From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from mail-wm1-f47.google.com (mail-wm1-f47.google.com [209.85.128.47]) (using TLSv1.2 with cipher ECDHE-RSA-AES128-GCM-SHA256 (128/128 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 7969640D56D for ; Sat, 27 Jun 2026 10:47:08 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=209.85.128.47 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1782557229; cv=none; b=pwGTOQs0pHQxeqsBjT38bltl3HFlNnKc67vxpGlbZ2IbPOabq/2v1HlfxRSBUaM+hR/eqCKDnevAzB3Zyw9xon82Kh1zhqpE8XuGHJz/HeSfTWikWsH3xnFmhPfXD3LpS3dJ/KCSXiD4a7gm5bs6i8iWWX8iEl7hs63IjtuvtQg= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1782557229; c=relaxed/simple; bh=6pHxHyWJUD3ftUhNZzXjTVg8hPVaPTh+cOba9zXGVRc=; h=From:To:Cc:Subject:In-Reply-To:MIME-Version:Content-Type: References:Date:Message-ID; b=CpNcr/yDZdlUQnIvpYuD25UYq/A+/8a4JOfFrDjpR8erooWIGmbB+3BWKqIMYUNQvq07x3i+dft+9XJv/7UURmUL3CD8+07S8l8jCQI/++cDcsNqU1RNa3ydztG8b+YdIHbgnrH7ZL5mzJdCIJAfZ6sm1+6Th3Jn2A3kteU73xI= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=gmail.com; spf=pass smtp.mailfrom=gmail.com; dkim=pass (2048-bit key) header.d=gmail.com header.i=@gmail.com header.b=BXQf2pgR; arc=none smtp.client-ip=209.85.128.47 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=gmail.com Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=gmail.com Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=gmail.com header.i=@gmail.com header.b="BXQf2pgR" Received: by mail-wm1-f47.google.com with SMTP id 5b1f17b1804b1-490b7866869so15346845e9.2 for ; Sat, 27 Jun 2026 03:47:08 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20251104; t=1782557227; x=1783162027; darn=vger.kernel.org; h=message-id:date:references:mime-version:in-reply-to:subject:cc:to :from:from:to:cc:subject:date:message-id:reply-to; bh=PgcKKFFDiI1sINhyMP2MXaZCJOFKbCazvuFE82CAKss=; b=BXQf2pgR2A0ZgfgMJm93MPCw1S2tQMcFM5HY98ZqiYKQ8+uxt9B1pleORkXN959XSG mUzZua+uWZgSFtTnlHui7rWSOpPHjL1gnP94xuP2kv3LMJxqp8jjCvF1v0qWd0uBdjoC AILIgKhCSqmVLTWqhyXE408b44NouGd/yC0QLdkds1YQ7YoVSU8H2md/QMpB//BTRvh+ KBRbBgzQ4x71LmNqXUIkEg6SBfBmgCMMTz48nOckLuapywnUFtZNlJBB6tEo31ItR54M BJ6SeEyjHtCdh9t3xZ/XARcaIe7whTo5pvK4FlJJ0maZdi5hSLDpXKOTvjSOBH4s6spp 3uiQ== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20251104; t=1782557227; x=1783162027; h=message-id:date:references:mime-version:in-reply-to:subject:cc:to :from:x-gm-gg:x-gm-message-state:from:to:cc:subject:date:message-id :reply-to; bh=PgcKKFFDiI1sINhyMP2MXaZCJOFKbCazvuFE82CAKss=; b=ZAxb9pdy+AjsjeaN/eyngMHbsSMmX0wZU2ERB80nBUt1i5ZjwBWAftku9pqRsOhx53 vPpdtTVEAsbzfEwVHqejWSKg/QWZItQKtpTZqGpb0CuBxRZfG6LE9gzI4W/aN/hE6nci xpT+NmaRTNNM+xl2o3R/DyzAN5elqIkEg1tVm/fImAEzvem9QtnUqXGod0vKan76gChK 9mUHlQUYHkCRGVN2mrLt2qtwWaDlM7GQXIcnVKrkkY1uwMZjqU7p0t38XspdH5MQ5Eaz ATnv6XIw2/5kOhU5MHPA13YbVJ9BR4pePEVQ98SpO+YXTPAq4lJzHHLHd5K1m9ofECxy