Re: [PATCH rtw-next v6 0/4] wifi: rtw88: sdio: Fix unhandled RX request interrupt storm

[Luka Gejak]

Hi Alastair,

October 14, 2026 at 9:44 AM, "Alastair D'Silva" <alastair@xxxxxxxxxxx> wrote:

> On 3081-based SDIO chips (observed on RTL8821CS; RTL8822CS is inferred to
> be affected as it shares the 3081 architecture), hardware does not
> automatically clear the REG_SDIO_HISR_RX_REQUEST status bit when the RX
> FIFO becomes empty. Masking this bit out in software before writing back
> to HISR prevented it from ever being acknowledged in hardware, trapping
> the CPU core in an infinite interrupt storm that locked up the system upon
> receiving network traffic.

There are three 3081 parts with an SDIO front end, not two. 8822BS is
RTW_WCPU_3081 as well (rtw8822b.c:2527) and rtw8822bs.c is built as
rtw88_8822bs.o, so naming 8821CS and 8822CS only leaves it out. Patch 3
changes the interrupt path for all three at once and only the 8821CS was
probed, which is the one thing I would add to a series that Cc's stable.
If there is no run on 8822BS and 8822CS to hand, saying the same for both
would do, the way the cover already does for 8822CS.

Best regards,
Luka Gejak