Re: exercising current aarch64 kprobe support with systemtap

[David Smith <dsmith@redhat.com>]

On 08/18/2016 10:16 AM, William Cohen wrote:
> On 08/18/2016 11:06 AM, David Smith wrote:
>> I'm not seeing any issue with fork in the testsuite results, but perhaps
>> I've missed something. What error are you referring to?
>>
> 
> Sorry,  I should have mentioned where I saw it.  The fork issues weren't in the syscall tests.  It was for procmod_wather.stp.  Below is the part of systemtap.log that shows the problem:
> 
> meta taglines 'test_check: stap -p4 procmod_watcher.stp' tag 'test_check' value 'stap -p4 procmod_watcher.stp'
> attempting command stap -p4 procmod_watcher.stp
> OUT semantic error: while resolving probe point: identifier 'nd_syscall' at procmod_watcher.stp:47:7
>         source: probe nd_syscall.fork.return {
>                       ^
> 
> semantic error: no match
> 
> Pass 2: analysis failed.  [man error::pass2]
> child process exited abnormally
> RC 1
> FAIL: systemtap.examples/process/procmod_watcher build
> meta taglines 'test_installcheck: stap procmod_watcher.stp -T 1' tag 'test_installcheck' value 'stap procmod_watcher.stp -T 1'
> UNTESTED: systemtap.examples/process/procmod_watcher run

Ah. That isn't really an aarch specific problem, lots of kernels
implement the C library fork() call with clone().

That's a problem with the procmod_watcher.stp example. I've updated it
to handle this problem (and another with exit()) in commit 543563e.

-- 
David Smith
dsmith@redhat.com
Red Hat
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