[PATCH 011/104] KVM: Use standard CR3 flags, tighten checking

Avi Kivity
2007-09-17T08:30:53Z

From: Rusty Russell <rusty-8n+1lVoiYb80n/F98K4Iww@public.gmane.org>

The kernel now has asm/cpu-features.h: use those macros instead of inventing
our own.

Also spell out definition of CR3_RESEVED_BITS, fix spelling and
tighten it for the non-PAE case.

Signed-off-by: Rusty Russell <rusty-8n+1lVoiYb80n/F98K4Iww@public.gmane.org>
Signed-off-by: Avi Kivity <avi-atKUWr5tajBWk0Htik3J/w@public.gmane.org>
---
drivers/kvm/kvm.h | 9 +++------
drivers/kvm/kvm_main.c | 33 +++++++++++++++++++++------------
drivers/kvm/paging_tmpl.h | 2 +-
3 files changed, 25 insertions(+), 19 deletions(-)

diff --git a/drivers/kvm/kvm.h b/drivers/kvm/kvm.h
index 7117c3b..983c33f 100644
--- a/drivers/kvm/kvm.h
+++ b/drivers/kvm/kvm.h
@@ -19,12 +19,9 @@
#include <linux/kvm.h>
#include <linux/kvm_para.h>

-#define CR3_WPT_MASK (1ULL << 3)
-#define CR3_PCD_MASK (1ULL << 4)
-
-#define CR3_RESEVED_BITS 0x07ULL
-#define CR3_L_MODE_RESEVED_BITS (~((1ULL << 40) - 1) | 0x0fe7ULL)
-#define CR3_FLAGS_MASK ((1ULL << 5) - 1)
+#define CR3_PAE_RESERVED_BITS ((X86_CR3_PWT | X86_CR3_PCD) - 1)
+#define CR3_NONPAE_RESERVED_BITS ((PAGE_SIZE-1) & ~(X86_CR3_PWT | X86_CR3_PCD))
+#define CR3_L_MODE_RESERVED_BITS (CR3_NONPAE_RESERVED_BITS|0xFFFFFF0000000000ULL)

#define CR4_VME_MASK (1ULL << 0)
#define CR4_PSE_MASK (1ULL << 4)
diff --git a/drivers/kvm/kvm_main.c b/drivers/kvm/kvm_main.c
index 5d8febe..34a571d 100644
--- a/drivers/kvm/kvm_main.c
+++ b/drivers/kvm/kvm_main.c
@@ -571,23 +571,32 @@ EXPORT_SYMBOL_GPL(set_cr4);
void set_cr3(struct kvm_vcpu *vcpu, unsigned long cr3)
{
if (is_long_mode(vcpu)) {
- if (cr3 & CR3_L_MODE_RESEVED_BITS) {
+ if (cr3 & CR3_L_MODE_RESERVED_BITS) {
printk(KERN_DEBUG "set_cr3: #GP, reserved bits\n");
inject_gp(vcpu);
return;
}
} else {
- if (cr3 & CR3_RESEVED_BITS) {
- printk(KERN_DEBUG "set_cr3: #GP, reserved bits\n");
- inject_gp(vcpu);
- return;
- }
- if (is_paging(vcpu) && is_pae(vcpu) &&
- !load_pdptrs(vcpu, cr3)) {
- printk(KERN_DEBUG "set_cr3: #GP, pdptrs "
- "reserved bits\n");
- inject_gp(vcpu);
- return;
+ if (is_pae(vcpu)) {
+ if (cr3 & CR3_PAE_RESERVED_BITS) {
+ printk(KERN_DEBUG
+ "set_cr3: #GP, reserved bits\n");
+ inject_gp(vcpu);
+ return;
+ }
+ if (is_paging(vcpu) && !load_pdptrs(vcpu, cr3)) {
+ printk(KERN_DEBUG "set_cr3: #GP, pdptrs "
+ "reserved bits\n");
+ inject_gp(vcpu);
+ return;
+ }
+ } else {
+ if (cr3 & CR3_NONPAE_RESERVED_BITS) {
+ printk(KERN_DEBUG
+ "set_cr3: #GP, reserved bits\n");
+ inject_gp(vcpu);
+ return;
+ }
}
}

diff --git a/drivers/kvm/paging_tmpl.h b/drivers/kvm/paging_tmpl.h
index 4b5391c..01901ec 100644
--- a/drivers/kvm/paging_tmpl.h
+++ b/drivers/kvm/paging_tmpl.h
@@ -99,7 +99,7 @@ static int FNAME(walk_addr)(struct guest_walker *walker,
walker->table = kmap_atomic(pfn_to_page(hpa >> PAGE_SHIFT), KM_USER0);

ASSERT((!is_long_mode(vcpu) && is_pae(vcpu)) ||
- (vcpu->cr3 & ~(PAGE_MASK | CR3_FLAGS_MASK)) == 0);
+ (vcpu->cr3 & CR3_NONPAE_RESERVED_BITS) == 0);

walker->inherited_ar = PT_USER_MASK | PT_WRITABLE_MASK;