linux-kernel - Re: [PATCH v2] drm/msm/dp: do not complete dp_aux_cmd_fifo

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite: Windows password security audit tool. GUI, reports in PDF.

[<prev] [next>] [<thread-prev] [day] [month] [year] [list]

Message-ID: <f11ec176-35b8-6e8a-a9a1-63f73a000d13@quicinc.com>
Date:   Thu, 15 Dec 2022 13:57:31 -0800
From:   Abhinav Kumar <quic_abhinavk@...cinc.com>
To:     Dmitry Baryshkov <dmitry.baryshkov@...aro.org>,
        Stephen Boyd <swboyd@...omium.org>,
        Kuogee Hsieh <quic_khsieh@...cinc.com>, <agross@...nel.org>,
        <airlied@...il.com>, <andersson@...nel.org>, <daniel@...ll.ch>,
        <dianders@...omium.org>, <robdclark@...il.com>, <sean@...rly.run>,
        <vkoul@...nel.org>
CC:     <quic_sbillaka@...cinc.com>, <freedreno@...ts.freedesktop.org>,
        <dri-devel@...ts.freedesktop.org>, <linux-arm-msm@...r.kernel.org>,
        <linux-kernel@...r.kernel.org>
Subject: Re: [PATCH v2] drm/msm/dp: do not complete dp_aux_cmd_fifo_tx() if
 irq is not for aux transfer



On 12/15/2022 1:15 PM, Dmitry Baryshkov wrote:
> On 15/12/2022 22:10, Stephen Boyd wrote:
>> Quoting Dmitry Baryshkov (2022-12-15 10:46:42)
>>> On 15/12/2022 20:32, Kuogee Hsieh wrote:
>>>>        if (!aux->cmd_busy)
>>>>                return;
>>>>
>>>>        if (aux->native)
>>>> -             dp_aux_native_handler(aux, isr);
>>>> +             ret = dp_aux_native_handler(aux, isr);
>>>>        else
>>>> -             dp_aux_i2c_handler(aux, isr);
>>>> +             ret = dp_aux_i2c_handler(aux, isr);
>>>>
>>>> -     complete(&aux->comp);
>>>> +     if (ret == IRQ_HANDLED)
>>>> +             complete(&aux->comp);
>>>
>>> Can you just move the complete() into the individual handling functions?
>>> Then you won't have to return the error code from dp_aux_*_handler() at
>>> all. You can check `isr' in that function and call complete if there was
>>> any error.
>>
>> I'd prefer we apply my patch and pass the irqreturn_t variable to the
>> caller of this function so spurious irqs are shutdown. Should I send it
>> as a proper patch?
> 
> I'm for handling the spurious IRQs in a proper way. However I believe 
> that it's not related to the issue Kuogee is trying to fix.
> 
> Thus I think we should have two separate patches: one fixing the EDID 
> corruption issue (for which the proper fix is !isr check, IIUC) and the 
> irqreturn_t. And for the irqreturn_t it might be beneficial to move 
> complete() call to the dp_aux_foo_handler(). Or might be not. That would 
> depend on the patch itself.

Ack.
> 
>