Hello,
I am facing the same issue on a Btrfs RAID0 with 2 drives:
Label: 'root' uuid: 1e26b203-fc1e-4ebf-9551-451bd34d3ac4
Total devices 2 FS bytes used 36.14GB
devid 1 size 80.43GB used 41.65GB path /dev/sda6
devid 2 size 80.43GB used 41.63GB path /dev/sdb6
Btrfs v0.19-36-g70c6c10-dirty
Tried btrfs-select-super -s 1 /dev/sd[ab]6, but that does not help at all. On both drives, its standard output is identical:
parent transid verify failed on 576901120 wanted 70669 found 70755
btrfs-select-super: disk-io.c:412: find_and_setup_root: Assertion `!(!root->node)' failed.
using SB copy 1, bytenr 67108864
This is the first error message from dmesg:
[ 156.617407] parent transid verify failed on 576901120 wanted 70669 found 70755
[ 156.617504] parent transid verify failed on 576901120 wanted 70669 found 70755
[ 156.635322] btrfs: open_ctree failed
The problem occurred shortly after this issue: http://www.mail-archive.com/linux-btrfs@vger.kernel.org/msg10618.html The machine booted (and worked normally) at least ten times between the error message and the current problem.
The kernel version was 2.6.39.1 when the first BUG message appeared in dmesg. I downgraded to 2.6.38.8 after that and everything seemed to work fine ... up to now.
Any suggestions? ;-) I can always restore the data from another machine with identical installation. But first of all I'd like to understand this problem and know whether it can be dealt with somehow.
Andrej