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Date: Mon, 09 Jan 2012 01:25:31 -0800
From: Doug Barton <dougb@FreeBSD.org>
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Cc: arch@FreeBSD.org, Don Lewis <truckman@FreeBSD.org>, alfred@FreeBSD.org,
	adrian@FreeBSD.org
Subject: Re: [patch] allow crash dumps to Linux swap partitions
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On 01/09/2012 01:21, Nikos Vassiliadis wrote:
> On 1/9/2012 11:11 AM, Don Lewis wrote:
>> On  9 Jan, Adrian Chadd wrote:
>>> .. doesn't linux swap have some metadata somewhere?
>>
>> Darned if I know, but it doesn't seem to care about FreeBSD swap data
>> overwriting its swap partition.
> 
> Linux will not use the swap partition without the metadata. And
> these metadata are located to the start of the partition, that
> is, dumping core there will surely destroy them.

Actually I'm fairly confident that we write dumps backwards from the end
of the swap partition. It's done that way on purpose in case fsck'ing
causes the system to swap, it may still be possible to save the dump.


Doug

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