x86, realmode: read cr4 and EFER from kernel for 64-bit trampoline
This patch changes 64-bit trampoline so that CR4 and
EFER are provided by the kernel instead of using fixed
values.
Signed-off-by: Jarkko Sakkinen <jarkko.sakkinen@intel.com>
Link: http://lkml.kernel.org/r/1336501366-28617-24-git-send-email-jarkko.sakkinen@intel.com
Signed-off-by: H. Peter Anvin <hpa@linux.intel.com>
diff --git a/arch/x86/kernel/setup.c b/arch/x86/kernel/setup.c
index 7a14fec..efcf305 100644
--- a/arch/x86/kernel/setup.c
+++ b/arch/x86/kernel/setup.c
@@ -975,6 +975,8 @@
if (boot_cpu_data.cpuid_level >= 0) {
/* A CPU has %cr4 if and only if it has CPUID */
mmu_cr4_features = read_cr4();
+ if (trampoline_cr4_features)
+ *trampoline_cr4_features = mmu_cr4_features;
}
#ifdef CONFIG_X86_32