Re: [RFC PATCH v3 00/22] arm64: livepatch: Use ORC for dynamic frame pointer validation

From: Madhavan T. Venkataraman
Date: Mon Mar 06 2023 - 13:14:23 EST




On 2/28/23 21:12, Tomohiro Misono (Fujitsu) wrote:
> <snip>
>> Testing
>> =======
>>
>> - I have run all of the livepatch selftests successfully. I have written a
>> couple of extra selftests myself which I will be posting separately
> Hi,
>
> What test configuration/environment you are using for test?
> When I tried kselftest with fedora based config on VM, I got errors
> because livepatch transition won't finish until signal is sent
> (i.e. it takes 15s for every transition).
>

Sorry for not responding earlier. I was out sick.

I tested on a bare metal system (thunderx) running Ubuntu. I will try to reproduce
the error you are seeing on a VM running fedora.

Madhavan

> [excerpt from test result]
> ```
> $ sudo ./test-livepatch.sh
> TEST: basic function patching ... not ok
>
> --- expected
> +++ result
> @@ -2,11 +2,13 @@
> livepatch: enabling patch 'test_klp_livepatch'
> livepatch: 'test_klp_livepatch': initializing patching transition
> livepatch: 'test_klp_livepatch': starting patching transition
> +livepatch: signaling remaining tasks
> livepatch: 'test_klp_livepatch': completing patching transition
> ```
>
> Thanks,
> Tomohiro
>
>>
>> - I have a test driver to induce a NULL pointer exception to make sure
>> that unwinding through exception handlers is reliable.
>>
>> - I use the test driver to create a timer to make sure that unwinding through
>> the timer IRQ is reliable.
>>
>> - I call the unwinder from different places during boot to make sure that
>> the unwinding in each of those cases is reliable.
>>