linux-kernel - Re: [ANNOUNCE] mdb: Merkey's Linux Kernel Debugger 2.6.27-rc4 released

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:	Thu, 21 Aug 2008 12:57:15 +0200
From:	Stefan Richter <stefanr@...6.in-berlin.de>
To:	Peter Zijlstra <peterz@...radead.org>
CC:	jmerkey@...fmountaingroup.com, linux-kernel@...r.kernel.org,
	Linus Torvalds <torvalds@...ux-foundation.org>,
	Nick Piggin <nickpiggin@...oo.com.au>,
	Paul E McKenney <paulmck@...ux.vnet.ibm.com>,
	David Howells <dhowells@...hat.com>
Subject: Re: [ANNOUNCE] mdb: Merkey's Linux Kernel Debugger 2.6.27-rc4	released

Peter Zijlstra wrote:
> On Wed, 2008-08-20 at 20:50 -0600, jmerkey@...fmountaingroup.com wrote:
> 
>>  volatiles left in the code due to the previously stated
>>  (and still present) severe breakage of the GNU compiler with SMP 
>>  shared data.  most of the barrier() functions are just plain broken
>>  and do not result in proper compiler behavior in this tree. 
> 
> Can you provide explicit detail?
> 
> By using barrier() the compiler should clobber all its memory and
> registers therefore forcing a write/reload of the variable.

I hope Jeff didn't try mere barrier()s only.  smp_wmb() and smp_rmb()
are the more relevant barrier variants for mdb, from what I remember
when I last looked at it.
-- 
Stefan Richter
-=====-==--- =--- =-=-=
http://arcgraph.de/sr/
--
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/