From mboxrd@z Thu Jan 1 00:00:00 1970 From: Jan Kiszka Subject: Re: [PATCH] cpu hotplug issue Date: Tue, 02 Aug 2011 12:24:19 +0200 Message-ID: <4E37D053.1050106@siemens.com> References: <20110720083507.GS2400@redhat.com> <20110721113342.GB3044@redhat.com> <4E281090.9070300@siemens.com> <20110721115118.GD3044@redhat.com> <20110721124512.GI3044@redhat.com> <4E29577A.9080909@siemens.com> <20110724115647.GR3044@redhat.com> <4E2C4434.1060106@web.de> <4E2D6D1B.8020903@siemens.com> <4E3193B9.5040407@siemens.com> Mime-Version: 1.0 Content-Type: text/plain; charset=ISO-8859-1 Content-Transfer-Encoding: 7bit Cc: Gleb Natapov , "kvm@vger.kernel.org" , Markus Armbruster To: Vasilis Liaskovitis Return-path: Received: from thoth.sbs.de ([192.35.17.2]:29831 "EHLO thoth.sbs.de" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1750939Ab1HBKY0 (ORCPT ); Tue, 2 Aug 2011 06:24:26 -0400 In-Reply-To: Sender: kvm-owner@vger.kernel.org List-ID: On 2011-08-02 11:46, Vasilis Liaskovitis wrote: > Hi, > > On Thu, Jul 28, 2011 at 6:52 PM, Jan Kiszka wrote: >> On 2011-07-27 18:35, Vasilis Liaskovitis wrote: >>> Hi, >>> >>> On Mon, Jul 25, 2011 at 3:18 PM, Jan Kiszka wrote: >>> Applying these 3 patches + hacks/fix on master doesn't solve the >>> initial "CPU: not responding" dmesg hotplug issue on my setup. >>> The ACPI event is delivered correctly, but "echo 1 > >>> /sys/devices/system/cpu/cpuX/online" still fails. >>> e.g. tested with "-smp 1,maxcpus=2" >>> >>> Could you share your qemu-kvm command line? >> >> Nothing special: >> >> qemu-system-x86_64 /my/image -m 1G -snapshot -smp 2,maxcpus=3 \ >> -cpu host,-kvmclock >> > > ok, I have tested the patched qemu-kvm (guestOS ubuntu 10.10 with > 2.6.35-24-generic kernel) with: > > qemu-system-x86_64 /my/image -m 1G -smp 1,maxcpus=2 \ > -cpu host,-kvmclock > > on 2 different physical hosts. On the first one: > > vendor_id : GenuineIntel > cpu family : 6 > model : 37 > model name : Intel(R) Core(TM) i3 CPU M 370 @ 2.40GHz > > cpu hotplug works ok. When onlining (echo 1 > > /sys/devices/system/cpu/cpu1/online) dmesg shows: > > Booting Node 0 Processor 1 APIC 0x1 > TSC synchronization [CPU#0 -> CPU#1]: > Measured 3573498937792 cycles TSC warp between CPUs, turning off TSC clock. > Marking TSC unstable due to check_tsc_sync_source failed > kvm-clock: cpu 1, msr 0:1f15901, secondary cpu clock Strange. Why does it still talk about kvm-clock? > > on the second system: > > vendor_id : AuthenticAMD > cpu family : 16 > model : 4 > model name : AMD Phenom(tm) II X4 955 Processor > > onlining fails: > > Booting Node 0 Processor 1 APIC 0x1 > CPU1: Not Responding. > > When I specify -kvmclock on the qemu command line for the AMD system, > it seems that the clocksource on the guest is hpet. > Dmesg on guest shows "Switching to clocksource hpet" and > /sys/devices/system/clocksource/clocksource0/current_clocksource > confirms. > > When I don't specify -kvmclock, then the guest clocksource is actually > kvm-clock. But the onlining problem persists. > > I have also tried a newer guestOS (debian-testing with 2.6.39 or 3.0.0 > kernel) on the second system, same problem. > > Also: what physical host have you used for testing? Intel(R) Core(TM) i7 CPU M 620 @ 2.67GHz FWIW, I've pushed my tree here: git://git.kiszka.org/qemu-kvm.git queues/cpu-hotplug Jan -- Siemens AG, Corporate Technology, CT T DE IT 1 Corporate Competence Center Embedded Linux