path: root/arch/x86/include/asm/smp.h
diff options
authorH. Peter Anvin <hpa@linux.intel.com>2011-02-04 16:14:11 -0800
committerH. Peter Anvin <hpa@zytor.com>2011-02-04 22:27:28 -0800
commit11d4c3f9b671720e80353dd7e433ff2bf65e9500 (patch)
treeb3560b0642216e9c9e1a54e57a5f55845f063e6b /arch/x86/include/asm/smp.h
parentf7448548a9f32db38f243ccd4271617758ddfe2c (diff)
x86-32: Make sure the stack is set up before we use it
Since checkin ebba638ae723d8a8fc2f7abce5ec18b688b791d7 we call verify_cpu even in 32-bit mode. Unfortunately, calling a function means using the stack, and the stack pointer was not initialized in the 32-bit setup code! This code initializes the stack pointer, and simplifies the interface slightly since it is easier to rely on just a pointer value rather than a descriptor; we need to have different values for the segment register anyway. This retains start_stack as a virtual address, even though a physical address would be more convenient for 32 bits; the 64-bit code wants the other way around... Reported-by: Matthieu Castet <castet.matthieu@free.fr> LKML-Reference: <4D41E86D.8060205@free.fr> Tested-by: Kees Cook <kees.cook@canonical.com> Signed-off-by: H. Peter Anvin <hpa@linux.intel.com>
Diffstat (limited to 'arch/x86/include/asm/smp.h')
1 files changed, 1 insertions, 4 deletions
diff --git a/arch/x86/include/asm/smp.h b/arch/x86/include/asm/smp.h
index 4c2f63c7fc1..1f469513677 100644
--- a/arch/x86/include/asm/smp.h
+++ b/arch/x86/include/asm/smp.h
@@ -40,10 +40,7 @@ DECLARE_EARLY_PER_CPU(u16, x86_cpu_to_apicid);
DECLARE_EARLY_PER_CPU(u16, x86_bios_cpu_apicid);
/* Static state in head.S used to set up a CPU */
-extern struct {
- void *sp;
- unsigned short ss;
-} stack_start;
+extern unsigned long stack_start; /* Initial stack pointer address */
struct smp_ops {
void (*smp_prepare_boot_cpu)(void);