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=1794064185; b=qQ8VjZiCWF03fM5wZlZgtssVLSI4onE7jZv4xpFsqhkVLbGaOWGYGLY9gAtXXXBlCZr/ ypLfMxgHB5vjfrPAxX/WiccuTLkNBpXmyOBHHKuG7ICqVTOYwuy9NFaXtZoMPhZnwuyo5 kqWygxqKpriDNTzkGI2Qew0WWirYcNEPrL8FGimpgxWQqHoaDQhbf/Xc6dkoFRA0b6Ylh 0kDoqMlhFQrJqca+0wv+JlOVWw7TnecD1/mSvL7hrY9IX7SZ+HkGIF2o/CMyF53We77lK a3pl/Oavxk7Z9Z4jlyIzFG73pAfYh08+Q/mLlC8PfLAGroH3cfPsbWy1RqJRCtYwndw== ARC-Message-Signature: i=1; d=subspace.kernel.org; s=arc20261015; a=rsa-sha256; c=relaxed/relaxed; t=1794064185; h=Received:DKIM-Signature:From:To:Cc:Subject:Date:Message-ID:X-Mailer: In-Reply-To:References:User-Agent:X-stable:X-Patchwork-Hint: MIME-Version:Content-Transfer-Encoding; bh=nqosCoYwSdOV+K9HClhDCBKUP0rbaOpZ+vE3p0A4Krc=; b=O/FDj4/RBa3mZzL3hdpJ08VYXGQ6+5/ctWtrHpnFyeYQDb1uzLArosm+sfdHjks1cQDy UZPR7Yr9nCfZU1Ciavk7HccadVV35hVtUJ37UoV2NTIIc9jpOGqZAyd3EwEVeLRIKX1Rf toiqYV0/Xtqn0GR4nteYxpJITTgHWmy5GabaXVAygGr6BqcqnrNvq/AqjwBqbJozccKpV 7SXdCvZpTNAtMVoUeHYFiiYbXyuM3kD4r/agBm2iYl/bGsqqGBQ6/OPRj8j0CWcrASw/q 5MKOJj99KcqrExGdph9Us5Gvd7DzM5KqAEoFysrLOlFOxoYQWkbRtWPGIpon49r1vcQ== ARC-Authentication-Results: i=1; smtp.subspace.kernel.org; dkim=pass header.d=linuxfoundation.org header.i=@linuxfoundation.org header.a=rsa-sha256 header.s=korg header.b=AemXPBmB; 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 90072606E8EF; Sat, 7 Nov 2026 15:09:45 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linuxfoundation.org header.i=@linuxfoundation.org header.a=rsa-sha256 header.s=korg header.b=AemXPBmB Received: by smtp.kernel.org (Postfix) with ESMTPSA id F01061F0089F; Sat, 7 Nov 2026 15:09:44 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=linuxfoundation.org; s=korg; t=1794064185; bh=nqosCoYwSdOV+K9HClhDCBKUP0rbaOpZ+vE3p0A4Krc=; h=From:To:Cc:Subject:Date:In-Reply-To:References; b=AemXPBmBMvCRZIQ+DPO/sHZ6KzgfpzpX78i2Y83Tr1wcfGi+YPR24RxkbdAGkzwpN PzAWWznDbtEbxVCuc3H29fhmnwvw0AACWaNYAw06ZfWEPPVH54gBMebHXt/j1jZ3d4 BaK/dLcPdAt/ReveJVEadBlyGPgIighnYOQ3eXC4= From: Greg Kroah-Hartman To: stable@vger.kernel.org Cc: Greg Kroah-Hartman , patches@lists.linux.dev, Runyu Xiao , Takashi Iwai , Sasha Levin Subject: [PATCH 7.3 0327/1257] ALSA: mpu401: shut down timer before freeing MPU Date: Sat, 7 Nov 2026 08:43:43 -0500 Message-ID: <20261107134948.456114132@linuxfoundation.org> X-Mailer: git-send-email 2.56.0 In-Reply-To: <20261107134939.434104957@linuxfoundation.org> References: <20261107134939.434104957@linuxfoundation.org> User-Agent: quilt/0.69 X-stable: review X-Patchwork-Hint: ignore 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-Transfer-Encoding: 8bit 7.3-stable review patch. If anyone has any objections, please let me know. ------------------ From: Runyu Xiao [ Upstream commit 9332af5220d42341bb1446a62c545c0518e990ef ] 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 Signed-off-by: Sasha Levin --- 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