x86/hyperv: Use savesegment() instead of inline asm() to save segment registers

Use standard savesegment() utility macro to save segment registers.

Signed-off-by: Uros Bizjak <[email protected]>
Acked-by: Wei Liu <[email protected]>
Tested-by: Michael Kelley <[email protected]>
Cc: K. Y. Srinivasan <[email protected]>
Cc: Haiyang Zhang <[email protected]>
Cc: Dexuan Cui <[email protected]>
Cc: Thomas Gleixner <[email protected]>
Cc: Ingo Molnar <[email protected]>
Cc: Borislav Petkov <[email protected]>
Cc: Dave Hansen <[email protected]>
Cc: H. Peter Anvin <[email protected]>
Signed-off-by: Wei Liu <[email protected]>

Author: ubizjak

arch/x86/hyperv/ivm.c

@@ -25,6 +25,7 @@
 #include <asm/e820/api.h>
 #include <asm/desc.h>
 #include <asm/msr.h>
+#include <asm/segment.h>
 #include <uapi/asm/vmx.h>
 
 #ifdef CONFIG_AMD_MEM_ENCRYPT
@@ -315,16 +316,16 @@ int hv_snp_boot_ap(u32 apic_id, unsigned long start_ip, unsigned int cpu)
 	vmsa->gdtr.base = gdtr.address;
 	vmsa->gdtr.limit = gdtr.size;
 
-	asm volatile("movl %%es, %%eax;" : "=a" (vmsa->es.selector));
+	savesegment(es, vmsa->es.selector);
 	hv_populate_vmcb_seg(vmsa->es, vmsa->gdtr.base);
 
-	asm volatile("movl %%cs, %%eax;" : "=a" (vmsa->cs.selector));
+	savesegment(cs, vmsa->cs.selector);
 	hv_populate_vmcb_seg(vmsa->cs, vmsa->gdtr.base);
 
-	asm volatile("movl %%ss, %%eax;" : "=a" (vmsa->ss.selector));
+	savesegment(ss, vmsa->ss.selector);
 	hv_populate_vmcb_seg(vmsa->ss, vmsa->gdtr.base);
 
-	asm volatile("movl %%ds, %%eax;" : "=a" (vmsa->ds.selector));
+	savesegment(ds, vmsa->ds.selector);
 	hv_populate_vmcb_seg(vmsa->ds, vmsa->gdtr.base);
 
 	vmsa->efer = native_read_msr(MSR_EFER);