diff options
| author | Jeremy Fitzhardinge <jeremy.fitzhardinge@citrix.com> | 2009-09-21 13:34:06 -0700 |
|---|---|---|
| committer | Jeremy Fitzhardinge <jeremy.fitzhardinge@citrix.com> | 2009-09-21 13:49:43 -0700 |
| commit | b75fe4e5b869f8dbebd36df64a7fcda0c5b318ed (patch) | |
| tree | cba533110e8514184ddc63ab2ea37c38dc8a1861 | |
| parent | 79b520e87e1214cfa107bdc8528b5d6c055a8b82 (diff) | |
xen: check EFER for NX before setting up GDT mapping
x86-64 assumes NX is available by default, so we need to
explicitly check for it before using NX. Some first-generation
Intel x86-64 processors didn't support NX, and even recent systems
allow it to be disabled in BIOS.
[ Impact: prevent Xen crash on NX-less 64-bit machines ]
Signed-off-by: Jeremy Fitzhardinge <jeremy.fitzhardinge@citrix.com>
Cc: Stable Kernel <stable@kernel.org>
| -rw-r--r-- | arch/x86/mm/Makefile | 1 | ||||
| -rw-r--r-- | arch/x86/xen/enlighten.c | 10 |
2 files changed, 6 insertions, 5 deletions
diff --git a/arch/x86/mm/Makefile b/arch/x86/mm/Makefile index 9b5a9f59a478..dd313d035de7 100644 --- a/arch/x86/mm/Makefile +++ b/arch/x86/mm/Makefile @@ -4,6 +4,7 @@ obj-y := init.o init_$(BITS).o fault.o ioremap.o extable.o pageattr.o mmap.o \ # Make sure __phys_addr has no stackprotector nostackp := $(call cc-option, -fno-stack-protector) CFLAGS_physaddr.o := $(nostackp) +CFLAGS_init.o := $(nostackp) obj-$(CONFIG_SMP) += tlb.o diff --git a/arch/x86/xen/enlighten.c b/arch/x86/xen/enlighten.c index 0dd0c2c6cae0..5d701bf66a23 100644 --- a/arch/x86/xen/enlighten.c +++ b/arch/x86/xen/enlighten.c @@ -1083,6 +1083,11 @@ asmlinkage void __init xen_start_kernel(void) __supported_pte_mask |= _PAGE_IOMAP; +#ifdef CONFIG_X86_64 + /* Work out if we support NX */ + check_efer(); +#endif + xen_setup_features(); /* Get mfn list */ @@ -1123,11 +1128,6 @@ asmlinkage void __init xen_start_kernel(void) pgd = (pgd_t *)xen_start_info->pt_base; -#ifdef CONFIG_X86_64 - /* Work out if we support NX */ - check_efer(); -#endif - /* Don't do the full vcpu_info placement stuff until we have a possible map and a non-dummy shared_info. */ per_cpu(xen_vcpu, 0) = &HYPERVISOR_shared_info->vcpu_info[0]; |