2) stress-ng --class filesystem,io
Compared the stress-ng output and kernel log between original/patched kernels.
No regressions.
Actually, in Bionic the original kernel didn't even finish stress-ng in ~20
hours, while the patched kernel finished it in ~1.5 hours (in line w/ other the
releases.)
Thus it's apparently an improvement.
For documentation purposes, this seems to be due to the 'fiemap'
stressor in the 'filesystem' class, which had defunct processes when I
checked before cancelling the tests:
$ ps axf
...
2659 ? Ss 0:00 tmux new
2661 pts/2 Ss 0:00 \_ -bash
2692 pts/2 S+ 0:00 | \_ /bin/sh ./run-stressng.sh
2743 pts/2 S+ 0:00 | \_ sudo stress-ng --sequential 2
--class filesystem,io -t 2m
2745 pts/2 SL+ 0:00 | \_ stress-ng --sequential 2
--class filesystem io -t 2m
2852 pts/2 D+ 0:00 | \_ stress-ng --sequential 2
--class filesystem io -t 2m
2854 pts/2 D+ 0:01 | | \_ stress-ng
--sequential 2 --class filesystem io -t 2m
2856 pts/2 D+ 0:01 | | \_ stress-ng
--sequential 2 --class filesystem io -t 2m
2859 pts/2 D+ 0:01 | | \_ stress-ng
--sequential 2 --class filesystem io -t 2m
2860 pts/2 D+ 0:01 | | \_ stress-ng
--sequential 2 --class filesystem io -t 2m
2853 pts/2 D+ 0:00 | \_ stress-ng --sequential 2
--class filesystem io -t 2m
2855 pts/2 Z+ 322:29 | \_ [stress-ng-fiema]
<defunct>
2857 pts/2 Z+ 323:55 | \_ [stress-ng-fiema]
<defunct>
2858 pts/2 Z+ 321:50 | \_ [stress-ng-fiema]
<defunct>
2861 pts/2 Z+ 322:51 | \_ [stress-ng-fiema]
<defunct>
11823 pts/4 Ss 0:00 \_ -bash
...
** Bug watch added: Linux Kernel Bug Tracker #202833
https://bugzilla.kernel.org/show_bug.cgi?id=202833
--
You received this bug notification because you are a member of Kernel
Packages, which is subscribed to linux in Ubuntu.
https://bugs.launchpad.net/bugs/1902254
Title:
Bionic: btrfs: kernel BUG at /build/linux-
eTBZpZ/linux-4.15.0/fs/btrfs/ctree.c:3233!
Status in linux package in Ubuntu:
Fix Committed
Status in linux source package in Bionic:
In Progress
Status in linux source package in Focal:
In Progress
Status in linux source package in Groovy:
In Progress
Bug description:
[Impact]
* Users of btrfs started hitting a kernel BUG() (below)
after upgrade from 4.15.0-99.100 to 4.15.0-109.110,
which has 55 btrfs changes.
kernel BUG at /build/linux-eTBZpZ/linux-4.15.0/fs/btrfs/ctree.c:3233!
...
Krnl PSW : 00000000be9cb874 00000000ef3786e8
(btrfs_set_item_key_safe+0x152/0x1c0 [btrfs])
...
[...] Call Trace:
[...] btrfs_set_item_key_safe+0x11c/0x1c0 [btrfs])
[...] __btrfs_drop_extents+0xb5a/0xda8 [btrfs]
[...] btrfs_log_changed_extents+0x35c/0xaf0 [btrfs]
[...] btrfs_log_inode+0x9ee/0x1080 [btrfs]
[...] btrfs_log_inode_parent+0x224/0xa10 [btrfs]
[...] btrfs_log_dentry_safe+0x80/0xa8 [btrfs]
[...] btrfs_sync_file+0x392/0x550 [btrfs]
[...] do_fsync+0x5e/0x90
[...] SyS_fdatasync+0x32/0x48
[...] system_call+0xd8/0x2c8
$ git log --oneline Ubuntu-4.15.0-99.100..Ubuntu-4.15.0-109.110 --
fs/btrfs/ | wc -l
55
* The error happens at random moments, regardless of a
particular activity/load. Workaround is to downgrade.
[Fix]
* This BUG()/function is addressed in patch 4/4 [1] of series
'btrfs: Enhanced runtime defence against fuzzed images' [2],
after issues in the real world, not just crafted fs images:
'one internal report has hit one BUG_ON() with real world fs'
kernel BUG at fs/btrfs/ctree.c:3188!
...
RIP: 0010:btrfs_set_item_key_safe+0x16c/0x180
* The patch/set [3] is applied in v5.10-rc1 and Ubuntu Unstable:
- d16c702fe4f2 btrfs: ctree: check key order before merging tree blocks
- 07cce5cf3b48 btrfs: extent-tree: kill the BUG_ON() in
insert_inline_extent_backref()
- 1c2a07f598d5 btrfs: extent-tree: kill BUG_ON() in __btrfs_free_extent()
- f98b6215d7d1 btrfs: extent_io: do extra check for extent buffer read
write functions
[Test Case]
* There is working synthetic reproducer for this issue,
which is hard to reproduce as reported in commit [4]
that introduces debugging for the issue.
* Regression tests with xfstests and stress-ng shows
no regressions between un/patched kernels.
[Other Info]
* Trivial backports (only refreshing a few context lines)
with 3 more dependency patches on Bionic and 1 on Focal.
And Bionic needed one extra hunk to '#include' a header.
Groovy all apply cleanly.
[1] https://lore.kernel.org/linux-btrfs/20200819063550.62832-5-...@suse.com/
[2] https://lore.kernel.org/linux-btrfs/20200819063550.62832-1-...@suse.com/
[3]
https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/commit/?id=d16c702fe4f274bd77b47d3ab737eadcf24e0b93
[4]
https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/commit/?id=7c15d41016dc886cc011e3854d855e219759ae68
To manage notifications about this bug go to:
https://bugs.launchpad.net/ubuntu/+source/linux/+bug/1902254/+subscriptions
--
Mailing list: https://launchpad.net/~kernel-packages
Post to : kernel-packages@lists.launchpad.net
Unsubscribe : https://launchpad.net/~kernel-packages
More help : https://help.launchpad.net/ListHelp
