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Date: Tue, 25 Mar 2014 10:06:36 -0700
From: Chris Wright <chrisw@redhat.com>
To: Neil Horman <nhorman@tuxdriver.com>
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Cc: dev@dpdk.org, "H. Peter Anvin" <hpa@linux.intel.com>
Subject: Re: [dpdk-dev] [PATCH v4] eal_common_cpuflags: Fix %rbx corruption,
 and simplify the code
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* Neil Horman (nhorman@tuxdriver.com) wrote:

(given the format, I'd expect a From hpa here)

> Neil Horman reported that on x86-64 the upper half of %rbx would get
> clobbered when the code was compiled PIC or PIE, because the
> i386-specific code to preserve %ebx was incorrectly compiled.
> 
> However, the code is really way more complex than it needs to be.  For
> one thing, the CPUID instruction only needs %eax (leaf) and %ecx
> (subleaf) as parameters, and since we are testing for bits, we might
> as well list the bits explicitly.  Furthermore, we can use an array
> rather than doing a switch statement inside a structure.
> 
> Reported-by: Neil Horman <nhorman@tuxdriver.com>
> Signed-off-by: H. Peter Anvin <hpa@linux.intel.com>

And an S-o-B by you

(sorry for the otherwise content free nitpick)