Please close the bug.
I don't see it anymore,
and maybe it was fixed here:
https://github.com/kdave/btrfs-progs/issues/225
W dniu 12.10.2025 o 03:41, Nicholas D Steeves pisze:
Hi Leszek,
Sorry it took me so long to follow-up on this bug.
Leszek Dubiel <[email protected]> writes:
I made further tests.
This system runs since 2018-02, so maybe it is spoiled from some bugs in
debian stretch (ver 9).
For i386 (i686), maybe! If I remember correctly there are still 32bit
bugs. Amd64/intel64 has been good since linux-4.4, and I have two
heavily used systems that have been fine since then. But before for
that? Ouf...
Leszek Dubiel <[email protected]> writes:
Another test with "--repair" make BUG_ON:
time btrfs check --mode=lowmem --progress --repair /dev/sda1
enabling repair mode
WARNING: low-memory mode repair support is only partial
Opening filesystem to check...
Checking filesystem on /dev/sda1
UUID: 666a7089-d716-44ff-8081-56b969b58eff
[1/7] checking root items (0:04:08 elapsed,
10279825 items checked)
Fixed 0 roots.
ERROR: extent[1198869807104 16384] backref lost (owner: 2, level: 0)
root 2s checked)
ERROR: fail to allocate new chunk No space left on device
Do you remember if you ever balanced metadata?
Try to exclude all metadata blcoks and extents, it may be slowd, 81140
items checked)
Added an extent item [1198869807104 16384] (2:16:04 elapsed, 81140
items checked)
Added one tree block ref start 1198869807104 root 26:05 elapsed, 81140
items checked)
ERROR: extent[81379328 16384] backref lost (owner: 2, level: 0) root 2
items checked)
Added an extent item [81379328 16384]
transaction.c:168: btrfs_commit_transaction: BUG_ON `ret` triggered,
value -17
btrfs(+0x3c0ad)[0x5320ad]
btrfs(btrfs_commit_transaction+0x68)[0x5324bb]
btrfs(+0x78c24)[0x56ec24]
btrfs(check_chunks_and_extents_lowmem+0x198)[0x572060]
btrfs(cmd_check+0x16e2)[0x554da5]
btrfs(main+0x22c)[0x502edc]
/lib/i386-linux-gnu/libc.so.6(__libc_start_main+0xf1)[0xb7badb41]
btrfs(_start+0x31)[0x502f21]
Przerwane
real 140m42,553s
user 6m14,394s
sys 2m21,156s
I guess the upside is it failed faster this time? (2h20min vs 3days)
The lowmem mode was practically brand new back then, and I wonder how
useful it is to keep this bug open. Do you remember if you contacted
upstream linux-btrfs? Often they'll expand he scope of btrfs-check to
accommodate new cases.
Cheers!
Nicholas
