[PATCH v2] ath10k: add flag to protect napi operation to avoid dead loop hang for SDIO

[Krishna Chaitanya]

On Mon, Aug 24, 2020 at 3:10 PM Wen Gong <wgong at codeaurora.org> wrote:
>
> On 2020-08-24 16:35, Krishna Chaitanya wrote:
> > On Mon, Aug 24, 2020 at 10:03 AM Wen Gong <wgong at codeaurora.org> wrote:
> >>
> >> It happened "Kernel panic - not syncing: hung_task: blocked tasks"
> >> when
> >> test simulate crash and ifconfig down/rmmod meanwhile.
> >>
> ...
> >>
> >>  #ifdef CONFIG_PM
> > Even though your DUT is SDIO based we should be doing this in general
> > for all, no?
> > core_restart + hif_stop is common to all.
> this patch does not have core_restart.
I was referring to the combination which is causing the issue.

> I dit not hit the issue for others bus(PCIe,SNOC...), so I can not
> change them with a
> assumption they also have this issue.
But that doesn't make sense, the combination is being hit for others also.
(they should also endup calling napi_disable twice?) or they are using
some other check to avoid this (doesn't appear so from a quick look at the
code).

So, I am back to my initial guess that the SDIO specific async_rx_work is
causing/aggravating this issue.