On 1/19/2026 10:42 PM, Mukesh R wrote: > From: Mukesh Rathor <[email protected]> > > VFIO no longer puts the mmio pfn in vma->vm_pgoff. So, remove code > that is using it to map mmio space. It is broken and will cause > panic.
What is the reason for having this as a separate commit from patch 15? It seems like removing this code and adding the mmio intercept handling could be done in one patch. > > Signed-off-by: Mukesh Rathor <[email protected]> > --- > drivers/hv/mshv_root_main.c | 20 ++++---------------- > 1 file changed, 4 insertions(+), 16 deletions(-) > > diff --git a/drivers/hv/mshv_root_main.c b/drivers/hv/mshv_root_main.c > index 27313419828d..03f3aa9f5541 100644 > --- a/drivers/hv/mshv_root_main.c > +++ b/drivers/hv/mshv_root_main.c > @@ -1258,16 +1258,8 @@ static int mshv_prepare_pinned_region(struct > mshv_mem_region *region) > } > > /* > - * This maps two things: guest RAM and for pci passthru mmio space. > - * > - * mmio: > - * - vfio overloads vm_pgoff to store the mmio start pfn/spa. > - * - Two things need to happen for mapping mmio range: > - * 1. mapped in the uaddr so VMM can access it. > - * 2. mapped in the hwpt (gfn <-> mmio phys addr) so guest can access it. > - * > - * This function takes care of the second. The first one is managed by > vfio, > - * and hence is taken care of via vfio_pci_mmap_fault(). > + * This is called for both user ram and mmio space. The mmio space is not > + * mapped here, but later during intercept. > */ > static long > mshv_map_user_memory(struct mshv_partition *partition, > @@ -1276,7 +1268,6 @@ mshv_map_user_memory(struct mshv_partition *partition, > struct mshv_mem_region *region; > struct vm_area_struct *vma; > bool is_mmio; > - ulong mmio_pfn; > long ret; > > if (mem.flags & BIT(MSHV_SET_MEM_BIT_UNMAP) || > @@ -1286,7 +1277,6 @@ mshv_map_user_memory(struct mshv_partition *partition, > mmap_read_lock(current->mm); > vma = vma_lookup(current->mm, mem.userspace_addr); > is_mmio = vma ? !!(vma->vm_flags & (VM_IO | VM_PFNMAP)) : 0; > - mmio_pfn = is_mmio ? vma->vm_pgoff : 0; > mmap_read_unlock(current->mm); > > if (!vma) > @@ -1313,10 +1303,8 @@ mshv_map_user_memory(struct mshv_partition *partition, > HV_MAP_GPA_NO_ACCESS, NULL); > break; > case MSHV_REGION_TYPE_MMIO: > - ret = hv_call_map_mmio_pages(partition->pt_id, > - region->start_gfn, > - mmio_pfn, > - region->nr_pages); > + /* mmio mappings are handled later during intercepts */ > + ret = 0; > break; > } >
