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 for <linuxppc-dev@lists.ozlabs.org>; Fri, 26 Jul 2013 23:11:45 +1000 (EST)
Date: Fri, 26 Jul 2013 09:11:14 -0400
From: Neil Horman <nhorman@tuxdriver.com>
To: Anton Blanchard <anton@samba.org>
Subject: Re: [PATCH] module: ppc64 module CRC relocation fix causes perf issues
Message-ID: <20130726131114.GA11633@hmsreliant.think-freely.org>
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Cc: Rusty Russell <rusty@rustcorp.com.au>, linux-kernel@vger.kernel.org,
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On Fri, Jul 26, 2013 at 11:19:13AM +1000, Anton Blanchard wrote:
> 
> Hi Neil,
> 
> > Sorry I'm a bit late to the thread, I've ben swamped.  Has someone
> > tested this with kexec/kdump?  Thats why the origional patch was
> > created, because when kexec loads the kernel at a different physical
> > address, the relocations messed with the module crc's, and modules
> > couldn't load during the kexec boot.  Assuming that kernaddr_start
> > gets set appropriately during boot, using PHYSICAL_START should be
> > fine, but I wanted to check, and don't currently have access to a
> > powerpc system to do so. Neil
> 
> I tested a relocatable kernel forced to run at a non zero physical
> address (ie basically kdump). I verified CRCs were bad with your
> original patch backed out, and were good with this patch applied.
> 
> Anton
> 

Perfect, sounds like a sufficient test to me.

Acked-by: Neil Horman <nhorman@tuxdriver.com>