From mboxrd@z Thu Jan 1 00:00:00 1970 Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.remote-ip=100.103.45.18 ARC-Seal: i=1; d=subspace.kernel.org; s=arc20261015; a=rsa-sha256; cv=none; t=1794046680; b=Bso+Hw+nkWuStQhOC4ZgxrhLRtpUlJik+evEvcHV42LP4d5Ec4zHDw7BZh2d+GqSEwjP vbV0Hv+tuQoalMUQf2halQ+/10F3e+xYs1kbfT+CiN2KPUlTn+XtaX9lWFynMRiioRUvp nhqyBKyxouR0W+wUmE1rSZ1shvKvr+jZBTUYm0WTsjKnbqbq1gvgjP5qXjx0WJ/li4UVx ChZ8l2uCJy6AJlrvA1owz8PqswxCpf46CSX8zXTFZ+cRHE24s4+kW/HP61yui9Jr8566X GRrVSFvl+dBmeQ2zviHfa36Jdz0DMALimxkxCxnIeoGUANN5qjOdg6F5ezpY3w4kKTA== ARC-Message-Signature: i=1; d=subspace.kernel.org; s=arc20261015; a=rsa-sha256; c=relaxed/relaxed; t=1794046680; h=Received:DKIM-Signature:From:To:Cc:Subject:Date:Message-ID:X-Mailer: MIME-Version:Content-Type:Content-Transfer-Encoding; bh=yhWcVKMtpulUOjlpJ7X08lJqk6bA153O/lhnHUkwJQE=; b=pP4/lnYN9A6n+Q265CQVawhb0nznDm5aU9YMY85eLxt58/GKdnDOwfJmzwWchtoV+HQU o0RWj1xCm5FxWk+fpRAzh0747lta8RdvvllOqjhkfAhrzRH/fG8MMsGcbOiDdNS7nSPuI C7Aiz3FBp+HzpD4XlWyR94PyJhCHFDTEGbxMPnf31zxGbSe87sGAQq5BZq/1yoqiaZFup CkSM6846HgYsrvZvFRw8RmXb8g7lXRXBu4eOQ4mEPtwKyQwyuSPOcOQcegsWitUKhpzkw bgNqz3gsIk2GOijfM0OkleVl9qpYBPnHRsojo2ISNBRlwxk22eReW9Fk10V4BxUxmzw== ARC-Authentication-Results: i=1; smtp.subspace.kernel.org; dkim=pass header.d=kernel.org header.i=@kernel.org header.a=rsa-sha256 header.s=k20260515 header.b=lJZiXLem; arc=none smtp.remote-ip=100.103.45.18 Received: from smtp.kernel.org (quasi.space.kernel.org [100.103.45.18]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits) key-exchange X25519 server-signature ECDSA (prime256v1)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id E79BE6082BD5 for ; Sat, 7 Nov 2026 10:17:59 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.a=rsa-sha256 header.s=k20260515 header.b=lJZiXLem Received: by smtp.kernel.org (Postfix) with ESMTPSA id 5EE391F0089F; Sat, 7 Nov 2026 10:17:59 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=kernel.org; s=k20260515; t=1794046679; bh=yhWcVKMtpulUOjlpJ7X08lJqk6bA153O/lhnHUkwJQE=; h=From:To:Cc:Subject:Date; b=lJZiXLem3kmBOPolZGwuiBXFzLtezojWz4bG2jybhMU9BRf58F6y2kSzPenncuDaN 4wd9wJ1cODADL5RLTyk78B0fu55OPJUiEoVmwrhxsaqN8WcGzypO3ptPGak67GyoLa 6yjjAe3YsuhetrO3IgB2pp9VVuO5sqix2oqXYtUv3xmuxooj1X5fJJhSGpOR00yyFa A6Dm1XOmPwZ84HTg9gwEnEo3jFqrucqmJggi0HM7WUaIoqags0VKXm7ene+Yx7On9j w/VTT9kxUeGz4ciAd8g87ITKru2Ck09PNAo1Mf9QizqsUarDUFx3qplji16cBSMIFN 92Ntr6p5oXPKg== From: Sasha Levin To: runyu.xiao@seu.edu.cn, tiwai@suse.de Cc: stable@vger.kernel.org Subject: FAILED: patch "[PATCH] ALSA: mpu401: shut down timer before freeing MPU" failed to apply to 6.12-stable tree Date: Sat, 7 Nov 2026 05:17:58 -0500 Message-ID: <20261107051758-failed-6.12-9332af5220d4@kernel.org> X-Mailer: git-send-email 2.53.0 X-Mailing-List: stable@vger.kernel.org List-Id: List-Post: List-Help: List-Subscribe: List-Unsubscribe: List-Owner: Precedence: list MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit The patch below does not apply to the 6.12-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 . 