linux-kernel - Re: [PATCH] drivers/net/tile/: on-chip network drivers for the tile architecture

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: <1288806622.2511.187.camel@edumazet-laptop>
Date:	Wed, 03 Nov 2010 18:50:22 +0100
From:	Eric Dumazet <eric.dumazet@...il.com>
To:	Chris Metcalf <cmetcalf@...era.com>
Cc:	Stephen Hemminger <shemminger@...tta.com>,
	linux-kernel@...r.kernel.org, netdev@...r.kernel.org
Subject: Re: [PATCH] drivers/net/tile/: on-chip network drivers for the
 tile architecture

Le mercredi 03 novembre 2010 à 13:37 -0400, Chris Metcalf a écrit :
> Stephen, thanks for your feedback!
> 
> On 11/3/2010 12:59 PM, Stephen Hemminger wrote:
> > 1. MUST not use volatile, see volatile-considered-harmful.txt
> 
> The "harmful" use of volatile is in trying to fake out SMP.  Believe me,
> with a 64-core architecture, we know our SMP guidelines. :-)  Our use here
> is simply to force the compiler to issue a load, for the side-effect of
> populating the TLB, for example.
> 
> However, your response does suggest that simply the syntactic use of
> "volatile" will cause a red flag for readers.  I'll move this to an inline
> function in a header with a comment explaining what it's for, and use the
> function instead.

Please read Documentation/volatile-considered-harmful.txt

Then if there is a problem, we can make change to the documentation, but
volatile use in new code is _strictly_ forbidden.

ACCESS_ONCE() is your friend, we might document it in
Documentation/volatile-considered-harmful.txt



--
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/