From mboxrd@z Thu Jan 1 00:00:00 1970 From: Konrad Rzeszutek Wilk Date: Mon, 03 Jan 2011 16:34:18 +0000 Subject: Re: [Xen-devel] Re: [patch] xenfb: fix xenfb suspend/resume race Message-Id: <20110103163418.GA14102@dumpdata.com> List-Id: References: <20101230125616.GA31537@joejin-pc.cn.oracle.com> <20101230164051.GC24313@dumpdata.com> <4D1D2A2D.80206@oracle.com> In-Reply-To: <4D1D2A2D.80206@oracle.com> MIME-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit To: Joe Jin Cc: jeremy@goop.org, xen-devel@lists.xensource.com, ian.campbell@citrix.com, gurudas.pai@oracle.com, guru.anbalagane@oracle.com, greg.marsden@oracle.com, linux-kernel@vger.kernel.org, linux-fbdev@vger.kernel.org, Andrew Morton > > I am unclear from your description whether the patch fixes > > the problem (I would presume so). Or does it take a long time > > to hit this race? > > > Yes, more than 100 migrations. we hit this issue around 3 times. OK, so you are still trying to find the culprit. Did you look at this patch from Ian: https://patchwork.kernel.org/patch/403192/ ? > > I dumped vmcore when guest crashed, from vmcore everything > looked good, fb_info, xenfb_info and so on. And the event channels are correct? .. snip.. > diff --git a/drivers/xen/events.c b/drivers/xen/events.c > index ac7b42f..4cfb5e2 100644 > --- a/drivers/xen/events.c > +++ b/drivers/xen/events.c > @@ -175,6 +175,8 @@ static struct irq_info *info_for_irq(unsigned irq) > > static unsigned int evtchn_from_irq(unsigned irq) > { > + if (unlikely(irq < 0 || irq >= nr_irqs)) > + return 0; You could insert a WARN_ON here to see see if you get this during your migration process. Or use xen_raw_printk in case the guest is hung for good. > return info_for_irq(irq)->evtchn; > } > > > _______________________________________________ > Xen-devel mailing list > Xen-devel@lists.xensource.com > http://lists.xensource.com/xen-devel