RE: PROBLEM: kernel warns about voluntary context switch within RCU critical section in rtw88_usb

From: Ping-Ke Shih
Date: Tue Aug 22 2023 - 01:47:16 EST




> -----Original Message-----
> From: Kalle Valo <kvalo@xxxxxxxxxx>
> Sent: Tuesday, August 22, 2023 1:42 PM
> To: Ping-Ke Shih <pkshih@xxxxxxxxxxx>
> Cc: Sergey Korolev <korolev.sergey@xxxxxxxxx>; linux-wireless@xxxxxxxxxxxxxxx;
> linux-kernel@xxxxxxxxxxxxxxx
> Subject: Re: PROBLEM: kernel warns about voluntary context switch within RCU critical section in rtw88_usb
>
> Ping-Ke Shih <pkshih@xxxxxxxxxxx> writes:
>
> > From: Sergey Korolev <korolev.sergey@xxxxxxxxx>
> > Sent: Monday, August 21, 2023 10:28 PM
> > To: Ping-Ke Shih <pkshih@xxxxxxxxxxx>; Kalle Valo <kvalo@xxxxxxxxxx>; linux-wireless@xxxxxxxxxxxxxxx;
> linux-kernel@xxxxxxxxxxxxxxx
> > Subject: PROBLEM: kernel warns about voluntary context switch within RCU critical section in rtw88_usb
> >>
> >> Please note I use an unmodified driver from the upstream 28c11c29494f1b34e39641eead9c60a8bd26170d
> >> ("wifi: rtw88: fix not entering PS mode after AP stops") build for 6.2 kernel (Ubuntu 23.04).
> >
> > I feel Martin has been addressed this problem during development of SDIO and USB
> > by 8a1e2fd8e2da ("wifi: rtw88: Move register access from rtw_bf_assoc() outside the RCU")
> > Please take a look if this patch is existing in your source.
>
> Commit 8a1e2fd8e2da was merged to v6.3-rc1 so v6.2 won't have it.
>

Sergey said he uses driver from 28c11c29494f that is v6.4-rc5 or v6.5, so
seemingly it should include Martin's patch. Not sure what is wrong.

Ping-Ke