I am running Arch Linux on a system with full disk encryption and the
storage is a Samsung 950 Pro NVMe drive (512 GB). The computer is a
couple months old. No bad behavior until now. (I'm only using 21 GB of
the 512 space on the disk.)
btrfs-progs v4.5.1
Today I was using my system normally and browsing the web. Firefox
stopped responding suddenly and for no apparent reason. Then (KDE)
Plasma stopped responding. I could not log out of KDE.
I killed my user session (pkill -u me), then I tired to startx. At
that point I noticed my root filesystem was read-only.
As a first step, I rebooted. That didn't help anything. I tried
rebooting several more times -- no change.
The root filesystem (btrfs) would not mount. (See error below.) I
booted into a LiveUSB environment and ran this command:
cryptsetup open --type luks /dev/xxx cryptroot
It opens. Then I ran:
mount -t btrfs -o
noatime,nodiratime,ssd,compress=lzo,defaults,space_cache,subvolid=257
/dev/mapper/cryptroot /mnt
The error message is shown here:
[ 2300.967048] BTRFS info (device dm-0): use ssd allocation scheme
[ 2300.967058] BTRFS info (device dm-0): use lzo compression
[ 2300.967066] BTRFS info (device dm-0): disk space caching is enabled
[ 2300.967069] BTRFS: has skinny extents
[ 2300.995393] BTRFS: error (device dm-0) in
btrfs_replay_log:2413: errno=-22 unknown (Failed to recover log tree)
[ 2300.997617] BTRFS info (device dm-0): delayed_refs has NO entry
[ 2300.997673] BTRFS error (device dm-0): cleaner transaction
attach returned -30
[ 2301.035405] BTRFS: open_ctree failed
It is exactly the same error I saw when trying to boot normally as
mentioned above.
Based on these two links:
> https://btrfs.wiki.kernel.org/index.php/Problem_FAQ
> https://btrfs.wiki.kernel.org/index.php/Btrfs-zero-log
I decided to take a chance on running this command:
btrfs rescue zero-log
That worked and I can mount the filesystem.
I ran btrfs check --repair. Here is the output:
root@broken / # umount /mnt
root@broken / # btrfs check --repair /dev/mapper/cryptroot
enabling repair mode
Checking filesystem on /dev/mapper/cryptroot
checking extents
bad metadata [292414476288, 292414492672) crossing stripe boundary
bad metadata [292414541824, 292414558208) crossing stripe boundary
bad metadata [292414672896, 292414689280) crossing stripe boundary
bad metadata [292414869504, 292414885888) crossing stripe boundary
bad metadata [292415000576, 292415016960) crossing stripe boundary
bad metadata [292415066112, 292415082496) crossing stripe boundary
bad metadata [292415131648, 292415148032) crossing stripe boundary
bad metadata [292415262720, 292415279104) crossing stripe boundary
bad metadata [292415328256, 292415344640) crossing stripe boundary
bad metadata [292415393792, 292415410176) crossing stripe boundary
repaired damaged extent references
Fixed 0 roots.
checking free space cache
cache and super generation don't match, space cache will be invalidated
checking fs roots
checking csums
checking root refs
checking quota groups
Ignoring qgroup relation key 258
Ignoring qgroup relation key 263
Ignoring qgroup relation key 71776119061217538
Ignoring qgroup relation key 71776119061217543
Counts for qgroup id: 257 are different
our: referenced 10412273664 referenced compressed 10412273664
disk: referenced 10411311104 referenced compressed 10411311104
diff: referenced 962560 referenced compressed 962560
our: exclusive 10412273664 exclusive compressed 10412273664
disk: exclusive 10412273664 exclusive compressed 10412273664
found 21570773057 bytes used err is 0
total csum bytes: 19563456
total tree bytes: 403767296
total fs tree bytes: 349667328
total extent tree bytes: 27328512
btree space waste bytes: 66313360
file data blocks allocated: 39882014720
referenced 28043988992
extent buffer leak: start 20987904 len 16384
extent buffer leak: start 292688068608 len 16384
extent buffer leak: start 60915712 len 16384
extent buffer leak: start 29569581056 len 16384
extent buffer leak: start 29569597440 len 16384
extent buffer leak: start 292412063744 len 16384
extent buffer leak: start 292405870592 len 16384
extent buffer leak: start 292405936128 len 16384
extent buffer leak: start 292413964288 len 16384
Then I check dmesg and I see this error information:
[ 4925.562422] BTRFS info (device dm-0): use ssd allocation scheme
[ 4925.562432] BTRFS info (device dm-0): use lzo compression
[ 4925.562440] BTRFS info (device dm-0): disk space caching is enabled
[ 4925.562444] BTRFS: has skinny extents
[ 4925.578705] BTRFS error (device dm-0): qgroup generation
mismatch, marked as inconsistent
[ 4925.584033] BTRFS: checking UUID tree
What should I do next? I'm a simple user.
I already ran memtest86+ overnight using 8 CPU cores in parallel (so
it was a very thorough memory test). There were 0 RAM errors.
I previously used btrfs since 2012 with no issues. I am concerned
about the present issue because I do not understand the cause.
--
To unsubscribe from this list: send the line "unsubscribe linux-btrfs" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at http://vger.kernel.org/majordomo-info.html