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BAYES_HAM(-3.00)[100.00%]; NEURAL_HAM_LONG(-1.00)[-1.000]; R_DKIM_ALLOW(-0.20)[suse.de:s=susede2_rsa,suse.de:s=susede2_ed25519]; NEURAL_HAM_SHORT(-0.20)[-1.000]; MIME_GOOD(-0.10)[text/plain]; MX_GOOD(-0.01)[]; FUZZY_RATELIMITED(0.00)[rspamd.com]; RCVD_VIA_SMTP_AUTH(0.00)[]; RCVD_TLS_ALL(0.00)[]; ARC_NA(0.00)[]; MIME_TRACE(0.00)[0:+]; MISSING_XM_UA(0.00)[]; TO_DN_SOME(0.00)[]; RECEIVED_SPAMHAUS_BLOCKED_OPENRESOLVER(0.00)[2a07:de40:b281:106:10:150:64:167:received]; MID_RHS_MATCH_FROM(0.00)[]; DKIM_SIGNED(0.00)[suse.de:s=susede2_rsa,suse.de:s=susede2_ed25519]; FROM_EQ_ENVFROM(0.00)[]; FROM_HAS_DN(0.00)[]; RCPT_COUNT_THREE(0.00)[4]; RCVD_COUNT_TWO(0.00)[2]; TO_MATCH_ENVRCPT_ALL(0.00)[]; DBL_BLOCKED_OPENRESOLVER(0.00)[suse.de:dkim,suse.de:mid,suse.de:email,imap1.dmz-prg2.suse.org:rdns,imap1.dmz-prg2.suse.org:helo]; DKIM_TRACE(0.00)[suse.de:+] X-Rspamd-Action: no action X-Rspamd-Queue-Id: AA7D45C4CD X-Rspamd-Server: rspamd1.dmz-prg2.suse.org Received-SPF: pass client-ip=195.135.223.131; 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: 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 Prasad Pandit writes: > On Tue, 13 Jan 2026 at 01:15, Fabiano Rosas wrote: >> There are failures that happen _because_ we cancelled. As I've mentioned >> somewhere else before, the cancellation is not "informed" to all threads >> running migration code, there are some code paths that will simply fail >> as a result of migration_cancel(). We need to allow cancelling to work >> in a possibly stuck thread (such as a blocked recv in the return path), >> but this means we end up calling qemu_file_shutdown indiscriminately. >> In these cases, parts of the code would set FAILED, but that failure is >> a result of cancelling. We've determined that migrate-cancel should >> always lead to CANCELLED and a new migration should always be possible. > > * I see. > >> This is ok, call it an error and done. >> >> > OTOH, if we cancel while processing an error/failure, end user >> > may not see that error because we report - migration was cancelled. >> > >> >> This is interesting, I _think_ it wouldn't be possible to cancel while >> handling an error due to BQL locked, the migrate-cancel wouldn't be >> issued while migration_cleanup is ongoing. However, I don't think we ever >> tested this scenario in particular. Maybe you could try to catch >> something by modifying the /migration/cancel tests, if you're willing. > > * I have made a note of looking at it at a later time. > >> Aside from the QAPI states, there are some internal states we already >> track with separate flags, e.g.: >> >> rp_thread_created, start_postcopy, migration_thread_running, >> switchover_acked, postcopy_package_loaded, fault_thread_quit, >> preempt_thread_status, load_threads_abort. >> >> A bit array could maybe cover all of these and more. >> >> --- >> >> You could send a PoC patch with your idea fixing this FAILING bug? We'd >> need a trigger for migrate, set_caps, etc and the failed event. >> >> If that new patch doesn't get consensus then we merge this one and work >> on a new design as time permits. > > * Considering the above wider coverage area, I think it is best to > first fix the issue at hand and then move to this new change. For now > I'll try to rebase my current patch on your v3: cleanup early > connection code series. Once that is through, I'll take the states > change patch. Hope that's okay. > Ok, go ahead. > Thank you. > --- > - Prasad