diff options
| author | Theodore Ts'o <tytso@mit.edu> | 2011-09-09 18:28:51 -0400 |
|---|---|---|
| committer | Theodore Ts'o <tytso@mit.edu> | 2011-09-09 18:28:51 -0400 |
| commit | 7c2e70879fc0949b4220ee61b7c4553f6976a94d (patch) | |
| tree | 5eea688d4ca50ec27e9cf59144f257e1683cfeb7 | |
| parent | 02fac1297eb3f471a27368271aadd285548297b0 (diff) | |
| download | linux-7c2e70879fc0949b4220ee61b7c4553f6976a94d.tar.bz2 | |
ext4: add ext4-specific kludge to avoid an oops after the disk disappears
The del_gendisk() function uninitializes the disk-specific data
structures, including the bdi structure, without telling anyone
else. Once this happens, any attempt to call mark_buffer_dirty()
(for example, by ext4_commit_super), will cause a kernel OOPS.
Fix this for now until we can fix things in an architecturally correct
way.
Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
| -rw-r--r-- | fs/ext4/super.c | 18 |
1 files changed, 17 insertions, 1 deletions
diff --git a/fs/ext4/super.c b/fs/ext4/super.c index ee2f74a7084d..5dcd0dacc591 100644 --- a/fs/ext4/super.c +++ b/fs/ext4/super.c @@ -414,6 +414,22 @@ static void save_error_info(struct super_block *sb, const char *func, ext4_commit_super(sb, 1); } +/* + * The del_gendisk() function uninitializes the disk-specific data + * structures, including the bdi structure, without telling anyone + * else. Once this happens, any attempt to call mark_buffer_dirty() + * (for example, by ext4_commit_super), will cause a kernel OOPS. + * This is a kludge to prevent these oops until we can put in a proper + * hook in del_gendisk() to inform the VFS and file system layers. + */ +static int block_device_ejected(struct super_block *sb) +{ + struct inode *bd_inode = sb->s_bdev->bd_inode; + struct backing_dev_info *bdi = bd_inode->i_mapping->backing_dev_info; + + return bdi->dev == NULL; +} + /* Deal with the reporting of failure conditions on a filesystem such as * inconsistencies detected or read IO failures. @@ -4072,7 +4088,7 @@ static int ext4_commit_super(struct super_block *sb, int sync) struct buffer_head *sbh = EXT4_SB(sb)->s_sbh; int error = 0; - if (!sbh) + if (!sbh || block_device_ejected(sb)) return error; if (buffer_write_io_error(sbh)) { /* |