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From: Dmitry Baryshkov <dmitry.baryshkov@linaro.org>
Date: Wed, 3 Apr 2024 06:08:38 +0300
Message-ID: <CAA8EJpqkU2bBwkdW5aQ=ZKvPBoRWaxFVQAxmg76zhLQqV4C-UQ@mail.gmail.com>
Subject: Re: [PATCH 1/2] soc: qcom: pmic_glink: don't traverse clients list
 without a lock
To: Andrew Halaney <ahalaney@redhat.com>
Cc: Bjorn Andersson <andersson@kernel.org>, Konrad Dybcio <konrad.dybcio@linaro.org>, 
	Neil Armstrong <neil.armstrong@linaro.org>, linux-arm-msm@vger.kernel.org, 
	linux-kernel@vger.kernel.org
Content-Type: text/plain; charset="UTF-8"

On Tue, 2 Apr 2024 at 20:56, Andrew Halaney <ahalaney@redhat.com> wrote:
>
> On Tue, Apr 02, 2024 at 08:07:06PM +0300, Dmitry Baryshkov wrote:
> > Take the client_lock before traversing the clients list at the
> > pmic_glink_state_notify_clients() function. This is required to keep the
> > list traversal safe from concurrent modification.
> >
> > Fixes: 58ef4ece1e41 ("soc: qcom: pmic_glink: Introduce base PMIC GLINK driver")
> > Signed-off-by: Dmitry Baryshkov <dmitry.baryshkov@linaro.org>
> > ---
> >  drivers/soc/qcom/pmic_glink.c | 2 ++
> >  1 file changed, 2 insertions(+)
> >
> > diff --git a/drivers/soc/qcom/pmic_glink.c b/drivers/soc/qcom/pmic_glink.c
> > index f913e9bd57ed..c999358771b3 100644
> > --- a/drivers/soc/qcom/pmic_glink.c
> > +++ b/drivers/soc/qcom/pmic_glink.c
> > @@ -168,8 +168,10 @@ static void pmic_glink_state_notify_clients(struct pmic_glink *pg)
> >       }
>
> Does pmic_glink_rpmsg_callback() deserve similar locking when traversing
> the clients list?

True. Will fix in v2.

>
> >
> >       if (new_state != pg->client_state) {
> > +             mutex_lock(&pg->client_lock);
> >               list_for_each_entry(client, &pg->clients, node)
> >                       client->pdr_notify(client->priv, new_state);
> > +             mutex_unlock(&pg->client_lock);
> >               pg->client_state = new_state;
> >       }
> >  }
> >
> > --
> > 2.39.2
> >
> >
>


-- 
With best wishes
Dmitry