Debian Bug report logs - #595805
RFP: devmem2 -- Simple program to read/write from/to any hardware address

Package: wnpp; Maintainer for wnpp is wnpp@debian.org;

Reported by: Michael Opdenacker <michael.opdenacker@free-electrons.com>

Date: Mon, 6 Sep 2010 19:39:05 UTC

Severity: wishlist

Reply or subscribe to this bug.

Toggle useless messages

View this report as an mbox folder, status mbox, maintainer mbox


Report forwarded to debian-bugs-dist@lists.debian.org, michael.opdenacker@free-electrons.com, debian-devel@lists.debian.org, wnpp@debian.org:
Bug#595805; Package wnpp. (Mon, 06 Sep 2010 19:39:08 GMT) Full text and rfc822 format available.

Acknowledgement sent to Michael Opdenacker <michael.opdenacker@free-electrons.com>:
New Bug report received and forwarded. Copy sent to michael.opdenacker@free-electrons.com, debian-devel@lists.debian.org, wnpp@debian.org. (Mon, 06 Sep 2010 19:39:08 GMT) Full text and rfc822 format available.

Message #5 received at submit@bugs.debian.org (full text, mbox):

From: Michael Opdenacker <michael.opdenacker@free-electrons.com>
To: Debian Bug Tracking System <submit@bugs.debian.org>
Subject: ITP: devmem2 -- Simple program to read/write from/to any hardware address
Date: Mon, 06 Sep 2010 21:37:33 +0200
Package: wnpp
Severity: wishlist
Owner: Michael Opdenacker <michael.opdenacker@free-electrons.com>


* Package name    : devmem2
  Version         : 1.0.0
  Upstream Author : Jan-Derk Bakker <jdb@lartmaker.nl>
* URL             : http://www.lartmaker.nl/lartware/port/devmem2.c 
* License         : GPLv2 or later
  Programming Lang: C
  Description     : Simple program to read/write from/to any hardware address

devmem2 can be used to access physical addresses 
in your system, when allowed by the kernel.
It releaves you from having to access
/dev/mem by yourself with a C program, and
allows for quick experiments with the hardware
from the command line, before implementing a
real device driver.




Information forwarded to debian-bugs-dist@lists.debian.org, wnpp@debian.org, Michael Opdenacker <michael.opdenacker@free-electrons.com>:
Bug#595805; Package wnpp. (Mon, 06 Sep 2010 21:09:08 GMT) Full text and rfc822 format available.

Acknowledgement sent to "brian m. carlson" <sandals@crustytoothpaste.net>:
Extra info received and forwarded to list. Copy sent to wnpp@debian.org, Michael Opdenacker <michael.opdenacker@free-electrons.com>. (Mon, 06 Sep 2010 21:09:08 GMT) Full text and rfc822 format available.

Message #10 received at 595805@bugs.debian.org (full text, mbox):

From: "brian m. carlson" <sandals@crustytoothpaste.net>
To: Michael Opdenacker <michael.opdenacker@free-electrons.com>, 595805@bugs.debian.org, debian-devel@lists.debian.org
Subject: Re: Bug#595805: ITP: devmem2 -- Simple program to read/write from/to any hardware address
Date: Mon, 6 Sep 2010 21:03:59 +0000
[Message part 1 (text/plain, inline)]
On Mon, Sep 06, 2010 at 09:37:33PM +0200, Michael Opdenacker wrote:
> Package: wnpp
> Severity: wishlist
> Owner: Michael Opdenacker <michael.opdenacker@free-electrons.com>
> 
> 
> * Package name    : devmem2
>   Version         : 1.0.0
>   Upstream Author : Jan-Derk Bakker <jdb@lartmaker.nl>
> * URL             : http://www.lartmaker.nl/lartware/port/devmem2.c 
> * License         : GPLv2 or later
>   Programming Lang: C
>   Description     : Simple program to read/write from/to any hardware address
> 
> devmem2 can be used to access physical addresses 
> in your system, when allowed by the kernel.
> It releaves you from having to access
> /dev/mem by yourself with a C program, and
> allows for quick experiments with the hardware
> from the command line, before implementing a
> real device driver.

This is simply a really small wrapper around /dev/mem.  Whether it is a
worthwhile enough tool to maintain as a package, I have no opinion.  But
I would like to point out that it is not portable.  It assumes a 4k page
size and that sizeof(unsigned long) == 4.  We have numerous
architectures on which one or both of those are not true.  That doesn't
even take into consideration that poking around in /dev/mem is almost
always the wrong thing.

-- 
brian m. carlson / brian with sandals: Houston, Texas, US
+1 832 623 2791 | http://www.crustytoothpaste.net/~bmc | My opinion only
OpenPGP: RSA v4 4096b: 88AC E9B2 9196 305B A994 7552 F1BA 225C 0223 B187
[signature.asc (application/pgp-signature, inline)]

Information forwarded to debian-bugs-dist@lists.debian.org, wnpp@debian.org, Michael Opdenacker <michael.opdenacker@free-electrons.com>:
Bug#595805; Package wnpp. (Mon, 06 Sep 2010 21:54:02 GMT) Full text and rfc822 format available.

