From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1755645AbYE3PnM (ORCPT ); Fri, 30 May 2008 11:43:12 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1752642AbYE3Pm5 (ORCPT ); Fri, 30 May 2008 11:42:57 -0400 Received: from fg-out-1718.google.com ([72.14.220.155]:11325 "EHLO fg-out-1718.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752007AbYE3Pmz (ORCPT ); Fri, 30 May 2008 11:42:55 -0400 DomainKey-Signature: a=rsa-sha1; c=nofws; d=googlemail.com; s=gamma; h=message-id:date:from:user-agent:mime-version:to:cc:subject:content-type:content-transfer-encoding; b=h1mXNDnHwzIRkgcDpRwMWo4jvzYEseq31USCBuBzL7p3b+xSMDQEat1eyVvhMTIBOHHblhs44r0WluUELx01wuN/N8oyAjW4gzBEKH/ud5VVcbMX5zmgXRQ62AiwMx0Vv37F/j89liRmNBHsE1q0Z4QdiMBr3obp+DAFfWBtlN0= Message-ID: <48402064.6030400@googlemail.com> Date: Fri, 30 May 2008 17:42:28 +0200 From: Gabriel C User-Agent: Thunderbird 2.0.0.14 (X11/20080502) MIME-Version: 1.0 To: linux-next@vger.kernel.org CC: Linux Kernel list , Ingo Molnar , Thomas Gleixner Subject: linux-next: strange CPU calibration Content-Type: text/plain; charset=ISO-8859-1 Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Hi Ingo , Thomas , on 2.6.26-rc4-next-20080530 ( probably in earlier -next releases I didn't checked yet ) the CPU calibration is random wrong on my box with an Core2Quad CPU. The box is running x86_64 kernel. After rebooting the box ( using 'reboot command' ) from 2.6.25 to 2.6.26-rc4-next-20080530 I get : ... [4294014.566475] Calibrating delay using timer specific routine.. 5002.58 BogoMIPS (lpj=2501294) [4294014.586558] Calibrating delay using timer specific routine.. 2822.66 BogoMIPS (lpj=1411331) [4294014.668546] Calibrating delay using timer specific routine.. 2822.69 BogoMIPS (lpj=1411348) [4294014.751533] Calibrating delay using timer specific routine.. 2822.68 BogoMIPS (lpj=1411343) ... CPU0 is fine the other 3 cores wrong. ( full dmesg : http://frugalware.org/~crazy/next-calibration/2.6.26-rc4-next-20080530-dmesg_wrong_calibration_1 ) Now rebooting 2.6.26-rc4-next-20080530 -> 2.6.26-rc4-next-20080530 ( using shutdown -r now this time ) I get : ... [4294014.566476] Calibrating delay using timer specific routine.. 5002.57 BogoMIPS (lpj=2501288) [4294014.587558] Calibrating delay using timer specific routine.. 4999.71 BogoMIPS (lpj=2499858) [4294014.660547] Calibrating delay using timer specific routine.. 6899.61 BogoMIPS (lpj=3449809) [4294014.733536] Calibrating delay using timer specific routine.. 4999.73 BogoMIPS (lpj=2499865) ... CPU0 , CPU1 , CPU3 fine and CPU2 only wrong. ( full dmesg: http://frugalware.org/~crazy/next-calibration/2.6.26-rc4-next-20080530-dmesg_wrong_calibration_2 ) Finally when I halt the box wait a bit and power up again I get all right : ... [4294014.566475] Calibrating delay using timer specific routine.. 5002.60 BogoMIPS (lpj=2501300) [4294014.586558] Calibrating delay using timer specific routine.. 4999.71 BogoMIPS (lpj=2499855) [4294014.659547] Calibrating delay using timer specific routine.. 4999.73 BogoMIPS (lpj=2499865) [4294014.732536] Calibrating delay using timer specific routine.. 