On Fri, May 23, 2025, Dave Hansen wrote: > On 5/23/25 09:57, Sean Christopherson wrote: > > Side topic, and *probably* unrelated to this series, I tripped the following > > WARN when running it through the KVM tests (though I don't think it has anything > > to do with KVM?). The WARN is the version of xfd_validate_state() that's guarded > > by CONFIG_X86_DEBUG_FPU=y. > > > > WARNING: CPU: 232 PID: 15391 at arch/x86/kernel/fpu/xstate.c:1543 xfd_validate_state+0x65/0x70 > > Huh, and the two processes getting hit by it: > > CPU: 232 UID: 0 PID: 15391 Comm: DefaultEventMan ... > CPU: 77 UID: 0 PID: 14821 Comm: futex-default-S ... > > don't _look_ like KVM test processes. Yeah, that's why I haven't dug into it, I don't really know where to start, and I don't even really know what triggered it. > My guess would be it's some mixture of KVM and a signal handler fighting with > XFD state. > > I take it this is a Sapphire Rapids system? Emerald Rapids > Is there anything interesting about the config other than CONFIG_X86_DEBUG_FPU? The only thing I can think of that's remotely interesting is CONFIG_PROVE_LOCKING=y. Other than that, it's a pretty vanilla config.
