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envelope-from=farosas@suse.de; helo=smtp-out2.suse.de X-Spam_score_int: -43 X-Spam_score: -4.4 X-Spam_bar: ---- X-Spam_report: (-4.4 / 5.0 requ) BAYES_00=-1.9, DKIM_SIGNED=0.1, DKIM_VALID=-0.1, DKIM_VALID_AU=-0.1, DKIM_VALID_EF=-0.1, RCVD_IN_DNSWL_MED=-2.3, RCVD_IN_VALIDITY_RPBL_BLOCKED=0.001, RCVD_IN_VALIDITY_SAFE_BLOCKED=0.001, SPF_HELO_NONE=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: 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 Peter Xu writes: > On Thu, Aug 07, 2025 at 01:49:10PM +0200, Juraj Marcin wrote: >> From: Juraj Marcin >> >> Depending on where an error during postcopy_start() happens, the state >> can be either "active", "device" or "cancelling", but never >> "postcopy-active". Migration state is transitioned to "postcopy-active" >> only just before a successful return from the function. >> >> Accept any state except "cancelling" when transitioning to "failed" >> state. >> >> Signed-off-by: Juraj Marcin >> --- >> migration/migration.c | 5 +++-- >> 1 file changed, 3 insertions(+), 2 deletions(-) >> >> diff --git a/migration/migration.c b/migration/migration.c >> index 10c216d25d..e5ce2940d5 100644 >> --- a/migration/migration.c >> +++ b/migration/migration.c >> @@ -2872,8 +2872,9 @@ static int postcopy_start(MigrationState *ms, Error **errp) >> fail_closefb: >> qemu_fclose(fb); >> fail: >> - migrate_set_state(&ms->state, MIGRATION_STATUS_POSTCOPY_ACTIVE, >> - MIGRATION_STATUS_FAILED); >> + if ( ms->state != MIGRATION_STATUS_CANCELLING) { >> + migrate_set_state(&ms->state, ms->state, MIGRATION_STATUS_FAILED); >> + } > > Hmm, this might have been overlooked from my commit 48814111366b. Maybe > worth a Fixes and copy stable? > > For example, I would expect the old code (prior of 48814111366b) still be > able to fail postcopy and resume src QEMU if qemu_savevm_send_packaged() > failed. Now, looks like it'll be stuck at "device" state.. > > The other thing is it also looks like a common pattern to set FAILED > meanwhile not messing with a CANCELLING stage. It's not easy to always > remember this, so maybe we should consider having a helper function? > > migrate_set_failure(MigrationState *, Error *err); > We didn't do it back then because at there would be some logical conflict with this series: https://lore.kernel.org/r/20250110100707.4805-1-shivam.kumar1@nutanix.com But I don't remember the details. If it works this time I'm all for it. > Which could set err with migrate_set_error() (likely we could also > error_report() the error), and update FAILED iff it's not CANCELLING. > > I saw three of such occurances that such helper may apply, but worth double > check: > > postcopy_start[2725] if (ms->state != MIGRATION_STATUS_CANCELLING) { > migration_completion[3069] if (s->state != MIGRATION_STATUS_CANCELLING) { > igration_connect[4064] if (s->state != MIGRATION_STATUS_CANCELLING) { > > If the cleanup looks worthwhile, and if the Fixes apply, we could have the > cleanup patch on top of the fixes patch so patch 1 is easier to backport. > > Thanks, > >> migration_block_activate(NULL); >> migration_call_notifiers(ms, MIG_EVENT_PRECOPY_FAILED, NULL); >> bql_unlock(); >> -- >> 2.50.1 >>