tree ef9188945fce0de6f56c61f374ef8b5d3074aaac
parent 49b110491153d954646282c84f81976f83b8041b
author Steve Rutherford <srutherford@google.com> 1692916651 -0700
committer COS Cherry Picker <cloud-image-release@prod.google.com> 1694120791 -0700

x86/sev: Make enc_dec_hypercall() accept a size instead of npages

enc_dec_hypercall() accepted a page count instead of a size, which
forced its callers to round up. As a result, non-page aligned
vaddrs caused pages to be spuriously marked as decrypted via the
encryption status hypercall, which in turn caused consistent
corruption of pages during live migration. Live migration requires
accurate encryption status information to avoid migrating pages
from the wrong perspective.

BUG=b/297544590
TEST=presubmit
RELEASE_NOTE=None

cos-patch: bug
Fixes: 064ce6c550a0 ("mm: x86: Invoke hypercall when page encryption status is changed")
Signed-off-by: Steve Rutherford <srutherford@google.com>
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Reviewed-by: Tom Lendacky <thomas.lendacky@amd.com>
Reviewed-by: Pankaj Gupta <pankaj.gupta@amd.com>
Tested-by: Ben Hillier <bhillier@google.com>
Cc: stable@vger.kernel.org
Link: https://lore.kernel.org/r/20230824223731.2055016-1-srutherford@google.com
Change-Id: I09c552b5ce1a030030d7585cbff29a309b5e680a
Reviewed-on: https://cos-review.googlesource.com/c/third_party/kernel/+/56568
Reviewed-by: Arnav Kansal <rnv@google.com>
Tested-by: Cusky Presubmit Bot <presubmit@cos-infra-prod.iam.gserviceaccount.com>
Main-Branch-Verified: Cusky Presubmit Bot <presubmit@cos-infra-prod.iam.gserviceaccount.com>