From mboxrd@z Thu Jan 1 00:00:00 1970 From: Sarah Newman Subject: Reproducible hang with cstate disabled Date: Thu, 12 Nov 2015 21:47:33 -0800 Message-ID: <56457975.6030007@prgmr.com> Mime-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Return-path: Received: from mail6.bemta5.messagelabs.com ([195.245.231.135]) by lists.xen.org with esmtp (Exim 4.72) (envelope-from ) id 1Zx7Cy-0002bY-6f for xen-devel@lists.xenproject.org; Fri, 13 Nov 2015 05:47:36 +0000 Received: from [192.168.1.3] (173-228-60-9.dsl.dynamic.fusionbroadband.com [173.228.60.9]) (Authenticated sender: srn) by mail.prgmr.com (Postfix) with ESMTPSA id 08A0C28C001 for ; Fri, 13 Nov 2015 00:47:33 -0500 (EST) List-Unsubscribe: , List-Post: List-Help: List-Subscribe: , Sender: xen-devel-bounces@lists.xen.org Errors-To: xen-devel-bounces@lists.xen.org To: xen-devel List-Id: xen-devel@lists.xenproject.org I saw xen hang after (XEN) HVM: HAP page sizes: 4kB, 2MB, 1GB ( The line that's supposed to be there is (XEN) Brought up 24 CPUs After power cycling I went into the BIOS. In the BIOS, C-STATE was disabled. I changed it to * Intel(R) C-STATE tech [Enabled] * C3 State [ACPI C2] * C6 State [Enabled] * C State package limit setting [Auto] * C1 Auto Demotion [Disabled] * C3 Auto Demotion [Disabled] After making the above changes it booted up correctly. I turned C-STATE off again and it hung at the same place. I turned C-STATE back on and it worked again. I have not tested on another machine yet, but I expect the same behavior. I'm using the latest official version from Xen4CentOS for CentOS 6: xen_major : 4 xen_minor : 4 xen_extra : .3-3.el6 xen_version : 4.4.3-3.el6 cc_compiler : gcc (GCC) 4.4.7 20120313 (Red Hat 4.4.7-16) cc_compile_by : mockbuild cc_compile_domain : centos.org cc_compile_date : Thu Oct 29 12:18:52 UTC 2015 Here are the rest of the CPU BIOS settings (left unchanged) * CPU Ratio [Auto] * C1E Support [Enabled] * Hardware Prefetcher [Enabled] * Adjacent Cache Line Prefetch [Enabled] * DCU Prefetcher [Enabled] * Data Reuse Optimization [Enabled] * MPS and ACPI MADT ordering [Modern ordering] * Intel(R) Virtualization Tech [Enabled] * Execute-Disable Bit Capability [Enabled] * Intel AES-NI [Enabled] * Simultaneous Multi-Threading [Enabled] * Active Processor Cores [All] * Intel(R) EIST Technology [Enabled] * Intel(R) Turbo Boost [Disabled] This is the CPU: Intel(R) Xeon(R) CPU L5640 CPUID :206C2 Microcode Rev :14 flags : fpu de tsc msr pae mce cx8 apic sep mca cmov pat clflush acpi mmx fxsr sse sse2 ss ht syscall nx lm constant_tsc rep_good nopl nonstop_tsc pni pclmulqdq monitor est ssse3 cx16 sse4_1 sse4_2 popcnt aes hypervisor lahf_lm ida arat epb dtherm Is this something that should be or has been fixed? If this was already fixed, can I have the commit ID so I can check if it's in the Xen4CentOS commit history? We have an idle machine with the same hardware if that helps with testing. Thanks, Sarah