On Thursday, May 21, 2020 3:56:01 AM EDT Qu Wenruo wrote: > That doesn't sound good. But according to your btrfs check result, your > memory doesn't look good. > There seems to be a memory bit flip. > > A full memtest is highly recommended. > > And since your hardware is not functioning reliable, everything can go > wrong. There was a thunderstorm. The power blinked twice within a few minutes. That could have easily caused the bit flip. > > UUID: 1f5a6f23-a7ef-46c6-92b1-84fc2f684931 > > [1/7] checking root items > > [2/7] checking extents > > incorrect local backref count on 4186230784 root 257 owner 99013 offset > > 5033684992 found 1 wanted 2097153 back 0x5589817e5ef0 > > Here, the 2097153 is 0x200001, it's an obvious bitflip. > > And since it's in extent tree, even write time tree checker can't detect it. > > But that problem is not a big thing, btrfs check --repair can fix it. > > Still, memtest first, only process to try repair after your memory is fixed. "btrfs check" gave me a "device busy" error. (When I booted the M.2, this was caused by the hung mount process, but it happened even when I booted the flash drive. I don't know why.) I couldn't repair it. I had to get a new drive and recover the files to the new drive. Trying to mount the corrupt filesystem consistently hangs. That indicates a bug in mount. How can I send you the corrupt filesystem so that you can debug mount? Pierre -- The Black Garden on the Mountain is not on the Black Mountain.
