Thanks for picking this up. Before the apport-collect data arrives, I need to correct my report, because it matters for triage.
The "Ruled out: host problems: no host errors" line in my description is WRONG. I've since found that the Windows host (i9-14900K) itself shows hardware instability: - 13 x WHEA Event 19 "Corrected Machine Check / Processor Core / Internal parity error" between 2026-08-18 and 2026-10-03, concentrated on APIC IDs 41 (9x), 33 (3x) and 32 (1x) - about 18 host bugchecks since 2026-09-06: 0x20001 HYPERVISOR_ERROR (8x), 0x50, 0x1E, 0x3B, plus resets with no bugcheck - the host runs BIOS defaults (Intel Default Settings), microcode 0x133, XMP off. Intel's IPDT passes, but these symptoms fit 13th/14th-gen Vmin-shift degradation, and I'm pursuing an RMA. So this could be a corrupted pointer from flaky hardware, not a kernel bug. Points that still suggest a real 7.0 regression: - every one of the guest crashes hits the same place: path_is_under() via complete_walk() on plain openat(). In v7.0, complete_walk() only calls path_is_under() when nd->flags has LOOKUP_IS_SCOPED (LOOKUP_BENEATH|LOOKUP_IN_ROOT), which plain openat never sets. Random corruption would be unlikely to keep landing on the same check. - after downgrading the same VM to 6.8.0-1070-azure (noble), there have been 0 guest oopses in 4 days under the same workload. On 7.0 it crashed every 15-20 minutes. - a second, idle VM on the same host reproduced it on 7.0.0-38-generic (depmod; and once at mass process teardown), but not every run. The confounder is real, though. I'll re-test on a different machine before asking you to spend more time on this, and run apport-collect from a 7.0 kernel once I have a clean reproduction. Sorry for the noise in the original report. -- You received this bug notification because you are a member of Ubuntu Bugs, which is subscribed to Ubuntu. https://bugs.launchpad.net/bugs/2169338 Title: Kernel oops / GPF in path_is_under() from complete_walk() on openat — 7.0.0-34/-38-generic and 7.0.0-1017-azure, Hyper-V Gen2 guest To manage notifications about this bug go to: https://bugs.launchpad.net/ubuntu/+source/linux/+bug/2169338/+subscriptions -- ubuntu-bugs mailing list [email protected] https://lists.ubuntu.com/mailman/listinfo/ubuntu-bugs
