Performing verification for Bionic I started a fresh VM with 4.15.0-206-generic from -updates. I attached 2x virtio disks of 3gb each, for scratch disks. I ran btrfs/154 with the following results: # ./check btrfs/154 FSTYP -- btrfs PLATFORM -- Linux/x86_64 bionic-xfs 4.15.0-206-generic #217-Ubuntu SMP Fri Feb 3 19:10:13 UTC 2023 MKFS_OPTIONS -- /dev/vdd MOUNT_OPTIONS -- /dev/vdd /scratch btrfs/154 4s ... _check_dmesg: something found in dmesg (see /home/ubuntu/xfstests-dev/results//btrfs/154.dmesg) - output mismatch (see /home/ubuntu/xfstests-dev/results//btrfs/154.out.bad) --- tests/btrfs/154.out 2023-01-28 02:53:03.566450703 +0000 +++ /home/ubuntu/xfstests-dev/results//btrfs/154.out.bad 2023-03-14 04:46:12.824848412 +0000 @@ -1,2 +1,6 @@ QA output created by 154 +Traceback (most recent call last): + File "/home/ubuntu/xfstests-dev/src/btrfs_crc32c_forged_name.py", line 99, in + os.rename(srcpath, dstpath) +OSError: [Errno 75] Value too large for defined data type: '/scratch/309' -> b'/scratch/ec73\xb4\xd3?\xc4249e4acad9bcfc483738ce72c1da9a5e0dcc098e3103a2e00d8e05fe6a463df2c472d5df948dc08e6aaf48cdff3c41de690ce50cd88be6cdea40e616db44152df10f8dfe36a5de62550b277db85c01455dde98b189b68' Silence is golden ... (Run 'diff -u /home/ubuntu/xfstests-dev/tests/btrfs/154.out /home/ubuntu/xfstests-dev/results//btrfs/154.out.bad' to see the entire diff) Ran: btrfs/154 Failures: btrfs/154 Failed 1 of 1 tests [ 69.108117] BTRFS: device fsid 032cd7d2-e729-4a6a-aa6d-95141191525a devid 1 transid 5 /dev/vdc [ 78.693183] BTRFS info (device vdc): disk space caching is enabled [ 78.693184] BTRFS info (device vdc): has skinny extents [ 78.693185] BTRFS info (device vdc): flagging fs with big metadata feature [ 78.695928] BTRFS info (device vdc): creating UUID tree [ 78.828837] BTRFS: device fsid 053e2dfb-59fb-45ab-8a69-08262d44d669 devid 1 transid 5 /dev/vdd [ 78.840701] BTRFS info (device vdd): disk space caching is enabled [ 78.840703] BTRFS info (device vdd): has skinny extents [ 78.840704] BTRFS info (device vdd): flagging fs with big metadata feature [ 78.843953] BTRFS info (device vdd): creating UUID tree [ 79.053524] BTRFS info (device vdc): disk space caching is enabled [ 79.053526] BTRFS info (device vdc): has skinny extents [ 79.104532] run fstests btrfs/154 at 2023-03-14 04:46:08 [ 79.230124] BTRFS: device fsid af57acbb-7a45-46e8-969f-4cb3ce52e29e devid 1 transid 5 /dev/vdd [ 79.235760] BTRFS info (device vdd): disk space caching is enabled [ 79.235761] BTRFS info (device vdd): has skinny extents [ 79.235761] BTRFS info (device vdd): flagging fs with big metadata feature [ 79.239893] BTRFS info (device vdd): creating UUID tree [ 82.714095] ------------[ cut here ]------------ [ 82.714098] BTRFS: Transaction aborted (error -75) [ 82.714180] WARNING: CPU: 2 PID: 1883 at /build/linux-sIqTXt/linux-4.15.0/fs/btrfs/inode.c:10217 