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Date: Tue, 03 Aug 2010 13:09:05 -0700
From: Richard Henderson <rth@twiddle.net>
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Subject: Re: [Qemu-devel] [PATCH] loader: pad kernel size when loaded from
	a 	uImage
References: <1280454504-31224-1-git-send-email-hollis@penguinppc.org>	<1280454504-31224-2-git-send-email-hollis@penguinppc.org>	<20100730225641.GA20899@laped.lan>	<20100801123554.GA29468@laped.lan>	<AANLkTimd67rbQ=9fjAzhBNyRfyJD7AnhR3nUc3a+=+y+@mail.gmail.com>	<20100802185707.GA4527@laped.lan>	<AANLkTikT3wWKvmAzGOL1esHVkZrvuuYZbBjMpUvyZUdo@mail.gmail.com>	<20100802195645.GB4527@laped.lan>
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To: Hollis Blanchard <hollis@penguinppc.org>
Cc: "Edgar E. Iglesias" <edgar.iglesias@gmail.com>, qemu-devel@nongnu.org, kvm-ppc@vger.kernel.org

On 08/02/2010 01:35 PM, Hollis Blanchard wrote:
>> Of those archs, only 2 actually use the return value of load_uimage
>> to decide where to place blobs. PPC and MB. MB doesn't want any
>> magic applied to the return value. That leaves us with _ONE_ single
>> arch that needs magic that IMO is broken. You are trying to guess the
>> size of the loaded image's .bss area by adding a 16th of the uimage size?
> 
> Accounting for BSS hardly counts as "magic", I think. :)

A 1/16 factor is not "accounting", it's guessing i.e. magic.

I'm not sure why the u-image format doesn't include the size
of the bss, but my guess is that it's expecting the kernel to
zero its bss segment at startup.  File a bug with either the
kernel and/or the u-boot project if you like.


r~