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    SubjectRe: UIO: phys_mem_access_prot() miss?
    On Tue, May 13, 2008 at 03:55:29PM +0200, Johann Baudy wrote:
    > Hi Hans, Greg,
    >
    > I need some help on UIO driver.
    > I have to add this below workaround (in uio.c) to be able to access
    > phys memory from user space.
    > I'm currently using PPC arch.
    > Am I wrong? or Is it a miss?
    >
    > static int uio_mmap(struct file *filep, struct vm_area_struct *vma)
    > {
    >
    > ...
    > switch (idev->info->mem[mi].memtype) {
    > case UIO_MEM_PHYS:
    > + vma->vm_page_prot = phys_mem_access_prot(filep,
    > + idev->info->mem[mi].addr >> PAGE_SHIFT,
    > + vma->vm_end - vma->vm_start,
    > + vma->vm_page_prot);
    > return uio_mmap_physical(vma);
    > case UIO_MEM_LOGICAL:
    > ...
    >
    > }
    >
    > FYI: I've copied those lines from mem char driver in mmap_mem().

    Hi Johann,
    what kernel are you using? Similar problems were reported before, and
    we've already applied a patch that should fix it. I think it hit
    mainline shortly before the 2.6.25 release. uio_mmap() should work with
    kernels >= 2.6.25 for PPC.

    Thanks,
    Hans



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