btrfs_rename+0xcf1/0xdf0 [btrfs] [ 82.714210] CPU: 2 PID: 1883 Comm: python3 Not tainted 4.15.0-206-generic #217-Ubuntu [ 82.714212] Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS 1.16.0-debian-1.16.0-4 04/01/2014 [ 82.714234] RIP: 0010:btrfs_rename+0xcf1/0xdf0 [btrfs] [ 82.714235] RSP: 0018:ffffaf86c1adfd20 EFLAGS: 00010282 [ 82.714238] RAX: 0000000000000000 RBX: ffff96e6f7bac118 RCX: 0000000000000006 [ 82.714239] RDX: 0000000000000007 RSI: 0000000000000096 RDI: ffff96e6ffd1b4d0 [ 82.714240] RBP: ffffaf86c1adfdc0 R08: 00000000000002d9 R09: 0000000000000004 [ 82.714241] R10: 0000000000000000 R11: 0000000000000001 R12: 0000000000000236 [ 82.714242] R13: ffff96e6f6842618 R14: ffff96e6f7b78cc0 R15: ffff96e6f7bac118 [ 82.714245] FS: 00007fbf05988740(0000) GS:ffff96e6ffd00000(0000) knlGS:0000000000000000 [ 82.714246] CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 [ 82.714248] CR2: 00007fbf058ef4c8 CR3: 0000000175166005 CR4: 0000000000760ee0 [ 82.714254] PKRU: 55555554 [ 82.714255] Call Trace: [ 82.714277] btrfs_rename2+0x1d/0x30 [btrfs] [ 82.714283] vfs_rename+0x46e/0x960 [ 82.714287] SyS_rename+0x362/0x3c0 [ 82.714293] do_syscall_64+0x73/0x130 [ 82.714297] entry_SYSCALL_64_after_hwframe+0x59/0xbe [ 82.714299] RIP: 0033:0x7fbf053f8ce7 [ 82.714300] RSP: 002b:00007ffdb2ba86d8 EFLAGS: 00000246 ORIG_RAX: 0000000000000052 [ 82.714302] RAX: ffffffffffffffda RBX: 00007ffdb2ba8790 RCX: 00007fbf053f8ce7 [ 82.714303] RDX: 00000000ffffffff RSI: 00007fbf044872f0 RDI: 00007fbf057dafb0 [ 82.714304] RBP: 00000000ffffff00 R08: 0000000000000000 R09: 0000000000713557 [ 82.714306] R10: 0000000000000000 R11: 0000000000000246 R12: 00007ffdb2ba8740 [ 82.714307] R13: 00000000ffffff9c R14: 00000000ffffff9c R15: 0000000001365da0 [ 82.714309] Code: 0f ba a8 d0 cd 00 00 02 72 2b 41 83 f8 fb 0f 84 d9 00 00 00 44 89 c6 48 c7 c7 68 83 43 c0 44 89 55 80 44 89 45 98 e8 6f 1c 0e f5 <0f> 0b 44 8b 45 98 44 8b 55 80 44 89 55 80 44 89 c1 44 89 45 98 [ 82.714329] ---[ end trace 4d63dbb061789135 ]--- [ 82.714333] BTRFS: error (device vdd) in btrfs_rename:10217: errno=-75 unknown [ 82.715832] BTRFS info (device vdd): forced readonly [ 82.990842] BTRFS info (device vdd): disk space caching is enabled [ 82.990845] BTRFS info (device vdd): has skinny extents The test fails on the kernel in -updates, as expected. I then enabled -proposed, and installed 4.15.0-207-generic. Re-running the test on a clean btrfs filesystem: # ./check btrfs/154 FSTYP -- btrfs PLATFORM -- Linux/x86_64 bionic-xfs 4.15.0-207-generic #218-Ubuntu SMP Thu Feb 23 23:36:05 UTC 2023 MKFS_OPTIONS -- /dev/vdd MOUNT_OPTIONS -- /dev/vdd /scratch btrfs/154 4s ... 4s Ran: btrfs/154 Passed all 1 tests The test passes and there is no output in dmesg. The kernel in -proposed fixes the issue and I am happy to mark it as verified for Bionic.