xen/enlighten: Fix compile warnings and set cx to known value.

We get:
linux/arch/x86/xen/enlighten.c: In function ‘xen_start_kernel’:
linux/arch/x86/xen/enlighten.c:226: warning: ‘cx’ may be used uninitialized in this function
linux/arch/x86/xen/enlighten.c:240: note: ‘cx’ was declared here

and the cx is really not set but passed in the xen_cpuid instruction
which masks the value with returned masked_ecx from cpuid. This
can potentially lead to invalid data being stored in cx.

Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
This commit is contained in:
Konrad Rzeszutek Wilk 2011-09-29 13:06:42 -04:00
parent d98b15db37
commit 5e28783013

View File

@ -251,6 +251,7 @@ static void __init xen_init_cpuid_mask(void)
~((1 << X86_FEATURE_APIC) | /* disable local APIC */
(1 << X86_FEATURE_ACPI)); /* disable ACPI */
ax = 1;
cx = 0;
xen_cpuid(&ax, &bx, &cx, &dx);
xsave_mask =