From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from smtp.kernel.org (aws-us-west-2-korg-mail-alma10-1.taild15c8.ts.net [100.103.45.18]) (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 D9EEC37E5C0 for ; Wed, 9 Sep 2026 05:53:36 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=100.103.45.18 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1788933218; cv=none; b=EYNI6etACqY40yZH1UPwpy1cNaeYr/Cavh2Voquq2bsfcct3eQiRtt+rK5DUNUiNWBlxk1EFxPyTyt1k4wK5oc793bBYCjnemgNCgZEwov4yIaDJUvQsRDAme6nrVlGOFbzvJcPcSGeP/PCxI/1gg/qS6HPxJXaod0aIhwTIDtA= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1788933218; c=relaxed/simple; bh=7MRVNcNk+hkLDqv+YCHI8AWEcQhgXzV4nU9m7uSVvoQ=; h=From:Subject:To:Cc:In-Reply-To:References:Content-Type:Date: Message-Id; b=rBBmrmMtcEhWobfzkEFpH20QjLDIhQ0/73SElHF/XeHqg56AhRFCtHli4TaSWo6Sk33Y/d4pmP3zmAJcHpqO/BqXDpPkoAdTlCtsMwPASUDUCqhYJ3vojN+z/tmqSWuHc+Nr5GqVJFrcJSnzkIitoyU3PV5vsCqmfnefTi4wrU0= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b=IvYIAv6J; arc=none smtp.client-ip=100.103.45.18 Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b="IvYIAv6J" Received: by smtp.kernel.org (Postfix) with ESMTPSA id AC2F31F00A3A; Wed, 9 Sep 2026 05:53:36 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=kernel.org; s=k20260515; t=1788933216; bh=NBG12cjPEF22pKbZjnnzF8i2ucMeb+lb4pYArEjaWeI=; h=From:Subject:Reply-To:To:Cc:In-Reply-To:References:Date; b=IvYIAv6J7DMVUwSxIetTCfyHqmyp0NRzODQsBsiU0B0mHI6ymOPZLspo5chNIY3gA sE5/E4Gqm129cTRyh4NnWvQl8cgS321AaynGz0/lJfu4tHobAjpljjgHpPdEIao+dK T3UaOZmjh58NRKYlQAKVA8pwMa4SrNEmtwl/uqaHI/CGAUItnLebApad/CJ/0yfv5f 1hoz2NnfGbHXUZqIqL64UxSYrMFg/cc5fHmIzNDQSUnKg0IEuqh5RKhw3eZyAugLO2 c7L70l2vXBVrkGb5ljDZQTfvDK7ok6ETIrefJyFhxPHtJuENHHQH8j6GswizblEOLU u0OqqsyrhbLUA== From: sashiko-bot@kernel.org Subject: Re: [PATCH 6.18.y] mm/damon/vaddr: drop last same folio access check optimization Reply-To: sashiko-reviews@lists.linux.dev To: "SJ Park" Cc: damon@lists.linux.dev In-Reply-To: <20260909055038.259529-1-sj@kernel.org> References: <2026090857-overhear-pull-af4d@gregkh> <20260909055038.259529-1-sj@kernel.org> Content-Type: text/plain; charset=utf-8 Content-Transfer-Encoding: quoted-printable Date: Wed, 09 Sep 2026 05:53:36 +0000 Message-Id: <20260909055336.AC2F31F00A3A@smtp.kernel.org> Precedence: bulk X-Mailing-List: damon@lists.linux.dev List-Id: List-Subscribe: List-Unsubscribe: > The optimization can race when multiple kdamonds are running. Meanwhile, > the impact of the optimization is quite doubtful. Just remove it. >=20 > The user impact of the issue should be quite trivial. After all, the race > can happen only when the user intentionally setup DAMON in the way. Even > if it happens, it would be rare and only degrade the best-effort > monitoring results. No critical consequences like kernel panic or memory > corruption happen. >=20 > The race possibility was discovered [1] by Sashiko. >=20 > Link: https://lore.kernel.org/20260715031002.108504-4-sj@kernel.org > Link: https://lore.kernel.org/20260621204050.10993-1-sj@kernel.org [1] > Fixes: 3f49584b262c ("mm/damon: implement primitives for the virtual memo= ry address spaces") > Signed-off-by: SJ Park > Cc: # 5.15.x > Signed-off-by: Andrew Morton > (cherry picked from commit 831846078caa14b7d00b2ccca8b8fe522afe3204) > Signed-off-by: SJ Park Sashiko has reviewed this patch and found no issues. It looks great! --=20 Sashiko AI review =C2=B7 https://sashiko.dev/#/patchset/20260909055038.2595= 29-1-sj@kernel.org?part=3D1