All of lore.kernel.org
 help / color / mirror / Atom feed
* Kernel Debugging Support
@ 2014-08-02  4:47 Nick Krause
  2014-08-02 13:48 ` Alan Stern
  2014-08-04 16:46 ` Sarah Sharp
  0 siblings, 2 replies; 20+ messages in thread
From: Nick Krause @ 2014-08-02  4:47 UTC (permalink / raw)
  To: sarah.a.sharp; +Cc: linux-kernel, linux-usb

Hey Sharp,
After reading around seems people want support for usb debugging in
kgdb or other usb based solutions.
If you and the other developers are able to help me out a bit as I am
new I can definitively write this
area of kgdb support.
Regards Nick
P.S. If  you want Sharp I can change the commit message on my other
commit you didn't like if me or you
talk to Greg in order to remove in from mainline, if no that's OK too.

^ permalink raw reply	[flat|nested] 20+ messages in thread

* Re: Kernel Debugging Support
  2014-08-02  4:47 Kernel Debugging Support Nick Krause
@ 2014-08-02 13:48 ` Alan Stern
  2014-08-03  1:40   ` Nick Krause
  2014-08-04 11:37   ` Austin S Hemmelgarn
  2014-08-04 16:46 ` Sarah Sharp
  1 sibling, 2 replies; 20+ messages in thread
From: Alan Stern @ 2014-08-02 13:48 UTC (permalink / raw)
  To: Nick Krause; +Cc: linux-kernel, USB list

On Sat, 2 Aug 2014, Nick Krause wrote:

> Hey Sharp,
> After reading around seems people want support for usb debugging in
> kgdb or other usb based solutions.
> If you and the other developers are able to help me out a bit as I am
> new I can definitively write this
> area of kgdb support.

Doesn't kgdb already support USB for debugging?

Alan Stern


^ permalink raw reply	[flat|nested] 20+ messages in thread

* Re: Kernel Debugging Support
  2014-08-02 13:48 ` Alan Stern
@ 2014-08-03  1:40   ` Nick Krause
  2014-08-04 11:37   ` Austin S Hemmelgarn
  1 sibling, 0 replies; 20+ messages in thread
From: Nick Krause @ 2014-08-03  1:40 UTC (permalink / raw)
  To: Alan Stern; +Cc: linux-kernel, USB list

On Sat, Aug 2, 2014 at 9:48 AM, Alan Stern <stern@rowland.harvard.edu> wrote:
> On Sat, 2 Aug 2014, Nick Krause wrote:
>
>> Hey Sharp,
>> After reading around seems people want support for usb debugging in
>> kgdb or other usb based solutions.
>> If you and the other developers are able to help me out a bit as I am
>> new I can definitively write this
>> area of kgdb support.
>
> Doesn't kgdb already support USB for debugging?
>
> Alan Stern
>
I am not sure, I can check  the documentation in the kernel first to see,
but from my understanding it seems not.
Regards Nick

^ permalink raw reply	[flat|nested] 20+ messages in thread

* Re: Kernel Debugging Support
  2014-08-02 13:48 ` Alan Stern
  2014-08-03  1:40   ` Nick Krause
@ 2014-08-04 11:37   ` Austin S Hemmelgarn
  2014-08-04 14:21     ` Alan Stern
  1 sibling, 1 reply; 20+ messages in thread
From: Austin S Hemmelgarn @ 2014-08-04 11:37 UTC (permalink / raw)
  To: Alan Stern, Nick Krause; +Cc: linux-kernel, USB list

[-- Attachment #1: Type: text/plain, Size: 1069 bytes --]

On 2014-08-02 09:48, Alan Stern wrote:
> On Sat, 2 Aug 2014, Nick Krause wrote:
> 
>> Hey Sharp,
>> After reading around seems people want support for usb debugging in
>> kgdb or other usb based solutions.
>> If you and the other developers are able to help me out a bit as I am
>> new I can definitively write this
>> area of kgdb support.
> 
> Doesn't kgdb already support USB for debugging?
> 
> Alan Stern

AFAICT, on x86 it only supports using either a console capable serial
port (so you could do that over USB if you have USB serial console
support built-in, but most people I know don't compile that in, and in
fact that is the only reason that i compile USB serial support in
instead of making it a module), and an AT compatible keyboard with any
console option.  It would be really nice to have USB keyboard support in
there so that you don't have to reboot with special options and extra
hardware plugged in to get to the debugger, although doing something
that supports more than just the HID boot protocol will probably be tricky.


