[Xen-devel] [PATCH v2 22/25] x86/hvm: Use guest_cpuid() rather than hvm_cpuid()

[Andrew Cooper <andrew.cooper3@xxxxxxxxxx>]

More work is required before maxphysaddr can be read straight out of the
cpuid_policy block, but in the meantime hvm_cpuid() wants to disappear so
update the code to use the newer interface.

Use the behaviour of max_leaf handling (returning all zeros) to avoid a double
call into guest_cpuid().

Signed-off-by: Andrew Cooper <andrew.cooper3@xxxxxxxxxx>
Reviewed-by: Jan Beulich <jbeulich@xxxxxxxx>
---
 xen/arch/x86/hvm/mtrr.c | 13 +++++--------
 1 file changed, 5 insertions(+), 8 deletions(-)

diff --git a/xen/arch/x86/hvm/mtrr.c b/xen/arch/x86/hvm/mtrr.c
index 228dac1..709759c 100644
--- a/xen/arch/x86/hvm/mtrr.c
+++ b/xen/arch/x86/hvm/mtrr.c
@@ -440,7 +440,7 @@ bool_t mtrr_fix_range_msr_set(struct domain *d, struct 
mtrr_state *m,
 bool_t mtrr_var_range_msr_set(
     struct domain *d, struct mtrr_state *m, uint32_t msr, uint64_t msr_content)
 {
-    uint32_t index, phys_addr, eax;
+    uint32_t index, phys_addr;
     uint64_t msr_mask;
     uint64_t *var_range_base = (uint64_t*)m->var_ranges;
 
@@ -453,13 +453,10 @@ bool_t mtrr_var_range_msr_set(
 
     if ( d == current->domain )
     {
-        phys_addr = 36;
-        hvm_cpuid(0x80000000, &eax, NULL, NULL, NULL);
-        if ( (eax >> 16) == 0x8000 && eax >= 0x80000008 )
-        {
-            hvm_cpuid(0x80000008, &eax, NULL, NULL, NULL);
-            phys_addr = (uint8_t)eax;
-        }
+        struct cpuid_leaf res;
+
+        guest_cpuid(current, 0x80000008, 0, &res);
+        phys_addr = (uint8_t)res.a ?: 36;
     }
     else
         phys_addr = paddr_bits;
-- 
2.1.4


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