diff options
author | H. Peter Anvin <hpa@linux.intel.com> | 2011-02-04 16:14:11 -0800 |
---|---|---|
committer | H. Peter Anvin <hpa@zytor.com> | 2011-02-04 22:27:28 -0800 |
commit | 11d4c3f9b671720e80353dd7e433ff2bf65e9500 (patch) | |
tree | b3560b0642216e9c9e1a54e57a5f55845f063e6b /arch/x86/include/asm/smp.h | |
parent | f7448548a9f32db38f243ccd4271617758ddfe2c (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')
-rw-r--r-- | arch/x86/include/asm/smp.h | 5 |
1 files changed, 1 insertions, 4 deletions
diff --git a/arch/x86/include/asm/smp.h b/arch/x86/include/asm/smp.h index 4c2f63c7fc1b..1f4695136776 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); |