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=1794591457; b=JF8bCRAskNnQdAY3U/LYZLFbQAh1W6NKK9yotJ+4ee3hKdO2fa5+unxZyseaF/szK0I9 ydeSbnyBp2nlNpCSOaVGX5/KSD8qpyh7V/52Ziwu4D7n43/FWm3kw4OV9hx/2LVOdmUTV P+6CdMhcMLX4pNuAav5HI01tyan0J278c5dTgnr19XY1Lldo7VeGAG0FfkGGClVnef9sm NwBzHa9udD5Dln8iKrHGQljRW0UEc/z15PPpGi2TpKbtJZOCloEEBuO5p2ebc824ujhwS IOV4CvqZr1R29hVAeHGmwk+eixvmbFJ4i3L94VZGztpYW3P4hQOAJuazVIJvdvAOrCg== ARC-Message-Signature: i=1; d=subspace.kernel.org; s=arc20261015; a=rsa-sha256; c=relaxed/relaxed; t=1794591457; 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=F072AKXfDrMfUeWmVp5nRJO4deSK1JKy9GG/T6REWuc=; b=WSornzNZI5y0QJo7QHO5FEEAJqAPeHmlRhxYBlYWRhAI+SDmItQvTOLJWddOFEEG9NBR 7Za0erjgjr+u1WOnOcDzAjd7MKoKKtDAtNhWioSdZ4rcPYH4/hbR8QvktTU3kTP0Rmu8J jZusGDkDYqLGXxtSYLtRlirgXXiY18rjt9qcIFXbVaNaH4aGEOZjggAP7FuGhGZpLaUO5 wKHntSfaee4w19KRozytZUy6fgWZpGA9KeK7S0un0s8cmHHjb2goTATPKGim16Ja4XK/c KyyyJt4WimHnrSG10Gv4KU4pbBX9QA8plEe20UB7x8Ua1ttQ728pBmtL4ZY8xQ6TzuA== 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=yEOyFfOi; 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 7ABC0607C36F; Fri, 13 Nov 2026 17:37:37 +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=yEOyFfOi Received: by smtp.kernel.org (Postfix) with ESMTPSA id 267CF1F000C4; Fri, 13 Nov 2026 17:37:37 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=linuxfoundation.org; s=korg; t=1794591457; bh=F072AKXfDrMfUeWmVp5nRJO4deSK1JKy9GG/T6REWuc=; h=From:To:Cc:Subject:Date:In-Reply-To:References; b=yEOyFfOiPI6UBCrZLJQxYBW6OG/tIOmI7VgWd7YA7LCPXz520utgiLkc+R1AFCmqG Gk4A3kYc+GMEI2lul4v2S0M8ACzvf+YZRi8d1JVlzRjRVR9s22vjkQEno7kq3Lww6n knnDD3jjD/OMLzHH5/S7PHnt1clSpwsVeLVbjDs8= 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 6.12 544/670] ALSA: mpu401: shut down timer before freeing MPU Date: Fri, 13 Nov 2026 10:51:48 -0500 Message-ID: <20261113153830.328617944@linuxfoundation.org> X-Mailer: git-send-email 2.56.0 In-Reply-To: <20261113153811.177190860@linuxfoundation.org> References: <20261113153811.177190860@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 6.12-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 [ sashal: Adapted scoped_guard() locking to the existing spin_lock_irqsave() and spin_unlock_irqrestore() calls. ] 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 8e3318e177179..86235aefab02d 100644 --- a/sound/drivers/mpu401/mpu401_uart.c +++ b/sound/drivers/mpu401/mpu401_uart.c @@ -162,14 +162,15 @@ static void snd_mpu401_uart_timer(struct timer_list *t) spin_lock_irqsave(&mpu->timer_lock, flags); /*mpu->mode |= MPU401_MODE_TIMER;*/ - mod_timer(&mpu->timer, 1 + jiffies); + if (mpu->timer_invoked) + mod_timer(&mpu->timer, 1 + jiffies); spin_unlock_irqrestore(&mpu->timer_lock, flags); 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) { @@ -177,7 +178,6 @@ static void snd_mpu401_uart_add_timer (struct snd_mpu401 *mpu, int input) spin_lock_irqsave (&mpu->timer_lock, flags); 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 : @@ -493,6 +493,7 @@ 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); } @@ -547,6 +548,7 @@ 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