RE: [PATCH 11/20] vfio/cxl: Expose DPA memory region to userspace with fault+zap mmap

[Manish Honap]

> -----Original Message-----
> From: Dave Jiang <dave.jiang@xxxxxxxxx>
> Sent: 13 March 2026 22:38
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> Subject: Re: [PATCH 11/20] vfio/cxl: Expose DPA memory region to userspace
> with fault+zap mmap
> 
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> 
> On 3/11/26 1:34 PM, mhonap@xxxxxxxxxx wrote:
> > From: Manish Honap <mhonap@xxxxxxxxxx>
> < --snip-- >
> 
> > +int vfio_cxl_register_cxl_region(struct vfio_pci_core_device *vdev) {
> > +     struct vfio_pci_cxl_state *cxl = vdev->cxl;
> > +     u32 flags;
> > +     int ret;
> > +
> > +     if (!cxl)
> > +             return -ENODEV;
> > +
> > +     if (!cxl->region || cxl->region_vaddr)
> > +             return -ENODEV;
> > +
> > +     cxl->region_vaddr = ioremap_cache(cxl->region_hpa,
> > + cxl->region_size);
> 
> Should this be using memremap_pages() family of call rather than ioremap()
> like how DAX does it? CXL mem regions are not MMIO regions.
> 
> DJ

Okay, I will check the DAX code to update this part.