From b9b1a9c363ff7b17b2a35e20e28e86a449cfde1f Mon Sep 17 00:00:00 2001 From: Josh Poimboeuf Date: Wed, 21 Sep 2016 16:04:03 -0500 Subject: [PATCH] x86/boot/smp/32: Fix initial idle stack location on 32-bit kernels On 32-bit kernels, 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. Signed-off-by: Josh Poimboeuf Reviewed-by: Andy Lutomirski Cc: Borislav Petkov Cc: Brian Gerst Cc: Denys Vlasenko Cc: H. Peter Anvin Cc: Linus Torvalds Cc: Nilay Vaish Cc: Peter Zijlstra Cc: Thomas Gleixner Link: http://lkml.kernel.org/r/6cf569410bfa84cf923902fc4d628444cace94be.1474480779.git.jpoimboe@redhat.com Signed-off-by: Ingo Molnar --- 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 951f093a96fe..dcbd45ad8db6 100644 --- a/arch/x86/kernel/smpboot.c +++ b/arch/x86/kernel/smpboot.c @@ -964,9 +964,7 @@ 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; -- 2.30.2