From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1755269AbYHXLs6 (ORCPT ); Sun, 24 Aug 2008 07:48:58 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1753032AbYHXLst (ORCPT ); Sun, 24 Aug 2008 07:48:49 -0400 Received: from py-out-1112.google.com ([64.233.166.181]:22307 "EHLO py-out-1112.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751850AbYHXLss (ORCPT ); Sun, 24 Aug 2008 07:48:48 -0400 DomainKey-Signature: a=rsa-sha1; c=nofws; d=gmail.com; s=gamma; h=message-id:date:from:to:subject:cc:in-reply-to:mime-version :content-type:content-transfer-encoding:content-disposition :references; b=XQLnOL9GWETAuh9SWk8U8acAQ1ErJZPIwuaPC37Jenh55W7VFnAlS1rXvUtqE2TptM NTRtK2r34jHVqFWLS2r/CsJAs90dNWI8+p0vX864bXtr1lbYjN5t/Lhx//OQhFGHxdXt XJ19hMNr70lvefK+z18clqHWB1oWgiFKIbLQ8= Message-ID: <19f34abd0808240448w5facaee2gec77662c14b9364f@mail.gmail.com> Date: Sun, 24 Aug 2008 13:48:47 +0200 From: "Vegard Nossum" To: "Mikael Pettersson" Subject: Re: [BUG] get_rtc_time() triggers NMI watchdog in hpet_rtc_interrupt() Cc: linux-kernel@vger.kernel.org, hpa@zytor.com, mingo@redhat.com, tglx@linutronix.de In-Reply-To: <18609.14516.873317.52292@harpo.it.uu.se> MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 7bit Content-Disposition: inline References: <200808230948.m7N9mUc1016360@harpo.it.uu.se> <19f34abd0808240214o22748804s45e8487d62b34cb8@mail.gmail.com> <18609.14516.873317.52292@harpo.it.uu.se> Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Sun, Aug 24, 2008 at 12:32 PM, Mikael Pettersson wrote: > > I also just got this during shutdown: > > > > Syncing hardware clock to system time BUG: NMI Watchdog detected > > LOCKUP on CPU0, ip c011d922, registers: > > Pid: 4181, comm: hwclock Not tainted (2.6.27-rc3-00464-g1fca254-dirty #42) [...] > See my reply in the thread following Ingo's patch > . I've only seen the lockup > while hwclock was setting or flushing the system time, so I suspect > broken interaction between the hpet rtc emulation and the rtc > user-space interface. Oops, I picked the wrong thread :-) Anyway, I guess it wouldn't be too hard to make a test cast by running "hwclock" (or the corresponding initscript) in a tight loop? (Sorry, I am not able to test this myself at the moment). That would make it easier to test the patch too, I guess. Maybe something like: $ while true; do /etc/init.d/ntpdate up; /etc/init.d/ntpdate down; done (At least "ntpdate" is the one that runs hwclock for me on F9.) I will try this later unless you beat me to it :-) Thanks, Vegard -- "The animistic metaphor of the bug that maliciously sneaked in while the programmer was not looking is intellectually dishonest as it disguises that the error is the programmer's own creation." -- E. W. Dijkstra, EWD1036