Re: kern/47041 (amd64 kernel core dumps are broken)

[Chuck Silvers <chuq%chuq.com@localhost>]

The following reply was made to PR kern/47041; it has been noted by GNATS.

From: Chuck Silvers <chuq%chuq.com@localhost>
To: Taylor R Campbell <campbell+netbsd%mumble.net@localhost>
Cc: gnats-bugs%NetBSD.org@localhost, kern-bug-people%netbsd.org@localhost,
        netbsd-bugs%netbsd.org@localhost, gnats-admin%netbsd.org@localhost
Subject: Re: kern/47041 (amd64 kernel core dumps are broken)
Date: Sat, 12 Jan 2013 08:33:16 -0800

 On Sat, Jan 12, 2013 at 08:56:52AM +0000, Taylor R Campbell wrote:
 > It's not clear to me whether this is just because the dump is bad or
 > because savecore is still broken, but when I tried to run savecore
 > after the last panic (unless I have mixed up panics in my memory,
 > which is entirely possible at this hour), it started off by saying
 > 
 > savecore: kvm_read: invalid translation (invalid level 3 PDE)
 > 
 > but proceeded to start writing a core dump to disk.  In the morning
 > (it's a 32 GB dump being written to a sync ffs) I'll see whether gdb
 > finds this core dump digestible.
 
 not all kvm_read errors are fatal for savecore, so your recollection
 could be correct.
 
 enabling machdep.sparse_dump=1 will help with large-memory systems.
 that should be working now as well.
 
 -Chuck