3.18-stable review patch. If anyone has any objections, please let me know.
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From: Theodore Ts'o tytso@mit.edu
commit 5012284700775a4e6e3fbe7eac4c543c4874b559 upstream.
Commit 8844618d8aa7: "ext4: only look at the bg_flags field if it is valid" will complain if block group zero does not have the EXT4_BG_INODE_ZEROED flag set. Unfortunately, this is not correct, since a freshly created file system has this flag cleared. It gets almost immediately after the file system is mounted read-write --- but the following somewhat unlikely sequence will end up triggering a false positive report of a corrupted file system:
mkfs.ext4 /dev/vdc mount -o ro /dev/vdc /vdc mount -o remount,rw /dev/vdc
Instead, when initializing the inode table for block group zero, test to make sure that itable_unused count is not too large, since that is the case that will result in some or all of the reserved inodes getting cleared.
This fixes the failures reported by Eric Whiteney when running generic/230 and generic/231 in the the nojournal test case.
Fixes: 8844618d8aa7 ("ext4: only look at the bg_flags field if it is valid") Reported-by: Eric Whitney enwlinux@gmail.com Signed-off-by: Theodore Ts'o tytso@mit.edu [bwh: Backported to 3.16: adjust context] Signed-off-by: Ben Hutchings ben@decadent.org.uk Signed-off-by: Greg Hackmann ghackmann@google.com Signed-off-by: Greg Kroah-Hartman gregkh@linuxfoundation.org --- fs/ext4/ialloc.c | 5 ++++- fs/ext4/super.c | 8 +------- 2 files changed, 5 insertions(+), 8 deletions(-)
--- a/fs/ext4/ialloc.c +++ b/fs/ext4/ialloc.c @@ -1253,7 +1253,10 @@ int ext4_init_inode_table(struct super_b ext4_itable_unused_count(sb, gdp)), sbi->s_inodes_per_block);
- if ((used_blks < 0) || (used_blks > sbi->s_itb_per_group)) { + if ((used_blks < 0) || (used_blks > sbi->s_itb_per_group) || + ((group == 0) && ((EXT4_INODES_PER_GROUP(sb) - + ext4_itable_unused_count(sb, gdp)) < + EXT4_FIRST_INO(sb)))) { ext4_error(sb, "Something is wrong with group %u: " "used itable blocks: %d; " "itable unused count: %u", --- a/fs/ext4/super.c +++ b/fs/ext4/super.c @@ -3140,14 +3140,8 @@ static ext4_group_t ext4_has_uninit_itab if (!gdp) continue;
- if (gdp->bg_flags & cpu_to_le16(EXT4_BG_INODE_ZEROED)) - continue; - if (group != 0) + if (!(gdp->bg_flags & cpu_to_le16(EXT4_BG_INODE_ZEROED))) break; - ext4_error(sb, "Inode table for bg 0 marked as " - "needing zeroing"); - if (sb->s_flags & MS_RDONLY) - return ngroups; }
return group;