linux-kernel - Re: NMI watchdog + NOHZ question

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: <20090624.001729.155964457.davem@davemloft.net>
Date:	Wed, 24 Jun 2009 00:17:29 -0700 (PDT)
From:	David Miller <davem@...emloft.net>
To:	andi@...stfloor.org
Cc:	linux-kernel@...r.kernel.org, sparclinux@...r.kernel.org
Subject: Re: NMI watchdog + NOHZ question

From: Andi Kleen <andi@...stfloor.org>
Date: Wed, 24 Jun 2009 09:15:55 +0200

> On Wed, Jun 24, 2009 at 12:08:11AM -0700, David Miller wrote:
>> From: Andi Kleen <andi@...stfloor.org>
>> Date: Wed, 24 Jun 2009 09:03:15 +0200
>> 
>> >> I'm not exactly sure what to do about this.
>> > 
>> > Ack the timer interrupt earlier (and also give it a high priority?)
>> 
>> It has a higher priority, but all interrupts get re-enabled right
>> before we process software interrupts.  So the flood of qla2xxx
>> interrupts can come in before we can run the timer softirq and
>> thus schedule the next timer interrupt.
> 
> Ah you have a one shot timer and it gets rescheduled in the softirq?
> If yes why not in doing that directly in the hardirq handler?

Then what's the point of the generic timer code supporting one-shot
clock sources? :-)
--
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/