Re: [PATCH v2 0/2] riscv: mm: Avoid spurious fault after hotplugging vmemmap

[Mike Rapoport <rppt@kernel.org>]

On Thu, Jun 04, 2026 at 07:11:53PM +0800, Vivian Wang wrote:
> Patch 1 adds a hook and should be no functional change on its own,
> whereas patch 2 is the actual fix, which depends on my earlier kfence
> fixes for mark_new_valid_map() [1].
> 
> Found while testing AMD_HSA/ZONE_DEVICE on SpacemiT K3. Using
> ZONE_DEVICE requires another fix [2].
> 
> [1]: https://lore.kernel.org/linux-riscv/20260303-handle-kfence-protect-spurious-fault-v2-0-f80d8354d79d@iscas.ac.cn
> [2]: https://lore.kernel.org/linux-riscv/20260309-riscv-sparsemem-vmemmap-limits-v1-2-f40efe18e3cd@iscas.ac.cn
> 
> ---
> Changes in v2:
> - Split patch in two, hook point and riscv hook 

I don't think it should be split. You can add a hook and it's riscv
implementation in one patch, anyway this should go upstream via the same
tree.

> - Explain hook necessity in patch 1 message (Mike)
> - Make hook #define based (Mike)
> - Call finalize hook only on populate success
> - Link to v1: https://patch.msgid.link/20260525-mark-after-vmemmap-populate-v1-1-e698d859ba16@iscas.ac.cn
> 
> ---
> Vivian Wang (2):
>       mm/vmemmap: Add a post-population hook for architectures
>       riscv: mm: Avoid spurious fault after hotplugging vmemmap
> 
>  arch/riscv/include/asm/pgtable.h | 4 ++++
>  arch/riscv/mm/init.c             | 6 ++++++
>  mm/sparse-vmemmap.c              | 8 ++++++++
>  3 files changed, 18 insertions(+)
> ---
> base-commit: 254f49634ee16a731174d2ae34bc50bd5f45e731
> change-id: 20260525-mark-after-vmemmap-populate-68bd790839c9
> prerequisite-message-id: <20260303-handle-kfence-protect-spurious-fault-v2-0-f80d8354d79d@iscas.ac.cn>
> prerequisite-patch-id: fdc42f2647e21d111f44a6532887a6705cd470a9
> prerequisite-patch-id: 096fa339c84c36643ae4311fd8362dc63e23d950
> prerequisite-patch-id: 305c876a5f4a23a840a8142aea79b796ed297545
> prerequisite-patch-id: d78cb55d6a616b1170f06a401c8fd44acd11e5d5
> prerequisite-patch-id: b02b4a76e94f3e2821291d4c23b46f6e5ecf5203
> 
> Best regards,
> --  
> Vivian Wang <wangruikang@iscas.ac.cn>
> 

-- 
Sincerely yours,
Mike.