[-- Attachment #2: S/MIME Cryptographic Signature --]
[-- Type: application/pkcs7-signature, Size: 2967 bytes --]

^ permalink raw reply	[flat|nested] 20+ messages in thread

* Re: Kernel Debugging Support
  2014-08-04 11:37   ` Austin S Hemmelgarn
@ 2014-08-04 14:21     ` Alan Stern
  2014-08-04 14:29       ` Austin S Hemmelgarn
  0 siblings, 1 reply; 20+ messages in thread
From: Alan Stern @ 2014-08-04 14:21 UTC (permalink / raw)
  To: Austin S Hemmelgarn; +Cc: Nick Krause, linux-kernel, USB list

On Mon, 4 Aug 2014, Austin S Hemmelgarn wrote:

> On 2014-08-02 09:48, Alan Stern wrote:
> > On Sat, 2 Aug 2014, Nick Krause wrote:
> > 
> >> Hey Sharp,
> >> After reading around seems people want support for usb debugging in
> >> kgdb or other usb based solutions.
> >> If you and the other developers are able to help me out a bit as I am
> >> new I can definitively write this
> >> area of kgdb support.
> > 
> > Doesn't kgdb already support USB for debugging?
> > 
> > Alan Stern
> 
> AFAICT, on x86 it only supports using either a console capable serial
> port (so you could do that over USB if you have USB serial console
> support built-in, but most people I know don't compile that in, and in
> fact that is the only reason that i compile USB serial support in
> instead of making it a module), and an AT compatible keyboard with any
> console option.

What about with a USB debugging device (CONFIG_EARLY_PRINTK_DBGP)?  
That's how debugging over USB is _supposed_ to be done.

>  It would be really nice to have USB keyboard support in
> there so that you don't have to reboot with special options and extra
> hardware plugged in to get to the debugger, although doing something
> that supports more than just the HID boot protocol will probably be tricky.

Is there some reason why kgdb doesn't simply use the kernel's input 
layer?  If there is, that same reason probably prevents it from using 
USB.

Alan Stern


^ permalink raw reply	[flat|nested] 20+ messages in thread

* Re: Kernel Debugging Support
  2014-08-04 14:21     ` Alan Stern
@ 2014-08-04 14:29       ` Austin S Hemmelgarn
  2014-08-04 14:45         ` Richard Weinberger
  0 siblings, 1 reply; 20+ messages in thread
From: Austin S Hemmelgarn @ 2014-08-04 14:29 UTC (permalink / raw)
  To: Alan Stern; +Cc: Nick Krause, linux-kernel, USB list

[-- Attachment #1: Type: text/plain, Size: 1714 bytes --]

On 2014-08-04 10:21, Alan Stern wrote:
> On Mon, 4 Aug 2014, Austin S Hemmelgarn wrote:
> 
>> On 2014-08-02 09:48, Alan Stern wrote:
>>> On Sat, 2 Aug 2014, Nick Krause wrote:
>>>
>>>> Hey Sharp,
>>>> After reading around seems people want support for usb debugging in
>>>> kgdb or other usb based solutions.
>>>> If you and the other developers are able to help me out a bit as I am
>>>> new I can definitively write this
>>>> area of kgdb support.
>>>
>>> Doesn't kgdb already support USB for debugging?
>>>
>>> Alan Stern
>>
>> AFAICT, on x86 it only supports using either a console capable serial
>> port (so you could do that over USB if you have USB serial console
>> support built-in, but most people I know don't compile that in, and in
>> fact that is the only reason that i compile USB serial support in
>> instead of making it a module), and an AT compatible keyboard with any
>> console option.
> 
> What about with a USB debugging device (CONFIG_EARLY_PRINTK_DBGP)?  
> That's how debugging over USB is _supposed_ to be done.
Yes, except those are really expensive, and on some it's pretty easy if
you don't know what you are doing to really screw things up.
> 
>>  It would be really nice to have USB keyboard support in
>> there so that you don't have to reboot with special options and extra
>> hardware plugged in to get to the debugger, although doing something
>> that supports more than just the HID boot protocol will probably be tricky.
> 
> Is there some reason why kgdb doesn't simply use the kernel's input 
> layer?  If there is, that same reason probably prevents it from using 
> USB.
> 
I believe it's to minimize the in-kernel dependencies.



