1 files changed, 39 insertions, 0 deletions
diff --git a/system/xen/xsa/xsa333.patch b/system/xen/xsa/xsa333.patch
new file mode 100644
index 000000000000..6b86c942faa0
--- /dev/null
+++ b/system/xen/xsa/xsa333.patch
@@ -0,0 +1,39 @@
+From: Andrew Cooper <andrew.cooper3@citrix.com>
+Subject: x86/pv: Handle the Intel-specific MSR_MISC_ENABLE correctly
+
+This MSR doesn't exist on AMD hardware, and switching away from the safe
+functions in the common MSR path was an erroneous change.
+
+Partially revert the change.
+
+This is XSA-333.
+
+Fixes: 4fdc932b3cc ("x86/Intel: drop another 32-bit leftover")
+Signed-off-by: Andrew Cooper <andrew.cooper3@citrix.com>
+Reviewed-by: Jan Beulich <jbeulich@suse.com>
+Reviewed-by: Wei Liu <wl@xen.org>
+
+diff --git a/xen/arch/x86/pv/emul-priv-op.c b/xen/arch/x86/pv/emul-priv-op.c
+index efeb2a727e..6332c74b80 100644
+--- a/xen/arch/x86/pv/emul-priv-op.c
++++ b/xen/arch/x86/pv/emul-priv-op.c
+@@ -924,7 +924,8 @@ static int read_msr(unsigned int reg, uint64_t *val,
+         return X86EMUL_OKAY;
+ 
+     case MSR_IA32_MISC_ENABLE:
+-        rdmsrl(reg, *val);
++        if ( rdmsr_safe(reg, *val) )
++            break;
+         *val = guest_misc_enable(*val);
+         return X86EMUL_OKAY;
+ 
+@@ -1059,7 +1060,8 @@ static int write_msr(unsigned int reg, uint64_t val,
+         break;
+ 
+     case MSR_IA32_MISC_ENABLE:
+-        rdmsrl(reg, temp);
++        if ( rdmsr_safe(reg, temp) )
++            break;
+         if ( val != guest_misc_enable(temp) )
+             goto invalid;
+         return X86EMUL_OKAY;