2.6.35-longterm review patch. If anyone has any objections, please let me know.
------------------ From: Bob Liu <lliu...@gmail.com> [ upstream commit 8f3b1327aa454bc8283e96bca7669c3c88b83f79 ] remap_pfn_range() means map physical address pfn<<PAGE_SHIFT to user addr. For nommu arch it's implemented by vma->vm_start = pfn << PAGE_SHIFT which is wrong acroding the original meaning of this function. And some driver developer using remap_pfn_range() with correct parameter will get unexpected result because vm_start is changed. It should be implementd like addr = pfn << PAGE_SHIFT but which is meanless on nommu arch, this patch just make it simply return. Parameter name and setting of vma->vm_flags also be fixed. Signed-off-by: Bob Liu <lliu...@gmail.com> Cc: Geert Uytterhoeven <ge...@linux-m68k.org> Cc: David Howells <dhowe...@redhat.com> Acked-by: Greg Ungerer <g...@uclinux.org> Cc: Mike Frysinger <vap...@gentoo.org> Cc: Bob Liu <lliu...@gmail.com> Cc: <sta...@kernel.org> Signed-off-by: Andrew Morton <a...@linux-foundation.org> Signed-off-by: Linus Torvalds <torva...@linux-foundation.org> Signed-off-by: Andi Kleen <a...@linux.intel.com> Index: linux-2.6.35.y/mm/nommu.c =================================================================== --- linux-2.6.35.y.orig/mm/nommu.c +++ linux-2.6.35.y/mm/nommu.c @@ -1747,10 +1747,13 @@ struct page *follow_page(struct vm_area_ return NULL; } -int remap_pfn_range(struct vm_area_struct *vma, unsigned long from, - unsigned long to, unsigned long size, pgprot_t prot) +int remap_pfn_range(struct vm_area_struct *vma, unsigned long addr, + unsigned long pfn, unsigned long size, pgprot_t prot) { - vma->vm_start = vma->vm_pgoff << PAGE_SHIFT; + if (addr != (pfn << PAGE_SHIFT)) + return -EINVAL; + + vma->vm_flags |= VM_IO | VM_RESERVED | VM_PFNMAP; return 0; } EXPORT_SYMBOL(remap_pfn_range); _______________________________________________ stable mailing list stable@linux.kernel.org http://linux.kernel.org/mailman/listinfo/stable