linux-kernel - Re: [RFC][PATCH 2/5] mm: Switch mod_state() to __this_cpu

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.DEB.2.00.1109191657150.19059@router.home>
Date:	Mon, 19 Sep 2011 17:02:13 -0500 (CDT)
From:	Christoph Lameter <cl@...two.org>
To:	Steven Rostedt <rostedt@...dmis.org>
cc:	linux-kernel@...r.kernel.org, Ingo Molnar <mingo@...e.hu>,
	Andrew Morton <akpm@...ux-foundation.org>,
	Thomas Gleixner <tglx@...utronix.de>,
	Peter Zijlstra <peterz@...radead.org>,
	Christoph Lameter <cl@...ux.com>
Subject: Re: [RFC][PATCH 2/5] mm: Switch mod_state() to __this_cpu_read()

On Mon, 19 Sep 2011, Steven Rostedt wrote:

> From: Steven Rostedt <srostedt@...hat.com>
>
> The code in mod_state() is already made to handle the raciness of
> this_cpu_read(). Have the code use __this_cpu_read() instead so
> the debug code does not trigger warnings about it.

Why would there be a warning triggered? this_cpu_read should take care of
disabling preemption for the read if needed. In fact the fallback case
does do exactly that.

I think it would make more sence if __this_cpu_read() could be made to
trigger a warning if used in context where preemption could be off.

--
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/