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charset=ISO-8859-1 Content-Transfer-Encoding: 8bit X-Spamd-Result: default: False [-3.51 / 50.00]; BAYES_HAM(-3.00)[99.99%]; MID_CONTAINS_FROM(1.00)[]; 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)[]; MIME_TRACE(0.00)[0:+]; SPAMHAUS_XBL(0.00)[2a07:de40:b281:104:10:150:64:97:from]; DKIM_SIGNED(0.00)[suse.de:s=susede2_rsa,suse.de:s=susede2_ed25519]; ARC_NA(0.00)[]; FREEMAIL_TO(0.00)[gmail.com]; TO_DN_SOME(0.00)[]; FUZZY_RATELIMITED(0.00)[rspamd.com]; RBL_SPAMHAUS_BLOCKED_OPENRESOLVER(0.00)[2a07:de40:b281:104:10:150:64:97:from]; FREEMAIL_ENVRCPT(0.00)[gmail.com]; RCPT_COUNT_FIVE(0.00)[6]; RCVD_COUNT_TWO(0.00)[2]; FROM_EQ_ENVFROM(0.00)[]; FROM_HAS_DN(0.00)[]; TO_MATCH_ENVRCPT_ALL(0.00)[]; RECEIVED_SPAMHAUS_BLOCKED_OPENRESOLVER(0.00)[2a07:de40:b281:106:10:150:64:167:received]; DKIM_TRACE(0.00)[suse.de:+]; RCVD_VIA_SMTP_AUTH(0.00)[]; RCVD_TLS_ALL(0.00)[]; DBL_BLOCKED_OPENRESOLVER(0.00)[imap1.dmz-prg2.suse.org:helo,imap1.dmz-prg2.suse.org:rdns,suse.de:dkim,suse.de:mid] X-Rspamd-Action: no action X-Spam-Flag: NO X-Spam-Score: -3.51 X-Spam-Level: X-Rspamd-Server: rspamd1.dmz-prg2.suse.org X-Rspamd-Queue-Id: D28D24D338 On Mon, 23 Mar 2026 14:46:24 +0100, Cássio Gabriel wrote: > > snd_usbmidi_standard_output() iterates output ports in ascending order > and drains each active port until the URB is full. On interfaces where > multiple USB-MIDI cables share one endpoint, sustained traffic on a > lower-numbered port can consume every refill before higher-numbered > ports are even examined. > > That behavior dates back to the original implementation and still > applies with the current multi-URB output path. snd_usbmidi_do_output() > can refill several idle URBs in one pass, but each refill restarts the > scan at port 0, so a busy lower-numbered port can keep higher-numbered > ports from making progress at all. > > Use ep->current_port as the starting point of the scan and advance it > after each URB fill. This keeps the existing packet formatting and > per-port state handling intact while preventing persistent starvation of > higher-numbered ports. > > Signed-off-by: Cássio Gabriel Looks like a nice logical improvement. Applied to for-next branch now. Thanks. Takashi