linux-kernel - Re: [PATCH] video4linux: Push down the BKL

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]

Date:	Fri, 23 May 2008 08:28:49 +0200
From:	Hans Verkuil <hverkuil@...all.nl>
To:	video4linux-list@...hat.com
Cc:	linux-kernel@...r.kernel.org, Alan Cox <alan@...rguk.ukuu.org.uk>
Subject: Re: [PATCH] video4linux: Push down the BKL

On Friday 23 May 2008 08:16:05 Hans Verkuil wrote:
> On Friday 23 May 2008 04:08:04 Andy Walls wrote:
> > On Thu, 2008-05-22 at 22:37 +0100, Alan Cox wrote:
> > > For most drivers the generic ioctl handler does the work and we
> > > update it and it becomes the unlocked_ioctl method. Older drivers
> > > use the usercopy method so we make it do the work. Finally there
> > > are a few special cases.
> > >
> > > Signed-off-by: Alan Cox <alan@...hat.com>
> >
> > I'd like to start planning out the changes to eliminate the BKL
> > from cx18.
> >
> > Could someone give me a brief education as to what elements of
> > cx18/ivtv_v4l2_do_ioctl() would be forcing the use of the BKL for
> > these drivers' ioctls?   I'm assuming it's not the
> > mutex_un/lock(&....->serialize_lock) and that the answer's not in
> > the diff.
>
> To the best of my knowledge there is no need for a BKL in ivtv or
> cx18. It was just laziness on my part that I hadn't switched to
> unlocked_ioctl yet. If you know of a reason why it should be kept for
> now, then I'd like to know, otherwise the BKL can be removed
> altogether for ivtv/cx18. I suspect you just pushed the lock down
> into the driver and in that case you can just remove it for
> ivtv/cx18.

Hmm, of course you just pushed down the lock, the subject said so. 
Sorry, it's early morning here and I'm apparently not yet fully 
awake :-)

Regards,

	Hans
--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@...r.kernel.org
More majordomo info at  http://vger.kernel.org/majordomo-info.html
Please read the FAQ at  http://www.tux.org/lkml/