Implement KVM_CAP_MEMORY_FAULT_INFO for uaccess failures in
kvm_vcpu_write_guest_page()
Signed-off-by: Anish Moorthy <amoorthy@xxxxxxxxxx>
---
virt/kvm/kvm_main.c | 17 ++++++++++++-----
1 file changed, 12 insertions(+), 5 deletions(-)
diff --git a/virt/kvm/kvm_main.c b/virt/kvm/kvm_main.c
index d9c0fa7c907f..ea27a8178f1a 100644
--- a/virt/kvm/kvm_main.c
+++ b/virt/kvm/kvm_main.c
@@ -3090,8 +3090,10 @@ EXPORT_SYMBOL_GPL(kvm_vcpu_read_guest_atomic);
/*
* Copy 'len' bytes from 'data' into guest memory at '(gfn * PAGE_SIZE) + offset'
+ * If 'vcpu' is non-null, then may fill its run struct for a
+ * KVM_EXIT_MEMORY_FAULT on uaccess failure.
*/
-static int __kvm_write_guest_page(struct kvm *kvm,
+static int __kvm_write_guest_page(struct kvm *kvm, struct kvm_vcpu *vcpu,
struct kvm_memory_slot *memslot, gfn_t gfn,
const void *data, int offset, int len)
{
@@ -3102,8 +3104,13 @@ static int __kvm_write_guest_page(struct kvm *kvm,
if (kvm_is_error_hva(addr))
return -EFAULT;
r = __copy_to_user((void __user *)addr + offset, data, len);
- if (r)
+ if (r) {
+ if (vcpu)
+ kvm_populate_efault_info(vcpu, gfn * PAGE_SIZE + offset,
+ len,
+ KVM_MEMORY_FAULT_FLAG_WRITE);
return -EFAULT;
+ }
mark_page_dirty_in_slot(kvm, memslot, gfn);
return 0;
}
@@ -3113,7 +3120,7 @@ int kvm_write_guest_page(struct kvm *kvm, gfn_t gfn,
{
struct kvm_memory_slot *slot = gfn_to_memslot(kvm, gfn);
- return __kvm_write_guest_page(kvm, slot, gfn, data, offset, len);
+ return __kvm_write_guest_page(kvm, NULL, slot, gfn, data, offset, len);
}
EXPORT_SYMBOL_GPL(kvm_write_guest_page);
@@ -3121,8 +3128,8 @@ int kvm_vcpu_write_guest_page(struct kvm_vcpu *vcpu, gfn_t gfn,
const void *data, int offset, int len)
{
struct kvm_memory_slot *slot = kvm_vcpu_gfn_to_memslot(vcpu, gfn);
-
- return __kvm_write_guest_page(vcpu->kvm, slot, gfn, data, offset, len);
+ return __kvm_write_guest_page(vcpu->kvm, vcpu, slot, gfn, data,
+ offset, len);
}
EXPORT_SYMBOL_GPL(kvm_vcpu_write_guest_page);
--
2.41.0.rc0.172.g3f132b7071-goog
