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Message-ID: <1948d519-9ec0-e874-d51a-6d9f2f5ca3f6@linaro.org>
Date:   Tue, 2 Aug 2022 09:43:59 +0300
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Subject: Re: [PATCH] drm/msm/gpu: Drop qos request if
 devm_devfreq_add_device() fails
Content-Language: en-GB
To:     Bjorn Andersson <bjorn.andersson@linaro.org>,
        Rob Clark <robdclark@gmail.com>,
        Abhinav Kumar <quic_abhinavk@quicinc.com>
Cc:     Sean Paul <sean@poorly.run>, David Airlie <airlied@linux.ie>,
        Daniel Vetter <daniel@ffwll.ch>, linux-arm-msm@vger.kernel.org,
        dri-devel@lists.freedesktop.org, freedreno@lists.freedesktop.org,
        linux-kernel@vger.kernel.org
References: <20220708162632.3529864-1-bjorn.andersson@linaro.org>
From:   Dmitry Baryshkov <dmitry.baryshkov@linaro.org>
In-Reply-To: <20220708162632.3529864-1-bjorn.andersson@linaro.org>
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On 08/07/2022 19:26, Bjorn Andersson wrote:
> In the event that devm_devfreq_add_device() fails the device's qos freq
> list is left referencing df->idle_freq and df->boost_freq. Attempting to
> initialize devfreq again after a probe deferral will then cause invalid
> memory accesses in dev_pm_qos_add_request().
> 
> Fix this by dropping the requests in the error path.
> 
> Fixes: 7c0ffcd40b16 ("drm/msm/gpu: Respect PM QoS constraints")
> Signed-off-by: Bjorn Andersson <bjorn.andersson@linaro.org>

Reviewed-by: Dmitry Baryshkov <dmitry.baryshkov@linaro.org>

> ---
>   drivers/gpu/drm/msm/msm_gpu_devfreq.c | 2 ++
>   1 file changed, 2 insertions(+)


-- 
With best wishes
Dmitry