From patchwork Mon Jun 17 22:01:35 2024 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Barry Song <21cnbao@gmail.com> X-Patchwork-Id: 13701487 Received: from mail-pf1-f177.google.com (mail-pf1-f177.google.com [209.85.210.177]) (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 0F4207492; Mon, 17 Jun 2024 22:03:29 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=209.85.210.177 ARC-Seal: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1718661811; cv=none; b=aYX/t22e7MWoAahoEhJP2vclDDNsFAhEt5glX47Nu0HQWadYrZ/j1H2UBCCEb8r4EAxFHOLcjHLYsu0cGcNO0/fnc/MtcVshWSL9KeR+x742p3hg9KaoY6AYb8dcJTt5KxjRResuDJ5ISwOZTjhYsS+vZ/LMLyA6gjMvnGKvLGQ= ARC-Message-Signature: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1718661811; c=relaxed/simple; bh=JeRfqVsQjqxDYKThVMdHv+1/FYBdVvbNZXaE7Z6ggS4=; h=From:To:Cc:Subject:Date:Message-Id:MIME-Version; b=GRvwlBMBo1WRssm5oRPAiw/sLOiwF6reCM8Y27Z4oLeXhpYFXyqAvXmfIQ3v3q7Z3ZnOKfQ+G6QppSKkCl0lZs9Cq8SMzwvBqlwZioFClScMVlILKW4YiNTBQkw5LMniU90iNLbGrbGMAQu+Kw/kl3tbsL1ssa/cHACIDqNqbow= 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=HIQeyxAk; arc=none smtp.client-ip=209.85.210.177 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="HIQeyxAk" Received: by mail-pf1-f177.google.com with SMTP id d2e1a72fcca58-7042cb2abc8so3506750b3a.0; Mon, 17 Jun 2024 15:03:29 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20230601; t=1718661809; x=1719266609; darn=vger.kernel.org; h=content-transfer-encoding:mime-version:message-id:date:subject:cc :to:from:from:to:cc:subject:date:message-id:reply-to; bh=OthT64InZoPSjxn4tC63hXPySB5WxWKH+1+hvHHCkCU=; b=HIQeyxAk+cqWDUVO+OE0FpqswN/W3iuaEBN6qvCddgNuZFKdWt3O5cFpXJFiQRLfNi R4b+akVKFYTRtS05AoVtHJXzbB2q9dthEXqEXNKn6lT78dnmtEVDPoCxucTSSoSOUXbA V2TxQs9+Y6bmhrG+hxxpgLVFu69VS2YBpgCdK4osIBrYDMFgTYMcCDXdyj84i47cBgEE 3frofH1Th3K3HuNXIB9GYvrXWXszh/G4toPRl2zRIX0cNWmm97ueW2h6Ahjt5D+BS7NI O/1xGxE1EsrZGDfYDjkizx7N4RoGC5mf0UEX24CGJtrtHFusx0DTUORhsufy6qCrs6o4 WXgA== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20230601; t=1718661809; x=1719266609; h=content-transfer-encoding:mime-version:message-id:date:subject:cc :to:from:x-gm-message-state:from:to:cc:subject:date:message-id :reply-to; bh=OthT64InZoPSjxn4tC63hXPySB5WxWKH+1+hvHHCkCU=; b=TRjy5uNi7yg1uaTS10MIoakYkxn7VY8Vpc1t0XCe/JPcs9bITWJwoU/tpoerm93WAR cEc9M4ldRPtB/mp8uxsxayQtDjeaDm+EkwH7+5yo7eYIDrQCz74YRGYxXcfExvzKNnkt VhKn/wFnI74112qepDkY5SMkMrie2OOw1KPahjEm9UGwXC6k+Ci/fpq0VNSvRpKemkOv gsOhIH3uAxUiDfVQ0/iu+Ll7TllupsfUnXUoDbXo4Id356zGjZ4XUE1RT0sVWx1NJ+i7 AEotyCc2FSE4OPQn5hX9vyE4IY+1qF0i3LmIe6gKeBHT7P6+5sBK+g11mcptnqvROrW+ KzOg== X-Forwarded-Encrypted: