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 D205B1A08AB; Wed, 25 Sep 2024 11:53:30 +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=1727265211; cv=none; b=kwzhLtn+XZF8ArLVU+H3xwfSy4JEuN8pqxgfQEcCfYCfK810KWu//gO0H5+/tRMQ+/IYNLoHvILqYZ0pqrW1M8NqngZY6GfwVJzLuMwtodwa7aLLT6/A3piRjBY9hnz+fvdQsKeUmgnbAARmG729vR9gF7qxLkuxZnr7W1iW884= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1727265211; c=relaxed/simple; bh=gqUbvQt8vmr6+fqLEweAASRSTZ/+RqF0wVvOsjajWyU=; h=From:To:Cc:Subject:Date:Message-ID:In-Reply-To:References: MIME-Version; b=hlvCsvEmoL8cwW7Xl7ntA+2FVyK2W7/jxj99l7AxjcMutQXft4palFZucXhmXIgQMc0rFeRJwcpHiuibtmgolS2QnDBhasieNb+HxE8wIIgPzy55zAYCbZxcr3IsLFlSEVuLovqgJGOWRK+04tZV5l1rv57UQLIEuGLQaM2sx8s= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b=fgXw3DG4; arc=none smtp.client-ip=10.30.226.201 Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b="fgXw3DG4" Received: by smtp.kernel.org (Postfix) with ESMTPSA id 54955C4CECD; Wed, 25 Sep 2024 11:53:29 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1727265210; bh=gqUbvQt8vmr6+fqLEweAASRSTZ/+RqF0wVvOsjajWyU=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=fgXw3DG4bJQUA9pFZbN6qen1ct+WohKZI8KD+Sglymh7rZb1EE3WXGTyZ8+0janit ZXCAXQdxME9Z9V5SrRSuJ5IbhSJjNoXklsq7eU5ZdxhfAE0MaHK8qB3CwJwDVzDDqM kNPrThRfGWOzSb9ySbmNA2OAswc44Ql5C2B+eOZTaWfgy6hvNWhlyklsUv6VLvBsSf 023g9rmw5tmuKRJESEalRr0RGuUjNb+YLn1KTu4f2iiDeUuhnuQzYkrfTbkDe+iFUk 6DUCWEjpD6YiFeRBEUvPANU0QGNOMyhT3KLRp3HFBNhW+uC7hMu6cm8e+1H2Xv/kTn j8Sr+AGY58wPg== From: Sasha Levin To: linux-kernel@vger.kernel.org, stable@vger.kernel.org Cc: Christoph Hellwig , "Darrick J . Wong" , Christian Brauner , Sasha Levin , linux-xfs@vger.kernel.org, linux-fsdevel@vger.kernel.org Subject: [PATCH AUTOSEL 6.11 242/244] iomap: handle a post-direct I/O invalidate race in iomap_write_delalloc_release Date: Wed, 25 Sep 2024 07:27:43 -0400 Message-ID: <20240925113641.1297102-242-sashal@kernel.org> X-Mailer: git-send-email 2.43.0 In-Reply-To: <20240925113641.1297102-1-sashal@kernel.org> References: <20240925113641.1297102-1-sashal@kernel.org> Precedence: bulk X-Mailing-List: linux-xfs@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 X-stable: review X-Patchwork-Hint: Ignore X-stable-base: Linux 6.11 Content-Transfer-Encoding: 8bit From: Christoph Hellwig [ Upstream commit 7a9d43eace888a0ee6095035997bb138425844d3 ] When direct I/O completions invalidates the page cache it holds neither the i_rwsem nor the invalidate_lock so it can be racing with iomap_write_delalloc_release. If the search for the end of the region that contains data returns the start offset we hit such a race and just need to look for the end of the newly created hole instead. Signed-off-by: Christoph Hellwig Link: https://lore.kernel.org/r/20240910043949.3481298-2-hch@lst.de Reviewed-by: Darrick J. Wong Signed-off-by: Christian Brauner Signed-off-by: Sasha Levin --- fs/iomap/buffered-io.c | 10 +++++++++- 1 file changed, 9 insertions(+), 1 deletion(-) diff --git a/fs/iomap/buffered-io.c b/fs/iomap/buffered-io.c index d745f718bcde8..ca928cc9be49a 100644 --- a/fs/iomap/buffered-io.c +++ b/fs/iomap/buffered-io.c @@ -1241,7 +1241,15 @@ static int iomap_write_delalloc_release(struct inode *inode, error = data_end; goto out_unlock; } - WARN_ON_ONCE(data_end <= start_byte); + + /* + * If we race with post-direct I/O invalidation of the page cache, + * there might be no data left at start_byte. + */ + if (data_end == start_byte) + continue; + + WARN_ON_ONCE(data_end < start_byte); WARN_ON_ONCE(data_end > scan_end_byte); error = iomap_write_delalloc_scan(inode, &punch_start_byte, -- 2.43.0