From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from bombadil.infradead.org (bombadil.infradead.org [198.137.202.133]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.lore.kernel.org (Postfix) with ESMTPS id 43384C71155 for ; Mon, 16 Jun 2025 15:26:50 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=lists.infradead.org; s=bombadil.20210309; h=Sender:List-Subscribe:List-Help :List-Post:List-Archive:List-Unsubscribe:List-Id:Cc:To:In-Reply-To:References :Message-Id:Content-Transfer-Encoding:Content-Type:MIME-Version:Subject:Date: From:Reply-To:Content-ID:Content-Description:Resent-Date:Resent-From: Resent-Sender:Resent-To:Resent-Cc:Resent-Message-ID:List-Owner; bh=VfLRozBujaOByO5oe+/e5VFOdNzdj4Ycb5lWP+iT5j0=; b=Qh/En1KCq5AF+n/wzWpMVA1aNm Jzr8Wmlcmh5Kt8DGMPmr/7qSByl6sASpeObqjRqme08NMRSlPCsCfa30FWSZRWBcx21jsVtumVKKo /vzDKTo/xss13UxujTitVNROFq+HaVu//GWQpaGVllvHRC1TtDt4iIcQdpITj9Kir2Xrv0TebY8DE HNwvvd1Hh/dAaMBX/oNDnjtrKu8fEJq0OYLz9c49+DvEJminRQhfCApzoSqQLMXhUYZiS2zcI9bXD maihFpXvbbfwyipRO0KCj/auSCmMynWavoBlK5OEfv/DutM+IX3jjtMetP3eJaV2ISlB2bRZ4WYV6 z0QLhfCw==; Received: from localhost ([::1] helo=bombadil.infradead.org) by bombadil.infradead.org with esmtp (Exim 4.98.2 #2 (Red Hat Linux)) id 1uRBjM-00000004pxr-2Lnx; Mon, 16 Jun 2025 15:26:40 +0000 Received: from desiato.infradead.org ([2001:8b0:10b:1:d65d:64ff:fe57:4e05]) by bombadil.infradead.org with esmtps (Exim 4.98.2 #2 (Red Hat Linux)) id 1uR9fG-00000004VIf-0jQt for linux-arm-kernel@bombadil.infradead.org; Mon, 16 Jun 2025 13:14:18 +0000 DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=infradead.org; s=desiato.20200630; h=Cc:To:In-Reply-To:References: Message-Id:Content-Transfer-Encoding:Content-Type:MIME-Version:Subject:Date: From:Sender:Reply-To:Content-ID:Content-Description; bh=VfLRozBujaOByO5oe+/e5VFOdNzdj4Ycb5lWP+iT5j0=; b=MEOfbRMzz7aE6WSYgNJeR0EM9f TRfG2TV9iOO4zmODaR120xk/PSqMxiOeoeQI8X3quHAHPMCxMQS680VlFRhdPdFHzCNdahda/N90G jyLoPF9CKhQ28H3A848vCwJ19P8oCi1FsXKcXTIebJWiwzFGXRabkPikCkjgGsdLP63OFawaufCJy IPneMUOuCfrIPdzb/X6lxyindJ66ClW+qGHBFEsIqkoO6oeOKjsvLdvUeMgkagejQEiV8IGcxBif2 i4nOjiIJvtW2/AxFtnN70hHshQGFVG6NYZyQrfQffLueHXT+TYW1XXuosyu++2Tzh/YAiqVKzR10R 1HHT1sMQ==; Received: from pi.codeconstruct.com.au ([203.29.241.158] helo=codeconstruct.com.au) by desiato.infradead.org with esmtps (Exim 4.98.2 #2 (Red Hat Linux)) id 1uR9fB-00000003aQE-3F6p for linux-arm-kernel@lists.infradead.org; Mon, 16 Jun 2025 13:14:17 +0000 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 MIME-Version: 1.0 Content-Type: text/plain; charset="utf-8" Content-Transfer-Encoding: 7bit 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 X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.8.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20250616_141414_617753_31E9A493 X-CRM114-Status: GOOD ( 10.34 ) X-BeenThere: linux-arm-kernel@lists.infradead.org X-Mailman-Version: 2.1.34 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Sender: "linux-arm-kernel" Errors-To: linux-arm-kernel-bounces+linux-arm-kernel=archiver.kernel.org@lists.infradead.org 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 virtual address 00000004 when write [ 120.373866] [00000004] *pgd=00000000 [ 120.377910] Internal error: Oops: 805 [#1] SMP ARM [ 120.383306] CPU: 1 UID: 0 PID: 315 Comm: sh Not tainted 6.15.0-rc1-00009-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+0x188/0x200 ... 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/aspeed-lpc-snoop.c index 59c18afa649cd672f54f947066f468f2a78c0d5d..fc3a2c41cc10739f5f70ded7ac02baab6468d652 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 { }; 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_snoop *lpc_snoop, const struct aspeed_lpc_snoop_model_data *model_data = of_device_get_match_data(dev); + if (WARN_ON(lpc_snoop->chan[channel].enabled)) + return -EBUSY; + init_waitqueue_head(&lpc_snoop->chan[channel].wq); /* Create FIFO datastructure */ rc = kfifo_alloc(&lpc_snoop->chan[channel].fifo, @@ -236,6 +240,8 @@ static int aspeed_lpc_enable_snoop(struct aspeed_lpc_snoop *lpc_snoop, regmap_update_bits(lpc_snoop->regmap, HICRB, hicrb_en, hicrb_en); + lpc_snoop->chan[channel].enabled = true; + return 0; err_misc_deregister: @@ -248,6 +254,9 @@ static int aspeed_lpc_enable_snoop(struct aspeed_lpc_snoop *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; } + lpc_snoop->chan[channel].enabled = false; + /* Consider improving safety wrt concurrent reader(s) */ misc_deregister(&lpc_snoop->chan[channel].miscdev); kfifo_free(&lpc_snoop->chan[channel].fifo); } -- 2.39.5