush(struct kvm *kvm, int pcpu,