From: Keir Fraser <keir.fraser@citrix.com>
Date: Mon, 26 Nov 2007 17:55:23 +0000 (+0000)
Subject: vmx realmode: Emulate writes to control registers.
X-Git-Tag: archive/raspbian/4.8.0-1+rpi1~1^2~14684^2~18
X-Git-Url: https://dgit.raspbian.org/?a=commitdiff_plain;h=8e5fe76bbcd721f08235f855b38a16cb0d8c4011;p=xen.git

vmx realmode: Emulate writes to control registers.
Signed-off-by: Keir Fraser <keir.fraser@citrix.com>
---

diff --git a/xen/arch/x86/hvm/vmx/realmode.c b/xen/arch/x86/hvm/vmx/realmode.c
index d26725ba00..dbd0711317 100644
--- a/xen/arch/x86/hvm/vmx/realmode.c
+++ b/xen/arch/x86/hvm/vmx/realmode.c
@@ -338,6 +338,36 @@ realmode_read_cr(
     return X86EMUL_OKAY;
 }
 
+static int
+realmode_write_cr(
+    unsigned int reg,
+    unsigned long val,
+    struct x86_emulate_ctxt *ctxt)
+{
+    switch ( reg )
+    {
+    case 0:
+        if ( !hvm_set_cr0(val) )
+            return X86EMUL_UNHANDLEABLE;
+        break;
+    case 2:
+        current->arch.hvm_vcpu.guest_cr[2] = val;
+        break;
+    case 3:
+        if ( !hvm_set_cr3(val) )
+            return X86EMUL_UNHANDLEABLE;
+        break;
+    case 4:
+        if ( !hvm_set_cr4(val) )
+            return X86EMUL_UNHANDLEABLE;
+        break;
+    default:
+        return X86EMUL_UNHANDLEABLE;
+    }
+
+    return X86EMUL_OKAY;
+}
+
 static int realmode_write_rflags(
     unsigned long val,
     struct x86_emulate_ctxt *ctxt)
@@ -412,6 +442,7 @@ static struct x86_emulate_ops realmode_emulator_ops = {
     .read_io       = realmode_read_io,
     .write_io      = realmode_write_io,
     .read_cr       = realmode_read_cr,
+    .write_cr      = realmode_write_cr,
     .write_rflags  = realmode_write_rflags,
     .wbinvd        = realmode_wbinvd,
     .cpuid         = realmode_cpuid,