Commit 1ff80389 authored Dec 12, 2005 by Linus Torvalds

get_user_pages: don't try to follow PFNMAP pages



Nick Piggin points out that a few drivers play games with VM_IO (why?
who knows..) and thus a pfn-remapped area may not have that bit set even
if remap_pfn_range() set it originally.

So make it explicit in get_user_pages() that we don't follow VM_PFNMAP
pages, since pretty much by definition they do not have a "struct page"
associated with them.

Signed-off-by: Linus Torvalds <torvalds@osdl.org>

parent 14ee0a14

mm/memory.c

+1 −1

Original line number	Original line	Diff line number	Diff line
	@@ -1009,7 +1009,7 @@ int get_user_pages(struct task_struct tsk, struct mm_struct mm,
	continue;		continue;
	}		}

	if (!vma \|\| (vma->vm_flags & VM_IO)		if (!vma \|\| (vma->vm_flags & (VM_IO \| VM_PFNMAP))
	\|\| !(vm_flags & vma->vm_flags))		\|\| !(vm_flags & vma->vm_flags))
	return i ? : -EFAULT;		return i ? : -EFAULT;