Re: [PATCH] kcov, usb: Fix invalid context sleep in softirq path on PREEMPT_RT

Sebastian Andrzej Siewior
2025-08-11T08:31:39Z

On 2025-08-09 02:35:48 [+0900], Yunseong Kim wrote:
> Hi Sebastian,
Hi Yunseong,

> > Could someone maybe test this?
>
> As you requested, I have tested your patch on my setup.
>
> I can check that your patch resolves the issue. I have been running
> the syzkaller for several hours, and the "sleeping function called
> from invalid context" bug is no longer triggered.

Thank you. I just sent this as a proper patch assuming kcov still does
what it should. I just don't understand why this triggers after moving
to workqueues and did not with the tasklet setup. Other that than
workqueue code has a bit more overhead, it is the same thing.

> I really impressed your "How to Not Break PREEMPT_RT" talk at LPC 22.

Thank you.

>
> Tested-by: Yunseong Kim <ysk@kzalloc.com>
>
>
> Thanks,
>
> Yunseong Kim

Sebastian