[PATCH 5/9] x86/smp: fix initial idle stack location on 32-bit

[Josh Poimboeuf]

On 32-bit, the initial idle stack calculation doesn't take into account
the TOP_OF_KERNEL_STACK_PADDING, making the stack end address
inconsistent with other tasks on 32-bit.

Reviewed-by: Andy Lutomirski <l...@kernel.org>
Signed-off-by: Josh Poimboeuf <jpoim...@redhat.com>
---
 arch/x86/kernel/smpboot.c | 4 +---
 1 file changed, 1 insertion(+), 3 deletions(-)

diff --git a/arch/x86/kernel/smpboot.c b/arch/x86/kernel/smpboot.c
index 039790b..9345072 100644
--- a/arch/x86/kernel/smpboot.c
+++ b/arch/x86/kernel/smpboot.c
@@ -963,9 +963,7 @@ static int do_boot_cpu(int apicid, int cpu, struct 
task_struct *idle)
        int cpu0_nmi_registered = 0;
        unsigned long timeout;
 
-       idle->thread.sp = (unsigned long) (((struct pt_regs *)
-                         (THREAD_SIZE +  task_stack_page(idle))) - 1);
-
+       idle->thread.sp = (unsigned long)task_pt_regs(idle);
        early_gdt_descr.address = (unsigned long)get_cpu_gdt_table(cpu);
        initial_code = (unsigned long)start_secondary;
        initial_stack  = idle->thread.sp;
-- 
2.7.4