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From: Roland McGrath <roland@redhat.com>
To: David Miller <davem@davemloft.net>
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Subject: Re: CONFIG_HAVE_ARCH_TRACEHOOK and you
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> > Didn't it also write NT_PRFPREG notes of the wrong size?
> 
> Yep, but gdb was "generous in what it received" and happily
> read the contents.

Ah.  I've always done core sanity checks with:
	1. generate core1 on old kernel
	2. generate core2 on new kernel (identical userland scenario)
	3. eu-readelf -nl core1 > a
	4. eu-readelf -nl core2 > b
	5. diff -u a b
Then you can eyeball any expected drift like SP address randomization,
and be suspicious of all other differences.  (Of course, I also test
that gdb still likes it.)


Thanks,
Roland