ubuntu_kselftests_ftrace kernel panic on noble 6.8 kernel on g1-small instances

[Kevin Becker]

I've found that ubuntu_kselftests_ftrace often runs into a kernel panic during ftrace:test.d--instances--instance-event.tc. This has been often happening since the earliest 6.8 kernels tested on the g1-small instance of gcp, including linux-gcp and linux-gke. It doesn't happen on other instance types.

The following is a typical output:

23572 rsync: [sender] link_stat "/tmp/ubuntu_kselftests_ftrace.sentinel" failed: No such file or directory (2)
23573 rsync error: some files/attrs were not transferred (see previous errors) (code 23) at main.c(1865) [Receiver=3.2.7]
23574 rsync: [Receiver] write error: Broken pipe (32)
23575
23576 sut-test TEST SYSTEM FAILURE DETECTED
23577 A failure of the system under test has been detected.
23578 Please review log files for a potential panic, hang or unexpected reboot
...
23600 sut-scan Kernel panic found in log
23601 [ 814.865948] RDX: 0000000000000000 RSI: 0000000000000000 RDI: ffffffffa83fe180
23602 [ 814.873389] RBP: ffffab7cc09a7ca8 R08: 0000000000000000 R09: ffff8d786fbe31f0
23603 [ 814.880635] R10: 0000000000000000 R11: 0000000000000000 R12: ffff8d78458f0180
23604 [ 814.887891] R13: ffff8d786fbe31f0 R14: ffff8d7844040020 R15: ffff8d7848cef840
23605 [ 814.895146] FS: 00007ce7d92f1740(0000) GS:ffff8d78a9c00000(0000) knlGS:0000000000000000
23606 [ 814.903386] CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
23607 [ 814.909250] CR2: ffffffffa79bebc1 CR3: 0000000006bac004 CR4: 00000000001706f0
23608 [ 814.916502] DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
23609 [ 814.923740] DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
23610 [ 814.930979] Kernel panic - not syncing: Fatal exception
23611 [ 814.936476] Kernel Offset: 0x24e00000 from 0xffffffff81000000 (relocation range: 0xffffffff80000000-0xffffffffbfffffff)
23612 [ 814.968402] Rebooting in 10 seconds..