diff options
author | Ye Bin <yebin10@huawei.com> | 2021-05-06 22:10:42 +0800 |
---|---|---|
committer | Theodore Ts'o <tytso@mit.edu> | 2021-06-06 10:09:55 -0400 |
commit | 082cd4ec240b8734a82a89ffb890216ac98fec68 (patch) | |
tree | 609a23cf2e4c09948b97b285c3dd0b8011b82eb8 | |
parent | b45f189a19b38e01676628db79cd3eeb1333516e (diff) |
ext4: fix bug on in ext4_es_cache_extent as ext4_split_extent_at failed
We got follow bug_on when run fsstress with injecting IO fault:
[130747.323114] kernel BUG at fs/ext4/extents_status.c:762!
[130747.323117] Internal error: Oops - BUG: 0 [#1] SMP
......
[130747.334329] Call trace:
[130747.334553] ext4_es_cache_extent+0x150/0x168 [ext4]
[130747.334975] ext4_cache_extents+0x64/0xe8 [ext4]
[130747.335368] ext4_find_extent+0x300/0x330 [ext4]
[130747.335759] ext4_ext_map_blocks+0x74/0x1178 [ext4]
[130747.336179] ext4_map_blocks+0x2f4/0x5f0 [ext4]
[130747.336567] ext4_mpage_readpages+0x4a8/0x7a8 [ext4]
[130747.336995] ext4_readpage+0x54/0x100 [ext4]
[130747.337359] generic_file_buffered_read+0x410/0xae8
[130747.337767] generic_file_read_iter+0x114/0x190
[130747.338152] ext4_file_read_iter+0x5c/0x140 [ext4]
[130747.338556] __vfs_read+0x11c/0x188
[130747.338851] vfs_read+0x94/0x150
[130747.339110] ksys_read+0x74/0xf0
This patch's modification is according to Jan Kara's suggestion in:
https://patchwork.ozlabs.org/project/linux-ext4/patch/20210428085158.3728201-1-yebin10@huawei.com/
"I see. Now I understand your patch. Honestly, seeing how fragile is trying
to fix extent tree after split has failed in the middle, I would probably
go even further and make sure we fix the tree properly in case of ENOSPC
and EDQUOT (those are easily user triggerable). Anything else indicates a
HW problem or fs corruption so I'd rather leave the extent tree as is and
don't try to fix it (which also means we will not create overlapping
extents)."
Cc: stable@kernel.org
Signed-off-by: Ye Bin <yebin10@huawei.com>
Reviewed-by: Jan Kara <jack@suse.cz>
Link: https://lore.kernel.org/r/20210506141042.3298679-1-yebin10@huawei.com
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
-rw-r--r-- | fs/ext4/extents.c | 43 |
1 files changed, 23 insertions, 20 deletions
diff --git a/fs/ext4/extents.c b/fs/ext4/extents.c index 77c84d6f1af6..cbf37b2cf871 100644 --- a/fs/ext4/extents.c +++ b/fs/ext4/extents.c @@ -3206,7 +3206,10 @@ static int ext4_split_extent_at(handle_t *handle, ext4_ext_mark_unwritten(ex2); err = ext4_ext_insert_extent(handle, inode, ppath, &newex, flags); - if (err == -ENOSPC && (EXT4_EXT_MAY_ZEROOUT & split_flag)) { + if (err != -ENOSPC && err != -EDQUOT) + goto out; + + if (EXT4_EXT_MAY_ZEROOUT & split_flag) { if (split_flag & (EXT4_EXT_DATA_VALID1|EXT4_EXT_DATA_VALID2)) { if (split_flag & EXT4_EXT_DATA_VALID1) { err = ext4_ext_zeroout(inode, ex2); @@ -3232,25 +3235,22 @@ static int ext4_split_extent_at(handle_t *handle, ext4_ext_pblock(&orig_ex)); } - if (err) - goto fix_extent_len; - /* update the extent length and mark as initialized */ - ex->ee_len = cpu_to_le16(ee_len); - ext4_ext_try_to_merge(handle, inode, path, ex); - err = ext4_ext_dirty(handle, inode, path + path->p_depth); - if (err) - goto fix_extent_len; - - /* update extent status tree */ - err = ext4_zeroout_es(inode, &zero_ex); - - goto out; - } else if (err) - goto fix_extent_len; - -out: - ext4_ext_show_leaf(inode, path); - return err; + if (!err) { + /* update the extent length and mark as initialized */ + ex->ee_len = cpu_to_le16(ee_len); + ext4_ext_try_to_merge(handle, inode, path, ex); + err = ext4_ext_dirty(handle, inode, path + path->p_depth); + if (!err) + /* update extent status tree */ + err = ext4_zeroout_es(inode, &zero_ex); + /* If we failed at this point, we don't know in which + * state the extent tree exactly is so don't try to fix + * length of the original extent as it may do even more + * damage. + */ + goto out; + } + } fix_extent_len: ex->ee_len = orig_ex.ee_len; @@ -3260,6 +3260,9 @@ fix_extent_len: */ ext4_ext_dirty(handle, inode, path + path->p_depth); return err; +out: + ext4_ext_show_leaf(inode, path); + return err; } /* |