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GET /api/patches/2026277/?format=api
HTTP 200 OK
Allow: GET, PUT, PATCH, HEAD, OPTIONS
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{
    "id": 2026277,
    "url": "http://patchwork.ozlabs.org/api/patches/2026277/?format=api",
    "web_url": "http://patchwork.ozlabs.org/project/qemu-devel/patch/20241220104220.2007786-3-npiggin@gmail.com/",
    "project": {
        "id": 14,
        "url": "http://patchwork.ozlabs.org/api/projects/14/?format=api",
        "name": "QEMU Development",
        "link_name": "qemu-devel",
        "list_id": "qemu-devel.nongnu.org",
        "list_email": "qemu-devel@nongnu.org",
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        "scm_url": "",
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        "list_archive_url_format": "",
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    },
    "msgid": "<20241220104220.2007786-3-npiggin@gmail.com>",
    "list_archive_url": null,
    "date": "2024-12-20T10:42:04",
    "name": "[02/17] replay: Fix migration replay_mutex locking",
    "commit_ref": null,
    "pull_url": null,
    "state": "new",
    "archived": false,
    "hash": "e02a63228832c67ed58e2388df0c8f9b7142af1d",
    "submitter": {
        "id": 69518,
        "url": "http://patchwork.ozlabs.org/api/people/69518/?format=api",
        "name": "Nicholas Piggin",
        "email": "npiggin@gmail.com"
    },
    "delegate": null,
    "mbox": "http://patchwork.ozlabs.org/project/qemu-devel/patch/20241220104220.2007786-3-npiggin@gmail.com/mbox/",
    "series": [
        {
            "id": 437728,
            "url": "http://patchwork.ozlabs.org/api/series/437728/?format=api",
            "web_url": "http://patchwork.ozlabs.org/project/qemu-devel/list/?series=437728",
            "date": "2024-12-20T10:42:02",
            "name": "replay: Fixes and avocado test updates",
            "version": 1,
            "mbox": "http://patchwork.ozlabs.org/series/437728/mbox/"
        }
    ],
    "comments": "http://patchwork.ozlabs.org/api/patches/2026277/comments/",
    "check": "pending",
    "checks": "http://patchwork.ozlabs.org/api/patches/2026277/checks/",
    "tags": {},
    "related": [],
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        "From": "Nicholas Piggin <npiggin@gmail.com>",
        "To": "qemu-devel@nongnu.org",
        "Cc": "Nicholas Piggin <npiggin@gmail.com>, qemu-block@nongnu.org, =?utf-8?q?Al?=\n\t=?utf-8?q?ex_Benn=C3=A9e?= <alex.bennee@linaro.org>,\n Kevin Wolf <kwolf@redhat.com>, Hanna Reitz <hreitz@redhat.com>,\n Pavel Dovgalyuk <pavel.dovgaluk@ispras.ru>,\n Paolo Bonzini <pbonzini@redhat.com>, Stefan Hajnoczi <stefanha@redhat.com>,\n Fam Zheng <fam@euphon.net>, Ronnie Sahlberg <ronniesahlberg@gmail.com>,\n John Snow <jsnow@redhat.com>, \"Michael S. Tsirkin\" <mst@redhat.com>,\n Jason Wang <jasowang@redhat.com>,\n Vladimir Sementsov-Ogievskiy <vsementsov@yandex-team.ru>,\n Peter Xu <peterx@redhat.com>, Fabiano Rosas <farosas@suse.de>,\n \"Dr. David Alan Gilbert\" <dave@treblig.org>,\n Markus Armbruster <armbru@redhat.com>, Michael Roth <michael.roth@amd.com>,\n Wainer dos Santos Moschetta <wainersm@redhat.com>",
        "Subject": "[PATCH 02/17] replay: Fix migration replay_mutex locking",
        "Date": "Fri, 20 Dec 2024 20:42:04 +1000",
        "Message-ID": "<20241220104220.2007786-3-npiggin@gmail.com>",
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        "References": "<20241220104220.2007786-1-npiggin@gmail.com>",
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    },
    "content": "Migration causes a number of events that need to go in the replay\ntrace, such as vm state transitions. The replay_mutex lock needs to\nbe held for these.\n\nThe simplest approach seems to be just take it up-front when taking\nthe bql.\n\nSigned-off-by: Nicholas Piggin <npiggin@gmail.com>\n---\n migration/migration.c | 9 +++++++++\n 1 file changed, 9 insertions(+)",
    "diff": "diff --git a/migration/migration.c b/migration/migration.c\nindex 2eb9e50a263..277fca954c1 100644\n--- a/migration/migration.c\n+++ b/migration/migration.c\n@@ -24,6 +24,7 @@\n #include \"socket.h\"\n #include \"sysemu/runstate.h\"\n #include \"sysemu/sysemu.h\"\n+#include \"sysemu/replay.h\"\n #include \"sysemu/cpu-throttle.h\"\n #include \"rdma.h\"\n #include \"ram.h\"\n@@ -2518,6 +2519,7 @@ static int postcopy_start(MigrationState *ms, Error **errp)\n     }\n \n     trace_postcopy_start();\n+    replay_mutex_lock();\n     bql_lock();\n     trace_postcopy_start_set_run();\n \n@@ -2629,6 +2631,7 @@ static int postcopy_start(MigrationState *ms, Error **errp)\n     migration_downtime_end(ms);\n \n     bql_unlock();\n+    replay_mutex_unlock();\n \n     if (migrate_postcopy_ram()) {\n         /*\n@@ -2670,6 +2673,7 @@ fail:\n     }\n     migration_call_notifiers(ms, MIG_EVENT_PRECOPY_FAILED, NULL);\n     bql_unlock();\n+    replay_mutex_unlock();\n     return -1;\n }\n \n@@ -2721,6 +2725,7 @@ static int migration_completion_precopy(MigrationState *s,\n {\n     int ret;\n \n+    replay_mutex_lock();\n     bql_lock();\n \n     if (!migrate_mode_is_cpr(s)) {\n@@ -2746,6 +2751,7 @@ static int migration_completion_precopy(MigrationState *s,\n                                              s->block_inactive);\n out_unlock:\n     bql_unlock();\n+    replay_mutex_unlock();\n     return ret;\n }\n \n@@ -3633,6 +3639,7 @@ static void *bg_migration_thread(void *opaque)\n \n     trace_migration_thread_setup_complete();\n \n+    replay_mutex_lock();\n     bql_lock();\n \n     if (migration_stop_vm(s, RUN_STATE_PAUSED)) {\n@@ -3666,6 +3673,7 @@ static void *bg_migration_thread(void *opaque)\n      */\n     migration_bh_schedule(bg_migration_vm_start_bh, s);\n     bql_unlock();\n+    replay_mutex_unlock();\n \n     while (migration_is_active()) {\n         MigIterateState iter_state = bg_migration_iteration_run(s);\n@@ -3695,6 +3703,7 @@ fail:\n         migrate_set_state(&s->state, MIGRATION_STATUS_ACTIVE,\n                 MIGRATION_STATUS_FAILED);\n         bql_unlock();\n+        replay_mutex_unlock();\n     }\n \n fail_setup:\n",
    "prefixes": [
        "02/17"
    ]
}