[PATCH v3 16/19] i386/sev: Update CPUID failure handling for in-place conversion

[Michael Roth <michael.roth@amd.com>]

When SNP_LAUNCH_UPDATE fails to update the CPUID page, the CPUID page
data passed in will be re-written with metadata about what CPUID fields
didn't match with what trusted firmware expected. In the case of
in-place conversion, this will have been the same page that was
initially passed to SNP_LAUNCH_UPDATE, and so it will have been put in
a private state prior to making the call.

Make sure to switch it back to shared before accessing it for
error-reporting, otherwise this path will generate a bus error.

While here, sneak in a typo fixup for the error message that gets
printed immediately afterward.

Signed-off-by: Michael Roth <michael.roth@amd.com>
---
 target/i386/sev.c | 8 +++++++-
 1 file changed, 7 insertions(+), 1 deletion(-)

diff --git a/target/i386/sev.c b/target/i386/sev.c
index b28a31b7bf..e15e23c78d 100644
--- a/target/i386/sev.c
+++ b/target/i386/sev.c
@@ -1278,8 +1278,14 @@ sev_snp_launch_update(SevSnpGuestState *sev_snp_guest,
                          ret, fw_error, fw_error_to_str(fw_error));
 
             if (data->type == KVM_SEV_SNP_PAGE_TYPE_CPUID) {
+                if (convert_in_place &&
+                    kvm_set_memory_attributes_shared(data->gpa, data->len)) {
+                    error_report("SEV-SNP: unable to access CPUID page to "
+                                 "check failure reasons");
+                    goto out;
+                }
                 sev_snp_cpuid_report_mismatches(&snp_cpuid_info, data->hva);
-                error_report("SEV-SNP: failed update CPUID page");
+                error_report("SEV-SNP: failed to update CPUID page");
             }
             break;
         }
-- 
2.43.0