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Date:   Fri, 9 Dec 2022 13:53:31 +0200 (EET)
From:   Kai Vehmanen <kai.vehmanen@linux.intel.com>
To:     Ricardo Ribalda <ribalda@chromium.org>
cc:     Oliver Neukum <oneukum@suse.com>, Juergen Gross <jgross@suse.com>,
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        Ard Biesheuvel <ardb@kernel.org>,
        Ranjani Sridharan <ranjani.sridharan@linux.intel.com>,
        "Rafael J. Wysocki" <rafael@kernel.org>,
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Subject: Re: [PATCH v8 3/3] ASoC: SOF: Fix deadlock when shutdown a frozen
 userspace
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References: <20221127-snd-freeze-v8-0-3bc02d09f2ce@chromium.org> <20221127-snd-freeze-v8-3-3bc02d09f2ce@chromium.org> <716e5175-7a44-7ae8-b6bb-10d9807552e6@suse.com> <CANiDSCtwSb50sjn5tM7jJ6W2UpeKzpuzng+RdJuywiC3-j2zdg@mail.gmail.com>
 <d3730d1d-6f92-700a-06c4-0e0a35e270b0@suse.com> <CANiDSCtm7dCst_atiWk=ZcK_D3=VzvD0+kWXVQr4gEn--JjGkw@mail.gmail.com>
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Hi,

On Thu, 1 Dec 2022, Ricardo Ribalda wrote:

> On Thu, 1 Dec 2022 at 14:22, 'Oliver Neukum' via Chromeos Kdump <chromeos-kdump@google.com> wrote:
> >
> > On 01.12.22 14:03, Ricardo Ribalda wrote:
> > > This patchset does not modify this behaviour. It simply fixes the
> > > stall for kexec().
> > >
> > > The  patch that introduced the stall:
> > > 83bfc7e793b5 ("ASoC: SOF: core: unregister clients and machine drivers
> > > in .shutdown")
> >
> > That patch is problematic. I would go as far as saying that
> > it needs to be reverted.
> 
> It fixes a real issue. We have not had any complaints until we tried
> to kexec in the platform.
> I wont recommend reverting it until we have an alternative implementation.
> 
> kexec is far less common than suspend/reboot.

I've posted an alternative to ALSA list that reverts the problematic
patch and fixes the problem (the patch was originally addressing)
in a different way:

https://mailman.alsa-project.org/pipermail/alsa-devel/2022-December/209776.html

No changes outside sound/soc/ are needed with this approach.

Br, Kai