From mboxrd@z Thu Jan 1 00:00:00 1970 From: Ben Thomas Subject: Re: Re: xen hg tree from yesterda hangs when kernel console is directed to ttyS0 Date: Thu, 23 Mar 2006 13:36:31 -0500 Message-ID: <4422EAAF.50707@virtualiron.com> References: Mime-Version: 1.0 Content-Type: text/plain; charset=ISO-8859-1; format=flowed Content-Transfer-Encoding: 7bit Return-path: In-Reply-To: List-Unsubscribe: , List-Post: List-Help: List-Subscribe: , Sender: xen-devel-bounces@lists.xensource.com Errors-To: xen-devel-bounces@lists.xensource.com To: Keir Fraser Cc: xen-devel@lists.xensource.com List-Id: xen-devel@lists.xenproject.org Hi Keir, Thanks for the heads-up. I'll certainly give it a try. As this hang appears during boot, it's not clear how much reducing spinlock contention will help. At times, it's not even clear that I make it into __start_xen. Certainly, when I get a hang, I never make it out of __start_xen/init_e820/print_e820_memory_map. As it often stops in the middle of print_e820_memory_map output, that's what lead to the suspicion about serial lines. Clearly, though, it's merely a suspicion/guess. Thanks, -b Keir Fraser wrote: > In unstable changeset 9419 I've reduced contention for the serial-line > spinlock, particularly in the serial ISR. It certainly has cleaned up > some weird behaviour that I was able to reproduce when I hit the > serial line hard from within Xen itself. It's not clear it'll fix your > problems, but worth testing. > > -- Keir -- ------------------------------------------------------------------------ Ben Thomas Virtual Iron Software bthomas@virtualiron.com Tower 1, Floor 2 978-849-1214 900 Chelmsford Street Lowell, MA 01851