RKjQ== X-Forwarded-Encrypted: i=1; AFNElJ9YgpHrYQa+S2VDr/wtoUjifc0IC5yCqsHWk67WajWdulqIk8vsCc+bHuNUgvZm8a/4/pSGUDxeQPyMH1Q=@vger.kernel.org X-Gm-Message-State: AOJu0Yx82S4MiBi2SZqXiFget7L/dx1SpiaopP6CGgjpwDZ3iNXHMXdH 8+c10CtaQxeWThbSUDQ2ycCWtovpk22TLhfWV4otdTseceAQLv+fJHR7I8tIzg== X-Gm-Gg: AfdE7clZnX/gLdKd7/W5km2AJN/S+kBwSyE49KVR8lfRYmRI5FxOLo80wR+5l7hGKO4 bVWbQFWmEsyL7Gh6lfVrrS2Znh04e4/+KEyulFSzHEgsD7hfQyoEuzgc4bgHUn50+tWyLUfsqZJ tBIIcck4E2bUaY1qUts+IyPiEB4uyUwth8DCNIAozmEKRZ8seGrYeyMaPrSuW31OEDub0to0Tuh nSmLzxIDmEedTZUA8WVL7L3I5PWtthT3wj8rFITJy0Id4UlgmZrhJhB4kv/WDisMbIS9NQAx2FX f4yNarkUGofyylVRD/fO06cLbYvQV1nZSkmAjgm8lhduiEyiVWbDZvkcaYy6uhYME+VXh+FY1dQ 71eZhPXf38xSKqUCP4bbexjVtyGq/e3PNDq6It90R9/5e0EFaCXp9eWJfJYoYfJtTEOi1p8J6Wb GK7tU/cCkPkW60sLTLP1rubes+qMGlAwM9U/bGkGhOOMvYBA== X-Received: by 2002:a05:600d:6405:20b0:490:bb3e:30b0 with SMTP id 5b1f17b1804b1-4926685feabmr119517985e9.4.1782557226603; Sat, 27 Jun 2026 03:47:06 -0700 (PDT) Received: from Abds-MacBook-Air.local ([141.2.113.129]) by smtp.gmail.com with ESMTPSA id ffacd0b85a97d-471490336d5sm3421142f8f.35.2026.06.27.03.47.05 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Sat, 27 Jun 2026 03:47:05 -0700 (PDT) From: Abd-Alrhman Masalkhi To: Chen Cheng , linux-raid@vger.kernel.org, yukuai@fygo.io Cc: chencheng@fnnas.com, linux-kernel@vger.kernel.org Subject: Re: [PATCH] md: protect read mddev->recovery in md_sync_action() In-Reply-To: <20260627102909.141036-1-chencheng@fnnas.com> Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Type: text/plain References: <20260627102909.141036-1-chencheng@fnnas.com> Hi Chen, Date: Sat, 27 Jun 2026 12:46:51 +0200 Message-ID: On Sat, Jun 27, 2026 at 18:29 +0800, Chen Cheng wrote: > From: Chen Cheng > > md_sync_action() read mddev->recovery in lockless path, use READ_ONCE() > instead of u64 plain read. > unisgned long is not always u64... I can not see what it fixes, is this just to silence KCSAN? If so, please say so in the commit message. > Fixes: e792a4c2156a3 ("md: add new helpers for sync_action") > > Signed-off-by: Chen Cheng > --- > drivers/md/md.c | 2 +- > 1 file changed, 1 insertion(+), 1 deletion(-) > > diff --git a/drivers/md/md.c b/drivers/md/md.c > index c5c50640b684..f4415c1a79d9 100644 > --- a/drivers/md/md.c > +++ b/drivers/md/md.c > @@ -5074,11 +5074,11 @@ static enum sync_action md_get_active_sync_action(struct mddev *mddev) > return is_recover ? ACTION_RECOVER : ACTION_IDLE; > } > > enum sync_action md_sync_action(struct mddev *mddev) > { > - unsigned long recovery = mddev->recovery; > + unsigned long recovery = READ_ONCE(mddev->recovery); > enum sync_action active_action; > > /* > * frozen has the highest priority, means running sync_thread will be > * stopped immediately, and no new sync_thread can start. > -- > 2.54.0 > -- Best Regards, Abd-Alrhman