On 2026-05-09 17:09:44 [+0900], Tetsuo Handa wrote:
> In CONFIG_PREEMPT_RT=y kernels, softirqs are executed in a per-CPU
> ksoftirqd thread or in the context of the task that raised the softirq.
> This means in_task() can return true even while serving softirqs. This
> behavior causes KCOV to incorrectly identify the context, leading to state
> corruption and various kcov-related warnings reported by syzbot.

I need to digest the remaining email but in_task() should not return on
PREEMPT_RT if a softirq is served. Regardless if it happens in ksoftirqd
or in the context of the task raised via local_bh_enable().

I will digest this later.

Sebastian