Attachment 157533 Details for Bug 245169 – xen-unstable c/s 15277 upstream accepted patch for solution

[patch] xen-unstable c/s 15277 upstream accepted patch for solution

xen_amd_to_vt_windows_bsod_15277.patch (text/plain), 1.99 KB, created by Tom Woller on 2007-06-21 13:47:03 UTC

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Creator: Tom Woller

Created: 2007-06-21 13:47:03 UTC

Size: 1.99 KB

patch

obsolete

># HG changeset patch
># User kfraser@localhost.localdomain
># Date 1181832897 -3600
># Node ID 912f7e312ec2a56c89ef5a949b6ecc72f5df74a6
># Parent  4d838167960694f1b9fcaec54590aef0e1f0a7ee
>hvm svm: Fix for BSOD when "migrating" from Intel to AMD.
>
>The Intel processor driver for Windows (XP and later at least) reads
>an MSR that AMD doesn't have. This causes GP-fault in kernel mode,
>which causes blue-screen-of-death on Windows. This prevents a
>disk-image that was installed on Intel from starting on an AMD
>processor.
>
>This patch "fixes" the problem by allowing reads from the msr,
>returning all zero's (which is a valid, if not particulary
>meaningful, value for this register).
>
>Signed-off-by: Mats Petersson <mats.petersson@amd.com>
>
>diff -r 4d8381679606 -r 912f7e312ec2 xen/arch/x86/hvm/svm/svm.c
>--- a/xen/arch/x86/hvm/svm/svm.c	Wed Jun 13 22:24:28 2007 +0100
>+++ b/xen/arch/x86/hvm/svm/svm.c	Thu Jun 14 15:54:57 2007 +0100
>@@ -2089,6 +2089,15 @@ static inline void svm_do_msr_access(
>             msr_content = 1ULL << 61; /* MC4_MISC.Locked */
>             break;
> 
>+        case MSR_IA32_EBC_FREQUENCY_ID:
>+            /*
>+             * This Intel-only register may be accessed if this HVM guest
>+             * has been migrated from an Intel host. The value zero is not
>+             * particularly meaningful, but at least avoids the guest crashing!
>+             */
>+            msr_content = 0;
>+            break;
>+
>         default:
>             if ( rdmsr_hypervisor_regs(ecx, &eax, &edx) ||
>                  rdmsr_safe(ecx, eax, edx) == 0 )
>diff -r 4d8381679606 -r 912f7e312ec2 xen/include/asm-x86/msr.h
>--- a/xen/include/asm-x86/msr.h	Wed Jun 13 22:24:28 2007 +0100
>+++ b/xen/include/asm-x86/msr.h	Thu Jun 14 15:54:57 2007 +0100
>@@ -96,6 +96,7 @@ static inline void wrmsrl(unsigned int m
> #define MSR_IA32_TIME_STAMP_COUNTER     0x10
> #define MSR_IA32_PLATFORM_ID		0x17
> #define MSR_IA32_EBL_CR_POWERON		0x2a
>+#define MSR_IA32_EBC_FREQUENCY_ID	0x2c
> 
> #define MSR_IA32_APICBASE		0x1b
> #define MSR_IA32_APICBASE_BSP		(1<<8)

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