linux-kernel - Re: What if a TLB flush needed to sleep?

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: <alpine.LFD.1.00.0803262121440.3781@apollo.tec.linutronix.de>
Date:	Wed, 26 Mar 2008 21:29:13 +0100 (CET)
From:	Thomas Gleixner <tglx@...utronix.de>
To:	Christoph Lameter <clameter@....com>
cc:	"Luck, Tony" <tony.luck@...el.com>, linux-arch@...r.kernel.org,
	linux-mm@...ck.org, linux-kernel@...r.kernel.org
Subject: Re: What if a TLB flush needed to sleep?

On Wed, 26 Mar 2008, Christoph Lameter wrote:

> On Tue, 25 Mar 2008, Luck, Tony wrote:
> 
> > 2) Is it feasible to rearrange the MM code so that we don't
> > hold any locks while doing a TLB flush?  Or should I implement
> > some sort of spin_only_semaphore?
> 
> The EMM notifier V2 patchset contains two patches that 
> convert the immap_lock and the anon_vma lock to semaphores.

Please use a mutex, not a semaphore. semaphores should only be used
when you need a counting sempahore.

Thanks,

	tglx
--
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/