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From:   Evan Green <evgreen@chromium.org>
Date:   Tue, 2 Jun 2020 10:44:05 -0700
Message-ID: <CAE=gft7sbh_S_GiRohtMmdMN9JzQhG0m3bUerwrmzhjmXucGKw@mail.gmail.com>
Subject: Re: [PATCH 1/2] remoteproc: qcom: q6v5: Update running state before
 requesting stop
To:     Sibi Sankar <sibis@codeaurora.org>
Cc:     Bjorn Andersson <bjorn.andersson@linaro.org>,
        Andy Gross <agross@kernel.org>,
        linux-arm-msm <linux-arm-msm@vger.kernel.org>,
        linux-remoteproc@vger.kernel.org,
        LKML <linux-kernel@vger.kernel.org>,
        Ohad Ben Cohen <ohad@wizery.com>, rohitkr@codeaurora.org,
        stable@vger.kernel.org
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On Tue, Jun 2, 2020 at 9:33 AM Sibi Sankar <sibis@codeaurora.org> wrote:
>
> Sometimes the stop triggers a watchdog rather than a stop-ack. Update
> the running state to false on requesting stop to skip the watchdog
> instead.
>
> Error Logs:
> $ echo stop > /sys/class/remoteproc/remoteproc0/state
> ipa 1e40000.ipa: received modem stopping event
> remoteproc-modem: watchdog received: sys_m_smsm_mpss.c:291:APPS force stop
> qcom-q6v5-mss 4080000.remoteproc-modem: port failed halt
> ipa 1e40000.ipa: received modem offline event
> remoteproc0: stopped remote processor 4080000.remoteproc-modem
>
> Fixes: 3b415c8fb263 ("remoteproc: q6v5: Extract common resource handling")
> Cc: stable@vger.kernel.org
> Signed-off-by: Sibi Sankar <sibis@codeaurora.org>
> ---

Are you sure you want to tolerate this behavior from MSS? This is a
graceful shutdown, modem shouldn't have a problem completing the
proper handshake. If they do, isn't that a bug on the modem side?

I just worry this will mask real issues that happen during graceful shutdown.
-Evan