Acknowledgement sent to "brian m. carlson" <sandals@crustytoothpaste.net>:
Extra info received and forwarded to list. Copy sent to wnpp@debian.org, Michael Opdenacker <michael.opdenacker@free-electrons.com>. (Mon, 06 Sep 2010 21:54:03 GMT) Full text and rfc822 format available.

Message #15 received at 595805@bugs.debian.org (full text, mbox):

From: "brian m. carlson" <sandals@crustytoothpaste.net>
To: 595805@bugs.debian.org
Subject: Other problems with devmem2
Date: Mon, 6 Sep 2010 21:51:32 +0000
[Message part 1 (text/plain, inline)]
devmem2 also crashes with a SIGBUS when it's requested to access
unaligned memory on machines that forbid it.  For example, on sparc:

  blackhole ok % sudo ./devmem 0x70000000 w
  /dev/mem opened.
  Memory mapped at address 0xf7fec000.
  Value at address 0x70000000 (0xf7fec000): 0x82106120
  blackhole ok % sudo ./devmem 0x70000001 w
  /dev/mem opened.
  Memory mapped at address 0xf7fc0000.
  zsh: bus error  sudo ./devmem 0x70000001 w

This should not be allowed to occur.  devmem2 should either forbid
unaligned access where the processor forbids it (and that means on
alpha, ia64, and other architectures where PR_SET_UNALIGN is
implemented, unless it's disabled) or perform a fix-up like the kernel
does in such situations.

-- 
brian m. carlson / brian with sandals: Houston, Texas, US
+1 832 623 2791 | http://www.crustytoothpaste.net/~bmc | My opinion only
OpenPGP: RSA v4 4096b: 88AC E9B2 9196 305B A994 7552 F1BA 225C 0223 B187
[signature.asc (application/pgp-signature, inline)]

Information forwarded to debian-bugs-dist@lists.debian.org, wnpp@debian.org, Michael Opdenacker <michael.opdenacker@free-electrons.com>:
Bug#595805; Package wnpp. (Mon, 06 Sep 2010 22:57:03 GMT) Full text and rfc822 format available.

Acknowledgement sent to Ben Hutchings <ben@decadent.org.uk>:
Extra info received and forwarded to list. Copy sent to wnpp@debian.org, Michael Opdenacker <michael.opdenacker@free-electrons.com>. (Mon, 06 Sep 2010 22:57:03 GMT) Full text and rfc822 format available.

Message #20 received at 595805@bugs.debian.org (full text, mbox):

From: Ben Hutchings <ben@decadent.org.uk>
To: Michael Opdenacker <michael.opdenacker@free-electrons.com>, 595805@bugs.debian.org
Subject: Re: Bug#595805: ITP: devmem2 -- Simple program to read/write from/to any hardware address
Date: Mon, 06 Sep 2010 23:54:44 +0100
[Message part 1 (text/plain, inline)]
On Mon, 2010-09-06 at 21:37 +0200, Michael Opdenacker wrote:
> Package: wnpp
> Severity: wishlist
> Owner: Michael Opdenacker <michael.opdenacker@free-electrons.com>
> 
> 
> * Package name    : devmem2
>   Version         : 1.0.0
>   Upstream Author : Jan-Derk Bakker <jdb@lartmaker.nl>
> * URL             : http://www.lartmaker.nl/lartware/port/devmem2.c 
> * License         : GPLv2 or later
>   Programming Lang: C
>   Description     : Simple program to read/write from/to any hardware address
> 
> devmem2 can be used to access physical addresses 
> in your system, when allowed by the kernel.
> It releaves you from having to access
> /dev/mem by yourself with a C program, and
> allows for quick experiments with the hardware
> from the command line, before implementing a
> real device driver.

This is a quick hack, too trivial to deserve a package.  A more useful
tool would be one that allows you to define named registers and fields
in the various spaces they may exist (memory, I/O, PCI config space,
indirect...).  I've written and used something like that in my day job -
though it wasn't general enough to attempt to release.

Ben.

-- 
Ben Hutchings
Once a job is fouled up, anything done to improve it makes it worse.
[signature.asc (application/pgp-signature, inline)]

Information forwarded to debian-bugs-dist@lists.debian.org, wnpp@debian.org:
Bug#595805; Package wnpp. (Tue, 07 Sep 2010 04:57:03 GMT) Full text and rfc822 format available.

Acknowledgement sent to Michael Opdenacker <michael.opdenacker@free-electrons.com>:
Extra info received and forwarded to list. Copy sent to wnpp@debian.org. (Tue, 07 Sep 2010 04:57:03 GMT) Full text and rfc822 format available.

