From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from smtp.kernel.org (aws-us-west-2-korg-mail-1.web.codeaurora.org [10.30.226.201]) (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 0855C275AFB; Tue, 14 Apr 2026 20:55:06 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=10.30.226.201 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1776200106; cv=none; b=kJtsUuDBVXefHlQhixiDXskL0YjfWhxkFSadZRQOTscbw8+REmh9XigA6suwvuO1xF6h9J5EhspXOHt9Ogv+PmR4S6AhfzTHR0JN1cAGNMzq1mUwH2lT6wJFZrEq8Nt4BlGcgyfNTtwaktRCsK3uLuTcfjvHGm7Pcd985RSq/TI= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1776200106; c=relaxed/simple; bh=EDu18GVFDioQPQHdsolEuUt692hxrgbWXQqdtx2/xsg=; h=From:To:Cc:Subject:In-Reply-To:References:Date:Message-ID: MIME-Version:Content-Type; b=MRmLOktNKE03z3AgKUSv+pPN6YubUb+YWi6Kjs00SfnxdAEejgEbTBJ8jOApDaGYjpPQcT5Clzz5cQgFa1siCUnT2ZElHdoPPYpw/Z/FUBhSmmBXt656aDz7p2R4pt6NOXeFr+uYkpca9XmfYr6QdMrahppzQmTBg8zP7HlATws= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b=G0sc6Cc5; arc=none smtp.client-ip=10.30.226.201 Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b="G0sc6Cc5" Received: by smtp.kernel.org (Postfix) with ESMTPSA id D4D4BC19425; Tue, 14 Apr 2026 20:55:04 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1776200105; bh=EDu18GVFDioQPQHdsolEuUt692hxrgbWXQqdtx2/xsg=; h=From:To:Cc:Subject:In-Reply-To:References:Date:From; b=G0sc6Cc5UKUVzzxbQ16k8r9RRuAiMS6T5iAx4FH6QLNxGLx0j5r01VxJsc0UD417h XutpQWK+tHXTGKkkGk97epHbPm5dIxq1J5kTPyN0RhlM3h5JtGpqUHyB6/8kHCXmIc q/YHMB5/YqKPT8jniFghDr2L2RLBaVfoDHtRb7tvFd24xr3MZrZl6vFA0LPxPQLuHI aY8bGfCFsTemtxunJfZzCPh8q16CzXn/bRveQzqkEtfEuhc0HZ6dClesGUpEmbP3ku sTLCgFLw1mpk1zH4kO8fRpK2NcrRYoEnbrCWJ29fYz1+3MZjPjhJJMQL/eTw3BITbx jKxiG9TqOxECg== From: Thomas Gleixner To: Hanabishi , Frederic Weisbecker Cc: Eric Naim , LKML , Calvin Owens , Peter Zijlstra , Anna-Maria Behnsen , Ingo Molnar , John Stultz , Stephen Boyd , Alexander Viro , Christian Brauner , Jan Kara , linux-fsdevel@vger.kernel.org, Sebastian Reichel , linux-pm@vger.kernel.org, Pablo Neira Ayuso , Florian Westphal , Phil Sutter , netfilter-devel@vger.kernel.org, coreteam@netfilter.org Subject: Re: The "clockevents: Prevent timer interrupt starvation" patch causes lockups In-Reply-To: References: <20260407083219.478203185@kernel.org> <20260407083247.562657657@kernel.org> <68d1e9ac-2780-4be3-8ee3-0788062dd3a4@gmail.com> Date: Tue, 14 Apr 2026 22:55:01 +0200 Message-ID: <87340xfeje.ffs@tglx> Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Type: text/plain On Tue, Apr 14 2026 at 18:25, Hanabishi wrote: > On 14/04/2026 18:04, Frederic Weisbecker wrote: > > This patch doesn't help me unfortunately. Thanks. The one below should cover all possible holes. Thanks, tglx --- diff --git a/kernel/time/clockevents.c b/kernel/time/clockevents.c index b4d730604972..5e22697b098d 100644 --- a/kernel/time/clockevents.c +++ b/kernel/time/clockevents.c @@ -94,6 +94,9 @@ static int __clockevents_switch_state(struct clock_event_device *dev, if (dev->features & CLOCK_EVT_FEAT_DUMMY) return 0; + /* On state transitions clear the forced flag unconditionally */ + dev->next_event_forced = 0; + /* Transition with new state-specific callbacks */ switch (state) { case CLOCK_EVT_STATE_DETACHED: @@ -366,8 +369,10 @@ int clockevents_program_event(struct clock_event_device *dev, ktime_t expires, b if (delta > (int64_t)dev->min_delta_ns) { delta = min(delta, (int64_t) dev->max_delta_ns); cycles = ((u64)delta * dev->mult) >> dev->shift; - if (!dev->set_next_event((unsigned long) cycles, dev)) + if (!dev->set_next_event((unsigned long) cycles, dev)) { + dev->next_event_forced = 0; return 0; + } } if (dev->next_event_forced) diff --git a/kernel/time/tick-broadcast.c b/kernel/time/tick-broadcast.c index 7e57fa31ee26..115e0bf01276 100644 --- a/kernel/time/tick-broadcast.c +++ b/kernel/time/tick-broadcast.c @@ -108,6 +108,7 @@ static struct clock_event_device *tick_get_oneshot_wakeup_device(int cpu) static void tick_oneshot_wakeup_handler(struct clock_event_device *wd) { + wd->next_event_forced = 0; /* * If we woke up early and the tick was reprogrammed in the * meantime then this may be spurious but harmless.