Message-ID: <bee5d455-3e15-427a-d7a6-f633a748f4c3@redhat.com>
Date:   Fri, 10 Feb 2023 13:38:22 +0100
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Subject: Re: [PATCH] drm/shmem-helper: Fix locking for
 drm_gem_shmem_get_pages_sgt()
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From:   Javier Martinez Canillas <javierm@redhat.com>
To:     Asahi Lina <lina@asahilina.net>,
        Maarten Lankhorst <maarten.lankhorst@linux.intel.com>,
        Maxime Ripard <mripard@kernel.org>,
        Thomas Zimmermann <tzimmermann@suse.de>,
        David Airlie <airlied@gmail.com>,
        Daniel Vetter <daniel@ffwll.ch>
Cc:     linux-kernel@vger.kernel.org, dri-devel@lists.freedesktop.org,
        =?UTF-8?Q?Noralf_Tr=c3=b8nnes?= <noralf@tronnes.org>,
        asahi@lists.linux.dev, Alyssa Rosenzweig <alyssa@rosenzweig.io>
References: <20230205125124.2260-1-lina@asahilina.net>
 <a1cd8c74-98f4-bff0-0344-cbece787c6e8@redhat.com>
In-Reply-To: <a1cd8c74-98f4-bff0-0344-cbece787c6e8@redhat.com>
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On 2/6/23 19:47, Javier Martinez Canillas wrote:
> Hello Lina,
> 
> On 2/5/23 13:51, Asahi Lina wrote:
>> Other functions touching shmem->sgt take the pages lock, so do that here
>> too. drm_gem_shmem_get_pages() & co take the same lock, so move to the
>> _locked() variants to avoid recursive locking.
>>
>> Discovered while auditing locking to write the Rust abstractions.
>>
>> Fixes: 2194a63a818d ("drm: Add library for shmem backed GEM objects")
>> Fixes: 4fa3d66f132b ("drm/shmem: Do dma_unmap_sg before purging pages")
>> Signed-off-by: Asahi Lina <lina@asahilina.net>
>> ---
> 
> Good catch. The patch looks good to me.
> 
> Reviewed-by: Javier Martinez Canillas <javierm@redhat.com>
> 

Pushed this to drm-misc (drm-misc-next). Thanks!

-- 
Best regards,

Javier Martinez Canillas
Core Platforms
Red Hat