[PATCH] ext3/4: don't do orphan processing on readonly devices
If you do something like:
# touch foo
# tail -f foo &
# rm foo
# <take snapshot>
# <mount snapshot>
you'll panic, because ext3/4 tries to do orphan list processing on the
readonly snapshot device, and:
kernel: journal commit I/O error
kernel: Assertion failure in journal_flush_Rsmp_e2f189ce() at journal.c:1356: "!journal->j_checkpoint_transactions"
kernel: Kernel panic: Fatal exception
for a truly readonly underlying device, it's reasonable and necessary
to just skip orphan list processing.
Signed-off-by: Eric Sandeen <sandeen@redhat.com>
Cc: <linux-ext4@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
diff --git a/fs/ext4/super.c b/fs/ext4/super.c
index 2ede7e2..486a641 100644
--- a/fs/ext4/super.c
+++ b/fs/ext4/super.c
@@ -1321,6 +1321,12 @@
return;
}
+ if (bdev_read_only(sb->s_bdev)) {
+ printk(KERN_ERR "EXT4-fs: write access "
+ "unavailable, skipping orphan cleanup.\n");
+ return;
+ }
+
if (EXT4_SB(sb)->s_mount_state & EXT4_ERROR_FS) {
if (es->s_last_orphan)
jbd_debug(1, "Errors on filesystem, "