From patchwork Thu Apr 13 20:48:23 2023 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Tyler Hicks X-Patchwork-Id: 13210652 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 vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id A6C4FC77B61 for ; Thu, 13 Apr 2023 20:48:55 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S229493AbjDMUsz (ORCPT ); Thu, 13 Apr 2023 16:48:55 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:39182 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S229854AbjDMUsy (ORCPT ); Thu, 13 Apr 2023 16:48:54 -0400 Received: from wout2-smtp.messagingengine.com (wout2-smtp.messagingengine.com [64.147.123.25]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 4E46193C9; Thu, 13 Apr 2023 13:48:52 -0700 (PDT) Received: from compute6.internal (compute6.nyi.internal [10.202.2.47]) by mailout.west.internal (Postfix) with ESMTP id 12C3E32009A9; Thu, 13 Apr 2023 16:48:51 -0400 (EDT) Received: from mailfrontend2 ([10.202.2.163]) by compute6.internal (MEProxy); Thu, 13 Apr 2023 16:48:51 -0400 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=tyhicks.com; h= cc:cc:content-transfer-encoding:content-type:date:date:from:from :in-reply-to:message-id:mime-version:reply-to:sender:subject :subject:to:to; s=fm2; t=1681418930; x=1681505330; bh=XKbPIBcAeh D9dQDK3VzDyoTlY+7K8DvNqjYIwyhgnaw=; b=h4e8kUBnCtcl5EdT+h18RV/CvK KURTVEsFDfNAdWvSnSJcO3y003ajKtaObY4E6TbkTVPBtoB+PGd3OGQDj3SjzTT+ KJmLqJiSyPgzNaU//ne5kugMwDv2x/o34UUG/FMXKh8sHL96Q/mtf8B29GpPbK+z OMDI4/r5o3Bg/fAL8q9EFB/2UmtmZ+OTT9+Kwtcqzko1Td2BYfsDFIDfun6YbwGe U7spXjdI1VbXSZE7jJxBTNSekpf+PdMQhDPRuqeyjtN0nw5v6qZYcYzXeCtgMX8U APuX2Aj2Hv+Gy+psjB0PPTDxMvj66s6GcTr41P2FoSnp5OG6ji+O+FSCK2iQ== DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d= messagingengine.com; h=cc:cc:content-transfer-encoding :content-type:date:date:feedback-id:feedback-id:from:from :in-reply-to:message-id:mime-version:reply-to:sender:subject :subject:to:to:x-me-proxy:x-me-proxy:x-me-sender:x-me-sender :x-sasl-enc; s=fm3; t=1681418930; x=1681505330; bh=XKbPIBcAehD9d QDK3VzDyoTlY+7K8DvNqjYIwyhgnaw=; b=bYwWhgEaQsP/JLWWYbrcIorL9Vdcg CI5u2t8bR45ucBkJhpzwhQmpyJyMJFja0kryt1WFtYR4fCZec4Uqv9U9oTYRUguY kScvLaTyw0tvbrRIhoI+aHSuNJotQF/wY8nN0LJjkUjLPftV+dplMufuWuWpy0dq DwUDa7BCmYZ404i4DntbPfg8Gc2kroiyBIJgmAZEj7Mimd9atQe2B1iaIjr2zx/q kPuMb4zRgS+gEkhobDTCtF5p+GQiqgPTIyMA2z8+5XKcoMAAjdxAYRcaJunyh/s6 0pKwYXZN/6hR15WKBGuULmBq21GI1+SxZGDAXKS7t3erHcZbb3Tm3Kr0Q== X-ME-Sender: X-ME-Received: X-ME-Proxy-Cause: gggruggvucftvghtrhhoucdtuddrgedvhedrvdekkedgudehhecutefuodetggdotefrod ftvfcurfhrohhfihhlvgemucfhrghsthforghilhdpqfgfvfdpuffrtefokffrpgfnqfgh necuuegrihhlohhuthemuceftddtnecusecvtfgvtghiphhivghnthhsucdlqddutddtmd enucfjughrpefhvfevufffkffoggfgsedtkeertdertddtnecuhfhrohhmpedfvfihlhgv rhcujfhitghkshculdfoihgtrhhoshhofhhtmddfuceotghouggvsehthihhihgtkhhsrd gtohhmqeenucggtffrrghtthgvrhhnpeeitdfgudeikefgheegfffhvdfgfedvfeevgeeh keegfffgudekveffvdejtedvieenucffohhmrghinhepkhgvrhhnvghlrdhorhhgnecuve