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* FAILED: patch "[PATCH] ALSA: usb-audio: Complete cleanup after system-resume errors" failed to apply to 5.10-stable tree
@ 2026-08-31 13:20 gregkh
  2026-09-01 20:40 ` [PATCH 5.10.y 1/5] ALSA: usb-audio: Carve out connector value checking into a helper Sasha Levin
  0 siblings, 1 reply; 6+ messages in thread
From: gregkh @ 2026-08-31 13:20 UTC (permalink / raw)
  To: mrwillporter, stable, tiwai; +Cc: stable


The patch below does not apply to the 5.10-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-5.10.y
git checkout FETCH_HEAD
git cherry-pick -x 1739a976312e110c93a8dee66a1cdf893a1b187e
# <resolve conflicts, build, test, etc.>
git commit -s
git send-email --to '<stable@vger.kernel.org>' --in-reply-to '2026083119-straddle-squeegee-5817@gregkh' --subject-prefix 'PATCH 5.10.y' 'HEAD^..'

Possible dependencies:



thanks,

greg k-h

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

From 1739a976312e110c93a8dee66a1cdf893a1b187e Mon Sep 17 00:00:00 2001
From: Will Porter <mrwillporter@gmail.com>
Date: Mon, 24 Aug 2026 17:57:57 -0500
Subject: [PATCH] ALSA: usb-audio: Complete cleanup after system-resume errors

A failed system resume can leave the card unusable until reboot.
usb_audio_resume() jumps to err_out when snd_usb_pcm_resume() or
snd_usb_mixer_resume() fails. The error path skips the out: block, which
restores D0 and decrements chip->num_suspended_intf.

The card stays in SNDRV_CTL_POWER_D3hot, so later control access blocks in
snd_power_ref_and_wait(). USB core logs an interface resume callback error.
It does not retry that callback, so a later callback cannot complete the
skipped cleanup.

usb_audio_suspend() increments num_suspended_intf before returning success.
A system-resume callback must consume the system-suspend count even if a
component resume fails. Otherwise, the stranded count skews later suspend
and resume cycles.

Do not apply this cleanup to runtime-resume errors. Runtime PM can retry
-EAGAIN or -EBUSY without another suspend callback. The count must continue
to describe that suspended interface. Other runtime-resume errors latch
runtime_error in the PM core and do not cause an immediate callback retry.

Both parts of the system-resume error path are longstanding. Commit
88a8516a2128a ("ALSA: usbaudio: implement USB autosuspend") introduced
err_out past the D0 restore. Commit 862b2509d157c ("ALSA: usb-audio: Fix
inconsistent card PM state after resume") later moved
num_suspended_intf-- into the out: block. The error path now skips both
operations.

No third-party code is needed to reach the error path.
snd_usb_mixer_resume() ends in snd_usb_mixer_activate(), which returns the
result of usb_submit_urb() for devices that have a mixer status URB. Its
mixer->private_resume hook can also fail through scarlett2_init_notify().
snd_usb_pcm_resume() issues a SET_CUR request to a UAC3 power domain. It
can return -EPIPE or -EIO when the device stalls the request.

Route a component error through out: only when system_suspend is nonzero.
Continue to return runtime-resume errors through err_out. Later component
resume stages remain skipped. The original error still reaches USB core.
A later transfer can fail if the device did not recover.

I reproduced the system-resume failure on an Audient iD14 MkI with an
out-of-tree diagnostic mixer resume hook. An injected -EIO on the unpatched
core left control readers in uninterruptible sleep in
snd_power_ref_and_wait() until a reboot. With this patch, the same failure
restored control access. A second system suspend and resume also succeeded
after I disabled fault injection.

Assisted-by: Claude:claude-opus-5
Assisted-by: Antigravity:gemini-3.1-pro-high
Assisted-by: Codex:gpt-5.6-sol
Fixes: 88a8516a2128a ("ALSA: usbaudio: implement USB autosuspend")
Fixes: 862b2509d157c ("ALSA: usb-audio: Fix inconsistent card PM state after resume")
Cc: <stable@vger.kernel.org>
Signed-off-by: Will Porter <mrwillporter@gmail.com>
Link: https://patch.msgid.link/20260824225757.26749-1-mrwillporter@gmail.com
Signed-off-by: Takashi Iwai <tiwai@suse.de>

diff --git a/sound/usb/card.c b/sound/usb/card.c
index 24112e491779..9307da95efbe 100644
--- a/sound/usb/card.c
+++ b/sound/usb/card.c
@@ -1282,8 +1282,11 @@ static int usb_audio_resume(struct usb_interface *intf)
 
 	list_for_each_entry(as, &chip->pcm_list, list) {
 		err = snd_usb_pcm_resume(as);
-		if (err < 0)
-			goto err_out;
+		if (err < 0) {
+			if (!chip->system_suspend)
+				goto err_out;
+			goto out;
+		}
 	}
 
 	/*
@@ -1292,8 +1295,11 @@ static int usb_audio_resume(struct usb_interface *intf)
 	 */
 	list_for_each_entry(mixer, &chip->mixer_list, list) {
 		err = snd_usb_mixer_resume(mixer);
-		if (err < 0)
-			goto err_out;
+		if (err < 0) {
+			if (!chip->system_suspend)
+				goto err_out;
+			goto out;
+		}
 	}
 
 	list_for_each(p, &chip->midi_list) {


^ permalink raw reply related	[flat|nested] 6+ messages in thread

end of thread, other threads:[~2026-09-01 20:40 UTC | newest]

Thread overview: 6+ messages (download: mbox.gz follow: Atom feed
-- links below jump to the message on this page --
2026-08-31 13:20 FAILED: patch "[PATCH] ALSA: usb-audio: Complete cleanup after system-resume errors" failed to apply to 5.10-stable tree gregkh
2026-09-01 20:40 ` [PATCH 5.10.y 1/5] ALSA: usb-audio: Carve out connector value checking into a helper Sasha Levin
2026-09-01 20:40   ` [PATCH 5.10.y 2/5] ALSA: usb-audio: Check connector value on resume Sasha Levin
2026-09-01 20:40   ` [PATCH 5.10.y 3/5] ALSA: usb-audio: Avoid unnecessary or invalid connector selection at resume Sasha Levin
2026-09-01 20:40   ` [PATCH 5.10.y 4/5] ALSA: usb-audio: Unify mixer resume and reset_resume procedure Sasha Levin
2026-09-01 20:40   ` [PATCH 5.10.y 5/5] ALSA: usb-audio: Complete cleanup after system-resume errors Sasha Levin

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