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, 6 Feb 2014 09:56:54 -0800
From:	Linus Torvalds <torvalds@...ux-foundation.org>
To:	Peter Zijlstra <peterz@...radead.org>
Cc:	"linux-arch@...r.kernel.org" <linux-arch@...r.kernel.org>,
	Linux Kernel Mailing List <linux-kernel@...r.kernel.org>,
	Andrew Morton <akpm@...ux-foundation.org>,
	Ingo Molnar <mingo@...nel.org>,
	Will Deacon <will.deacon@....com>,
	Paul McKenney <paulmck@...ux.vnet.ibm.com>
Subject: Re: [RFC][PATCH 5/5] arch: Sanitize atomic_t bitwise ops

On Thu, Feb 6, 2014 at 9:52 AM, Peter Zijlstra <peterz@...radead.org> wrote:
>
> s390 is stuffed with atomic_{set,clear}_mask usage, no clue whatfor.

It's not the set/clear_mask ones I would worry about.

It's the "_return" variants. As far as I can tell, there are exactly
ZERO users of that stuff, and they are BAD BAD BAD.

On x86, those things would cause a cmpxchg loop, and the bad
read-for-shared-before-acquire cacheline pattern.

So why indirectly encourage people to add users for a bad operation?

                        Linus
--
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