Re: [PATCH] selftests/rseq: Fix rseq for cases without glibc support

[Mathieu Desnoyers <mathieu.desnoyers@efficios.com>]

On 2025-01-14 09:07, Mathieu Desnoyers wrote:
> On 2025-01-13 18:06, Shuah Khan wrote:
>> On 12/10/24 15:44, Raghavendra Rao Ananta wrote:
>>> Currently the rseq constructor, rseq_init(), assumes that glibc always
>>> has the support for rseq symbols (__rseq_size for instance). However,
>>> glibc supports rseq from version 2.35 onwards. As a result, for the
>>> systems that run glibc less than 2.35, the global rseq_size remains
>>> initialized to -1U. When a thread then tries to register for rseq,
>>> get_rseq_min_alloc_size() would end up returning -1U, which is
>>> incorrect. Hence, initialize rseq_size for the cases where glibc doesn't
>>> have the support for rseq symbols.
>>>
>>> Cc: stable@vger.kernel.org
>>> Fixes: 73a4f5a704a2 ("selftests/rseq: Fix mm_cid test failure")
>>> Signed-off-by: Raghavendra Rao Ananta <rananta@google.com>
>>> ---
>>
>> Applied to linux_kselftest next for Linux 6.14-rc1 after fixing the
>> commit if for Fixes tag
> 
> Hi Shuah,
> 
> I did not review nor ack this patch. I need to review it carefully
> to make sure it does not break anything else moving forward.
> 
> Please wait before merging.

I am preparing an alternative fix which keeps the selftests
code in sync with librseq.

Thanks,

Mathieu

> 
> Thanks,
> 
> Mathieu
> 
>>
>> thanks,
>> -- Shuah
> 

-- 
Mathieu Desnoyers
EfficiOS Inc.
https://www.efficios.com