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]
Message-ID: <1287495832.16971.368.camel@gandalf.stny.rr.com>
Date:	Tue, 19 Oct 2010 09:43:52 -0400
From:	Steven Rostedt <rostedt@...dmis.org>
To:	Arnd Bergmann <arnd@...db.de>
Cc:	Greg KH <greg@...ah.com>, linux-kernel@...r.kernel.org,
	Christoph Hellwig <hch@...radead.org>,
	Ingo Molnar <mingo@...e.hu>, Dave Airlie <airlied@...il.com>,
	dri-devel@...ts.freedesktop.org,
	ksummit-2010-discuss@...ts.linux-foundation.org
Subject: Re: [Ksummit-2010-discuss] [v2] Remaining BKL users, what to do

On Tue, 2010-10-19 at 15:36 +0200, Arnd Bergmann wrote:
> [trimming Cc list]
> 
> On Tuesday 19 October 2010, Steven Rostedt wrote:
> > I think we also need to cover the PREEMPT case too. But that could be a
> > compile time check, since you can't boot a preempt kernel and make it
> > non preempt.
> 
> Right. Can we turn the lock_kernel() into preempt_disable() in these
> drivers when we know we never run on SMP?

I'm not sure that will work. A holder of the BKL can call schedule or
even a mutex. The schedule code will drop the BKL and re-enable
preemption. Unless the code is known not to schedule while holding BKL,
we would need to open code the preempt_enable() around the locations
that the code may schedule.

-- Steve


--
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/

Powered by blists - more mailing lists

Powered by Openwall GNU/*/Linux Powered by OpenVZ