Re: 2.6.30-rc2-git2: Reported regressions from 2.6.29

From: Linus Torvalds
Date: Fri Apr 17 2009 - 23:06:18 EST




On Sat, 18 Apr 2009, leiming wrote:
>
> >From 5715e310a939f3f7cd3e88eae8f25fedbb28def4 Mon Sep 17 00:00:00 2001
> From: Ming Lei <tom.leiming@xxxxxxxxx>
> Date: Wed, 15 Apr 2009 22:32:51 +0800
> Subject: [PATCH] V4L/DVB:usbvideo:fix uvc resume failed
>
> Now urb buffers is not freed before suspend, so uvc_alloc_urb_buffers
> should return packet counts allocated originally during uvc resume
> , instead of zero.
>
> This patch is against v2.6.30-rc2.
>
> Signed-off-by: Ming Lei <tom.leiming@xxxxxxxxx>
> ---
> drivers/media/video/uvc/uvc_video.c | 2 +-
> 1 files changed, 1 insertions(+), 1 deletions(-)
>
> diff --git a/drivers/media/video/uvc/uvc_video.c b/drivers/media/video/uvc/uvc_video.c
> index a95e173..c050b22 100644
> --- a/drivers/media/video/uvc/uvc_video.c
> +++ b/drivers/media/video/uvc/uvc_video.c
> @@ -742,7 +742,7 @@ static int uvc_alloc_urb_buffers(struct uvc_video_device *video,
>
> /* Buffers are already allocated, bail out. */
> if (video->urb_size)
> - return 0;
> + return DIV_ROUND_UP(video->urb_size, psize);

I don't think this is right. It should round _down_.

It's supposed to return 'npackets', but if you pass it a different packet
size than it was passed originally, it can now return a potentially bigger
number than the already allocated buffer, no?

So I think it should round down (ie use a regular divide). No?

Linuse
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