[-- Attachment #2: S/MIME Cryptographic Signature --]
[-- Type: application/pkcs7-signature, Size: 2967 bytes --]

^ permalink raw reply	[flat|nested] 20+ messages in thread

* Re: Kernel Debugging Support
  2014-08-04 14:29       ` Austin S Hemmelgarn
@ 2014-08-04 14:45         ` Richard Weinberger
  0 siblings, 0 replies; 20+ messages in thread
From: Richard Weinberger @ 2014-08-04 14:45 UTC (permalink / raw)
  To: Austin S Hemmelgarn; +Cc: Alan Stern, Nick Krause, linux-kernel, USB list

On Mon, Aug 4, 2014 at 4:29 PM, Austin S Hemmelgarn
<ahferroin7@gmail.com> wrote:
> On 2014-08-04 10:21, Alan Stern wrote:
>> On Mon, 4 Aug 2014, Austin S Hemmelgarn wrote:
>>
>>> On 2014-08-02 09:48, Alan Stern wrote:
>>>> On Sat, 2 Aug 2014, Nick Krause wrote:
>>>>
>>>>> Hey Sharp,
>>>>> After reading around seems people want support for usb debugging in
>>>>> kgdb or other usb based solutions.
>>>>> If you and the other developers are able to help me out a bit as I am
>>>>> new I can definitively write this
>>>>> area of kgdb support.
>>>>
>>>> Doesn't kgdb already support USB for debugging?
>>>>
>>>> Alan Stern
>>>
>>> AFAICT, on x86 it only supports using either a console capable serial
>>> port (so you could do that over USB if you have USB serial console
>>> support built-in, but most people I know don't compile that in, and in
>>> fact that is the only reason that i compile USB serial support in
>>> instead of making it a module), and an AT compatible keyboard with any
>>> console option.
>>
>> What about with a USB debugging device (CONFIG_EARLY_PRINTK_DBGP)?
>> That's how debugging over USB is _supposed_ to be done.
> Yes, except those are really expensive, and on some it's pretty easy if
> you don't know what you are doing to really screw things up.

All you need is a Computer with an UDC. Linux has a debugport gadget.

-- 
Thanks,
//richard

^ permalink raw reply	[flat|nested] 20+ messages in thread

* Re: Kernel Debugging Support
  2014-08-02  4:47 Kernel Debugging Support Nick Krause
  2014-08-02 13:48 ` Alan Stern
@ 2014-08-04 16:46 ` Sarah Sharp
  2014-08-04 19:07   ` Paul Zimmerman
  1 sibling, 1 reply; 20+ messages in thread
From: Sarah Sharp @ 2014-08-04 16:46 UTC (permalink / raw)
  To: Nick Krause; +Cc: linux-kernel, linux-usb, Nyman, Mathias

On Sat, Aug 02, 2014 at 12:47:59AM -0400, Nick Krause wrote:
> Hey Sharp,

Hi Krause,

Please Cc the new xHCI driver maintainer, Mathias Nyman.  I'm officially
retired from USB development and have moved onto other projects. :)

> After reading around seems people want support for usb debugging in
> kgdb or other usb based solutions.

Yes, early boot USB debug over xHCI has been a low-priority feature
request.

Unfortunately, USB debug is an optional feature for xHCI host
controllers, so many of them don't have USB debug ports.  Even if it is
included, the USB debug ports are often either routed to internal USB
ports or not exposed on the board altogether.  Since it's not widely
available, it's not a high priority to implement.

> If you and the other developers are able to help me out a bit as I am
> new I can definitively write this
> area of kgdb support.

The kgdb support is all there.  It's the xHCI host controller driver
debug port support that is needed.

Hmm, I only see one commit from your email address in Greg's tree.  I
think you should work on some smaller clean ups and bug fixes, and get
some more patches into mainline before you go on to tackle a larger
feature like this.  Perhaps Mathias has a smaller task that would be
good for you to tackle?

