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Re: Linux AMI 2011.09.1.x86_64-ebs issue: kernel aki-825ea7eb build-id munging
- From: Mark Wielaard <mjw at redhat dot com>
- To: "Frank Ch. Eigler" <fche at redhat dot com>
- Cc: gafton at amazon dot com, systemtap at sourceware dot org
- Date: Fri, 28 Oct 2011 00:56:30 +0200
- Subject: Re: Linux AMI 2011.09.1.x86_64-ebs issue: kernel aki-825ea7eb build-id munging
- References: <20111027205557.GA16686@redhat.com>
On Thu, 2011-10-27 at 16:55 -0400, Frank Ch. Eigler wrote:
> On the current default AMI
> kernel (22.214.171.124-95.38.amzn1.x86_64), there is a mismatch.
> One can see this by hex-dumping /sys/kernel/notes on a running instance,
> and contrasting it with
> % readelf -x .notes /usr/lib/debug/lib/modules/`uname -r`/vmlinux
> from the corresponding debuginfo. The last bunch of bytes are supposed
> to be identical.
> I seem to recall a kernel makefile (or perhaps elfutils) problem that
> resulted in a problem like this before. IIRC, it was some sort of problem
> during the vmlinux debuginfo stripping stage. Unfortunately, I can't find
> a link to the fix of the actual problem.
> cc:'ing our team to see if someone's memories can be jogged.
It doesn't immediately ring a bell [*].
Just to be sure. Does /sys/kernel/notes match
readelf -x .notes /boot/vmlinuz-`uname -r` ?
Is there anything else about /boot/vmlinuz-`uname -r`
vs /usr/lib/debug/lib/modules/`uname -r`/vmlinux that might indicate a
mismatch? Or does everything look fine if you just hack out the stap
[*] There was https://bugzilla.redhat.com/show_bug.cgi?id=590947
"debugedit vs modsign changes build ID", but that should only
impact kernel modules, not the vmlinuz image itself.