Re: [PATCH net-next v23 1/7] mm: page_frag: add a test module for page_frag

[Yunsheng Lin <yunshenglin0825@gmail.com>]

On 11/15/2024 10:12 PM, Mark Brown wrote:

...

> 
>> make -C tools/testing/selftests/livepatch/test_modules/
> 
> Ah, this one is actually using some framework support for building
> modules - it's putting the modules in a separate directory and using
> TEST_GEN_MODS_DIR.  Crucially, though, it has guards which ensure that
> we don't try to build the modules if KDIR doesn't exist - you should
> follow that pattern.

Will add a checking whether to build the test modules around the
TEST_GEN_MODS_DIR setup to avoid rsync copy error when the test module
compiling need to be skipped.

> 
>>> in the main kernel tree and enabled by the config file for the mm tests.
> 
>> As discussed in [1], this module is not really a vaild kernel module by
>> returning '-EAGAIN', which is the main reason that it is setup in the
>> selftests instead of the main kernel tree.
> 
> Sure, we have other test stuff in the main kernel.
> 
>> As above, I am not sure if there is some elegant way to avoid the above error
>> in the selftest core, one possible way to avoid the above error is to skip
>> compiling like below as tools/testing/selftests/mm/test_page_frag.sh already
>> skip the testing for page_frag if the test module is not compiled:
> 
> Since the tests currently don't build the test systems are by and by
> large not getting as far as trying to run anything, the entire mm suite
> is just getting skipped.

I just sent a fix for above, it would be good if you can test it if it
fixes the above problem.

I tested it with both latest net-next main kernel and older host kernel,
it seems to work.

1. 
https://lore.kernel.org/lkml/20241116042314.100400-1-yunshenglin0825@gmail.com/