linux-kernel - Re: [PATCH 5/6] drm: vkms: Prepare `vkms_wb_encoder_atomic

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

Message-ID: <e9cbdad7-416a-65fe-eb50-1cbb42a01e7b@gmail.com>
Date:   Mon, 18 Oct 2021 14:41:33 -0300
From:   Igor Matheus Andrade Torrente <igormtorrente@...il.com>
To:     Thomas Zimmermann <tzimmermann@...e.de>,
        rodrigosiqueiramelo@...il.com, melissa.srw@...il.com
Cc:     hamohammed.sa@...il.com, daniel@...ll.ch, airlied@...ux.ie,
        contact@...rsion.fr, leandro.ribeiro@...labora.com,
        dri-devel@...ts.freedesktop.org, linux-kernel@...r.kernel.org,
        lkcamp@...ts.libreplanetbr.org
Subject: Re: [PATCH 5/6] drm: vkms: Prepare `vkms_wb_encoder_atomic_check` to
 accept multiple formats

Hello,

On 10/18/21 7:14 AM, Thomas Zimmermann wrote:
> Hi
> 
> Am 05.10.21 um 22:16 schrieb Igor Matheus Andrade Torrente:
>> Currently, the vkms atomic check only goes through the first position of
>> the `vkms_wb_formats` vector.
>>
>> This change prepares the atomic_check to check the entire vector.
>>
>> Signed-off-by: Igor Matheus Andrade Torrente <igormtorrente@...il.com>
>> ---
>>   drivers/gpu/drm/vkms/vkms_writeback.c | 11 ++++++++++-
>>   1 file changed, 10 insertions(+), 1 deletion(-)
>>
>> diff --git a/drivers/gpu/drm/vkms/vkms_writeback.c 
>> b/drivers/gpu/drm/vkms/vkms_writeback.c
>> index 5a3e12f105dc..56978f499203 100644
>> --- a/drivers/gpu/drm/vkms/vkms_writeback.c
>> +++ b/drivers/gpu/drm/vkms/vkms_writeback.c
>> @@ -30,6 +30,8 @@ static int vkms_wb_encoder_atomic_check(struct 
>> drm_encoder *encoder,
>>   {
>>       struct drm_framebuffer *fb;
>>       const struct drm_display_mode *mode = &crtc_state->mode;
>> +    bool format_supported = false;
>> +    int i;
>>       if (!conn_state->writeback_job || !conn_state->writeback_job->fb)
>>           return 0;
>> @@ -41,7 +43,14 @@ static int vkms_wb_encoder_atomic_check(struct 
>> drm_encoder *encoder,
>>           return -EINVAL;
>>       }
>> -    if (fb->format->format != vkms_wb_formats[0]) {
>> +    for (i = 0; i < ARRAY_SIZE(vkms_wb_formats); i++) {
>> +        if (fb->format->format == vkms_wb_formats[i]) {
>> +            format_supported = true;
>> +            break;
>> +        }
>> +    }
> 
> At a minimum, this loop should be in a helper function. But more 
> generally, I'm surprised that this isn't already covered by the DRM's 
> atomic helpers.

Ok, I can wrap it in a new function.

AFAIK the DRM doesn't cover it. But I may be wrong...

> 
> Best regards
> Thomas
> 
>> +
>> +    if (!format_supported) {
>>           DRM_DEBUG_KMS("Invalid pixel format %p4cc\n",
>>                     &fb->format->format);
>>           return -EINVAL;
>>
>