RE: Follow-up to [Bug translator/14596] New: probe module enhancement request

["Chaiken, Alison" <Alison_Chaiken at mentor dot com>]

FChE:
Does the strace give a hint at where stap *is* looking for the
modules?  There should be a bunch of stat / openat / getdents type
syscalls.

Alison:
A gzipped version of the full output is attached.   In general, stap does seem to be looking in the correct sysroot, 
/build/meibp-2013/build/tmp/sysroots/mx6q.     It's not obvious to me where it's going wrong.   You'd be inclined to suspect the very last directory the script looks in

   [achaiken@sb-ubuntu-1204-64bit systemtap]$ ls /build/meibp-2013/build/tmp/sysroots/mx6q/usr/src/kernel/init
   do_mounts.h  Kconfig  Makefile

but that looks okay.   There is no reference to /lib/modules before the failure, hence my puzzlement.

FChE continues:
% stap <<<YOUR OTHER -r/-a/-B/etc. OPTIONS HERE>>> -L 'module("*").function("*")'

Alison:
This

    #!/bin/sh
    STAP_SYSROOT="/build/meibp-2013/build/tmp/sysroots"
    CROSS_COMPILE=arm-none-linux-gnueabi-

    ${STAP_SYSROOT}/x86_64-linux/usr/bin/stap -a arm \
		-R ${STAP_SYSROOT}/mx6q/usr/share/systemtap/runtime \
		--sysroot=${STAP_SYSROOT}/mx6q \
		-B CROSS_COMPILE=${CROSS_COMPILE} \
		-r ${STAP_SYSROOT}/mx6q/usr/src/kernel \
		-L 'module("*").function("*")' 

produces *no* output.  Hopefully that invocation is now what you intended!  I see that "man stap" says that -r should point to where /lib/modules/RELEASE/build is, but 
/build/meibp-2013/build/tmp/sysroots/mx6q/lib/modules/3.5.7.13-01716-g0e9463fa 
has no build directory:

    [achaiken@sb-ubuntu-1204-64bit systemtap]$ ls /build/meibp-2013/build/tmp/sysroots/mx6q/lib/modules   /3.5.7.13-01716-g0e9463fa/
    kernel/  modules.builtin  modules.order

Perhaps that then is the crux of the matter?

Version 1.6/0.152 is what is apparently packaged for Ubuntu 12.04 (which is our default VM runtime).    I can try and compile a newer version if you think that will solve the problem.

Thanks again,
Alison 
(who apologizes for using employer-mandated Outlook, but only as a web app running on $DEITY's Debian)

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