From mboxrd@z Thu Jan 1 00:00:00 1970 From: Daniel De Graaf Subject: 2.6.37 dom0 under Xen 4.1 clocksource not working Date: Mon, 10 Jan 2011 10:06:19 -0500 Message-ID: <4D2B206B.3010707@tycho.nsa.gov> Mime-Version: 1.0 Content-Type: text/plain; charset=ISO-8859-1 Content-Transfer-Encoding: 7bit Return-path: List-Unsubscribe: , List-Post: List-Help: List-Subscribe: , Sender: xen-devel-bounces@lists.xensource.com Errors-To: xen-devel-bounces@lists.xensource.com To: xen-devel List-Id: xen-devel@lists.xenproject.org When booting 2.6.37 (from kernel.org) under Xen 4.1, there are apparently issues with timer interrupts being delivered to the dom0. Repeatedly causing an interrupt (for example, the ACPI power button) will allow the system to boot, as does adding "clocksource=jiffies" to the kernel command line. This is only present under Xen, not when booting the same kernel on real hardware. When boot with clocksource=jiffies, the system will sometimes freeze for about 30 seconds and then continue; however, this could be related to kernel debugging that I have enabled. The only clock-related message in dmesg is: [ 153.483813] Clocksource tsc unstable (delta = -77312555973 ns) /sys/devices/system/clocksource/clocksource0/available_clocksource: xen jiffies tsc I can attach kernel config or other information as required. I have observed this on at least two platforms; the 2.6.32.x xen kernels do not exhibit this behavior. -- Daniel De Graaf National Security Agency