Re: [PATCH 1/5] pagemap: Modify add_to_pagemap to use copy_to_user instead of put_user.

["Thomas Tuttle" <ttuttle@google.com>]

On Thu, Jun 5, 2008 at 3:06 PM, Matt Mackall <mpm@selenic.com> wrote:
> On Thu, 2008-06-05 at 12:02 -0700, Andrew Morton wrote:
>> On Thu, 5 Jun 2008 11:04:21 -0400
>> "Thomas Tuttle" <ttuttle@google.com> wrote:
>>
>> > While fiddling with pagemap, I discovered a bug in add_to_pagemap.
>>
>> so...  afaict we have some fairly significant problems in here and a
>> version 2 of the patchset is in order?
>>
>> If so, when preparing that patchset please do have a think about which
>> of the fixes you believe should be backported into 2.6.25.x and prepare
>> the patches so that those fixes come first, to ease that backporting.
>
> For 2.6.25.x, we should probably just add a cast to the put_user dest.
> Thomas?

Okay, I've written a new patchset.  Patch 1/4 simply changes things to
use u64 pointers.  It's not that big a patch, but if you're really
uncomfortable backporting it, just stick a (u64*) before pm->out in
2.6.25.x.

Other than that, I don't believe any of the other fixes need to be
backported.  They just tweak a couple of things (error code on
unaligned reads, and which values show up in kpagecount), but don't
repair any particularly broken bits.

Please take a look at the new patchset and see if it fixes things to
your satisfaction.

--ttuttle