[PULL 060/102] i386/sev: add migration blockers only once

Paolo Bonzini posted 102 patches 1 month, 1 week ago
Maintainers: Paolo Bonzini <pbonzini@redhat.com>, Alexander Graf <graf@amazon.com>, Pedro Barbuda <pbarbuda@microsoft.com>, Mohamed Mediouni <mohamed@unpredictable.fr>, Gerd Hoffmann <kraxel@redhat.com>, "Marc-André Lureau" <marcandre.lureau@redhat.com>, Pierrick Bouvier <pierrick.bouvier@linaro.org>, Dorjoy Chowdhury <dorjoychy111@gmail.com>, Eduardo Habkost <eduardo@habkost.net>, Marcel Apfelbaum <marcel.apfelbaum@gmail.com>, "Philippe Mathieu-Daudé" <philmd@linaro.org>, Yanan Wang <wangyanan55@huawei.com>, Zhao Liu <zhao1.liu@intel.com>, "Maciej S. Szmigiero" <maciej.szmigiero@oracle.com>, "Michael S. Tsirkin" <mst@redhat.com>, Richard Henderson <richard.henderson@linaro.org>, Bernhard Beschow <shentey@gmail.com>, Alex Williamson <alex@shazbot.org>, "Cédric Le Goater" <clg@redhat.com>, Cornelia Huck <cohuck@redhat.com>, Peter Xu <peterx@redhat.com>, "Daniel P. Berrangé" <berrange@redhat.com>, John Snow <jsnow@redhat.com>, Cleber Rosa <crosa@redhat.com>, Eric Blake <eblake@redhat.com>, Markus Armbruster <armbru@redhat.com>, Manos Pitsidianakis <manos.pitsidianakis@linaro.org>, "Alex Bennée" <alex.bennee@linaro.org>, Thomas Huth <thuth@redhat.com>, Ani Sinha <anisinha@redhat.com>, Peter Maydell <peter.maydell@linaro.org>, Cameron Esfahani <dirty@apple.com>, Roman Bolshakov <rbolshakov@ddn.com>, Phil Dennis-Jordan <phil@philjordan.eu>, Wei Liu <wei.liu@kernel.org>, Marcelo Tosatti <mtosatti@redhat.com>, David Woodhouse <dwmw2@infradead.org>, Paul Durrant <paul@xen.org>, Magnus Kulke <magnus.kulke@linux.microsoft.com>, Fabiano Rosas <farosas@suse.de>, Laurent Vivier <lvivier@redhat.com>
[PULL 060/102] i386/sev: add migration blockers only once
Posted by Paolo Bonzini 1 month, 1 week ago
From: Ani Sinha <anisinha@redhat.com>

sev_launch_finish() and sev_snp_launch_finish() could be called multiple times
when the confidential guest is being reset/rebooted. The migration
blockers should not be added multiple times, once per invocation. This change
makes sure that the migration blockers are added only one time by adding the
migration blockers to the vm state change handler when the vm transitions to
the running state. Subsequent reboots do not change the state of the vm.

Reviewed-by: Prasad Pandit <pjp@fedoraproject.org>
Signed-off-by: Ani Sinha <anisinha@redhat.com>
Link: https://lore.kernel.org/r/20260225035000.385950-20-anisinha@redhat.com
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
---
 target/i386/sev.c | 20 +++++---------------
 1 file changed, 5 insertions(+), 15 deletions(-)

diff --git a/target/i386/sev.c b/target/i386/sev.c
index 66e38ca32e1..260d8ef88bf 100644
--- a/target/i386/sev.c
+++ b/target/i386/sev.c
@@ -1421,11 +1421,6 @@ sev_launch_finish(SevCommonState *sev_common)
     }
 
     sev_set_guest_state(sev_common, SEV_STATE_RUNNING);
-
-    /* add migration blocker */
-    error_setg(&sev_mig_blocker,
-               "SEV: Migration is not implemented");
-    migrate_add_blocker(&sev_mig_blocker, &error_fatal);
 }
 
 static int snp_launch_update_data(uint64_t gpa, void *hva, size_t len,
@@ -1608,7 +1603,6 @@ static void
 sev_snp_launch_finish(SevCommonState *sev_common)
 {
     int ret, error;
-    Error *local_err = NULL;
     OvmfSevMetadata *metadata;
     SevLaunchUpdateData *data;
     SevSnpGuestState *sev_snp = SEV_SNP_GUEST(sev_common);
@@ -1655,15 +1649,6 @@ sev_snp_launch_finish(SevCommonState *sev_common)
 
     kvm_mark_guest_state_protected();
     sev_set_guest_state(sev_common, SEV_STATE_RUNNING);
-
-    /* add migration blocker */
-    error_setg(&sev_mig_blocker,
-               "SEV-SNP: Migration is not implemented");
-    ret = migrate_add_blocker(&sev_mig_blocker, &local_err);
-    if (local_err) {
-        error_report_err(local_err);
-        exit(1);
-    }
 }
 
 
@@ -1676,6 +1661,11 @@ sev_vm_state_change(void *opaque, bool running, RunState state)
     if (running) {
         if (!sev_check_state(sev_common, SEV_STATE_RUNNING)) {
             klass->launch_finish(sev_common);
+
+            /* add migration blocker */
+            error_setg(&sev_mig_blocker,
+                       "SEV: Migration is not implemented");
+            migrate_add_blocker(&sev_mig_blocker, &error_fatal);
         }
     }
 }
-- 
2.53.0