From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: From: Greg Kroah-Hartman To: linux-kernel@vger.kernel.org Cc: Greg Kroah-Hartman , stable@vger.kernel.org, Li Wang , Sage Weil Subject: [PATCH 3.4 21/43] ceph: Avoid data inconsistency due to d-cache aliasing in readpage() Date: Mon, 6 Jan 2014 14:39:38 -0800 Message-Id: <20140106223942.855284213@linuxfoundation.org> In-Reply-To: <20140106223942.259651490@linuxfoundation.org> References: <20140106223942.259651490@linuxfoundation.org> MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Sender: linux-kernel-owner@vger.kernel.org List-ID: 3.4-stable review patch. If anyone has any objections, please let me know. ------------------ From: Li Wang commit 56f91aad69444d650237295f68c195b74d888d95 upstream. If the length of data to be read in readpage() is exactly PAGE_CACHE_SIZE, the original code does not flush d-cache for data consistency after finishing reading. This patches fixes this. Signed-off-by: Li Wang Signed-off-by: Sage Weil Signed-off-by: Greg Kroah-Hartman --- fs/ceph/addr.c | 8 ++++++-- 1 file changed, 6 insertions(+), 2 deletions(-) --- a/fs/ceph/addr.c +++ b/fs/ceph/addr.c @@ -213,9 +213,13 @@ static int readpage_nounlock(struct file if (err < 0) { SetPageError(page); goto out; - } else if (err < PAGE_CACHE_SIZE) { + } else { + if (err < PAGE_CACHE_SIZE) { /* zero fill remainder of page */ - zero_user_segment(page, err, PAGE_CACHE_SIZE); + zero_user_segment(page, err, PAGE_CACHE_SIZE); + } else { + flush_dcache_page(page); + } } SetPageUptodate(page);