linux-kernel - Re: [PATCH v2 33/36] media: ti: cal: Fix misuse of min_buffers

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: <85b8cdf7-a05f-44d2-a678-af121231261f@xs4all.nl>
Date:   Mon, 4 Dec 2023 16:10:08 +0100
From:   Hans Verkuil <hverkuil@...all.nl>
To:     Benjamin Gaignard <benjamin.gaignard@...labora.com>,
        mchehab@...nel.org, tfiga@...omium.org, m.szyprowski@...sung.com,
        matt.ranostay@...sulko.com
Cc:     linux-kernel@...r.kernel.org, linux-media@...r.kernel.org,
        linux-staging@...ts.linux.dev, kernel@...labora.com,
        Benoit Parrot <bparrot@...com>
Subject: Re: [PATCH v2 33/36] media: ti: cal: Fix misuse of min_buffers_needed
 field

On 04/12/2023 14:23, Benjamin Gaignard wrote:
> 'min_buffers_needed' is suppose to be used to indicate the number
> of buffers needed by DMA engine to start streaming.
> Cal driver doesn't use DMA engine and just want to specify
> the minimum number of buffers to allocate when calling VIDIOC_REQBUFS.
> That 'min_reqbufs_allocation' field purpose so use it.
> 
> Signed-off-by: Benjamin Gaignard <benjamin.gaignard@...labora.com>
> CC: Benoit Parrot <bparrot@...com>
> ---
>  drivers/media/platform/ti/cal/cal-video.c | 2 +-
>  1 file changed, 1 insertion(+), 1 deletion(-)
> 
> diff --git a/drivers/media/platform/ti/cal/cal-video.c b/drivers/media/platform/ti/cal/cal-video.c
> index e1c5e68e945b..04709dac7221 100644
> --- a/drivers/media/platform/ti/cal/cal-video.c
> +++ b/drivers/media/platform/ti/cal/cal-video.c
> @@ -1010,7 +1010,7 @@ int cal_ctx_v4l2_init(struct cal_ctx *ctx)
>  	q->mem_ops = &vb2_dma_contig_memops;
>  	q->timestamp_flags = V4L2_BUF_FLAG_TIMESTAMP_MONOTONIC;
>  	q->lock = &ctx->mutex;
> -	q->min_buffers_needed = 3;
> +	q->min_reqbufs_allocation = 3;
>  	q->dev = ctx->cal->dev;
>  
>  	ret = vb2_queue_init(q);

This driver definitely needs 1 buffer before it can start DMA, so set
min_buffers_needed to 1.

Regards,

	Hans