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Message-ID: <1b6f21ce-1677-9d6e-f036-973a7f98a298@collabora.com>
Date:   Tue, 15 Mar 2022 16:05:00 +0300
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Subject: Re: [PATCH v2 1/8] drm/virtio: Correct drm_gem_shmem_get_sg_table()
 error handling
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To:     David Airlie <airlied@linux.ie>, Gerd Hoffmann <kraxel@redhat.com>,
        Gurchetan Singh <gurchetansingh@chromium.org>,
        Chia-I Wu <olvaffe@gmail.com>, Daniel Vetter <daniel@ffwll.ch>,
        Daniel Almeida <daniel.almeida@collabora.com>,
        Gert Wollny <gert.wollny@collabora.com>,
        Tomeu Vizoso <tomeu.vizoso@collabora.com>,
        Maarten Lankhorst <maarten.lankhorst@linux.intel.com>,
        Maxime Ripard <mripard@kernel.org>,
        Thomas Zimmermann <tzimmermann@suse.de>,
        Rob Herring <robh@kernel.org>,
        Steven Price <steven.price@arm.com>,
        Alyssa Rosenzweig <alyssa.rosenzweig@collabora.com>,
        Emil Velikov <emil.l.velikov@gmail.com>
Cc:     dri-devel@lists.freedesktop.org, linux-kernel@vger.kernel.org,
        Gustavo Padovan <gustavo.padovan@collabora.com>,
        Daniel Stone <daniel@fooishbar.org>,
        virtualization@lists.linux-foundation.org,
        Dmitry Osipenko <digetx@gmail.com>
References: <20220314224253.236359-1-dmitry.osipenko@collabora.com>
 <20220314224253.236359-2-dmitry.osipenko@collabora.com>
From:   Dmitry Osipenko <dmitry.osipenko@collabora.com>
In-Reply-To: <20220314224253.236359-2-dmitry.osipenko@collabora.com>
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On 3/15/22 01:42, Dmitry Osipenko wrote:
> drm_gem_shmem_get_sg_table() never ever returned NULL on error. Correct
> the error handling to avoid crash on OOM.
> 
> Cc: stable@vger.kernel.org
> Signed-off-by: Dmitry Osipenko <dmitry.osipenko@collabora.com>
> ---
>  drivers/gpu/drm/virtio/virtgpu_object.c | 6 ++++--
>  1 file changed, 4 insertions(+), 2 deletions(-)
> 
> diff --git a/drivers/gpu/drm/virtio/virtgpu_object.c b/drivers/gpu/drm/virtio/virtgpu_object.c
> index f293e6ad52da..bea7806a3ae3 100644
> --- a/drivers/gpu/drm/virtio/virtgpu_object.c
> +++ b/drivers/gpu/drm/virtio/virtgpu_object.c
> @@ -168,9 +168,11 @@ static int virtio_gpu_object_shmem_init(struct virtio_gpu_device *vgdev,
>  	 * since virtio_gpu doesn't support dma-buf import from other devices.
>  	 */
>  	shmem->pages = drm_gem_shmem_get_sg_table(&bo->base);
> -	if (!shmem->pages) {
> +	ret = PTR_ERR(shmem->pages);

This actually needs to be PTR_ERR_OR_ZERO. This code is changed to use
drm_gem_shmem_get_pages_sgt()+IS_ERR() by the further patch, so I just
missed the typo previously. I'll correct it in v3.