hluhhsthgvrhfuihiivgeptdenucfrrghrrghmpehmrghilhhfrhhomheptghouggvseht hihhihgtkhhsrdgtohhm X-ME-Proxy: Feedback-ID: i78e14604:Fastmail Received: by mail.messagingengine.com (Postfix) with ESMTPA; Thu, 13 Apr 2023 16:48:49 -0400 (EDT) From: "Tyler Hicks (Microsoft)" To: stable@vger.kernel.org Cc: George Cherian , Guenter Roeck , Wim Van Sebroeck , linux-watchdog@vger.kernel.org Subject: [PATCH 5.10 5.4 4.19 4.14] watchdog: sbsa_wdog: Make sure the timeout programming is within the limits Date: Thu, 13 Apr 2023 15:48:23 -0500 Message-Id: <20230413204823.724485-1-code@tyhicks.com> X-Mailer: git-send-email 2.34.1 MIME-Version: 1.0 Precedence: bulk List-ID: X-Mailing-List: linux-watchdog@vger.kernel.org From: George Cherian [ Upstream commit 000987a38b53c172f435142a4026dd71378ca464 ] Make sure to honour the max_hw_heartbeat_ms while programming the timeout value to WOR. Clamp the timeout passed to sbsa_gwdt_set_timeout() to make sure the programmed value is within the permissible range. Fixes: abd3ac7902fb ("watchdog: sbsa: Support architecture version 1") Signed-off-by: George Cherian Reviewed-by: Guenter Roeck Link: https://lore.kernel.org/r/20230209021117.1512097-1-george.cherian@marvell.com Signed-off-by: Guenter Roeck Signed-off-by: Wim Van Sebroeck Signed-off-by: Tyler Hicks (Microsoft) Reviewed-by: Guenter Roeck --- The Fixes line in the original commit is incorrect. This commit fixes a bug that goes all the way back to v4.6 commit 57d2caaabfc7 ("Watchdog: introduce ARM SBSA watchdog driver") when only 32-bit Watchdog Offset Registers (WOR) were supported. Without this fix, there's a truncation on the first argument, of u32 type, passed to writel() in the following situation situation: Generic Watchdog architecture version is 1 (WOR is 32-bit) action is 1 timeout is 240s CNTFRQ_EL0 is 25000050 Hz wdd.max_hw_heartbeat_ms is 171s 25000050 * 240 = 6000012000 <--- requires 33 bits to store 6000012000 & 0xFFFFFFFF = 1705044704 <--- truncated value written to WOR 1705044704 / 25000050 = 68.2s <--- timeout incorrectly set to 68.2s The timeout from userspace is greater than wdd.max_hw_heartbeat_ms so the watchdog core pings at 69s (240 - 171) which results in intermittent and unexpected panics (action=1). With this patch applied, the timeout passed to writel() never exceeds 32-bits and the watchdog core + systemd keeps the watchdog happy. I've validated this fix on real hardware running a linux-5.10.y stable kernel. Please apply this patch to 5.10 through 4.14. Thanks! Tyler drivers/watchdog/sbsa_gwdt.c | 1 + 1 file changed, 1 insertion(+) diff --git a/drivers/watchdog/sbsa_gwdt.c b/drivers/watchdog/sbsa_gwdt.c index f0f1e3b2e463..4cbe6ba52754 100644 --- a/drivers/watchdog/sbsa_gwdt.c +++ b/drivers/watchdog/sbsa_gwdt.c @@ -121,6 +121,7 @@ static int sbsa_gwdt_set_timeout(struct watchdog_device *wdd, struct sbsa_gwdt *gwdt = watchdog_get_drvdata(wdd); wdd->timeout = timeout; + timeout = clamp_t(unsigned int, timeout, 1, wdd->max_hw_heartbeat_ms / 1000); if (action) writel(gwdt->clk * timeout,