Re: [5.15] Please apply 'selftest/lkdtm: Skip stack-entropy test if lkdtm is not available'

[Greg KH]

On Fri, Feb 17, 2023 at 02:17:05PM -0800, Andrew Paniakin wrote:
> commit 90091c367e74d5b58d9ebe979cc363f7468f58d3 upstream.
> 
> This patch fixes the stack-entropy.sh test to exit gracefully when the LKDTM is
> not available. Test will hang otherwise as reported in [1].
> 
> Applicability of this fix to other LTS kernels:
> - 4.14: No lkdtm selftest
> - 4.19: No lkdtm selftest
> - 5.4:  No lkdtm selftests
> - 5.10: Inital selftest version introduced in 46d1a0f03d661 ("selftests/lkdtm:
>   Add tests for LKDTM targets") is a single script which has the LKDTM
>   availability check
> - 6.1: Fix applied
> 
> This patch applies cleanly to stable-5.15 tree. Updated test was executed in
> Qemu VM with different kernels:
> - CONFIG_LKDTM not enabled. Test finished with status SKIP.
> - CONFIG_LKDTM enabled. Test failed (but not hanged) with error 'Stack entropy
>   is low'.
> - CONFIG_LKDTM enabled and randomize_kstack_offset=on boot argument provided.
>   Test succeed.
> 
> [1] https://lore.kernel.org/lkml/2836f48a-d4e2-7f00-f06c-9f556fbd6332@xxxxxxxxxxxxxxxxxxx

Now queued up, thanks.

greg k-h