Subject: Re: [PATCH] x86/boot: Support uncompressed kernel
To: Chao Peng <chao.p.peng@linux.intel.com>, Arnd Bergmann <arnd@arndb.de>,
        Michal Marek <mmarek@suse.com>
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Cc: Sebastian Andrzej Siewior <bigeasy@linutronix.de>,
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From: "H. Peter Anvin" <hpa@zytor.com>
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Date: Tue, 28 Mar 2017 15:38:49 -0700
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On 03/28/17 05:01, Chao Peng wrote:
>>
>> I guess the next step would be to use CONFIG_XIP_KERNEL on x86,
>> which requires an uncompressed kernel but has the additional advantage
>> of sharing the read-only sections of the kernel image across virtual
>> machines, resulting in better RAM and cache usage.
> 
> That is something we wanna look into :)
> 

It is, but that is a second order thing... especially since the x86
kernel makes heavy use of self-patching at the moment.  What would be
more significant, though, would be to avoid the memcpy() and instead
decode the uncompressed kernel in-place.

	-hpa