@@ -3963,6 +3963,10 @@ int btrfs_resume_balance_async(struct btrfs_fs_info *fs_info)
return 0;
}
+ spin_lock(&fs_info->balance_lock);
+ fs_info->balance_ctl->flags |= BTRFS_BALANCE_RESUME;
+ spin_unlock(&fs_info->balance_lock);
+
tsk = kthread_run(balance_kthread, fs_info, "btrfs-balance");
return PTR_ERR_OR_ZERO(tsk);
}
@@ -4004,7 +4008,6 @@ int btrfs_recover_balance(struct btrfs_fs_info *fs_info)
bctl->fs_info = fs_info;
bctl->flags = btrfs_balance_flags(leaf, item);
- bctl->flags |= BTRFS_BALANCE_RESUME;
btrfs_balance_data(leaf, item, &disk_bargs);
btrfs_disk_balance_args_to_cpu(&bctl->data, &disk_bargs);
We set the BTRFS_BALANCE_RESUME flag in the btrfs_recover_balance(), which is not called during the remount. So when resuming from the paused balance we hit BUG. kernel: kernel BUG at fs/btrfs/volumes.c:3890! :: kernel: balance_kthread+0x51/0x60 [btrfs] kernel: kthread+0x111/0x130 :: kernel: RIP: btrfs_balance+0x12e1/0x1570 [btrfs] RSP: ffffba7d0090bde8 Reproducer: On a mounted BTRFS. btrfs balance start --full-balance /btrfs btrfs balance pause /btrfs mount -o remount,ro /dev/sdb /btrfs mount -o remount,rw /dev/sdb /btrfs To fix this set the BTRFS_BALANCE_RESUME flag in btrfs_resume_balance_async() instead of btrfs_recover_balance(). Signed-off-by: Anand Jain <anand.jain@oracle.com> --- fs/btrfs/volumes.c | 5 ++++- 1 file changed, 4 insertions(+), 1 deletion(-)