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 8789712B94; Sat, 18 Apr 2026 07:54:56 +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=1776498896; cv=none; b=lsrHzVXmja2RQny1FF7TK18KGrrXYbeRiNZtKmR893H4fLKuckOUShUKNrTRHU7O1PsgCo96jfWk8OTdWHAM3Aqs5zyaBNUmDhDUxdF1hYl//SvtuSCmGct74SsV3xYxoEPcBeHhRhhqM4HL85RMYCwMtuGVuV5ANRlafdUiX80= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1776498896; c=relaxed/simple; bh=GKg6mIwnBZH7X7Tr8gU26RjRsB2YXA/so1+Jqkd+hVg=; h=Date:To:From:Subject:Message-Id; b=FCTSoyScXESXcUGyKuFc8LSmJDysrY/xE+vlZgUlVoxPwQKwwCFQkZhNZTls2/o77zG0fMUcE5dddfy12S4BLQ2tyesFrljPG2Z4DPHSIcz2Mv32IITC1H2I473EGktlNqt0WM5CjF27R2JZsA1rUSsZhpgKD83UuOUm/tQYfS0= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linux-foundation.org header.i=@linux-foundation.org header.b=Xgo5jSh1; arc=none smtp.client-ip=10.30.226.201 Authentication-Results: smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linux-foundation.org header.i=@linux-foundation.org header.b="Xgo5jSh1" Received: by smtp.kernel.org (Postfix) with ESMTPSA id 978F0C19424; Sat, 18 Apr 2026 07:54:55 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=linux-foundation.org; s=korg; t=1776498896; bh=GKg6mIwnBZH7X7Tr8gU26RjRsB2YXA/so1+Jqkd+hVg=; h=Date:To:From:Subject:From; b=Xgo5jSh1AdAFbG/JpRJxBvDdEWRxUyEBADmE3Qt1FTH4Q5lOyvSjixJhDzsDaJDzV X0MUvln042fAt5dHOwSHOI33tPxVaXOcLp3o6uCrrgdigpiWWOfnkAAbTFQWrl4gqN aRmB+Y/kFRZsmeNPtSF54eE5am5nQ5lOk+/a5F6I= Date: Sat, 18 Apr 2026 00:54:51 -0700 To: mm-commits@vger.kernel.org,stable@vger.kernel.org,sj@kernel.org,akpm@linux-foundation.org From: Andrew Morton Subject: [merged mm-stable] mm-damon-core-use-time_in_range_open-for-damos-quota-window-start.patch removed from -mm tree Message-Id: <20260418075455.978F0C19424@smtp.kernel.org> Precedence: bulk X-Mailing-List: stable@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: The quilt patch titled Subject: mm/damon/core: use time_in_range_open() for damos quota window start has been removed from the -mm tree. Its filename was mm-damon-core-use-time_in_range_open-for-damos-quota-window-start.patch This patch was dropped because it was merged into the mm-stable branch of git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm ------------------------------------------------------ From: SeongJae Park Subject: mm/damon/core: use time_in_range_open() for damos quota window start Date: Sun, 29 Mar 2026 08:23:05 -0700 damos_adjust_quota() uses time_after_eq() to show if it is time to start a new quota charge window, comparing the current jiffies and the scheduled next charge window start time. If it is, the next charge window start time is updated and the new charge window starts. The time check and next window start time update is skipped while the scheme is deactivated by the watermarks. Let's suppose the deactivation is kept more than LONG_MAX jiffies (assuming CONFIG_HZ of 250, more than 99 days in 32 bit systems and more than one billion years in 64 bit systems), resulting in having the jiffies larger than the next charge window start time + LONG_MAX. Then, the time_after_eq() call can return false until another LONG_MAX jiffies are passed. This means the scheme can continue working after being reactivated by the watermarks. But, soon, the quota will be exceeded and the scheme will again effectively stop working until the next charge window starts. Because the current charge window is extended to up to LONG_MAX jiffies, however, it will look like it stopped unexpectedly and indefinitely, from the user's perspective. Fix this by using !time_in_range_open() instead. The issue was discovered [1] by sashiko. Link: https://lore.kernel.org/20260329152306.45796-1-sj@kernel.org Link: https://lore.kernel.org/20260324040722.57944-1-sj@kernel.org [1] Fixes: ee801b7dd782 ("mm/damon/schemes: activate schemes based on a watermarks mechanism") Signed-off-by: SeongJae Park Cc: # 5.16.x Signed-off-by: Andrew Morton --- mm/damon/core.c | 3 ++- 1 file changed, 2 insertions(+), 1 deletion(-) --- a/mm/damon/core.c~mm-damon-core-use-time_in_range_open-for-damos-quota-window-start +++ a/mm/damon/core.c @@ -2449,7 +2449,8 @@ static void damos_adjust_quota(struct da } /* New charge window starts */ - if (time_after_eq(jiffies, quota->charged_from + + if (!time_in_range_open(jiffies, quota->charged_from, + quota->charged_from + msecs_to_jiffies(quota->reset_interval))) { if (damos_quota_is_set(quota) && quota->charged_sz >= quota->esz) _ Patches currently in -mm which might be from sj@kernel.org are mm-damon-core-disallow-time-quota-setting-zero-esz.patch mm-damon-core-disallow-non-power-of-two-min_region_sz-on-damon_start.patch