Re: Re: [PATCH] RISC-V: KVM: Remove automatic I/O mapping for VM_PFNMAP

[Anup Patel]

On Fri, Oct 24, 2025 at 7:01 PM <fangyu.yu@xxxxxxxxxxxxxxxxx> wrote:
>
> >> From: Fangyu Yu <fangyu.yu@xxxxxxxxxxxxxxxxx>
> >>
> >> As of commit aac6db75a9fc ("vfio/pci: Use unmap_mapping_range()"),
> >> vm_pgoff may no longer guaranteed to hold the PFN for VM_PFNMAP
> >> regions. Using vma->vm_pgoff to derive the HPA here may therefore
> >> produce incorrect mappings.
> >>
> >> Instead, I/O mappings for such regions can be established on-demand
> >> during g-stage page faults, making the upfront ioremap in this path
> >> is unnecessary.
> >>
> >> Fixes: 9d05c1fee837 ("RISC-V: KVM: Implement stage2 page table programming")
> >> Signed-off-by: Fangyu Yu <fangyu.yu@xxxxxxxxxxxxxxxxx>
> >
> >LGTM.
> >
> >Queued it as fix for Linux-6.18
> >
> >Reviewed-by: Anup Patel <anup@xxxxxxxxxxxxxx>
> >
> >Thanks,
> >Anup
> >
>
> Hi Anup:
>
> Thanks for the review.
>
> Please note that this patch has two build warnings, and I have fixed
> on patch V2:
> https://lore.kernel.org/linux-riscv/20251021142131.78796-1-fangyu.yu@xxxxxxxxxxxxxxxxx/
>

Can you send a separate patch with Fixes tag to this patch?

You can base the patch on riscv_kvm_next branch at:
https://github.com/kvm-riscv/linux.git

Regards,
Anup