Re: [patch 1/2] powerpc: Sky CPU: redundant or incorrect tests on unsigned

To All:
The sky cpu is a PPC7448.
I'm actually amazed that you guys are still working on a problem for a 
product that was finished a number of years ago, at the request of someone 
who hasn't worked here for years.
I sorry you, seem to have been wasting your time.
I think, but am NOT sure,  that our HAA function sets it off.
http://www.skycomputers.com/Systems/HAA_HMM.php

Still, we have finished the product some time ago, and as far as reported 
have no problems.
Again, I'm sorry you have wasted any time on this, we just recently found 
these emails.


Dave Bushee
Director OEM Sales and Services
SKY Computers Inc.
27 Industrial Ave.
978-250-2420 x232
www.skycomputers.com


----- Original Message ----- 
From: "Benjamin Herrenschmidt" <benh@kernel.crashing.org>
To: <akpm@linux-foundation.org>
Cc: <redacted>; <redacted>; 
[off-list ref]; [off-list ref]; [off-list ref]
Sent: Wednesday, February 03, 2010 6:21 PM
Subject: Re: [patch 1/2] powerpc: Sky CPU: redundant or incorrect tests on 
unsigned

On Tue, 2010-02-02 at 14:40 -0800, akpm@linux-foundation.org wrote:

quoted

From: Roel Kluin <redacted>

count is unsigned and cannot be less than 0.

Signed-off-by: Roel Kluin <redacted>
Acked-by: Cyrill Gorcunov <redacted>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Cc: Kumar Gala <redacted>
Cc: Brian Waite <redacted>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
---

I still have a hard time figuring out what this sky CPU actually is :-)

The whole drivers/misc/hdpuftrs is only built when CONFIG_HDPU_FEATURES
is set and git grep HDPU_FEATURES doesn't show anybody ever setting
it :-)

Is that just dead code ? I'm happy to carry it in powerpc.git if you
wish so but you it would be nice to figure out what's going on there...

Cheers,
Ben.

quoted

 drivers/misc/hdpuftrs/hdpu_cpustate.c |    5 -----
 1 file changed, 5 deletions(-)

diff -puN 
drivers/misc/hdpuftrs/hdpu_cpustate.c~powerpc-sky-cpu-redundant-or-incorrect-tests-on-unsigned 
drivers/misc/hdpuftrs/hdpu_cpustate.c
---  
a/drivers/misc/hdpuftrs/hdpu_cpustate.c~powerpc-sky-cpu-redundant-or-incorrect-tests-on-unsigned

+++ a/drivers/misc/hdpuftrs/hdpu_cpustate.c

@@ -121,8 +121,6 @@ static ssize_t cpustate_read(struct file
 {
 unsigned char data;

- if (count < 0)
- return -EFAULT;
 if (count == 0)
 return 0;

@@ -137,9 +135,6 @@ static ssize_t cpustate_write(struct fil
 {
 unsigned char data;

- if (count < 0)
- return -EFAULT;
-
 if (count == 0)
 return 0;

_