[PATCH 0/4] Fix a segmentation fault also add raid6test for RISC-V support

[Alexandre Ghiti]

On 7/10/25 03:44, Chunyan Zhang wrote:
> Hi Alex,
>
> On Wed, 9 Jul 2025 at 23:18, Alexandre Ghiti <alex at ghiti.fr> wrote:
>> Hi Chunyan,
>>
>> Patch 2 was merged via fixes, do you plan on resending a new version for
>> 6.17 that takes into account Palmer's remarks?
> Yes, I'm preparing the patches these days, just haven't figured out
> how to set NSIZE properly for user space.


Just use hwprobe() to make sure V is supported and then csr_read(VLENB) 
to retrieve this value, no?


>
> I probably should split the patchset, send out one today.
>
> Thanks,
> Chunyan
>
>> Thanks,
>>
>> Alex
>>
>> On 6/10/25 12:12, Chunyan Zhang wrote:
>>> The first two patches are fixes.
>>> The last two are for userspace raid6test support on RISC-V.
>>>
>>> The issue fixed in patch 2/4 was probably the same which was spotted by
>>> Charlie [1], I couldn't reproduce it at that time.
>>>
>>> When running raid6test in userspace on RISC-V, I saw a segmentation fault,
>>> I used gdb command to print pointer p, it was an unaccessible address.
>>>
>>> With patch 2/4, the issue didn't appear anymore.
>>>
>>> [1] https://lore.kernel.org/lkml/Z5gJ35pXI2W41QDk@ghost/
>>>
>>> Chunyan Zhang (4):
>>>     raid6: riscv: clean up unused header file inclusion
>>>     raid6: riscv: Fix NULL pointer dereference issue
>>>     raid6: riscv: Allow code to be compiled in userspace
>>>     raid6: test: add support for RISC-V
>>>
>>>    lib/raid6/recov_rvv.c   |  9 +-----
>>>    lib/raid6/rvv.c         | 62 +++++++++++++++++++++--------------------
>>>    lib/raid6/rvv.h         | 15 ++++++++++
>>>    lib/raid6/test/Makefile |  8 ++++++
>>>    4 files changed, 56 insertions(+), 38 deletions(-)
>>>