File 5f6a002d-x86-PV-handle-MSR_MISC_ENABLE-correctl... of Package xen

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File 5f6a002d-x86-PV-handle-MSR_MISC_ENABLE-correctly.patch of Package xen (Revision 5053153238d5d6a4ed0eadb71ca62ff8)

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# Commit e71301ecd50f2d3bd1b960bbf7dcf850d02e7e8a
# Date 2020-09-22 15:46:21 +0200
# Author Andrew Cooper <andrew.cooper3@citrix.com>
# Committer Jan Beulich <jbeulich@suse.com>
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>

--- a/xen/arch/x86/pv/emul-priv-op.c
+++ b/xen/arch/x86/pv/emul-priv-op.c
@@ -913,7 +913,8 @@ static int read_msr(unsigned int reg, ui
         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;
 
@@ -1053,7 +1054,8 @@ static int write_msr(unsigned int reg, u
         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;

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File 5f6a002d-x86-PV-handle-MSR_MISC_ENABLE-correctly.patch of Package xen (Revision 5053153238d5d6a4ed0eadb71ca62ff8)

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