Re: [PATCH] wireless: ath10k: Return early in ath10k_qmi_event_server_exit() to avoid hard crash on reboot

[Sibi Sankar]

On 2020-06-03 15:37, govinds@xxxxxxxxxxxxxx wrote:
> Hi Mani,
>
> On 2020-06-03 05:57, Manivannan Sadhasivam wrote:
> > On Tue, Jun 02, 2020 at 01:04:26PM -0700, Brian Norris wrote:
> > > On Tue, Jun 2, 2020 at 12:40 PM John Stultz <john.stultz@xxxxxxxxxx> 
> > > wrote:
> > > > On Tue, Jun 2, 2020 at 12:16 PM Brian Norris <briannorris@xxxxxxxxxxxx> wrote:
> > > > > On Mon, Jun 1, 2020 at 10:25 PM John Stultz <john.stultz@xxxxxxxxxx> wrote:
> > > > > >
> > > > > > Ever since 5.7-rc1, if we call
> > > > > > ath10k_qmi_remove_msa_permission(), the db845c hard crashes on
> > > > > > reboot, resulting in the device getting stuck in the usb crash
> > > > > > debug mode and not coming back up wihthout a hard power off.
> > > > > >
> > > > > > This hack avoids the issue by returning early in
> > > > > > ath10k_qmi_event_server_exit().
> > > > > >
> > > > > > A better solution is very much desired!
> > > > >
> > > > > Any chance you can bisect what caused this? There are a lot of
> > > > > non-ath10k pieces involved in this stuff.
> > > >
> > > > Amit had spent some work on chasing it down to the in kernel qrtr-ns
> > > > work, and reported it here:
> > > >   https://lists.infradead.org/pipermail/ath10k/2020-April/014970.html
> > > >
> > > > But that discussion seemingly stalled out, so I came up with this hack
> > > > to workaround it for us.
> > >
> > > If I'm reading it right, then that means we should revert this stuff
> > > from v5.7-rc1:
> > >
> > > 0c2204a4ad71 net: qrtr: Migrate nameservice to kernel from userspace
> > >
> > > At least, until people can resolve the tail end of that thread. New
> > > features (ath11k, etc.) are not a reason to break existing features
> > > (ath10k/wcn3990).
> >
> > I don't agree with this. If you read through the replies to the bug 
> > report,
> > it is clear that NS migration uncovered a corner case or even a bug. 
> > So we
> > should try to fix that indeed.
> >
> > Govind: Did you get chance to work on fixing this issue?
>
> I have done basic testing by moving msa map/unmap from qmi service
> callbacks to init/de-init path.
> I will send patch for review.
> Reason for del_server needs to investigated from rproc side.

Govind,
On receiving SIGTERM, rmtfs would try
to perform a graceful shutdown of the
modem, that should be the source of
the del_server.

> > Thanks,
> > Mani
> >
> > > Brian
>
> Thanks,
> Govind

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