Hi David,
On 01/07/2014 12:30 AM, David Sterba wrote:
On Mon, Jan 06, 2014 at 05:25:06PM +0800, Wang Shilong wrote:
Steps to reproduce:
# mkfs.btrfs -f /dev/sda8
# mount /dev/sda8 /mnt
# btrfs sub snapshot -r /mnt /mnt/snap1
# btrfs sub snapshot -r /mnt /mnt/snap2
# btrfs send /mnt/snap2 -p /mnt/snap1
As @send_root will also add into clone_sources, and we should
take care not to decrease its count twice.
Yes, send_root is appended to the clone_roots but the
clone_sources_to_rollback does not track this, it's not updated after
it's added in
sctx->clone_roots[sctx->clone_roots_cnt++].root = sctx->send_root;
so send->root->send_in_progress is not modified in the loop that
decrements all clone_root's counters again.
I don't see the warning that should catch negative values of the counter
in btrfs_root_dec_send_in_progress. Am I missing something?
You are right here, but problem still exist.
The problem is that we will sort clone sources before we decrease count,
When sorting clone counts, we include send_root, and it will push to the
first
place.....and when we try to free send_root count, it will be decreased
twice.
Hope i am not wrong this time!
Thanks Daivd to force me dig more!
david
--
To unsubscribe from this list: send the line "unsubscribe linux-btrfs" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at http://vger.kernel.org/majordomo-info.html
--
To unsubscribe from this list: send the line "unsubscribe linux-btrfs" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at http://vger.kernel.org/majordomo-info.html