Message #25 received at 595805@bugs.debian.org (full text, mbox):

From: Michael Opdenacker <michael.opdenacker@free-electrons.com>
To: Ben Hutchings <ben@decadent.org.uk>
Cc: 595805@bugs.debian.org
Subject: Re: Bug#595805: ITP: devmem2 -- Simple program to read/write from/to any hardware address
Date: Tue, 07 Sep 2010 06:48:01 +0200
Dear all,

On 09/07/2010 12:54 AM, Ben Hutchings wrote:
> On Mon, 2010-09-06 at 21:37 +0200, Michael Opdenacker wrote:
>   
>> Package: wnpp
>> Severity: wishlist
>> Owner: Michael Opdenacker <michael.opdenacker@free-electrons.com>
>>
>>
>> * Package name    : devmem2
>>   Version         : 1.0.0
>>   Upstream Author : Jan-Derk Bakker <jdb@lartmaker.nl>
>> * URL             : http://www.lartmaker.nl/lartware/port/devmem2.c 
>> * License         : GPLv2 or later
>>   Programming Lang: C
>>   Description     : Simple program to read/write from/to any hardware address
>>
>> devmem2 can be used to access physical addresses 
>> in your system, when allowed by the kernel.
>> It releaves you from having to access
>> /dev/mem by yourself with a C program, and
>> allows for quick experiments with the hardware
>> from the command line, before implementing a
>> real device driver.
>>     
> This is a quick hack, too trivial to deserve a package.  A more useful
> tool would be one that allows you to define named registers and fields
> in the various spaces they may exist (memory, I/O, PCI config space,
> indirect...).  I've written and used something like that in my day job -
> though it wasn't general enough to attempt to release.
>   
Thank you very much for your feedback about devmem2. It's true that it's
a very quick hack, and I now understand that it's not generic and
portable enough to be package in Debian.

However, I do believe something providing this kind of functionality
will be useful. That's all the more true as Debian GNU/Linux is
increasingly used on embedded platforms, and that's the reason why
BusyBox has its own devmem applet (see
http://free-electrons.com/issues/debian/wnpp/595805/devmem.c)

What would you advise me to do next? May I reuse the BusyBox code (which
is an improved version of the original, and probably deserves more to be
included) and propose a package again? Or should we extend the
configuration of the BusyBox package to support the devmem applet (if
needed), and tell users to run "busybox devmem" to get this functionality?

The second choice would be the easiest solution, though less user friendly.

Thanks again,

Cheers,

Michael.

-- 
Michael Opdenacker, Free Electrons
Kernel, drivers, real-time and embedded Linux
development, consulting, training and support.
http://free-electrons.com
+ 33 621 604 642





Information forwarded to debian-bugs-dist@lists.debian.org, wnpp@debian.org, Michael Opdenacker <michael.opdenacker@free-electrons.com>:
Bug#595805; Package wnpp. (Wed, 27 Jul 2011 16:33:15 GMT) Full text and rfc822 format available.

Acknowledgement sent to Lucas Nussbaum <lucas@debian.org>:
Extra info received and forwarded to list. Copy sent to wnpp@debian.org, Michael Opdenacker <michael.opdenacker@free-electrons.com>. (Wed, 27 Jul 2011 16:33:15 GMT) Full text and rfc822 format available.

Message #30 received at 595805@bugs.debian.org (full text, mbox):

From: Lucas Nussbaum <lucas@debian.org>
To: 595805@bugs.debian.org
Cc: control@bugs.debian.org
Subject: devmem2: changing back from ITP to RFP
Date: Wed, 27 Jul 2011 18:02:33 +0200
retitle 595805 RFP: devmem2 -- Simple program to read/write from/to any hardware address
noowner 595805
thanks

Hi,

This is an automatic email to change the status of devmem2 back from ITP
(Intent to Package) to RFP (Request for Package), because this bug hasn't seen
any activity during the last 6 months.

If you are still interested in adopting devmem2, please send a mail to
<control@bugs.debian.org> with:

 retitle 595805 ITP: devmem2 -- Simple program to read/write from/to any hardware address
 owner 595805 !
 thanks

However, it is not recommended to keep ITP for a long time without acting on
the package, as it might cause other prospective maintainers to refrain from
packaging that software. It is also a good idea to document your progress on
this ITP from time to time, by mailing <595805@bugs.debian.org>.

Thank you for your interest in Debian,
-- 
Lucas, for the QA team <debian-qa@lists.debian.org>




Changed Bug title to 'RFP: devmem2 -- Simple program to read/write from/to any hardware address' from 'ITP: devmem2 -- Simple program to read/write from/to any hardware address' Request was from Lucas Nussbaum <lucas@debian.org> to control@bugs.debian.org. (Wed, 27 Jul 2011 16:43:30 GMT) Full text and rfc822 format available.

Removed annotation that Bug was owned by Michael Opdenacker <michael.opdenacker@free-electrons.com>. Request was from Lucas Nussbaum <lucas@debian.org> to control@bugs.debian.org. (Wed, 27 Jul 2011 16:43:31 GMT) Full text and rfc822 format available.

Send a report that this bug log contains spam.


Debian bug tracking system administrator <owner@bugs.debian.org>. Last modified: Sat Apr 19 13:05:15 2014; Machine Name: beach.debian.org

Debian Bug tracking system
Copyright (C) 1999 Darren O. Benham, 1997,2003 nCipher Corporation Ltd, 1994-97 Ian Jackson.