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

Submitted by Andrew Morton on Feb. 2, 2010, 10:40 p.m.

Details

Message ID 201002022240.o12Me1iY018842@imap1.linux-foundation.org
State Not Applicable
Headers show

Commit Message

Andrew Morton Feb. 2, 2010, 10:40 p.m.
From: Roel Kluin <roel.kluin@gmail.com>

count is unsigned and cannot be less than 0.

Signed-off-by: Roel Kluin <roel.kluin@gmail.com>
Acked-by: Cyrill Gorcunov <gorcunov@gmail.com>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Cc: Kumar Gala <galak@gate.crashing.org>
Cc: Brian Waite <waite@skycomputers.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
---

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

Comments

Benjamin Herrenschmidt Feb. 3, 2010, 11:21 p.m.
On Tue, 2010-02-02 at 14:40 -0800, akpm@linux-foundation.org wrote:
> From: Roel Kluin <roel.kluin@gmail.com>
> 
> count is unsigned and cannot be less than 0.
> 
> Signed-off-by: Roel Kluin <roel.kluin@gmail.com>
> Acked-by: Cyrill Gorcunov <gorcunov@gmail.com>
> Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
> Cc: Kumar Gala <galak@gate.crashing.org>
> Cc: Brian Waite <waite@skycomputers.com>
> 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.

>  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;
>  
> _
support Feb. 4, 2010, 12:10 a.m.
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: <linuxppc-dev@ozlabs.org>; <roel.kluin@gmail.com>; 
<galak@gate.crashing.org>; <gorcunov@gmail.com>; <waite@skycomputers.com>
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:
>> From: Roel Kluin <roel.kluin@gmail.com>
>>
>> count is unsigned and cannot be less than 0.
>>
>> Signed-off-by: Roel Kluin <roel.kluin@gmail.com>
>> Acked-by: Cyrill Gorcunov <gorcunov@gmail.com>
>> Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
>> Cc: Kumar Gala <galak@gate.crashing.org>
>> Cc: Brian Waite <waite@skycomputers.com>
>> 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.
>
>>  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;
>>
>> _
>
>
>
Benjamin Herrenschmidt Feb. 4, 2010, 12:18 a.m.
On Wed, 2010-02-03 at 19:10 -0500, support wrote:
> 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.

Well, there seem to be some code in the Linux kernel related to that CPU
that is either dead or incomplete. So if you guys have no interest in
it, we might just rip it out completely.

Cheers,
Ben.
support Feb. 4, 2010, 1:47 a.m.
I doubt we'll be going to be using 7448's any more for future product lines.

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: "support" <support@skycomputers.com>
Cc: <akpm@linux-foundation.org>; <linuxppc-dev@ozlabs.org>; 
<roel.kluin@gmail.com>; <galak@gate.crashing.org>; <gorcunov@gmail.com>; 
<waite@skycomputers.com>
Sent: Wednesday, February 03, 2010 7:18 PM
Subject: Re: [patch 1/2] powerpc: Sky CPU: redundant or incorrect tests on 
unsigned


> On Wed, 2010-02-03 at 19:10 -0500, support wrote:
>> 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.
>
> Well, there seem to be some code in the Linux kernel related to that CPU
> that is either dead or incomplete. So if you guys have no interest in
> it, we might just rip it out completely.
>
> Cheers,
> Ben.
>
>
>
Benjamin Herrenschmidt Feb. 4, 2010, 2:01 a.m.
On Wed, 2010-02-03 at 20:47 -0500, support wrote:
> I doubt we'll be going to be using 7448's any more for future product lines.

Hi !

Well, that isn't really the question :-) Is there any interest in
ensuring that your current Sky is supported by upstream linux kernels or
not ? As I said, the current kernel seems to contain code relative to
the Sky CPU that is never enabled and potentially has issue. Are you
guys interested in fixing this so that upstream linux supports your
existing products, or should we just rip the code out ?

Cheers,
Ben.
 
> 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: "support" <support@skycomputers.com>
> Cc: <akpm@linux-foundation.org>; <linuxppc-dev@ozlabs.org>; 
> <roel.kluin@gmail.com>; <galak@gate.crashing.org>; <gorcunov@gmail.com>; 
> <waite@skycomputers.com>
> Sent: Wednesday, February 03, 2010 7:18 PM
> Subject: Re: [patch 1/2] powerpc: Sky CPU: redundant or incorrect tests on 
> unsigned
> 
> 
> > On Wed, 2010-02-03 at 19:10 -0500, support wrote:
> >> 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.
> >
> > Well, there seem to be some code in the Linux kernel related to that CPU
> > that is either dead or incomplete. So if you guys have no interest in
> > it, we might just rip it out completely.
> >
> > Cheers,
> > Ben.
> >
> >
> >
support Feb. 4, 2010, 12:38 p.m.
We don't plan on carrying it forward, so I assume that ripping it out will
not affect us.
Anything new would be completely new development.



-----Original Message-----
From: Benjamin Herrenschmidt [mailto:benh@kernel.crashing.org] 
Sent: Wednesday, February 03, 2010 9:01 PM
To: support
Cc: akpm@linux-foundation.org; linuxppc-dev@ozlabs.org;
roel.kluin@gmail.com; galak@gate.crashing.org; gorcunov@gmail.com;
waite@skycomputers.com
Subject: Re: [patch 1/2] powerpc: Sky CPU: redundant or incorrect tests on
unsigned

On Wed, 2010-02-03 at 20:47 -0500, support wrote:
> I doubt we'll be going to be using 7448's any more for future product
lines.

Hi !

Well, that isn't really the question :-) Is there any interest in
ensuring that your current Sky is supported by upstream linux kernels or
not ? As I said, the current kernel seems to contain code relative to
the Sky CPU that is never enabled and potentially has issue. Are you
guys interested in fixing this so that upstream linux supports your
existing products, or should we just rip the code out ?

Cheers,
Ben.
 
> 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: "support" <support@skycomputers.com>
> Cc: <akpm@linux-foundation.org>; <linuxppc-dev@ozlabs.org>; 
> <roel.kluin@gmail.com>; <galak@gate.crashing.org>; <gorcunov@gmail.com>; 
> <waite@skycomputers.com>
> Sent: Wednesday, February 03, 2010 7:18 PM
> Subject: Re: [patch 1/2] powerpc: Sky CPU: redundant or incorrect tests on

> unsigned
> 
> 
> > On Wed, 2010-02-03 at 19:10 -0500, support wrote:
> >> 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.
> >
> > Well, there seem to be some code in the Linux kernel related to that CPU
> > that is either dead or incomplete. So if you guys have no interest in
> > it, we might just rip it out completely.
> >
> > Cheers,
> > Ben.
> >
> >
> >

Patch hide | download patch | download mbox

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;