On Mon, Oct 31, 2016 at 01:27:56PM +0800, Qu Wenruo wrote: > Would you please dump the following bytes? > That's the chunk root tree block on your disk. > > offset: 13500329066496 length: 16384 > offset: 13500330213376 length: 16384 Sorry for asking, am I doing this wrong? myth:~# dd if=/dev/mapper/crypt_bcache0 of=/tmp/dump1 bs=512 count=32 skip=26367830208 dd: reading `/dev/mapper/crypt_bcache0': Invalid argument 0+0 records in 0+0 records out 0 bytes (0 B) copied, 0.000401393 s, 0.0 kB/s
> According to your fsck error output, I assume btrfs-progs fails to read > the first copy of chunk root, and due to a bug, it doesn't continue to > read 2nd copy. > > While kernel continues to read the 2nd copy and everything goes on. Ah, that would make sense. But from what you're saying, I should be able to do recovery by pointing to the 2nd copy of the chunk root, but somehow I haven't typed the right command to do so yet, correct? Should I try another command offset than btrfs check -p --repair --chunk-root 13835462344704 /dev/mapper/crypt_bcache0 ? Or are you saying the btrfs progs bug causes it to fail to even try to read the 2nd copy of the chunk root even though it was given on the command line? Thanks, Marc -- "A mouse is a device used to point at the xterm you want to type in" - A.S.R. Microsoft is to operating systems .... .... what McDonalds is to gourmet cooking Home page: http://marc.merlins.org/ -- To unsubscribe from this list: send the line "unsubscribe linux-btrfs" in the body of a message to majord...@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html