From: Jill Donahue Date: Tue, 11 Feb 2025 17:48:05 +0000 (-0700) Subject: USB: gadget: f_midi: f_midi_complete to call queue_work X-Git-Tag: v6.1.130~124 X-Git-Url: http://git.ipfire.org/cgi-bin/gitweb.cgi?a=commitdiff_plain;h=24a942610ee9bafb2692a456ae850c5b2e409b05;p=thirdparty%2Fkernel%2Fstable.git USB: gadget: f_midi: f_midi_complete to call queue_work [ Upstream commit 4ab37fcb42832cdd3e9d5e50653285ca84d6686f ] When using USB MIDI, a lock is attempted to be acquired twice through a re-entrant call to f_midi_transmit, causing a deadlock. Fix it by using queue_work() to schedule the inner f_midi_transmit() via a high priority work queue from the completion handler. Link: https://lore.kernel.org/all/CAArt=LjxU0fUZOj06X+5tkeGT+6RbXzpWg1h4t4Fwa_KGVAX6g@mail.gmail.com/ Fixes: d5daf49b58661 ("USB: gadget: midi: add midi function driver") Cc: stable Signed-off-by: Jill Donahue Link: https://lore.kernel.org/r/20250211174805.1369265-1-jdonahue@fender.com Signed-off-by: Greg Kroah-Hartman Signed-off-by: Sasha Levin --- diff --git a/drivers/usb/gadget/function/f_midi.c b/drivers/usb/gadget/function/f_midi.c index 1d8521103b661..dd1cfeeffb671 100644 --- a/drivers/usb/gadget/function/f_midi.c +++ b/drivers/usb/gadget/function/f_midi.c @@ -282,7 +282,7 @@ f_midi_complete(struct usb_ep *ep, struct usb_request *req) /* Our transmit completed. See if there's more to go. * f_midi_transmit eats req, don't queue it again. */ req->length = 0; - f_midi_transmit(midi); + queue_work(system_highpri_wq, &midi->work); return; } break;