diff options
| author | Kees Cook <kees.cook@canonical.com> | 2010-11-10 10:35:53 -0800 |
|---|---|---|
| committer | H. Peter Anvin <hpa@linux.intel.com> | 2010-11-10 15:43:09 -0800 |
| commit | ebba638ae723d8a8fc2f7abce5ec18b688b791d7 (patch) | |
| tree | 774eebadd4ca78e988e8ad029bca0d5e0e43f81c | |
| parent | ae84739c27b6b3725993202fe02ff35ab86468e1 (diff) | |
x86, cpu: Call verify_cpu during 32bit CPU startup
The XD_DISABLE-clearing side-effect needs to happen for both 32bit
and 64bit, but the 32bit init routines were not calling verify_cpu()
yet. This adds that call to gain the side-effect.
The longmode/SSE tests being performed in verify_cpu() need to happen very
early for 64bit but not for 32bit. Instead of including it in two places
for 32bit, we can just include it once in arch/x86/kernel/head_32.S.
Signed-off-by: Kees Cook <kees.cook@canonical.com>
LKML-Reference: <1289414154-7829-4-git-send-email-kees.cook@canonical.com>
Acked-by: Pekka Enberg <penberg@kernel.org>
Acked-by: Alan Cox <alan@lxorguk.ukuu.org.uk>
Signed-off-by: H. Peter Anvin <hpa@linux.intel.com>
| -rw-r--r-- | arch/x86/kernel/head_32.S | 6 | ||||
| -rw-r--r-- | arch/x86/kernel/verify_cpu.S | 1 |
2 files changed, 7 insertions, 0 deletions
diff --git a/arch/x86/kernel/head_32.S b/arch/x86/kernel/head_32.S index bcece91dd31..fdaea523ac8 100644 --- a/arch/x86/kernel/head_32.S +++ b/arch/x86/kernel/head_32.S @@ -314,6 +314,10 @@ ENTRY(startup_32_smp) subl $0x80000001, %eax cmpl $(0x8000ffff-0x80000001), %eax ja 6f + + /* Clear bogus XD_DISABLE bits */ + call verify_cpu + mov $0x80000001, %eax cpuid /* Execute Disable bit supported? */ @@ -609,6 +613,8 @@ ignore_int: #endif iret +#include "verify_cpu.S" + __REFDATA .align 4 ENTRY(initial_code) diff --git a/arch/x86/kernel/verify_cpu.S b/arch/x86/kernel/verify_cpu.S index ccb4136da0a..5644b4b7ed2 100644 --- a/arch/x86/kernel/verify_cpu.S +++ b/arch/x86/kernel/verify_cpu.S @@ -19,6 +19,7 @@ * * arch/x86_64/boot/compressed/head_64.S: Boot cpu verification * arch/x86_64/kernel/trampoline_64.S: secondary processor verfication + * arch/x86_64/kernel/head_32.S: processor startup * * verify_cpu, returns the status of longmode and SSE in register %eax. * 0: Success 1: Failure |