diff mbox series

[v3,08/22] KVM: Annotate -EFAULTs from kvm_vcpu_read_guest_page()

Message ID 20230412213510.1220557-9-amoorthy@google.com (mailing list archive)
State New, archived
Headers show
Series Improve scalability of KVM + userfaultfd live migration via annotated memory faults. | expand

Commit Message

Anish Moorthy April 12, 2023, 9:34 p.m. UTC 
Implement KVM_CAP_MEMORY_FAULT_INFO for efaults generated by
kvm_vcpu_read_guest_page().

Signed-off-by: Anish Moorthy <amoorthy@google.com>
---
 virt/kvm/kvm_main.c | 6 +++++-
 1 file changed, 5 insertions(+), 1 deletion(-)
diff mbox series

Patch

diff --git a/virt/kvm/kvm_main.c b/virt/kvm/kvm_main.c
index b29a38af543f0..572adba9ad8ed 100644
--- a/virt/kvm/kvm_main.c
+++ b/virt/kvm/kvm_main.c
@@ -3014,7 +3014,11 @@  int kvm_vcpu_read_guest_page(struct kvm_vcpu *vcpu, gfn_t gfn, void *data,
 {
 	struct kvm_memory_slot *slot = kvm_vcpu_gfn_to_memslot(vcpu, gfn);
 
-	return __kvm_read_guest_page(slot, gfn, data, offset, len);
+	int ret = __kvm_read_guest_page(slot, gfn, data, offset, len);
+
+	if (ret == -EFAULT)
+		kvm_populate_efault_info(vcpu, gfn * PAGE_SIZE + offset, len);
+	return ret;
 }
 EXPORT_SYMBOL_GPL(kvm_vcpu_read_guest_page);