From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from smtp.kernel.org (aws-us-west-2-korg-mail-alma10-1.taild15c8.ts.net [100.103.45.18]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 6E2ED494804; Mon, 31 Aug 2026 14:06:07 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=100.103.45.18 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1788185168; cv=none; b=WL7ZkkSX5ye6UON/LHrQyS4KT5Ei9/zi4wkOZhASl/v1FC/ECpIGjy3oeBkg5SUl2NhW0WAVy9ibYuRBNVmsPZvZsMloNrJg7Ty5KbwGL+j7gTFuA2PIgpnM8o6ahjccQCjT2RLJg+9l64SG7mWOdZ53lKiLuhglNZ8E116NziY= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1788185168; c=relaxed/simple; bh=Zoeza8n6QCXH2vxpwBeNY5He52xljLiYVZEmEJQfSBY=; h=From:To:Cc:Subject:Date:Message-ID:In-Reply-To:References: MIME-Version; b=XbXrwOXsd9gpGpOgI8vCbTAWgkPjXisTd+7p1byWcmmknMxTzTepSwPjhsIkIB8KejHH+tpWqz3CVd99Au4SdeuonihENTLo957DwvntJlYKFS7N4gdycRUwS7zGKyclWxT8An+CYFSPFA5C4WSVEB2fEE3RVxxMaJ2M46ViRXI= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linuxfoundation.org header.i=@linuxfoundation.org header.b=N/idyFkU; arc=none smtp.client-ip=100.103.45.18 Authentication-Results: smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linuxfoundation.org header.i=@linuxfoundation.org header.b="N/idyFkU" Received: by smtp.kernel.org (Postfix) with ESMTPSA id B42E61F000E9; Mon, 31 Aug 2026 14:06:06 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=linuxfoundation.org; s=korg; t=1788185167; bh=m7hBJ2VhISshGbYNtTSVV5Terds/O8p5XnteERP5ri0=; h=From:To:Cc:Subject:Date:In-Reply-To:References; b=N/idyFkUdEbD+BfG/tSrVvl1E+9yXtthZstj8QNiS6EK+YGdTOc7RLJpG1QT7Eqcp c1VT5aEmJasdOcyUOOuQmlQnYcWkDu2jECIhvBWW4BqGeU86OwWXxxnddRtRU9gjeT cPBojivcT5+GWkRV7+vkTEWuKfno12RwVl41wifA= From: Greg Kroah-Hartman To: stable@vger.kernel.org Cc: Greg Kroah-Hartman , patches@lists.linux.dev, Will Porter , Takashi Iwai Subject: [PATCH 5.15 65/69] ALSA: usb-audio: Complete cleanup after system-resume errors Date: Mon, 31 Aug 2026 15:35:38 +0200 Message-ID: <20260831133401.986820509@linuxfoundation.org> X-Mailer: git-send-email 2.55.0 In-Reply-To: <20260831133358.601894154@linuxfoundation.org> References: <20260831133358.601894154@linuxfoundation.org> User-Agent: quilt/0.69 X-stable: review X-Patchwork-Hint: ignore Precedence: bulk X-Mailing-List: patches@lists.linux.dev List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Transfer-Encoding: 8bit 5.15-stable review patch. If anyone has any objections, please let me know. ------------------ From: Will Porter commit 1739a976312e110c93a8dee66a1cdf893a1b187e upstream. 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: Signed-off-by: Will Porter Link: https://patch.msgid.link/20260824225757.26749-1-mrwillporter@gmail.com Signed-off-by: Takashi Iwai Signed-off-by: Greg Kroah-Hartman --- sound/usb/card.c | 14 ++++++++++---- 1 file changed, 10 insertions(+), 4 deletions(-) --- a/sound/usb/card.c +++ b/sound/usb/card.c @@ -1121,8 +1121,11 @@ static int usb_audio_resume(struct usb_i 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; + } } /* @@ -1131,8 +1134,11 @@ static int usb_audio_resume(struct usb_i */ 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) {