linux-kernel - Re: [patch] spinlock debug: make looping nicer

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: <20070622070056.GA1778@ff.dom.local>
Date:	Fri, 22 Jun 2007 09:00:56 +0200
From:	Jarek Poplawski <jarkao2@...pl>
To:	Ingo Molnar <mingo@...e.hu>
Cc:	Linus Torvalds <torvalds@...ux-foundation.org>,
	Eric Dumazet <dada1@...mosbay.com>,
	Chuck Ebbert <cebbert@...hat.com>,
	Miklos Szeredi <miklos@...redi.hu>, chris@...ee.ca,
	linux-kernel@...r.kernel.org, tglx@...utronix.de,
	akpm@...ux-foundation.org
Subject: Re: [patch] spinlock debug: make looping nicer

On Thu, Jun 21, 2007 at 11:15:25PM +0200, Ingo Molnar wrote:
> 
> * Linus Torvalds <torvalds@...ux-foundation.org> wrote:
> 
> > On Thu, 21 Jun 2007, Ingo Molnar wrote:
> > > 
> > > btw., back then we also tried a spin_is_locked() based inner loop 
> > > but it didnt help the ->tree_lock lockups either. In any case i very 
> > > much agree that the 'nicer' looping should be added again - the 
> > > patch below does that. (build and boot tested)
> > 
> > Ok, I'm definitely not going to apply it right now, though.
> 
> yeah, very much so. Lots of distros ship with spinlock debugging enabled 
> (at least in their betas), we dont want to break that accidentally.

But, I hope, Miklos will manage to find some time to try this
patch or spinlock debugging on, to confirm the nature isn't
mocking us here... 

Miklos, I'd appreciate it very much if you could also exclude my
another extremely silly suspicion, and try with only cpu_relax()
instead of yield() (but without removing if (preempted)) in
wait_task_inactive().

Thanks & regards,
Jarek P.
-
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/