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Subject: Re: [PATCH 1/2] kdump: Allow shrinking of kdump region to be
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From: Benjamin Herrenschmidt <benh@kernel.crashing.org>
To: "Eric W. Biederman" <ebiederm@xmission.com>
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Date: Thu, 24 Mar 2011 15:33:30 +1100
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Cc: linuxppc-dev@ozlabs.org, Anton Blanchard <anton@au1.ibm.com>,
	kexec@lists.infradead.org, linux-kernel@vger.kernel.org,
	WANG Cong <xiyou.wangcong@gmail.com>
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On Mon, 2011-03-21 at 03:10 +0000, WANG Cong wrote:
> On Tue, 15 Mar 2011 22:22:19 +0530, Mahesh J Salgaonkar wrote:

> >> Okay, but with this patch applied, we will just ignore rtas region,
> >> right?
> > Correct.
> >> Thus, when I echo 0 to free all the 128M crashkernel memory, the final
> >> result will be 32M left, which means crash_size will still show 32M.
> >> This looks odd.
> >> 
> >> How about skipping the 32M as a whole? I mean once the region being
> >> freed has overlap with this rtas region, skip the whole rtas region,
> >> and let crash_size
> >> show 0?
> > The existing code from crash_shrink_memory() function reduces the crash
> > size to 0 when echo'ed 0. I did test this patchset and verified that
> > /sys/kernel/kexec_crash_size show 0 value.
> 
> Oh, ok.
> 
> Acked-by: WANG Cong <xiyou.wangcong@gmail.com>

So Eric, what's the right approach to get that merged ? This is a bug
gating an important delivery for us, and the patch doesn't appear
terribly invasive ? :-)

I can send it to Linus myself if you prefer and give me your Ack.

Cheers,
Ben.