From: Hugh Dickins The PageReserved removal in 2.6.15-rc1 prohibited get_user_pages on the areas flagged VM_RESERVED in place of PageReserved. That is correct in theory - we ought not to interfere with struct pages in such a reserved area; but in practice it broke BTTV for one. So revert to prohibiting only on VM_IO: if someone gets into trouble with get_user_pages on VM_RESERVED, it'll just be a "don't do that". You can argue that videobuf_mmap_mapper shouldn't set VM_RESERVED in the first place, but now's not the time for breaking drivers without notice. Signed-off-by: Hugh Dickins Signed-off-by: Andrew Morton --- mm/memory.c | 2 +- 1 files changed, 1 insertion(+), 1 deletion(-) diff -puN mm/memory.c~unpaged-get_user_pages-vm_reserved mm/memory.c --- 25/mm/memory.c~unpaged-get_user_pages-vm_reserved Thu Nov 17 14:36:14 2005 +++ 25-akpm/mm/memory.c Thu Nov 17 14:36:14 2005 @@ -968,7 +968,7 @@ int get_user_pages(struct task_struct *t continue; } - if (!vma || (vma->vm_flags & (VM_IO | VM_RESERVED)) + if (!vma || (vma->vm_flags & VM_IO) || !(vm_flags & vma->vm_flags)) return i ? : -EFAULT; _