[LU-9146] Backport patches from upstream to resolve deadlock in xattr

Duplicate — Wed, 16 Jan 2019 20:40:50 +0000

We need backport below patches from upstream to resolve deadlock for i_data_sem.

From a521100231f816f8cdd9c8e77da14ff1e42c2b17 Mon Sep 17 00:00:00 2001
From: Theodore Ts'o <tytso@mit.edu>
Date: Thu, 4 Sep 2014 18:06:25 -0400
Subject: [PATCH] ext4: pass allocation_request struct to
ext4_(alloc,splice)_branch

Instead of initializing the allocation_request structure in
ext4_alloc_branch(), set it up in ext4_ind_map_blocks(), and then pass
it to ext4_alloc_branch() and ext4_splice_branch().

This allows ext4_ind_map_blocks to pass flags in the allocation
request structure without having to add Yet Another argument to
ext4_alloc_branch().

Signed-off-by: Theodore Ts'o <tytso@mit.edu>
Reviewed-by: Jan Kara <jack@suse.cz>

From e3cf5d5d9a86df1c5e413bdd3725c25a16ff854c Mon Sep 17 00:00:00 2001
From: Theodore Ts'o <tytso@mit.edu>
Date: Thu, 4 Sep 2014 18:07:25 -0400
Subject: [PATCH] ext4: prepare to drop EXT4_STATE_DELALLOC_RESERVED

The EXT4_STATE_DELALLOC_RESERVED flag was originally implemented
because it was too hard to make sure the mballoc and get_block flags
could be reliably passed down through all of the codepaths that end up
calling ext4_mb_new_blocks().

Since then, we have mb_flags passed down through most of the code
paths, so getting rid of EXT4_STATE_DELALLOC_RESERVED isn't as tricky
as it used to.

This commit plumbs in the last of what is required, and then adds a
WARN_ON check to make sure we haven't missed anything. If this passes
a full regression test run, we can then drop
EXT4_STATE_DELALLOC_RESERVED.

Signed-off-by: Theodore Ts'o <tytso@mit.edu>
Reviewed-by: Jan Kara <jack@suse.cz>

From 2e81a4eeedcaa66e35f58b81e0755b87057ce392 Mon Sep 17 00:00:00 2001
From: Jan Kara <jack@suse.cz>
Date: Thu, 11 Aug 2016 12:38:55 -0400
Subject: [PATCH] ext4: avoid deadlock when expanding inode size

When we need to move xattrs into external xattr block, we call
ext4_xattr_block_set() from ext4_expand_extra_isize_ea(). That may end
up calling ext4_mark_inode_dirty() again which will recurse back into
the inode expansion code leading to deadlocks.

Protect from recursion using EXT4_STATE_NO_EXPAND inode flag and move
its management into ext4_expand_extra_isize_ea() since its manipulation
is safe there (due to xattr_sem) from possible races with
ext4_xattr_set_handle() which plays with it as well.

CC: stable@vger.kernel.org # 4.4.x
Signed-off-by: Jan Kara <jack@suse.cz>
Signed-off-by: Theodore Ts'o <tytso@mit.edu>

Whamcloud Community JIRA

[LU-9146] Backport patches from upstream to resolve deadlock in xattr