From 9baf8dbaac5707b25f9126a5ba06716efe6793d5 Mon Sep 17 00:00:00 2001 From: Miroslav Rezanina Date: Thu, 17 Oct 2013 10:38:42 +0200 Subject: [PATCH 05/25] target-i386: Set model=6 on qemu64 & qemu32 CPU models MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit Message-id: <1379363997-11783-2-git-send-email-ehabkost@redhat.com> Patchwork-id: 54398 O-Subject: [RHEL7 PATCH 1/4] target-i386: Set model=6 on qemu64 & qemu32 CPU models Bugzilla: 1004290 RH-Acked-by: Bandan Das RH-Acked-by: Markus Armbruster RH-Acked-by: Miroslav Rezanina Bugzilla: 1004290 Upstream status: commit f8e6a11aecc96e9d8a84f17d7c07019471714e20. Brew build: http://brewweb.devel.redhat.com/brew/taskinfo?taskID=6290888 There's no Intel CPU with family=6,model=2, and Linux and Windows guests disable SEP when seeing that combination due to Pentium Pro erratum #82. In addition to just having SEP ignored by guests, Skype (and maybe other applications) runs sysenter directly without passing through ntdll on Windows, and crashes because Windows ignored the SEP CPUID bit. So, having model > 2 is a better default on qemu64 and qemu32 for two reasons: making SEP really available for guests, and avoiding crashing applications that work on bare metal. model=3 would fix the problem, but it causes CPU enumeration problems for Windows guests[1]. So let's set model=6, that matches "Athlon (PM core)" on AMD and "P2 with on-die L2 cache" on Intel and it allows Windows to use all CPUs as well as fixing sysenter. [1] https://bugzilla.redhat.com/show_bug.cgi?id=508623 Cc: Andrea Arcangeli Signed-off-by: Eduardo Habkost Reviewed-by: Igor Mammedov Signed-off-by: Andreas Färber (cherry picked from commit 5cb6eb263d92972b54f84e0acf75e7159de20498) Signed-off-by: Eduardo Habkost Conflicts: include/hw/i386/pc.h Backport notes: * PC_COMPAT_1_6 does not exist on the RHEL-7 tree * RHEL-6 already have model=6 on qemu64 since RHEL-6.0, but not on qemu32, so PC_RHEL6_5_COMPAT includes only the qemu32 compat change Maintainer's notes: * Cherry-picked from Andreas Färber's qom-cpu tree * Upstream status valid for qemu tree --- hw/i386/pc_piix.c | 4 ++++ target-i386/cpu.c | 4 ++-- 2 files changed, 6 insertions(+), 2 deletions(-) --- hw/i386/pc_piix.c | 4 ++++ target-i386/cpu.c | 4 ++-- 2 files changed, 6 insertions(+), 2 deletions(-) diff --git a/hw/i386/pc_piix.c b/hw/i386/pc_piix.c index a19f155..39be127 100644 --- a/hw/i386/pc_piix.c +++ b/hw/i386/pc_piix.c @@ -861,6 +861,10 @@ static QEMUMachine pc_machine_rhel700 = { .property = "level",\ .value = stringify(0),\ },{\ + .driver = "qemu32-" TYPE_X86_CPU,\ + .property = "model",\ + .value = stringify(3),\ + },{\ .driver = "usb-ccid",\ .property = "serial",\ .value = "1",\ diff --git a/target-i386/cpu.c b/target-i386/cpu.c index a0358c0..170a46c 100644 --- a/target-i386/cpu.c +++ b/target-i386/cpu.c @@ -434,7 +434,7 @@ static x86_def_t builtin_x86_defs[] = { .level = 4, .vendor = CPUID_VENDOR_AMD, .family = 6, - .model = 2, + .model = 6, .stepping = 3, .features[FEAT_1_EDX] = PPRO_FEATURES | @@ -537,7 +537,7 @@ static x86_def_t builtin_x86_defs[] = { .level = 4, .vendor = CPUID_VENDOR_INTEL, .family = 6, - .model = 3, + .model = 6, .stepping = 3, .features[FEAT_1_EDX] = PPRO_FEATURES, -- 1.7.1