From nobody Tue Apr 7 11:17:13 2026 Received: from pdx-out-005.esa.us-west-2.outbound.mail-perimeter.amazon.com (pdx-out-005.esa.us-west-2.outbound.mail-perimeter.amazon.com [52.13.214.179]) (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 A92893A1E96 for ; Fri, 13 Mar 2026 14:29:50 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=52.13.214.179 ARC-Seal: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1773412193; cv=none; b=kkzY/5/SpJiJ/bjEI1ihDdPKIIHFJlLP1qnMqv0kqBUUTNggBokCeLH7M3VLGl7djW0azbsdcnZx7YBuqLCWH9GkALvF8eI3YjLriOPQmRF/VV7qTkBUu91MikMAiVYjF3PfBT8I7+o8TXzrvhW3ECto+IUOVDhCDOdcy7RQtcU= ARC-Message-Signature: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1773412193; c=relaxed/simple; bh=4T6cjQh+S5bBWLrhwuIeX2gG7bAh6+2OBMOef1NLQmo=; h=From:To:CC:Subject:Date:Message-ID:MIME-Version:Content-Type; b=k02SB4J93EZC06QTKvedVxxcR5sqTamf9erZ5at2oipyZlbZYa/L12ShCJOmkry2fEUlgnn9BJdJZtmjOPAxvTGLR3gZuJw+Ts0ekQbXpjYbZbZ8i6sLe78pcyqcev0MaUyMhYac6ckynVtLma0bBYsd57EFoHPD/tPPVPxc12I= ARC-Authentication-Results: i=1; smtp.subspace.kernel.org; dmarc=pass (p=quarantine dis=none) header.from=amazon.com; spf=pass smtp.mailfrom=amazon.co.uk; dkim=pass (2048-bit key) header.d=amazon.com header.i=@amazon.com header.b=t4w3rbV6; arc=none smtp.client-ip=52.13.214.179 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=quarantine dis=none) header.from=amazon.com Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=amazon.co.uk Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=amazon.com header.i=@amazon.com header.b="t4w3rbV6" DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=amazon.com; i=@amazon.com; q=dns/txt; s=amazoncorp2; t=1773412190; x=1804948190; h=from:to:cc:subject:date:message-id:mime-version: content-transfer-encoding; bh=st0CJPKRkrEJjuuvqAcBeQPepQGyyzwT1orRtvFNKmQ=; b=t4w3rbV653nIHCaf/dEnI8e+nwhiU8x/6A1DjbcyPVI8UnGPgEYA79du Gm13BVkbYcqf41B953AFzw+yEzq3vi33zXvSkjCeqx3pdpY+VC16Mrpts G+Y1cX4jRqbfBy5OS3Zc8hI8teadaHC6GxxS1L38BEo9c3YXd3bHWIQEp eXq+4cJEKoG3ngy/3+bdcqU/Ip8kQZWzrQpBuIY+tSswjs78tw9D0k/Zp gbYoEeQASqVjXKOglDNX9H0EWI5XjyxlSWhz3d9uDUDnGsCKJv9DYDb9Q TTrJhDHcbyXfpfcvwRPmsOdTDyjAVIx4AaGqgW15XXKGPOBVNLdF7ymxn Q==; X-CSE-ConnectionGUID: 3PmTmp+kR4KMju2hTG/ikA== X-CSE-MsgGUID: fMIyfofFS0uQGWq2ft30XA== X-IronPort-AV: E=Sophos;i="6.23,118,1770595200"; d="scan'208";a="14975434" Received: from ip-10-5-12-219.us-west-2.compute.internal (HELO smtpout.naws.us-west-2.prod.farcaster.email.amazon.dev) ([10.5.12.219]) by internal-pdx-out-005.esa.us-west-2.outbound.mail-perimeter.amazon.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 13 Mar 2026 14:29:47 +0000 Received: from EX19MTAUWC002.ant.amazon.com [205.251.233.111:8086] by smtpin.naws.us-west-2.prod.farcaster.email.amazon.dev [10.0.23.137:2525] with esmtp (Farcaster) id 855d59a4-4fbb-4fa2-881d-d48c5808140e; Fri, 13 Mar 2026 14:29:47 +0000 (UTC) X-Farcaster-Flow-ID: 855d59a4-4fbb-4fa2-881d-d48c5808140e Received: from EX19D001UWA001.ant.amazon.com (10.13.138.214) by EX19MTAUWC002.ant.amazon.com (10.250.64.143) with Microsoft SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_128_CBC_SHA) id 15.2.2562.37; Fri, 13 Mar 2026 14:29:47 +0000 Received: from dev-dsk-connordw-1a-43da851f.eu-west-1.amazon.com (172.19.98.255) by EX19D001UWA001.ant.amazon.com (10.13.138.214) with Microsoft SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_128_CBC_SHA) id 15.2.2562.37; Fri, 13 Mar 2026 14:29:45 +0000 From: Connor Williamson To: , , CC: , , , Subject: [PATCH timers/core v1] clocksource: Align clocksource watchdog constraints with Kconfig value Date: Fri, 13 Mar 2026 14:29:28 +0000 Message-ID: <20260313142939.3023-1-connordw@amazon.com> X-Mailer: git-send-email 2.47.3 Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Transfer-Encoding: quoted-printable X-ClientProxiedBy: EX19D040UWA001.ant.amazon.com (10.13.139.22) To EX19D001UWA001.ant.amazon.com (10.13.138.214) Content-Type: text/plain; charset="utf-8" A previous patch intended to update both MAX_SKEW_USEC and CLOCKSOURCE_WATCHDOG_MAX_SKEW_US to 125 microseconds, resulting in a total tolerable skew per second of 500 microseconds as this value is doubled prior to being associated with the uncertainty_margin of a clocksource, and the uncertainty_margin values of two clocksources being compared are then summed before comparison to the skew. However, the default value of MAX_SKEW_USEC in the absence of the Kconfig option was defined as (125 * WATCHDOG_INTERVAL / HZ), which is (125 * (HZ >> 1)) / HZ, effectively ~ 125/2 microseconds, while CLOCKSOURCE_WATCHDOG_MAX_SKEW_US was set to 125 microseconds as intended. Therefore, align MAX_SKEW_USEC with CLOCKSOURCE_WATCHDOG_MAX_SKEW_US, setting it to the intended default value of 125 microseconds. 'Fixes: c37e85c135ce ("clocksource: Loosen clocksource watchdog constraints")' Signed-off-by: Connor Williamson --- kernel/time/clocksource.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/kernel/time/clocksource.c b/kernel/time/clocksource.c index e753a0632ac8..bd4aea8db2de 100644 --- a/kernel/time/clocksource.c +++ b/kernel/time/clocksource.c @@ -137,7 +137,7 @@ static u64 suspend_start; #ifdef CONFIG_CLOCKSOURCE_WATCHDOG_MAX_SKEW_US #define MAX_SKEW_USEC CONFIG_CLOCKSOURCE_WATCHDOG_MAX_SKEW_US #else -#define MAX_SKEW_USEC (125 * WATCHDOG_INTERVAL / HZ) +#define MAX_SKEW_USEC 125 #endif =20 /* --=20 2.47.3