[HVM][VMX] expose PSE feature to HVM guests if PAE is turned on in

config file, with this change, RHEL4 IA32 SMP guest can boot.
But because we don't support 4Mbytes PSE pages, so x86_32 HVM guest
can NOT use PSE feature. However user may have "pae=1" in config file,
which causes PSE feature seen by x86_32 HVM guest, and it will then use
4Mbytes PSE pages. In this case, we will have to crash x86_32 HVM.
So when running x86_32 HVM guest, user need pay attention not to have
"pae=1" in config file.

Signed-off-by: Xin Li <xin.b.li@intel.com>
Signed-off-by: Xiaohui Xin <xiaohui.xin@intel.com>

diff --git a/xen/arch/x86/hvm/vmx/vmx.c b/xen/arch/x86/hvm/vmx/vmx.c
index e40b76ecb5571e7d4b7f63eab8dfdb34775f6ee1..df2e295acb206d8c4399aad5ec3267728659e3bd 100644 (file)
--- a/xen/arch/x86/hvm/vmx/vmx.c
+++ b/xen/arch/x86/hvm/vmx/vmx.c
@@ -857,10 +857,14 @@ static void vmx_vmexit_do_cpuid(struct cpu_user_regs *regs)
 #else
             if ( v->domain->arch.ops->guest_paging_levels == PAGING_L2 )
             {
-                if ( !v->domain->arch.hvm_domain.pae_enabled )
+                if ( v->domain->arch.hvm_domain.pae_enabled )
+                    clear_bit(X86_FEATURE_PSE36, &edx);
+                else
+                {
                     clear_bit(X86_FEATURE_PAE, &edx);
-                clear_bit(X86_FEATURE_PSE, &edx);
-                clear_bit(X86_FEATURE_PSE36, &edx);
+                    clear_bit(X86_FEATURE_PSE, &edx);
+                    clear_bit(X86_FEATURE_PSE36, &edx);
+                }
             }
 #endif
 

diff --git a/xen/arch/x86/shadow.c b/xen/arch/x86/shadow.c
index d2a65f51df0225b9a6d369b6637a0df4d025a523..29895195fd0c17806acc114633f4a1c0479b1647 100644 (file)
--- a/xen/arch/x86/shadow.c
+++ b/xen/arch/x86/shadow.c
@@ -3724,7 +3724,13 @@ static inline int guest_page_fault(
     }
 
     if ( guest_l2e_get_flags(*gpl2e) & _PAGE_PSE )
+    {
+        printk("None-PAE HVM guests can NOT use PSE, "
+               "because we don't support 4MBytes PSE pages.\n");
+        printk("remove pae=1 from your config file.\n");
+        domain_crash_synchronous();
         return 0;
+    }
 
     __guest_get_l1e(v, va, gpl1e);