diff mbox series

[RFCv2,10/16] KVM: x86: Use GUP for page walk instead of __get_user()

Message ID 20201020061859.18385-11-kirill.shutemov@linux.intel.com (mailing list archive)
State New, archived
Headers show
Series KVM protected memory extension | expand

Commit Message

Kirill A. Shutemov Oct. 20, 2020, 6:18 a.m. UTC 
The user mapping doesn't have the page mapping for protected memory.

Signed-off-by: Kirill A. Shutemov <kirill.shutemov@linux.intel.com>
---
 arch/x86/kvm/mmu/paging_tmpl.h | 10 ++++++++--
 1 file changed, 8 insertions(+), 2 deletions(-)
diff mbox series

Patch

diff --git a/arch/x86/kvm/mmu/paging_tmpl.h b/arch/x86/kvm/mmu/paging_tmpl.h
index 4dd6b1e5b8cf..258a6361b9b2 100644
--- a/arch/x86/kvm/mmu/paging_tmpl.h
+++ b/arch/x86/kvm/mmu/paging_tmpl.h
@@ -397,8 +397,14 @@  static int FNAME(walk_addr_generic)(struct guest_walker *walker,
 			goto error;
 
 		ptep_user = (pt_element_t __user *)((void *)host_addr + offset);
-		if (unlikely(__get_user(pte, ptep_user)))
-			goto error;
+		if (vcpu->kvm->mem_protected) {
+			if (copy_from_guest(&pte, host_addr + offset,
+					    sizeof(pte), true))
+				goto error;
+		} else {
+			if (unlikely(__get_user(pte, ptep_user)))
+				goto error;
+		}
 		walker->ptep_user[walker->level - 1] = ptep_user;
 
 		trace_kvm_mmu_paging_element(pte, walker->level);