Can't load dtracedrv.ko; unknown symbols: ctf_init and ctf_exit

[msabramo]

I finally was able to build from the head of the github repo, but now I can't load the kernel module, dtracedrv.ko:

marca@ubuntu:~/src/dtrace4linux/newlinux$ make all
...
/home/marca/src/dtrace4linux/newlinux/build-2.6.32-38-generic/driver/vminfo.c:46: warning: 'sdt_add_locator' defined but not used
/home/marca/src/dtrace4linux/newlinux/build-2.6.32-38-generic/driver/vminfo.c:66: warning: 'vminfo_instr_callback' defined but not used
  CC [M]  /home/marca/src/dtrace4linux/newlinux/build-2.6.32-38-generic/driver/x_call.o
  CC [M]  /home/marca/src/dtrace4linux/newlinux/build-2.6.32-38-generic/driver/divmod64.o
  LD [M]  /home/marca/src/dtrace4linux/newlinux/build-2.6.32-38-generic/driver/dtracedrv.o
  Building modules, stage 2.
  MODPOST 1 modules
WARNING: "ctf_exit" [/home/marca/src/dtrace4linux/newlinux/build-2.6.32-38-generic/driver/dtracedrv.ko] undefined!
WARNING: "ctf_init" [/home/marca/src/dtrace4linux/newlinux/build-2.6.32-38-generic/driver/dtracedrv.ko] undefined!
  CC      /home/marca/src/dtrace4linux/newlinux/build-2.6.32-38-generic/driver/dtracedrv.mod.o
  LD [M]  /home/marca/src/dtrace4linux/newlinux/build-2.6.32-38-generic/driver/dtracedrv.ko
tools/mkctf.sh
-rw-r--r-- 1 marca marca 96284 Feb 29 14:45 build/linux-2.6.32-38-generic.ctf
sync
marca@ubuntu:~/src/dtrace4linux/newlinux$ sudo make load
tools/load.pl
14:47:50 Syncing...
14:47:50 Loading: build-2.6.32-38-generic/driver/dtracedrv.ko
insmod: error inserting 'build-2.6.32-38-generic/driver/dtracedrv.ko': -1 Unknown symbol in module

An error was detected loading the driver. Refer to
/var/log/messages or 'dmesg' to see what the issue
might be. For your convenience, here is the last few
lines from /var/log/messages:

===== tail -10 /var/log/messages
Feb 29 08:56:13 ubuntu kernel: [   99.802095] __ratelimit: 21 callbacks suppressed
Feb 29 08:56:13 ubuntu kernel: [   99.802098] type=1503 audit(1330534573.088:18):  operation="capable" pid=10204 parent=10200 profile="/usr/sbin/cupsd" name="sys_admin"
Feb 29 09:37:17 ubuntu kernel: [ 2560.567424] eth0: link down
Feb 29 09:37:28 ubuntu kernel: [ 2571.083710] eth0: link up
Feb 29 09:37:50 ubuntu kernel: [ 2593.050661] eth0: link down
Feb 29 09:38:00 ubuntu kernel: [ 2603.033176] eth0: link up
Feb 29 14:44:29 ubuntu kernel: [17366.909133] dtracedrv: module license 'CDDL' taints kernel.
Feb 29 14:44:29 ubuntu kernel: [17366.909153] Disabling lock debugging due to kernel taint
Feb 29 14:44:29 ubuntu kernel: [17366.909966] dtracedrv: Unknown symbol ctf_init
Feb 29 14:44:29 ubuntu kernel: [17366.910294] dtracedrv: Unknown symbol ctf_exit
make: *** [load] Error 1

I wonder is this is a side-effect of the change I made to replace the various .o files with libctf.a. Perhaps libctf.a doesn't have all of those object files...

[dtrace4linux]

yes - because of the missing driver/ctf*.c files, your solution picked the wrong files. The ctf stuff is confusing, but actually quite simple.

[msabramo]

I don't understand it yet. Perhaps someday I will. But at least we're making progress on getting everything to build more easily! :-)

[msabramo]

OK, I started off with a clean master. I still have to apply a680dfb to avoid issue #11 ("error: invalid storage class for function 'DEFINE_SEMAPHORE'"), but then the module builds and loads!

marca@ubuntu:~/src/dtrace4linux/newlinux$ sudo make load
tools/load.pl
15:03:48 Syncing...
15:03:48 Loading: build-2.6.32-38-generic/driver/dtracedrv.ko
15:03:49 Preparing symbols...
15:03:49 Probes available: 277007
15:03:51 Time: 3s