linux-kernel - Re: [PATCH] Documentation: kernel-locking: mutex_trylock cannot be used in interrupt context

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] [day] [month] [year] [list]

Message-Id: <201008191022.43524.rusty@rustcorp.com.au>
Date:	Thu, 19 Aug 2010 10:22:42 +0930
From:	Rusty Russell <rusty@...tcorp.com.au>
To:	Stefan Richter <stefanr@...6.in-berlin.de>
Cc:	linux-kernel@...r.kernel.org, Matthew Wilcox <matthew@....cx>,
	Randy Dunlap <rdunlap@...otime.net>, linux-doc@...r.kernel.org
Subject: Re: [PATCH] Documentation: kernel-locking: mutex_trylock cannot be used in interrupt context

On Thu, 19 Aug 2010 07:38:15 am Stefan Richter wrote:
> Chapter 6 is right about mutex_trylock, but chapter 10 wasn't.
> This error was introduced during semaphore-to-mutex conversion of the
> Unreliable guide. :-)
> 
> If user context which performs mutex_lock() or mutex_trylock() is
> preempted by interrupt context which performs mutex_trylock() on the
> same mutex instance, a deadlock occurs.  This is because these functions
> do not disable local IRQs when they operate on mutex->wait_lock.

Acked-by: Rusty Russell <rusty@...tcorp.com.au>

I'm assuming Andrew Morton or Randy Dunlap will pick this up...

Thanks!
Rusty.
--
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/