From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from mail-pf1-f176.google.com (mail-pf1-f176.google.com [209.85.210.176]) (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 2098D1F948 for ; Wed, 3 Sep 2025 02:28:17 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=209.85.210.176 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1756866500; cv=none; b=RQSCj8xkpG6TrnEcn5BVFFwMftgzr4wf0Lllt43HQ/u/5RvJb3RRDC0ij32Ipu/ilFEjCw1PV7SszE0XE3qpLOwOpIZhJDrxAKKz77a0PI8q3aFACVTT1LeG+XVvvtsIm+Rvyrh8p00b+NiVpvzs3KQmYJAD4tF96DTdEnvi7eM= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1756866500; c=relaxed/simple; bh=w632ilYPA2n+P2XmlWidLkI0dfcbmCHlhpvh3mQsJtA=; h=From:To:Cc:Subject:Date:Message-ID:In-Reply-To:References: MIME-Version; b=PzOawLI5G8NZts4+DET+iYUzNwF+hTp7tm8h7afw2n/sraaX6Pfb9ISbRLy6d5ptWwpEYGvAT4vXEMCopjl9ybgisFoBpBzf6iRib2a+rvcU/mL9V1odNztVJNsg3UWo+8K4Y597m1JZh6lYWyrhauNCHnRh7nGx9wde8hOA/iU= 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=k/Ks2cjC; arc=none smtp.client-ip=209.85.210.176 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="k/Ks2cjC" Received: by mail-pf1-f176.google.com with SMTP id d2e1a72fcca58-77256200f1bso2179723b3a.3 for ; Tue, 02 Sep 2025 19:28:17 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20230601; t=1756866497; x=1757471297; darn=vger.kernel.org; h=content-transfer-encoding:mime-version:references:in-reply-to :message-id:date:subject:cc:to:from:from:to:cc:subject:date :message-id:reply-to; bh=lblPTgYeGtHNKfvL2n8eI3SsVmG/1mWE9ZXzzIlkWfo=; b=k/Ks2cjCllUCO0lzYRHdSxrUUIOWewzooVr7cVF9r6LrEtvt0QvjkL9A21ZhPi7Pi6 9t63W6WihUnr8Qbz7B1epoY02OayD6TiVVVl+ZjWKs4LHUuNJ8z5D2fZV0OdbyT/+9j4 uee4w3vrDp4VCnFsWQgsegMeq1AYDCbY9Vnhvdjr72z0pgvGsCo4GxzYpp3UJa2siysN wR/Y+hdxj8/n6eA6JI+PITguYTNStdhOAG9g53Dchbo0JyX9NVTiyvyyfikCIL7eP8Sc ff42STbtaI967ZKl2eq9zVaG7/qV3ShznJIYfZKuWmfHD8nFhinDPx1gKSooLWnO/oDb fTkw== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20230601; t=1756866497; x=1757471297; h=content-transfer-encoding:mime-version:references:in-reply-to :message-id:date:subject:cc:to:from:x-gm-message-state:from:to:cc :subject:date:message-id:reply-to; bh=lblPTgYeGtHNKfvL2n8eI3SsVmG/1mWE9ZXzzIlkWfo=; b=k5NEJexoyM6jzeg28Ef1aBpDIVI3RQNxST2WUmV7Wuqx8PZqzZ4+o95WuaBk/t22Vn iBChAwcTm2v3b7KzfOYnAoUFIN8iAGKAYICH0I8b33NrF5Zz0EVHqCjBMeGEJOFSw9wo W+VsykboTHCyctTpAd9G0f7HZaociGQ5sjB58a7Fppx/US72Zz9rV5ZD8zLmP/g/RdCH hAIqGn+fNVyb6fb1Fr8kTsFmh2xJL558w4FLEgGn7G4YMcKEqBecI+QLQHnYSTsUzihU gVAlxQ0GCAnzy3Wi/050L+Svix6NTYrJY0447n9jRq5QCn/d1ZLEXSCrup6bh3v7I7rs U96g== X-Gm-Message-State: AOJu0Yy4yaKEo4KmxlUgVAliPojDrXQL0YpVKDebu6kXkIrzjaveUbbL PqyJpf0aJQzXJYJf2V99NW9xjKXsteaVkLVGser6p6Pxgg1z70HAPVkHVSxXAUijOFE= X-Gm-Gg: ASbGncswrecSxt9f8dHKFifKgq/OWMAO14QVchu4e+kIV9jpQ5y3OxK8gnodpd769eT 5PNKAWJ7EdYizjjLQiAiCxXuazywNk4OZQqIhvyUHHxxobRVZJxU9BuwKsJQu7PGuXWpv1vSMZq akV/N5WiNEZYCAkI1EPTO47WC3lulBrFXXpkKQ9X/R5lr+9FhuZYDqut+eCxai0Sukz6F8wNHaC rRSGqumDm6h05kNIh80qCbNXRm+TwZLLbix+DU7NXU30x3zUi5e1Lmfrye/zDcGdJTI30Vg0caM p/mPmfaHVVDnp0eEIEVaOG4cp6XME/lQQpwj2WF9RSi1g2e4N/165Fuw/iSNAZ/wrVeLKGJw27X /uUlW+2LKw1k1R8NQPuSBVfBPnsfI0X0R X-Google-Smtp-Source: AGHT+IE42RwQvXyPWDBN+hqUx2NOehVNn+CUJKgQ553VY7ewX3Z/PmGBO9TJRJkDg/JwSlG/TCAkUg== X-Received: by 2002:a05:6a20:5483:b0:243:ac37:821 with SMTP id adf61e73a8af0-243d6f4243emr18708767637.48.1756866497153; Tue, 02 Sep 2025 19:28:17 -0700 (PDT) Received: from yangwen.localdomain ([117.88.134.52]) by smtp.gmail.com with ESMTPSA id d2e1a72fcca58-7722a4bbe10sm15049217b3a.56.2025.09.02.19.28.15 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Tue, 02 Sep 2025 19:28:16 -0700 (PDT) From: YangWen To: hirofumi@mail.parknet.co.jp Cc: linux-kernel@vger.kernel.org Subject: Re: [PATCH] fat: fix data-race between fat12_ent_put() and fat_mirror_bhs() Date: Wed, 3 Sep 2025 10:28:15 +0800 Message-ID: <20250903022815.109-1-anmuxixixi@gmail.com> X-Mailer: git-send-email 2.43.0 In-Reply-To: <874itk20j2.fsf@mail.parknet.co.jp> References: <874itk20j2.fsf@mail.parknet.co.jp> Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Transfer-Encoding: 8bit Hi, OGAWA Hirofumi wrote: > Sync mount doesn't try to keep all of consistency. It is trying to keep > sync the minimum blocks for consistency. The primary should be always > consistent, however this doesn't care much about mirror FAT. Thanks a lot for your explanation. I understand your point and you are right.I just noticed that in fat_mirror_bhs(), the buffer head "c_bh" actually represents the mirror FAT blocks, and the code does: if (sb->s_flags & SB_SYNCHRONOUS) err = sync_dirty_buffer(c_bh); So on -o sync mounts the mirror FAT blocks are also forced to disk immediately. Thanks.