From mboxrd@z Thu Jan  1 00:00:00 1970
From: Christian Borntraeger <borntraeger@de.ibm.com>
Subject: qemu core dump and filtering guest pages
Date: Tue, 22 May 2012 23:05:57 +0200
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Cc: Oleg Nesterov <oleg@redhat.com>
To: Avi Kivity <avi@redhat.com>, Marcelo Tosatti <mtosatti@redhat.com>,
	KVM list <kvm@vger.kernel.org>,
	Linux Kernel Mailing List <linux-kernel@vger.kernel.org>
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Folks,

today we discussed the situation of a qemu crash (with coredump) and big guests.
Quite often the guest pages are not needed but make the core file pretty big.

The most appealing proposal that we had was to adopt the core file code in the 
kernel to have an option for discarding guest pages (e.g. /proc/sys/core_guest).
do_corefile would have a callback into the kvm module that could use its memory 
slot infrastructure to decide if this page should be saved or not.

Would you consider such a change be ok? Any better idea?
Thanks

Christian