xen/22693-fam10-mmio-conf-base-protect.patch

# HG changeset patch
# User Keir Fraser <keir@xen.org>
# Date 1294648952 0
# Node ID 08bb0eefe87107c30a9bdc6d72f26b20c55ae687
# Parent  66e8062894641e5622aa6adc54297d5700b1cea3
x86-64: don't allow wrmsr to MSR_FAM10H_MMIO_CONF_BASE when Xen itself is using it

Signed-off-by: Jan Beulich <jbeulich@novell.com>

# HG changeset patch
# User Keir Fraser <keir@xen.org>
# Date 1294741846 0
# Node ID a2dcebb88bc4571d64b3f30c1fbb33cfe4f6e2c5
# Parent  1ae74f060a39ae1305b3a434d0faa1a19853fdab
x86-64: refine access permission check for wrmsr to MSR_FAM10H_MMIO_CONF_BASE

We really don't want the mmconf window to move/disappear whenever we
use is ourselves, not only when we enabled it.

Signed-off-by: Jan Beulich <jbeulich@novell.com>

Index: xen-4.0.2-testing/xen/arch/x86/traps.c
===================================================================
--- xen-4.0.2-testing.orig/xen/arch/x86/traps.c
+++ xen-4.0.2-testing/xen/arch/x86/traps.c
@@ -1716,6 +1716,10 @@ static int is_cpufreq_controller(struct
             (d->domain_id == 0));
 }
 
+#ifdef CONFIG_X86_64
+#include "x86_64/mmconfig.h"
+#endif
+
 static int emulate_privileged_op(struct cpu_user_regs *regs)
 {
     struct vcpu *v = current;
@@ -2275,7 +2279,13 @@ static int emulate_privileged_op(struct
                 goto fail;
             if ( !IS_PRIV(v->domain) )
                 break;
-            if ( (rdmsr_safe(MSR_FAM10H_MMIO_CONF_BASE, l, h) != 0) ||
+            if ( (rdmsr_safe(MSR_FAM10H_MMIO_CONF_BASE, l, h) != 0) )
+                goto fail;
+            if (
+#ifdef CONFIG_X86_64
+                 (pci_probe & PCI_PROBE_MASK) == PCI_PROBE_MMCONF ?
+                 eax != l || edx != h :
+#endif
                  (((((u64)h << 32) | l) ^ val) &
                   ~( FAM10H_MMIO_CONF_ENABLE |
                     (FAM10H_MMIO_CONF_BUSRANGE_MASK <<
Index: xen-4.0.2-testing/xen/arch/x86/x86_64/mmconfig.h
===================================================================
--- xen-4.0.2-testing.orig/xen/arch/x86/x86_64/mmconfig.h
+++ xen-4.0.2-testing/xen/arch/x86/x86_64/mmconfig.h
@@ -34,6 +34,8 @@
 
 #define PCI_VENDOR_ID_NVIDIA       0x10de
 
+extern unsigned int pci_probe;
+
 /*
  * AMD Fam10h CPUs are buggy, and cannot access MMIO config space
  * on their northbrige except through the * %eax register. As such, you MUST
Index: xen-4.0.2-testing/xen/arch/x86/x86_64/mmconfig-shared.c
===================================================================
--- xen-4.0.2-testing.orig/xen/arch/x86/x86_64/mmconfig-shared.c
+++ xen-4.0.2-testing/xen/arch/x86/x86_64/mmconfig-shared.c
@@ -24,7 +24,7 @@
 #include "mmconfig.h"
 
 static int __initdata known_bridge;
-static unsigned int pci_probe = PCI_PROBE_CONF1 | PCI_PROBE_MMCONF;
+unsigned int pci_probe = PCI_PROBE_CONF1 | PCI_PROBE_MMCONF;
 
 static void __init parse_mmcfg(char *s)
 {