From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from eggs.gnu.org ([2001:4830:134:3::10]:38353) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1bK6wq-0003kS-Lk for qemu-devel@nongnu.org; Mon, 04 Jul 2016 12:42:17 -0400 Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1bK6wm-0000zL-Th for qemu-devel@nongnu.org; Mon, 04 Jul 2016 12:42:15 -0400 Received: from mx1.redhat.com ([209.132.183.28]:54930) by eggs.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1bK6wm-0000zG-LP for qemu-devel@nongnu.org; Mon, 04 Jul 2016 12:42:12 -0400 Date: Mon, 4 Jul 2016 19:42:07 +0300 From: "Michael S. Tsirkin" Message-ID: <20160704194002-mutt-send-email-mst@redhat.com> References: <1466784366-281935-1-git-send-email-imammedo@redhat.com> <1466784366-281935-10-git-send-email-imammedo@redhat.com> <20160704171621-mutt-send-email-mst@redhat.com> <20160704181542.6c93db1d@172-15-182-60.lightspeed.austtx.sbcglobal.net> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20160704181542.6c93db1d@172-15-182-60.lightspeed.austtx.sbcglobal.net> Subject: Re: [Qemu-devel] [PATCH v2 09/18] pc: delay setting number of boot CPUs to machine_done time List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , To: Igor Mammedov Cc: qemu-devel@nongnu.org, pbonzini@redhat.com, rth@twiddle.net, ehabkost@redhat.com, armbru@redhat.com, eduardo.otubo@profitbricks.com, eblake@redhat.com, pkrempa@redhat.com, marcel@redhat.com On Mon, Jul 04, 2016 at 06:15:42PM +0200, Igor Mammedov wrote: > On Mon, 4 Jul 2016 17:17:51 +0300 > "Michael S. Tsirkin" wrote: > > > On Fri, Jun 24, 2016 at 06:05:57PM +0200, Igor Mammedov wrote: > > > currently present CPUs counter in CMOS only contains > > > smp_cpus (i.e. initial CPUs specified with -smp X) and > > > doesn't account for CPUs created with -device. > > > If VM is started with additional CPUs added with > > > -device, it will hang in BIOS waiting for condition > > > smp_cpus == counted_cpus > > > forever as counted_cpus will include -device CPUs as well > > > and be more than smp_cpus. > > > > > > make present CPUs counter in CMOS to count all CPUs > > > (initial and coldplugged with -device) by delaying > > > it to machine done time when it possible to count > > > CPUs added with -device. > > > > what if device_add from HMP is invoked after machine done > > but just before bios init? > > pc_cpu_plug(): > rtc_set_memory(pcms->rtc, 0x5f, rtc_get_memory(pcms->rtc, 0x5f) + 1); > > so BIOS will see and count CPU, the same as with cpu-add HMP command. It's all rather fragile. Can't we call above line for both hotpluggable and non-hotpluggable CPUs? > > > > > > > > Signed-off-by: Igor Mammedov > > > --- > > > hw/i386/pc.c | 12 +++++++++--- > > > 1 file changed, 9 insertions(+), 3 deletions(-) > > > > > > diff --git a/hw/i386/pc.c b/hw/i386/pc.c > > > index b4902f4..06c9de1 100644 > > > --- a/hw/i386/pc.c > > > +++ b/hw/i386/pc.c > > > @@ -471,9 +471,6 @@ void pc_cmos_init(PCMachineState *pcms, > > > rtc_set_memory(s, 0x5c, val >> 8); > > > rtc_set_memory(s, 0x5d, val >> 16); > > > > > > - /* set the number of CPU */ > > > - rtc_set_memory(s, 0x5f, smp_cpus - 1); > > > - > > > object_property_add_link(OBJECT(pcms), "rtc_state", > > > TYPE_ISA_DEVICE, > > > (Object **)&pcms->rtc, > > > @@ -1157,10 +1154,19 @@ void pc_cpus_init(PCMachineState *pcms) > > > static > > > void pc_machine_done(Notifier *notifier, void *data) > > > { > > > + int i, boot_cpus = 0; > > > PCMachineState *pcms = container_of(notifier, > > > PCMachineState, > > > machine_done); PCIBus *bus = pcms->bus; > > > > > > + for (i = 0; i < pcms->possible_cpus->len; i++) { > > > + if (pcms->possible_cpus->cpus[i].cpu) { > > > + boot_cpus++; > > > + } > > > + } > > > + /* set the number of CPUs */ > > > + rtc_set_memory(pcms->rtc, 0x5f, boot_cpus - 1); > > > + > > > if (bus) { > > > int extra_hosts = 0; > > > > > > -- > > > 1.8.3.1