Re: [PATCH] Fix kunmap() argument in sg_miter_stop

Arjan van de Ven
2008-11-15T20:27:16Z

On Sat, 15 Nov 2008 20:15:15 +0000 (GMT)
Hugh Dickins <hugh@veritas.com> wrote:

> On Sat, 15 Nov 2008, Arjan van de Ven wrote:
> > >From fd5530ac75a919a20bf7951e90a2b12323e9c0a0 Mon Sep 17 00:00:00
> > >2001
> > From: Arjan van de Ven <arjan@linux.intel.com>
> > Date: Sat, 15 Nov 2008 11:23:58 -0800
> > Subject: [PATCH] Fix kunmap() argument in sg_miter_stop
> >
> > kunmap() takes as argument the struct page that orginally got
> > kmap()'d, however the sg_miter_stop() function passed it the kernel
> > virtual address instead, resulting in "kernel BUG at
> > arch/x86/mm/highmem_32.c:115!"
>
> Your patch looks like a good fix to me, but I don't get how its bug
> would manifest as highmem_32.c:115 - that's a check in
> kunmap_atomic(), whereas you're fixing a bad address to kunmap().
>

blarg

this is a new dimension to "off by one bug" L(

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