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* Why do we reserve 8 bytes on top of the boot time stack?
@ 2016-01-29 13:00 Alexnader Kuleshov
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From: Alexnader Kuleshov @ 2016-01-29 13:00 UTC (permalink / raw)
  To: linux-kernel

Hello,

We reserve top 8 bytes of the boot stack in the arch/x86/kernel/head_64.S:

GLOBAL(stack_start)
.quad  init_thread_union+THREAD_SIZE-8

So, the question is in subject. Why? I've found definition of the
TOP_OF_KERNEL_STACK_PADDING macro arch/x86/include/asm/thread_info.h,
but it is zero for the x86_64.

Thank you.

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2016-01-29 13:00 Why do we reserve 8 bytes on top of the boot time stack? Alexnader Kuleshov

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