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envelope-from=peterx@redhat.com; helo=us-smtp-delivery-124.mimecast.com X-Spam_score_int: -20 X-Spam_score: -2.1 X-Spam_bar: -- X-Spam_report: (-2.1 / 5.0 requ) BAYES_00=-1.9, DKIMWL_WL_HIGH=-0.001, DKIM_SIGNED=0.1, DKIM_VALID=-0.1, DKIM_VALID_AU=-0.1, DKIM_VALID_EF=-0.1, RCVD_IN_DNSWL_NONE=-0.0001, RCVD_IN_MSPIKE_H2=0.001, RCVD_IN_VALIDITY_CERTIFIED_BLOCKED=0.001, RCVD_IN_VALIDITY_RPBL_BLOCKED=0.001, SPF_HELO_PASS=-0.001, SPF_PASS=-0.001 autolearn=ham autolearn_force=no X-Spam_action: no action X-BeenThere: qemu-devel@nongnu.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: qemu development List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Errors-To: qemu-devel-bounces+qemu-devel=archiver.kernel.org@nongnu.org Sender: qemu-devel-bounces+qemu-devel=archiver.kernel.org@nongnu.org On Sun, Jan 25, 2026 at 09:40:10PM +0100, Lukas Straub wrote: > With colo we load device vmstate during each checkpoint, on top of > a vm that was already running. Some devices expect a reset before > loading vmstate on such a previously running vm. > > This fixes a crash when using COLO with Q35 machine. > > Signed-off-by: Lukas Straub Yes makes sense, maybe you can add some comments into the code too since this was overlooked before, Reviewed-by: Peter Xu Have you tried to measure how many overheads will this introduce to loading each snapshot? > --- > migration/colo.c | 1 + > 1 file changed, 1 insertion(+) > > diff --git a/migration/colo.c b/migration/colo.c > index db783f6fa77500386d923dd97e522883027e71d8..627b3706687036554eda3909b4194116a7640493 100644 > --- a/migration/colo.c > +++ b/migration/colo.c > @@ -727,6 +727,7 @@ static void colo_incoming_process_checkpoint(MigrationIncomingState *mis, > > bql_lock(); > vmstate_loading = true; > + qemu_system_reset(SHUTDOWN_CAUSE_SNAPSHOT_LOAD); > colo_flush_ram_cache(); > ret = qemu_load_device_state(fb, errp); > if (ret < 0) { > > -- > 2.39.5 > -- Peter Xu