Re: [PATCH v4 4/4] selftest: Taint kernel when test module loaded

From: Luis Chamberlain
Date: Fri Jul 01 2022 - 18:33:45 EST


On Fri, Jul 01, 2022 at 04:47:44PM +0800, David Gow wrote:
> Make any kselftest test module (using the kselftest_module framework)
> taint the kernel with TAINT_TEST on module load.
>
> Note that several selftests use kernel modules which are not based on
> the kselftest_module framework, and so will not automatically taint the
> kernel.
>
> This can be done in two ways:
> - Moving the module to the tools/testing directory. All modules under
> this directory will taint the kernel.
> - Adding the 'test' module property with:
> MODULE_INFO(test, "Y")

This just needs to be documented somewhere other than a commit log.
Otherwise I am not sure how we can be sure it will catch on.

> Similarly, selftests which do not load modules into the kernel generally
> should not taint the kernel (or possibly should only do so on failure),
> as it's assumed that testing from user-space should be safe. Regardless,
> they can write to /proc/sys/kernel/tainted if required.
>
> Signed-off-by: David Gow <davidgow@xxxxxxxxxx>

Looks good otherwise!

Reviewed-by: Luis Chamberlain <mcgrof@xxxxxxxxxx>

Do we want this to go through selftest / kunit / modules tree?
Happy for it to through any. I can't predict a conflict.

Luis