I hope "Reply All" is the right option here. Again, first time interacting with a mailing list. Google said that was what to do.
I have found no I/O errors in dmesg -- at least, none mentioning 'I/O', 'IO', or anything triggered by mount besides BTRFS's complaints. $ sudo btrfs rescue chunk -v /dev/sda4 (See https://pastebin.com/YaRHuKeT -- the output hasn't visibly changed since I tried this around a week ago, but this output is recent) $ man btrfs | grep show-super -A1 btrfs-show-super moved to btrfs inspect-internal dump-super $ sudo btrfs inspect-internal dump-super -fa /dev/sda4 (See https://pastebin.com/DbABqXGQ) $ sudo btrfs-find-root -o 5 /dev/sda4 (See https://zerobin.net/?496ed00aed01ab0c#Kvp+FqrF6mfqQLZvUYJ1ODWYIzGayJbdyuMXc9RTauA= -- Pastebin wouldn't let me paste that much) I hope the way I'm organizing the output is OK. On Thu, Aug 17, 2017 at 6:42 PM, Qu Wenruo <quwenruo.bt...@gmx.com> wrote: > > > On 2017年08月18日 00:53, Chris Murphy wrote: >> >> Readding Btrfslist, and adding Qu: >> >> >> On Thu, Aug 17, 2017 at 12:48 AM, Zirconium Hacker <jared.e...@gmail.com> >> wrote: >>> >>> Oh, sorry, I guess the output of the command I ran wasn't clear -- it >>> was collecting the output of running the debug command on all 1,084 >>> and showing that it was the same. Here's specifically what you asked >>> for: >>> >>> $ sudo btrfs-debug-tree -b 61809344512 /dev/sda4 >>> btrfs-progs v4.12 >>> bytenr mismatch, want=61809344512, have=0 >>> Couldn't read tree root >>> ERROR: unable to open /dev/sda4 >>> $ sudo btrfs-debug-tree -b 1085440000 /dev/sda4 >>> btrfs-progs v4.12 >>> bytenr mismatch, want=61809344512, have=0 > > > This means either chunk root is corrupted, or system chunk array in > superblock is corrupted. > Bytenr mismatch is normally impossible for normal operation. > > BTW are you using discard mount option? Sometimes it can cause problem. > > And please also paste the following output: > > # btrfs-show-super -fa /dev/sda4 > # btrfs-find-root -o 5 /dev/sda4 > > The first is to output the full backup roots and current chunk root for us > to debug. > The second one will try to iterate your whole disk to find a valid but old > chunk root. > If we could find one (even a little old), it may make it possible to mount > the fs. > > Thanks, > Qu > >>> Couldn't read tree root >>> ERROR: unable to open /dev/sda4 >>> >>> I'm using GMail, and it's confusing me by trimming off quotes and >>> stuff, so sorry if I miss something. >>> >> >> OK well now we're in the bad part of Btrfs repair where the error >> messages don't help. > It's one thing for it to complain about >> 1085440000 being invalid, because by now it might have been >> overwritten, but to say it wants some other root that we already know >> it can't read, and then fail reading that root is not helpful >> information. >> Maybe Qu has an idea. But it does sound like something really >> catastrophic happened to blow away all of the backup root trees. >> >> Going back to your first email, -o ro,usebackuproot failed with a >> chunk tree error. I wonder if 'rescue chunk' might help. >> >> Try 'btrfs rescue chunk -v' and see what you get. >> >> > -- 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
