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Tsirkin wrote: > > Signed-off-by: Kommula Shiva Shankar > > Acked-by: Jason Wang > > I also worry a bit about regressing on other hardware. > Cc nvidia guys. > > + vma->vm_page_prot = pgprot_noncached(vma->vm_page_prot); > > vm_flags_set(vma, VM_IO | VM_PFNMAP | VM_DONTEXPAND | VM_DONTDUMP); This is definitely required and correct if notify.addr comes from a PCI BAR address. You need to trace the origin of that memory in all the drivers to determine if it is OK or not. For instance mlx5 is: kick_addr = mdev->bar_addr + offset; res->phys_kick_addr = kick_addr; [..] addr = (phys_addr_t)ndev->mvdev.res.phys_kick_addr; "bar_addr" is PCI memory so this patch is correct and required for mlx5. ifcvf: hw->notify_base_pa = pci_resource_start(pdev, cap.bar) + le32_to_cpu(cap.offset); [..] hw->vring[i].notify_pa = hw->notify_base_pa + notify_off * hw->notify_off_multiplier; [..] area.addr = vf->vring[idx].notify_pa; octep: oct_hw->notify_base_pa = pci_resource_start(pdev, cap.bar) + le32_to_cpu(cap.offset); [..] oct_hw->vqs[i].notify_pa = oct_hw->notify_base_pa + notify_off * oct_hw->notify_off_multiplier; [..] area.addr = oct_hw->vqs[idx].notify_pa; pds: No idea, it is messed up though: area.addr = pdsv->vqs[qid].notify_pa; struct pds_vdpa_vq_info { dma_addr_t notify_pa; Can't cast dma_addr_t to phys_addr_t! virtio_pci: Also messed up: notify.addr = vp_vdpa->vring[qid].notify_pa; struct vp_vring { resource_size_t notify_pa; phys_addr is not a resource_size_t Guessing pds and virtio_pci are also both fine, even if I gave up trying to figure out where notify_pa gets set from in the end. So the patch is OK Reviewed-by: Jason Gunthorpe Jason