HEADS UP: Standalone kernel debug files moving out of /boot/kernel/

Garance A Drosehn drosih at rpi.edu
Thu Oct 30 17:50:23 UTC 2014

On 30 Oct 2014, at 12:49, Ed Maste wrote:

> On 30 October 2014 02:20, John-Mark Gurney <jmg at funkthat.com> wrote:
>> Oh, make sure that make install (or installkernel) properly handles
>> moving the debug data too... i.e. kernel to kernel.old...
> Yes, in the case that /boot/kernel is moved to /boot/kernel.old
> /usr/lib/debug/boot/kernel is moved to /usr/lib/debug/boot/kernel.old.

I definitely like the idea of moving the debug symbols out to /usr/lib/debug

I'm another person who sometimes has multiple kernels sitting in /boot
(which is one reason I'd like the debug symbols elsewhere!).  I may
shuffle those around by hand, and I'm sure I won't remember to shuffle
around information under /usr/lib/debug.  I also do things like
  cp -rp kernel kernel-PreBigChange
where I save away a copy of the kernel for possible fallback (at some
unknown future date), but I wouldn't need two copies of the debug info.

When we build a kernel, could we tag it with some unique-ID (by putting
that ID in a plain-text file inside the kernel's directory), and then
that unique-ID could be used for finding the correct debug info under
/usr/lib/debug?  This way we wouldn't need to move around any of the
debug info under /usr/lib/debug.  And we could tell which sets of
debug info should be removed by comparing the existing sets of debug
info with the kernel-unique-ID's which still exist under /boot.

If debug tools need to have the debug-info for the booted kernel to
be in a fixed location, then maybe the boot-up process could create
a symlink from some fixed pathname to the correct debug info for the
kernel which the system booted up on.

Garance Alistair Drosehn                =     drosih at rpi.edu
Senior Systems Programmer               or   gad at FreeBSD.org
Rensselaer Polytechnic Institute;             Troy, NY;  USA

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