From: Daeho Jeong Subject: [PATCH] ext4: fix xfstest generic/269 double revoked buffer bug Date: Thu, 15 Oct 2015 09:23:18 +0900 Message-ID: <1444868598-16188-1-git-send-email-daeho.jeong@samsung.com> Cc: Daeho Jeong To: tytso@mit.edu, linux-ext4@vger.kernel.org Return-path: Received: from mailout2.samsung.com ([203.254.224.25]:54483 "EHLO mailout2.samsung.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1753098AbbJOAXH (ORCPT ); Wed, 14 Oct 2015 20:23:07 -0400 Received: from epcpsbgr1.samsung.com (u141.gpu120.samsung.co.kr [203.254.230.141]) by mailout2.samsung.com (Oracle Communications Messaging Server 7.0.5.31.0 64bit (built May 5 2014)) with ESMTP id <0NW8002WRJQH3200@mailout2.samsung.com> for linux-ext4@vger.kernel.org; Thu, 15 Oct 2015 09:23:05 +0900 (KST) Sender: linux-ext4-owner@vger.kernel.org List-ID: When you repeatly execute xfstest generic/269 with bigalloc_1k option enabled using the below command: "./kvm-xfstests -c bigalloc_1k -m nodelalloc -C 1000 generic/269" you can easily see the below bug message. "JBD2 unexpected failure: jbd2_journal_revoke: !buffer_revoked(bh);" This means that an already revoked buffer is erroneously revoked again and it is caused by doing revoke for the buffer at the wrong position in ext4_free_blocks(). We need to re-position the buffer revoke procedure for an unspecified buffer after checking the cluster boundary for bigalloc option. If not, some part of the cluster can be doubly revoked. Signed-off-by: Daeho Jeong --- fs/ext4/mballoc.c | 33 ++++++++++++++++++--------------- 1 file changed, 18 insertions(+), 15 deletions(-) diff --git a/fs/ext4/mballoc.c b/fs/ext4/mballoc.c index 34b610e..abea276 100644 --- a/fs/ext4/mballoc.c +++ b/fs/ext4/mballoc.c @@ -4682,22 +4682,11 @@ void ext4_free_blocks(handle_t *handle, struct inode *inode, ext4_debug("freeing block %llu\n", block); trace_ext4_free_blocks(inode, block, count, flags); - if (flags & EXT4_FREE_BLOCKS_FORGET) { - struct buffer_head *tbh = bh; - int i; - - BUG_ON(bh && (count > 1)); + if (bh && (flags & EXT4_FREE_BLOCKS_FORGET)) { + BUG_ON(count > 1); - for (i = 0; i < count; i++) { - cond_resched(); - if (!bh) - tbh = sb_find_get_block(inode->i_sb, - block + i); - if (!tbh) - continue; - ext4_forget(handle, flags & EXT4_FREE_BLOCKS_METADATA, - inode, tbh, block + i); - } + ext4_forget(handle, flags & EXT4_FREE_BLOCKS_METADATA, + inode, bh, block); } /* @@ -4742,6 +4731,20 @@ void ext4_free_blocks(handle_t *handle, struct inode *inode, count += sbi->s_cluster_ratio - overflow; } + if (!bh && (flags & EXT4_FREE_BLOCKS_FORGET)) { + int i; + + for (i = 0; i < count; i++) { + cond_resched(); + bh = sb_find_get_block(inode->i_sb, + block + i); + if (!bh) + continue; + ext4_forget(handle, flags & EXT4_FREE_BLOCKS_METADATA, + inode, bh, block + i); + } + } + do_more: overflow = 0; ext4_get_group_no_and_offset(sb, block, &block_group, &bit); -- 1.7.9.5