Hello folks! Thanks for all the work you have put in developing btrfs! My problems: I happen to have a VMware virtual machine which started with one virtual disk for "playing" with btrfs. Later on I got some more space, so then the "btrfs disks" bacame two. I took the opportunity to try out the JBOD function of btrfs, and came out impressed! The problem is that the VM host machine does not have an uninterruptible power supply, so it died a few times "without warning"... Was NOT a problem until now, when I tried to delete some files, but instead got a kernel panic: [ 51.687879] btrfs unable to find ref byte nr 219711594496 parent 0 root 5 owner 84016 offset 716963840 [ 51.688757] BUG: unable to handle kernel NULL pointer dereference at (null) [ 51.688930] IP: [<c11cfb5f>] map_private_extent_buffer+0xf/0x110 [ 51.689053] *pde = 00000000 [ 51.689155] Opps: 0000 [#1] SMP and so on - see the details in the atteched .png image as I got a screenshot of the trace. And this is on Linus'' latest v3.3-rc7 x86 kernel. The distro is crux. Here is what my /etc/fstab looks like: # # /etc/fstab: static file system information # # <file system> <dir> <type> <options> <dump> <pass> /dev/sda2 / xfs relatime,delaylog 0 0 devpts /dev/pts devpts defaults 0 0 none /sys sysfs defaults 0 0 none /proc proc defaults 0 0 /dev/sda1 /boot xfs relatime,delaylog 0 0 /dev/sdb /mnt/scsi1 btrfs device=/dev/sdb,device=/dev/sdc,relatime,compress=lzo,autodefrag 0 0 These "btrfs for a spin" drives hold mostly garbage data, and the files that trigger the oops can stay as long as it takes, but if there is anything I can do to help it - please, let me know. I want to be able to delete them. P.S. Please, CC me as I''m not subscribed to the list, not yet, anyway...