From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from eggs.gnu.org ([2001:4830:134:3::10]:35626) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1bIg4p-0005ZH-Hq for qemu-devel@nongnu.org; Thu, 30 Jun 2016 13:48:38 -0400 Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1bIg4n-0006Iu-4X for qemu-devel@nongnu.org; Thu, 30 Jun 2016 13:48:34 -0400 Received: from mx1.redhat.com ([209.132.183.28]:42013) by eggs.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1bIg4m-0006Io-T3 for qemu-devel@nongnu.org; Thu, 30 Jun 2016 13:48:33 -0400 Received: from int-mx10.intmail.prod.int.phx2.redhat.com (int-mx10.intmail.prod.int.phx2.redhat.com [10.5.11.23]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mx1.redhat.com (Postfix) with ESMTPS id 7A311C05FBB3 for ; Thu, 30 Jun 2016 17:48:32 +0000 (UTC) Date: Thu, 30 Jun 2016 20:48:19 +0300 From: "Michael S. Tsirkin" Message-ID: <20160630204753-mutt-send-email-mst@redhat.com> References: <1467289387-47575-1-git-send-email-imammedo@redhat.com> <1467289387-47575-4-git-send-email-imammedo@redhat.com> <57751536.40003@redhat.com> <20160630150102.02954c68@nial.brq.redhat.com> <57751A90.9050902@redhat.com> MIME-Version: 1.0 Content-Type: text/plain; charset=utf-8 Content-Disposition: inline In-Reply-To: <57751A90.9050902@redhat.com> Content-Transfer-Encoding: quoted-printable Subject: Re: [Qemu-devel] [PATCH 3/4] acpi: provide _PXM method for CPU devices if QEMU is started numa enabled List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , To: Marcel Apfelbaum Cc: Igor Mammedov , qemu-devel@nongnu.org On Thu, Jun 30, 2016 at 04:11:44PM +0300, Marcel Apfelbaum wrote: > On 06/30/2016 04:01 PM, Igor Mammedov wrote: > > On Thu, 30 Jun 2016 15:48:54 +0300 > > Marcel Apfelbaum wrote: > >=20 > > > On 06/30/2016 03:23 PM, Igor Mammedov wrote: > > > > fixes long standing issue where Linux kernel would assing > > > > hotplugged CPU to 1st numa node as it discards proximity > > > > for hotplugged CPUs after SRAT is parsed. > > > >=20 > > > > Signed-off-by: Igor Mammedov > > > > --- > > > > hw/acpi/cpu.c | 9 +++++++++ > > > > 1 file changed, 9 insertions(+) > > > >=20 > > > > diff --git a/hw/acpi/cpu.c b/hw/acpi/cpu.c > > > > index c13b65c..d9cf3ee 100644 > > > > --- a/hw/acpi/cpu.c > > > > +++ b/hw/acpi/cpu.c > > > > @@ -4,6 +4,7 @@ > > > > #include "qapi/error.h" > > > > #include "qapi-event.h" > > > > #include "trace.h" > > > > +#include "sysemu/numa.h" > > > >=20 > > > > #define ACPI_CPU_HOTPLUG_REG_LEN 12 > > > > #define ACPI_CPU_SELECTOR_OFFSET_WR 0 > > > > @@ -503,6 +504,7 @@ void build_cpus_aml(Aml *table, MachineState = *machine, CPUHotplugFeatures opts, > > > >=20 > > > > /* build Processor object for each processor */ > > > > for (i =3D 0; i < arch_ids->len; i++) { > > > > + int j; > > > > Aml *dev; > > > > Aml *uid =3D aml_int(i); > > > > GArray *madt_buf =3D g_array_new(0, 1, 1); > > > > @@ -546,6 +548,13 @@ void build_cpus_aml(Aml *table, MachineState= *machine, CPUHotplugFeatures opts, > > > > aml_arg(1), aml_arg(2)) > > > > ); > > > > aml_append(dev, method); > > > > + > > > > + for (j =3D 0; j < nb_numa_nodes; j++) { > > > > + if (test_bit(i, numa_info[j].node_cpu)) { > > > > + aml_append(dev, aml_name_decl("_PXM", aml_in= t(j))); > > > > + } > > > > + } > > > > + > > > > aml_append(cpus_dev, dev); > > > > } > > > > } > > > >=20 > > >=20 > > > I would add, at least in the commit message, a pointer to the ACPI = spec: > > >=20 > > > ACPI 5.0 (6.2.13) > > > ----------------- > > > If the Local APIC ID / Local SAPIC ID / Local x2APIC ID of a dynami= cally added processor is not > > > present in the System Resource Affinity Table (SRAT), a _PXM object= must exist for the > > > processor=E2=80=99s device or one of its ancestors in the ACPI Name= space. > > >=20 > > >=20 > > > I suppose we don't have the APIC id in SRAT for all possible CPUs, = so it OK. > > we have entries for possible CPUs in SRAT and commit says that Linux = discards it, > > hence we need to add _PXM to CPU objects. So broken linux handling wo= uld put > > hotplugged CPUs into corrected nodes. > >=20 >=20 > OK, so the commit message was misleading: "Fixes" :) > Just flip "Fix" with "Workaround for... " >=20 > > To fix it on linux side, ACPI part probably would need to be refactor= ed to store > > parsed tables info somewhere else, so it would be available past boot= time > > (not a small undertaking) I'd say. >=20 > Maybe we should at least report it to the right mailing list. For sure, this can't hurt, but does not have to block this patch. >=20 > > While fixing it on QEMU side is easy and works well even for currentl= y released > > kernels. > >=20 >=20 > I have nothing against this approach. >=20 > Thanks, > Marcel >=20 > >=20 > > >=20 > > >=20 > > > Reviewed-by: Marcel Apfelbaum > > Thanks! > >=20 > > >=20 > > > Thanks, > > > Marcel > >=20