Re: [PATCH v6 07/12] x86/head_32.S: Define start_cpu0

["H. Peter Anvin" <hpa@zytor.com>]

Can you check how this interacts with tip:x86/realmode?

Fenghua Yu <fenghua.yu@intel.com> wrote:

>From: Fenghua Yu <fenghua.yu@intel.com>
>
>start_cpu0() is defined in head_32.S for 32-bit. The function sets up
>stack and
>jumps to start_secondary() for CPU0 wake up.
>
>Signed-off-by: Fenghua Yu <fenghua.yu@intel.com>
>---
> arch/x86/kernel/head_32.S |   12 ++++++++++++
> 1 files changed, 12 insertions(+), 0 deletions(-)
>
>diff --git a/arch/x86/kernel/head_32.S b/arch/x86/kernel/head_32.S
>index 463c979..a441303 100644
>--- a/arch/x86/kernel/head_32.S
>+++ b/arch/x86/kernel/head_32.S
>@@ -266,6 +266,18 @@ num_subarch_entries = (. - subarch_entries) / 4
> 	jmp default_entry
> #endif /* CONFIG_PARAVIRT */
> 
>+#ifdef CONFIG_HOTPLUG_CPU
>+/*
>+ * Boot CPU0 entry point. It's called from play_dead(). Everything has
>been set
>+ * up already except stack. We just set up stack here. Then call
>+ * start_secondary().
>+ */
>+ENTRY(start_cpu0)
>+	movl stack_start, %ecx
>+	movl %ecx, %esp
>+	jmp  *(initial_code)
>+#endif
>+
> /*
>  * Non-boot CPU entry point; entered from trampoline.S
>  * We can't lgdt here, because lgdt itself uses a data segment, but
>-- 
>1.6.0.3

-- 
Sent from my mobile phone. Please excuse brevity and lack of formatting.