i=1; AJvYcCXNc1nUO95qiNdYSLTOkzj73Q09FsLEZm9R+Pe7yUrGNxmPbML8Z4szCvj7VvPb4+cQxq/Djsq3xOLd4g2f+AD4ScnasbxF6m/1s0vwWa503VAgzwW1KCbiYGD4fihpsIl8 X-Gm-Message-State: AOJu0Yzw8g0Xh7aKl3LUEPj6xbv6Dp4hLDzgc7XpstwMiuWYP3l95S8b HB4A1jBFMTnImYSuBaNBTWCENDtLsP9B1/qsjBniAPca4TzvbBEV X-Google-Smtp-Source: AGHT+IG9I5vkz7rxNTFokc77oylq1cp4BaWMyV8LYpDzB0f5nXtaQTES9UcpoMyRf5qpPVLsCCExLA== X-Received: by 2002:a05:6a21:6da3:b0:1b4:4370:60f with SMTP id adf61e73a8af0-1bae7e1c9e6mr11360428637.1.1718661809341; Mon, 17 Jun 2024 15:03:29 -0700 (PDT) Received: from localhost.localdomain ([2407:7000:8942:5500:aaa1:59ff:fe57:eb97]) by smtp.gmail.com with ESMTPSA id d2e1a72fcca58-705cc91dc5csm8079864b3a.10.2024.06.17.15.03.23 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Mon, 17 Jun 2024 15:03:28 -0700 (PDT) From: Barry Song <21cnbao@gmail.com> To: akpm@linux-foundation.org, linux-mm@kvack.org, linux-nfs@vger.kernel.org Cc: linux-cifs@vger.kernel.org, sfrench@samba.org, Barry Song , Christoph Hellwig , NeilBrown , Anna Schumaker , Trond Myklebust , Chuanhua Han , Ryan Roberts , Chris Li , "Huang, Ying" , Jeff Layton , stable@vger.kernel.org Subject: [PATCH] nfs: fix the incorrect assertion in nfs_swap_rw() Date: Tue, 18 Jun 2024 10:01:35 +1200 Message-Id: <20240617220135.43563-1-21cnbao@gmail.com> X-Mailer: git-send-email 2.34.1 Precedence: bulk X-Mailing-List: linux-cifs@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 From: Barry Song Since commit 2282679fb20b ("mm: submit multipage write for SWP_FS_OPS swap-space"), we can plug multiple pages then unplug them all together. That means iov_iter_count(iter) could be way bigger than PAGE_SIZE, it actually equals the size of iov_iter_npages(iter, INT_MAX). Note this issue has nothing to do with large folios as we don't support THP_SWPOUT to non-block devices. Fixes: 2282679fb20b ("mm: submit multipage write for SWP_FS_OPS swap-space") Reported-by: Christoph Hellwig Closes: https://lore.kernel.org/linux-mm/20240617053201.GA16852@lst.de/ Cc: NeilBrown Cc: Anna Schumaker Cc: Steve French Cc: Trond Myklebust Cc: Chuanhua Han Cc: Ryan Roberts Cc: Chris Li Cc: "Huang, Ying" Cc: Jeff Layton Cc: Signed-off-by: Barry Song --- fs/nfs/direct.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/fs/nfs/direct.c b/fs/nfs/direct.c index bb2f583eb28b..a1bfa86f467a 100644 --- a/fs/nfs/direct.c +++ b/fs/nfs/direct.c @@ -141,7 +141,7 @@ int nfs_swap_rw(struct kiocb *iocb, struct iov_iter *iter) { ssize_t ret; - VM_BUG_ON(iov_iter_count(iter) != PAGE_SIZE); + VM_WARN_ON(iov_iter_count(iter) != iov_iter_npages(iter, INT_MAX) * PAGE_SIZE); if (iov_iter_rw(iter) == READ) ret = nfs_file_direct_read(iocb, iter, true);