FAILED: patch "[PATCH] USB: gadget: f_midi: f_midi_complete to call queue_work" failed to apply to 6.6-stable tree

[<gregkh@linuxfoundation.org>]

The patch below does not apply to the 6.6-stable tree.
If someone wants it applied there, or to any other stable or longterm
tree, then please email the backport, including the original git commit
id to <stable@vger.kernel.org>.

To reproduce the conflict and resubmit, you may use the following commands:

git fetch https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git/ linux-6.6.y
git checkout FETCH_HEAD
git cherry-pick -x 4ab37fcb42832cdd3e9d5e50653285ca84d6686f
# <resolve conflicts, build, test, etc.>
git commit -s
git send-email --to '<stable@vger.kernel.org>' --in-reply-to '2025021830-phantom-negligent-416a@gregkh' --subject-prefix 'PATCH 6.6.y' HEAD^..

Possible dependencies:



thanks,

greg k-h

------------------ original commit in Linus's tree ------------------

From 4ab37fcb42832cdd3e9d5e50653285ca84d6686f Mon Sep 17 00:00:00 2001
From: Jill Donahue <jilliandonahue58@gmail.com>
Date: Tue, 11 Feb 2025 10:48:05 -0700
Subject: [PATCH] USB: gadget: f_midi: f_midi_complete to call queue_work

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 <stable@kernel.org>
Signed-off-by: Jill Donahue <jilliandonahue58@gmail.com>
Link: https://lore.kernel.org/r/20250211174805.1369265-1-jdonahue@fender.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

diff --git a/drivers/usb/gadget/function/f_midi.c b/drivers/usb/gadget/function/f_midi.c
index 47260d65066a..da82598fcef8 100644
--- a/drivers/usb/gadget/function/f_midi.c
+++ b/drivers/usb/gadget/function/f_midi.c
@@ -283,7 +283,7 @@ 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;