From nobody Fri Oct 10 03:59:39 2025 Received: from codeconstruct.com.au (pi.codeconstruct.com.au [203.29.241.158]) (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 395652DBF71; Mon, 16 Jun 2025 13:14:06 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=203.29.241.158 ARC-Seal: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1750079649; cv=none; b=citR2h5l7J2jjnN6rPfnFhhkMjWk/YUsMIwpiZXB9jQZgpCGEZSABBi1v2CNs5awPi1pbCDk3eNLkzNZEKC3A2Igl5XcZzMlyDHZrw7UehNJyG1VScvz+Kwi6eQYIKIoAiskAshINvniBK97MYVbXvDyRFJWwmP99nSDREtupkg= ARC-Message-Signature: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1750079649; c=relaxed/simple; bh=2avZu70uQr6eykvaOoyntQeSSbxUGmChsR39Zk4u8yg=; h=From:Date:Subject:MIME-Version:Content-Type:Message-Id:References: In-Reply-To:To:Cc; b=Pt6MJwsD5KddKqjZ+epFpcxchAGtw/UZLFskD0j1u0pcmg4ga9Tx9N2CDafBh5bXbASF69V/SBEV19atRVg3Fzec6zbkiYYgu1XkQXc5J0xHHivKyYjv/05ZyHloQS78p//B5uTEcbiT70XLs7L/S5L7ugavv4BhInsYFfbcn7M= ARC-Authentication-Results: i=1; smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=codeconstruct.com.au; spf=pass smtp.mailfrom=codeconstruct.com.au; dkim=pass (2048-bit key) header.d=codeconstruct.com.au header.i=@codeconstruct.com.au header.b=dly/STbT; arc=none smtp.client-ip=203.29.241.158 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=codeconstruct.com.au Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=codeconstruct.com.au Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=codeconstruct.com.au header.i=@codeconstruct.com.au header.b="dly/STbT" DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=codeconstruct.com.au; s=2022a; t=1750079639; bh=VfLRozBujaOByO5oe+/e5VFOdNzdj4Ycb5lWP+iT5j0=; h=From:Date:Subject:References:In-Reply-To:To:Cc; b=dly/STbTbitCQFrQxGFjzubD7pvkiPc2fD2pHhn7kSDZAdj8+1n+1yprkUy834Z/1 Tz7SS9azbqbu0Si2ANOjfzI+YyJ+uHyg5mxScX+NeDPvpEj5Uk3bhJUjld0MfK7sUU t7al5Qoa3yh7gZgujTXySn0CbppqmWigfN3inXlGAJI5bcvsOJ0pnafbHw2vU05GuN p/8GWWio2yJUAJ5htskd6b262YLfXxYbIm5pmhNKFVwF5fqZYKWq5OcOHDNTwQZ6bT XwWom+JX4Plp9LREtq7nHlsd/fTBO4DEpPQRtRoIDN9CtGiHa5SGZPM4RrfvuqU0ow ++bvZla3Bae1A== Received: from [127.0.1.1] (unknown [180.150.112.166]) by mail.codeconstruct.com.au (Postfix) with ESMTPSA id 72A406883E; Mon, 16 Jun 2025 21:13:58 +0800 (AWST) From: Andrew Jeffery Date: Mon, 16 Jun 2025 22:43:39 +0930 Subject: [PATCH v2 02/10] soc: aspeed: lpc-snoop: Don't disable channels that aren't enabled Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Type: text/plain; charset="utf-8" Content-Transfer-Encoding: quoted-printable Message-Id: <20250616-aspeed-lpc-snoop-fixes-v2-2-3cdd59c934d3@codeconstruct.com.au> References: <20250616-aspeed-lpc-snoop-fixes-v2-0-3cdd59c934d3@codeconstruct.com.au> In-Reply-To: <20250616-aspeed-lpc-snoop-fixes-v2-0-3cdd59c934d3@codeconstruct.com.au> To: linux-aspeed@lists.ozlabs.org Cc: Joel Stanley , Henry Martin , Jean Delvare , Patrick Rudolph , Andrew Geissler , Ninad Palsule , Patrick Venture , Robert Lippert , linux-arm-kernel@lists.infradead.org, linux-kernel@vger.kernel.org, Andrew Jeffery , stable@vger.kernel.org X-Mailer: b4 0.14.2 Mitigate e.g. the following: # echo 1e789080.lpc-snoop > /sys/bus/platform/drivers/aspeed-lpc-snoop/= unbind ... [ 120.363594] Unable to handle kernel NULL pointer dereference at virt= ual address 00000004 when write [ 120.373866] [00000004] *pgd=3D00000000 [ 120.377910] Internal error: Oops: 805 [#1] SMP ARM [ 120.383306] CPU: 1 UID: 0 PID: 315 Comm: sh Not tainted 6.15.0-rc1-0= 0009-g926217bc7d7d-dirty #20 NONE ... [ 120.679543] Call trace: [ 120.679559] misc_deregister from aspeed_lpc_snoop_remove+0x84/0xac [ 120.692462] aspeed_lpc_snoop_remove from platform_remove+0x28/0x38 [ 120.700996] platform_remove from device_release_driver_internal+0x1= 88/0x200 ... Fixes: 9f4f9ae81d0a ("drivers/misc: add Aspeed LPC snoop driver") Cc: stable@vger.kernel.org Cc: Jean Delvare Acked-by: Jean Delvare Signed-off-by: Andrew Jeffery --- drivers/soc/aspeed/aspeed-lpc-snoop.c | 11 +++++++++++ 1 file changed, 11 insertions(+) diff --git a/drivers/soc/aspeed/aspeed-lpc-snoop.c b/drivers/soc/aspeed/asp= eed-lpc-snoop.c index 59c18afa649cd672f54f947066f468f2a78c0d5d..fc3a2c41cc10739f5f70ded7ac0= 2baab6468d652 100644 --- a/drivers/soc/aspeed/aspeed-lpc-snoop.c +++ b/drivers/soc/aspeed/aspeed-lpc-snoop.c @@ -58,6 +58,7 @@ struct aspeed_lpc_snoop_model_data { }; =20 struct aspeed_lpc_snoop_channel { + bool enabled; struct kfifo fifo; wait_queue_head_t wq; struct miscdevice miscdev; @@ -190,6 +191,9 @@ static int aspeed_lpc_enable_snoop(struct aspeed_lpc_sn= oop *lpc_snoop, const struct aspeed_lpc_snoop_model_data *model_data =3D of_device_get_match_data(dev); =20 + if (WARN_ON(lpc_snoop->chan[channel].enabled)) + return -EBUSY; + init_waitqueue_head(&lpc_snoop->chan[channel].wq); /* Create FIFO datastructure */ rc =3D kfifo_alloc(&lpc_snoop->chan[channel].fifo, @@ -236,6 +240,8 @@ static int aspeed_lpc_enable_snoop(struct aspeed_lpc_sn= oop *lpc_snoop, regmap_update_bits(lpc_snoop->regmap, HICRB, hicrb_en, hicrb_en); =20 + lpc_snoop->chan[channel].enabled =3D true; + return 0; =20 err_misc_deregister: @@ -248,6 +254,9 @@ static int aspeed_lpc_enable_snoop(struct aspeed_lpc_sn= oop *lpc_snoop, static void aspeed_lpc_disable_snoop(struct aspeed_lpc_snoop *lpc_snoop, int channel) { + if (!lpc_snoop->chan[channel].enabled) + return; + switch (channel) { case 0: regmap_update_bits(lpc_snoop->regmap, HICR5, @@ -263,6 +272,8 @@ static void aspeed_lpc_disable_snoop(struct aspeed_lpc_= snoop *lpc_snoop, return; } =20 + lpc_snoop->chan[channel].enabled =3D false; + /* Consider improving safety wrt concurrent reader(s) */ misc_deregister(&lpc_snoop->chan[channel].miscdev); kfifo_free(&lpc_snoop->chan[channel].fifo); } --=20 2.39.5