Re: [BUG] WARNING in perf_cgroup_switch: EVENT_FROZEN assertion during kthread sched-out

[Peter Zijlstra]

On Wed, Apr 01, 2026 at 10:15:56AM -0400, Christopher Lusk wrote:
> Hello,
> 
> I'm hitting a WARNING in perf_cgroup_switch() on kernel 6.12.0 during
> continuous syzkaller fuzzing. The assertion WARN_ON_ONCE(ctx->is_active &
> EVENT_FROZEN) in __perf_ctx_lock() fires when the rcu_preempt kthread is
> being scheduled out.
> 
> Kernel: 6.12.0 (RHEL 10 build, no out-of-tree modules)

Does this reproduce on anything recent?