xen: mask out SEP from CPUID

Fix 32-on-64 pvops kernel: we don't want userspace using syscall/sysenter, even if the hypervisor supports it, so mask it out from CPUID. Signed-off-by: Jeremy Fitzhardinge <[email protected]> Signed-off-by: Ingo Molnar <[email protected]>
mna · Feb 29, 2008 · d40e705 · d40e705
1 parent 53c5858
commit d40e705
Showing 1 changed file with 1 addition and 0 deletions.
diff --git a/arch/x86/xen/enlighten.c b/arch/x86/xen/enlighten.c
@@ -153,6 +153,7 @@ static void xen_cpuid(unsigned int *ax, unsigned int *bx,
 	if (*ax == 1)
 		maskedx = ~((1 << X86_FEATURE_APIC) |  /* disable APIC */
 			    (1 << X86_FEATURE_ACPI) |  /* disable ACPI */
+			    (1 << X86_FEATURE_SEP)  |  /* disable SEP */
 			    (1 << X86_FEATURE_ACC));   /* thermal monitoring */
 
 	asm(XEN_EMULATE_PREFIX "cpuid"