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-6.12.y git checkout FETCH_HEAD git cherry-pick -x 9332af5220d42341bb1446a62c545c0518e990ef # git commit -s git send-email --to '' --in-reply-to '20261107051758-failed-6.12-9332af5220d4@kernel.org' --subject-prefix 'PATCH 6.12.y' 'HEAD^..' Thanks, Sasha ------------------ original commit in Linus's tree ------------------ >From 9332af5220d42341bb1446a62c545c0518e990ef Mon Sep 17 00:00:00 2001 From: Runyu Xiao Date: Sun, 27 Sep 2026 17:38:09 +0800 Subject: [PATCH] ALSA: mpu401: shut down timer before freeing MPU When an MPU401 interface has no usable IRQ, the driver polls raw-MIDI input and output with a timer. During raw-MIDI teardown, the timer callback can already be running when snd_mpu401_uart_remove_timer() clears the last mode bit and calls timer_delete(). That API neither waits for a running callback nor prevents it from rearming the timer, and free_irq() does not synchronize timer callbacks. snd_mpu401_uart_free() can therefore release mpu while the timer callback still uses it. Initialize the timer once when the MPU object is created and only rearm it while a timer mode is active. Shut it down synchronously after freeing the IRQ so an in-flight callback completes before mpu and its resources are released. Fixes: 1da177e4c3f4 ("Linux-2.6.12-rc2") Cc: stable@vger.kernel.org Assisted-by: LLM Signed-off-by: Runyu Xiao Link: https://patch.msgid.link/20260927093809.681726-1-runyu.xiao@seu.edu.cn Signed-off-by: Takashi Iwai --- sound/drivers/mpu401/mpu401_uart.c | 8 +++++--- 1 file changed, 5 insertions(+), 3 deletions(-) diff --git a/sound/drivers/mpu401/mpu401_uart.c b/sound/drivers/mpu401/mpu401_uart.c index 6de03d72a9087..fcf2b686f9f5e 100644 --- a/sound/drivers/mpu401/mpu401_uart.c +++ b/sound/drivers/mpu401/mpu401_uart.c @@ -155,20 +155,20 @@ static void snd_mpu401_uart_timer(struct timer_list *t) scoped_guard(spinlock_irqsave, &mpu->timer_lock) { /*mpu->mode |= MPU401_MODE_TIMER;*/ - mod_timer(&mpu->timer, 1 + jiffies); + if (mpu->timer_invoked) + mod_timer(&mpu->timer, 1 + jiffies); } if (mpu->rmidi) _snd_mpu401_uart_interrupt(mpu); } /* - * initialize the timer callback if not programmed yet + * arm the timer if it is not already active */ static void snd_mpu401_uart_add_timer (struct snd_mpu401 *mpu, int input) { guard(spinlock_irqsave)(&mpu->timer_lock); if (mpu->timer_invoked == 0) { - timer_setup(&mpu->timer, snd_mpu401_uart_timer, 0); mod_timer(&mpu->timer, 1 + jiffies); } mpu->timer_invoked |= input ? MPU401_MODE_INPUT_TIMER : @@ -474,6 +474,7 @@ static void snd_mpu401_uart_free(struct snd_rawmidi *rmidi) struct snd_mpu401 *mpu = rmidi->private_data; if (mpu->irq >= 0) free_irq(mpu->irq, (void *) mpu); + timer_shutdown_sync(&mpu->timer); release_and_free_resource(mpu->res); kfree(mpu); } @@ -528,6 +529,7 @@ int snd_mpu401_uart_new(struct snd_card *card, int device, spin_lock_init(&mpu->input_lock); spin_lock_init(&mpu->output_lock); spin_lock_init(&mpu->timer_lock); + timer_setup(&mpu->timer, snd_mpu401_uart_timer, 0); mpu->hardware = hardware; mpu->irq = -1; mpu->rmidi = rmidi; -- 2.53.0