40 lines
1.3 KiB
Diff
40 lines
1.3 KiB
Diff
|
# Commit dfa625e15f3d6c374637f2bb789e1f444c2781c3
|
||
|
# Date 2014-08-22 14:29:37 +0200
|
||
|
# Author Jan Beulich <jbeulich@suse.com>
|
||
|
# Committer Jan Beulich <jbeulich@suse.com>
|
||
|
VMX: fix DebugCtl MSR clearing
|
||
|
|
||
|
The previous shortcut was wrong, as it bypassed the necessary vmwrite:
|
||
|
All we really want to avoid if the guest writes zero is to add the MSR
|
||
|
to the host-load list.
|
||
|
|
||
|
Signed-off-by: Jan Beulich <jbeulich@suse.com>
|
||
|
Reviewed-by: Andrew Cooper <andrew.cooper3@citrix.com>
|
||
|
Acked-by: Kevin Tian <kevin.tian@intel.com>
|
||
|
|
||
|
--- a/xen/arch/x86/hvm/vmx/vmx.c
|
||
|
+++ b/xen/arch/x86/hvm/vmx/vmx.c
|
||
|
@@ -2170,8 +2170,6 @@ static int vmx_msr_write_intercept(unsig
|
||
|
int i, rc = 0;
|
||
|
uint64_t supported = IA32_DEBUGCTLMSR_LBR | IA32_DEBUGCTLMSR_BTF;
|
||
|
|
||
|
- if ( !msr_content )
|
||
|
- break;
|
||
|
if ( msr_content & ~supported )
|
||
|
{
|
||
|
/* Perhaps some other bits are supported in vpmu. */
|
||
|
@@ -2191,12 +2189,10 @@ static int vmx_msr_write_intercept(unsig
|
||
|
}
|
||
|
|
||
|
if ( (rc < 0) ||
|
||
|
- (vmx_add_host_load_msr(msr) < 0) )
|
||
|
+ (msr_content && (vmx_add_host_load_msr(msr) < 0)) )
|
||
|
hvm_inject_hw_exception(TRAP_machine_check, 0);
|
||
|
else
|
||
|
- {
|
||
|
__vmwrite(GUEST_IA32_DEBUGCTL, msr_content);
|
||
|
- }
|
||
|
|
||
|
break;
|
||
|
}
|