[PATCH][0/10] verify_area cleanup

[PATCH][0/10] verify_area cleanup

[Jesper Juhl]

Now that 2.6.11 is out the door it's time to try and submit this again.

The following patches convert all users of verify_area to access_ok and 
the final patch then deprecates verify_area acros all archs with the 
intention of removing it completely later. These patches get rid of 99+% 
of all users, there's still one or two macros left using it and there are 
still a few comments left refering to it that could be cleaned up - I'll 
get to those, but what remains after these patches is extremely little.

The reason for doing this is that verify_area is just a wrapper for 
access_ok anyway, so there's no good reason to keep it around - access_ok 
also seems more readable anyway with saner return values.

Since these patches touch things all over the tree the CC list would be 
enormous if I CC'd everyone involved on all patches, so I'll just CC this 
initial mail to a few key people I think are relevant (I hope I got that 
list right), and the actual patches I'll just send to linux-kernel and 
Andrew (or directly to people who ask for that).

I've split this into 10 patches like this :

[1] drivers part 1
	This patch cleans up the first half of drivers/

[2] drivers part 2
	This patch cleans up the second half of drivers/

[3] sound
	Cleans up everything in sound/

[4] i386 and misc.
	This cleans up arch/i386 plus kernel/ and a few other bits that 
	got left over from the other patches

[5] mips
	Everything in arch/mips
	
[6] ppc, ppc64, m68k, m68knommu
	ppc, ppc64, m68k and m68knommu cleanup are in this on

[7] sparc and sparc64
	Thi patch takes care of sparc and sparc64

[8] x86_64 and ia64
	cleanups for x86_64 and ia64 are in this patch

[9] misc remaining archs
	all remaining archs are cleaned up in one bunch by this patch
	
[10] deprecate
	This final patch deprecates verify_area across all archs.


I've been hoping that these could perhaps (after proper review of course) 
go into -mm to actually get some testing beyond what I'm able to do, so 
that maybe they could migrate into mainline within a release or two...

Speaking of testing, the changes in [4] are what affect my box here, so 
those I've been able to both build and boot. As for the rest, I've only 
been able to verify that a make of allyesconfig doesn't seem to have 
issues with these patches, but I don't have any way to actually boot test 
on anything but i386. But I think these patches are fairly low risk since 
the change from verify_area to access_ok is resonably simple in most 
cases.

I hope you will find the patches acceptable and I look forward to any 
feedback you might have.


-- 
Jesper Juhl

Re: [PATCH][0/10] verify_area cleanup

[William Lee Irwin III]

On Fri, Mar 04, 2005 at 03:47:07AM +0100, Jesper Juhl wrote:
> Now that 2.6.11 is out the door it's time to try and submit this again.
> The following patches convert all users of verify_area to access_ok and 
> the final patch then deprecates verify_area acros all archs with the 
> intention of removing it completely later. These patches get rid of 99+% 
> of all users, there's still one or two macros left using it and there are 
> still a few comments left refering to it that could be cleaned up - I'll 
> get to those, but what remains after these patches is extremely little.
> The reason for doing this is that verify_area is just a wrapper for 
> access_ok anyway, so there's no good reason to keep it around - access_ok 
> also seems more readable anyway with saner return values.
> Since these patches touch things all over the tree the CC list would be 
> enormous if I CC'd everyone involved on all patches, so I'll just CC this 
> initial mail to a few key people I think are relevant (I hope I got that 
> list right), and the actual patches I'll just send to linux-kernel and 
> Andrew (or directly to people who ask for that).

The execution at first glance appears good. Out of curiosity, does this
serve a larger purpose than eliminating a redundant API?


-- wli

Re: [PATCH][0/10] verify_area cleanup

[Jesper Juhl]

On Sun, 13 Mar 2005, William Lee Irwin III wrote:

> On Fri, Mar 04, 2005 at 03:47:07AM +0100, Jesper Juhl wrote:
> > Now that 2.6.11 is out the door it's time to try and submit this again.
> > The following patches convert all users of verify_area to access_ok and 
> > the final patch then deprecates verify_area acros all archs with the 
> > intention of removing it completely later. These patches get rid of 99+% 
> > of all users, there's still one or two macros left using it and there are 
> > still a few comments left refering to it that could be cleaned up - I'll 
> > get to those, but what remains after these patches is extremely little.
> > The reason for doing this is that verify_area is just a wrapper for 
> > access_ok anyway, so there's no good reason to keep it around - access_ok 
> > also seems more readable anyway with saner return values.
> > Since these patches touch things all over the tree the CC list would be 
> > enormous if I CC'd everyone involved on all patches, so I'll just CC this 
> > initial mail to a few key people I think are relevant (I hope I got that 
> > list right), and the actual patches I'll just send to linux-kernel and 
> > Andrew (or directly to people who ask for that).
> 
> The execution at first glance appears good. 

Thank you - Andrew found a few places where I'd messed up, but corrected 
those silently and merged the patches into -mm, so hopefully they can now 
get some proper testing.


>Out of curiosity, does this
> serve a larger purpose than eliminating a redundant API?
>
No, it's a redundant API and one that seems harder to get right (judging 
from all the comments about fixing up incorrect verify_area use all over 
the place) than acces_ok. That's the only reason for getting rid of it.


-- 
Jesper