4999.73 BogoMIPS (lpj=2499867) ... ( full dmesg : http://frugalware.org/~crazy/next-calibration/2.6.26-rc4-next-20080530-dmesg_OK_after_halt ) config used for this kernel : http://frugalware.org/~crazy/next-calibration/next-config cpuinfo : processor : 0 vendor_id : GenuineIntel cpu family : 6 model : 23 model name : Intel(R) Core(TM)2 Quad CPU Q9300 @ 2.50GHz stepping : 7 cpu MHz : 2497.000 cache size : 3072 KB physical id : 0 siblings : 4 core id : 0 cpu cores : 4 apicid : 0 initial apicid : 0 fpu : yes fpu_exception : yes cpuid level : 10 wp : yes flags : fpu vme de pse tsc msr pae mce cx8 apic sep mtrr pge mca cmov pat pse36 clflush dts acpi mmx fxsr sse sse2 ss ht tm pbe syscall nx lm constant_tsc arch_perfmon pebs bts rep_good pni monitor ds_cpl vmx smx est tm2 ssse3 cx16 xtpr sse4_1 lahf_lm bogomips : 5002.60 clflush size : 64 cache_alignment : 64 address sizes : 36 bits physical, 48 bits virtual power management: processor : 1 vendor_id : GenuineIntel cpu family : 6 model : 23 model name : Intel(R) Core(TM)2 Quad CPU Q9300 @ 2.50GHz stepping : 7 cpu MHz : 2497.000 cache size : 3072 KB physical id : 0 siblings : 4 core id : 1 cpu cores : 4 apicid : 1 initial apicid : 1 fpu : yes fpu_exception : yes cpuid level : 10 wp : yes flags : fpu vme de pse tsc msr pae mce cx8 apic sep mtrr pge mca cmov pat pse36 clflush dts acpi mmx fxsr sse sse2 ss ht tm pbe syscall nx lm constant_tsc arch_perfmon pebs bts rep_good pni monitor ds_cpl vmx smx est tm2 ssse3 cx16 xtpr sse4_1 lahf_lm bogomips : 4999.71 clflush size : 64 cache_alignment : 64 address sizes : 36 bits physical, 48 bits virtual power management: processor : 2 vendor_id : GenuineIntel cpu family : 6 model : 23 model name : Intel(R) Core(TM)2 Quad CPU Q9300 @ 2.50GHz stepping : 7 cpu MHz : 2497.000 cache size : 3072 KB physical id : 0 siblings : 4 core id : 2 cpu cores : 4 apicid : 2 initial apicid : 2 fpu : yes fpu_exception : yes cpuid level : 10 wp : yes flags : fpu vme de pse tsc msr pae mce cx8 apic sep mtrr pge mca cmov pat pse36 clflush dts acpi mmx fxsr sse sse2 ss ht tm pbe syscall nx lm constant_tsc arch_perfmon pebs bts rep_good pni monitor ds_cpl vmx smx est tm2 ssse3 cx16 xtpr sse4_1 lahf_lm bogomips : 4999.73 clflush size : 64 cache_alignment : 64 address sizes : 36 bits physical, 48 bits virtual power management: processor : 3 vendor_id : GenuineIntel cpu family : 6 model : 23 model name : Intel(R) Core(TM)2 Quad CPU Q9300 @ 2.50GHz stepping : 7 cpu MHz : 2497.000 cache size : 3072 KB physical id : 0 siblings : 4 core id : 3 cpu cores : 4 apicid : 3 initial apicid : 3 fpu : yes fpu_exception : yes cpuid level : 10 wp : yes flags : fpu vme de pse tsc msr pae mce cx8 apic sep mtrr pge mca cmov pat pse36 clflush dts acpi mmx fxsr sse sse2 ss ht tm pbe syscall nx lm constant_tsc arch_perfmon pebs bts rep_good pni monitor ds_cpl vmx smx est tm2 ssse3 cx16 xtpr sse4_1 lahf_lm bogomips : 4999.73 clflush size : 64 cache_alignment : 64 address sizes : 36 bits physical, 48 bits virtual power management: I cannot reproduce this on linus tree ( I will do some more reboot and tests tomorrow against mainline tree just to be sure ). Please let me know if you need more informations. Best Regards, Gabriel