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References: <20231213210644.8702-1-robdclark@gmail.com> <ZXqr0RFw9KsP876v@hovoldconsulting.com>
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From:   Dmitry Baryshkov <dmitry.baryshkov@linaro.org>
Date:   Thu, 14 Dec 2023 13:04:43 +0200
Message-ID: <CAA8EJpoSvaq9imP-dT4p=4jveZyFmh=OoWOP7jWGo4OYkHQDTA@mail.gmail.com>
Subject: Re: [PATCH] soc: qcom: pmic_glink: Fix boot when QRTR=m
To:     Johan Hovold <johan@kernel.org>
Cc:     Rob Clark <robdclark@gmail.com>, linux-arm-msm@vger.kernel.org,
        Rob Clark <robdclark@chromium.org>,
        Andy Gross <agross@kernel.org>,
        Bjorn Andersson <andersson@kernel.org>,
        Konrad Dybcio <konrad.dybcio@linaro.org>,
        open list <linux-kernel@vger.kernel.org>
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On Thu, 14 Dec 2023 at 09:16, Johan Hovold <johan@kernel.org> wrote:
>
> On Wed, Dec 13, 2023 at 01:06:43PM -0800, Rob Clark wrote:
> > From: Rob Clark <robdclark@chromium.org>
> >
> > We need to bail out before adding/removing devices, if we are going
> > to -EPROBE_DEFER.  Otherwise boot will get stuck forever at
> > deferred_probe_initcall().
>
> Can please you expand on why this is a problem here in the commit
> message?
>
> The aux devices appear to be tore down correctly in the probe error
> paths so how exactly does that lead to deferred_probe_initcall() being
> stuck? This sounds like we may have a problem elsewhere which this patch
> is papering over.

This is a known problem. Successful probes during the probe deferral
loop causes the whole loop to be reiterated. Creating child devices
usually results in  a successful probe. Aso I thought that just
creating new device also causes a reprobe, but I can not find any
evidence now.

>
> Also where does the probe deferral come from in your case?
> pdr_handle_alloc()?
>
> If this is a correct fix, I'd also expect there to be a Fixes and
> CC-stable tag.
>
> Johan
>


-- 
With best wishes
Dmitry