On 2/26/25 7:07 AM, Niklas Schnelle wrote: > The s390 MMIO syscalls when using the classic PCI instructions do not > cause a page fault when follow_pfnmap_start() fails due to the page not > being present. Besides being a general deficiency this breaks vfio-pci's > mmap() handling once VFIO_PCI_MMAP gets enabled as this lazily maps on > first access. Fix this by following a failed follow_pfnmap_start() with > fixup_user_page() and retrying the follow_pfnmap_start(). Also fix > a VM_READ vs VM_WRITE mixup in the read syscall. > > Signed-off-by: Niklas Schnelle <schnelle@xxxxxxxxxxxxx> Reviewed-by: Matthew Rosato <mjrosato@xxxxxxxxxxxxx>
