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Date: Wed, 07 Nov 2007 09:53:46 -0800
From: "H. Peter Anvin" <hpa@zytor.com>
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To: Yinghai Lu <yhlu.kernel@gmail.com>
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Subject: Re: pxeboot broken by commit "x86 setup: handle boot loaders which
 set up the stack incorrectly"
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Yinghai Lu wrote:
> 
> good to know. everyone need to update to 3.52 now...
> but i still can not understand why that mcp55 system works but the
> ck804 based doesn't on 3.10
> 

The bug is that syslinux incorrectly positions the stack above the 
command line (but not the stack pointer register; hence the kernel patch 
exposing this bug.)  So the stack plus command line end up being limited 
  to 512 bytes; how much stack gets used depends on the BIOS, so one 
BIOS may use a lot more than another.

	-hpa