summaryrefslogtreecommitdiffstats
path: root/virt
diff options
context:
space:
mode:
authorPaolo Bonzini <pbonzini@redhat.com>2020-04-17 12:21:06 -0400
committerPaolo Bonzini <pbonzini@redhat.com>2020-04-21 09:13:13 -0400
commite72436bc3a5206f95bb384e741154166ddb3202e (patch)
tree3bbd58436dcb3900f1f0c276e497b8381d0b169b /virt
parent997b7e98990cd44243651827e4efa366d9885907 (diff)
downloadlinux-e72436bc3a5206f95bb384e741154166ddb3202e.tar.bz2
KVM: SVM: avoid infinite loop on NPF from bad address
When a nested page fault is taken from an address that does not have a memslot associated to it, kvm_mmu_do_page_fault returns RET_PF_EMULATE (via mmu_set_spte) and kvm_mmu_page_fault then invokes svm_need_emulation_on_page_fault. The default answer there is to return false, but in this case this just causes the page fault to be retried ad libitum. Since this is not a fast path, and the only other case where it is taken is an erratum, just stick a kvm_vcpu_gfn_to_memslot check in there to detect the common case where the erratum is not happening. This fixes an infinite loop in the new set_memory_region_test. Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Diffstat (limited to 'virt')
-rw-r--r--virt/kvm/kvm_main.c1
1 files changed, 1 insertions, 0 deletions
diff --git a/virt/kvm/kvm_main.c b/virt/kvm/kvm_main.c
index e2f60e313c87..e7436d054305 100644
--- a/virt/kvm/kvm_main.c
+++ b/virt/kvm/kvm_main.c
@@ -1602,6 +1602,7 @@ struct kvm_memory_slot *kvm_vcpu_gfn_to_memslot(struct kvm_vcpu *vcpu, gfn_t gfn
{
return __gfn_to_memslot(kvm_vcpu_memslots(vcpu), gfn);
}
+EXPORT_SYMBOL_GPL(kvm_vcpu_gfn_to_memslot);
bool kvm_is_visible_gfn(struct kvm *kvm, gfn_t gfn)
{