Re: [PATCH] selftest/livepatch: Only run test-kprobe with CONFIG_KPROBES_ON_FTRACE

[Joe Lawrence <joe.lawrence@redhat.com>]

On 3/17/25 14:59, Joe Lawrence wrote:
> On 3/17/25 12:51, Song Liu wrote:
>> CONFIG_KPROBES_ON_FTRACE is required for test-kprobe. Skip test-kprobe
>> when CONFIG_KPROBES_ON_FTRACE is not set.
>>
>> Signed-off-by: Song Liu <song@kernel.org>
>> ---
>>  tools/testing/selftests/livepatch/test-kprobe.sh | 2 ++
>>  1 file changed, 2 insertions(+)
>>
>> diff --git a/tools/testing/selftests/livepatch/test-kprobe.sh b/tools/testing/selftests/livepatch/test-kprobe.sh
>> index 115065156016..fd823dd5dd7f 100755
>> --- a/tools/testing/selftests/livepatch/test-kprobe.sh
>> +++ b/tools/testing/selftests/livepatch/test-kprobe.sh
>> @@ -5,6 +5,8 @@
>>  
>>  . $(dirname $0)/functions.sh
>>  
>> +zgrep KPROBES_ON_FTRACE /proc/config.gz || skip "test-kprobe requires CONFIG_KPROBES_ON_FTRACE"
>> +
> 
> Hi Song,
> 
> This in turn depends on CONFIG_IKCONFIG_PROC for /proc/config.gz (not
> set for RHEL distro kernels).
> 
> Is there a dynamic way to figure out CONFIG_KPROBES_ON_FTRACE support?
> Without looking into it very long, maybe test_klp_kprobe.c's call to
> register_kprobe() could fail with -ENOTSUPP and the test script could
> gracefully skip the test?
> 

Ugh, n/m, looking at the code now I see it already does return
-EOPNOTSUPP, but insmod throws out the code (if it even gets that far)
and so it only reports success or failure.  Graceful handling will have
to be more clever than that.

-- 
Joe