From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1752445AbdCNN2u (ORCPT ); Tue, 14 Mar 2017 09:28:50 -0400 Received: from mx2.suse.de ([195.135.220.15]:40304 "EHLO mx2.suse.de" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751608AbdCNNQM (ORCPT ); Tue, 14 Mar 2017 09:16:12 -0400 X-Amavis-Alert: BAD HEADER SECTION, Duplicate header field: "References" From: Jiri Slaby To: stable@vger.kernel.org Cc: linux-kernel@vger.kernel.org, Jan Kara , "Theodore Ts'o" , Jiri Slaby Subject: [PATCH 3.12 26/60] ext4: trim allocation requests to group size Date: Tue, 14 Mar 2017 14:15:17 +0100 Message-Id: X-Mailer: git-send-email 2.12.0 In-Reply-To: References: In-Reply-To: References: Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org From: Jan Kara 3.12-stable review patch. If anyone has any objections, please let me know. =============== commit cd648b8a8fd5071d232242d5ee7ee3c0815776af upstream. If filesystem groups are artifically small (using parameter -g to mkfs.ext4), ext4_mb_normalize_request() can result in a request that is larger than a block group. Trim the request size to not confuse allocation code. Reported-by: "Kirill A. Shutemov" Signed-off-by: Jan Kara Signed-off-by: Theodore Ts'o Signed-off-by: Jiri Slaby --- fs/ext4/mballoc.c | 7 +++++++ 1 file changed, 7 insertions(+) diff --git a/fs/ext4/mballoc.c b/fs/ext4/mballoc.c index 2b4ed2bf9569..16a763af556c 100644 --- a/fs/ext4/mballoc.c +++ b/fs/ext4/mballoc.c @@ -3084,6 +3084,13 @@ ext4_mb_normalize_request(struct ext4_allocation_context *ac, if (ar->pright && start + size - 1 >= ar->lright) size -= start + size - ar->lright; + /* + * Trim allocation request for filesystems with artificially small + * groups. + */ + if (size > EXT4_BLOCKS_PER_GROUP(ac->ac_sb)) + size = EXT4_BLOCKS_PER_GROUP(ac->ac_sb); + end = start + size; /* check we don't cross already preallocated blocks */ -- 2.12.0