There's a good tutorial here on how to create a kernel patch, and
respond properly to patch review and rework requests:

http://kernelnewbies.org/OPWfirstpatch

And here's my personal philosophy on how to create a patchset:

http://sarah.thesharps.us/2013/05/08/patchsets-for-dinner/

> Regards Nick
> P.S. If  you want Sharp I can change the commit message on my other
> commit you didn't like if me or you
> talk to Greg in order to remove in from mainline, if no that's OK too.

I don't understand what the above sentence means.  What commit message
are you referencing?  What do you mean by "remove in from mainline"?

Try again?

Sarah Sharp

^ permalink raw reply	[flat|nested] 20+ messages in thread

* RE: Kernel Debugging Support
  2014-08-04 16:46 ` Sarah Sharp
@ 2014-08-04 19:07   ` Paul Zimmerman
  2014-08-04 19:23     ` Valdis.Kletnieks
  0 siblings, 1 reply; 20+ messages in thread
From: Paul Zimmerman @ 2014-08-04 19:07 UTC (permalink / raw)
  To: Sarah Sharp; +Cc: linux-kernel, linux-usb, Nyman, Mathias, Nick Krause

> From: linux-usb-owner@vger.kernel.org [mailto:linux-usb-owner@vger.kernel.org] On Behalf Of Sarah Sharp
> Sent: Monday, August 04, 2014 9:47 AM
> 
> Please Cc the new xHCI driver maintainer, Mathias Nyman.  I'm officially
> retired from USB development and have moved onto other projects. :)
> 
> > After reading around seems people want support for usb debugging in
> > kgdb or other usb based solutions.
> 
> Yes, early boot USB debug over xHCI has been a low-priority feature
> request.
> 
> Unfortunately, USB debug is an optional feature for xHCI host
> controllers, so many of them don't have USB debug ports.  Even if it is
> included, the USB debug ports are often either routed to internal USB
> ports or not exposed on the board altogether.  Since it's not widely
> available, it's not a high priority to implement.

Hi Sarah,

Are you sure about that? Last I heard, xHCI debug support was a logo
requirement from Microsoft for Windows 8 and above, so I would have
thought that most vendors would have implemented it by now. I know
Synopsys put a lot of effort into making sure it works in our IP. Or
did Microsoft relax that requirement at the last minute?

-- 
Paul


^ permalink raw reply	[flat|nested] 20+ messages in thread

* Re: Kernel Debugging Support
  2014-08-04 19:07   ` Paul Zimmerman
@ 2014-08-04 19:23     ` Valdis.Kletnieks
  2014-08-04 19:40       ` Paul Zimmerman
  0 siblings, 1 reply; 20+ messages in thread
From: Valdis.Kletnieks @ 2014-08-04 19:23 UTC (permalink / raw)
  To: Paul Zimmerman
  Cc: Sarah Sharp, linux-kernel, linux-usb, Nyman, Mathias, Nick Krause

[-- Attachment #1: Type: text/plain, Size: 1947 bytes --]

On Mon, 04 Aug 2014 19:07:53 -0000, Paul Zimmerman said:

> Are you sure about that? Last I heard, xHCI debug support was a logo
> requirement from Microsoft for Windows 8 and above, so I would have
> thought that most vendors would have implemented it by now.

There's a lot of gear out in the real world that was manufactured before
Windows 8 was released.

And the actual requirement, as listed at:

http://msdn.microsoft.com/en-us/library/windows/hardware/jj128256

doesn't actually require USB debug -it requires a debug port, and xHCI
is below ethernet on the preference list.  As it says:

---
The next version of Windows will support several different debug transports.
They are listed below in the preferred order of implementation.

Hardware Debugging Transports

Ethernet Network Interface Card from the supported list: http://msdn.microsoft.com/en-us/library/windows/hardware/hh830880

USB 3.0 - xHCI controller compliant to xHCI debug specification.

1394 OHCI compliant Firewire controllers.

USB2 OTG (on supported hardware for Windows, recommend XHCI debug instead).

USB 2.0 EHCI debug (the debug enabled port must be user accessible). Legacy Serial (16550 compatible programming interface).

 ADDITIONAL REQUIREMENTSFOR ALL OF THE ABOVE IMPLEMENTATIONS THE FOLLOWING MUST APPLY:

There must be at least one user accessible debug port on the machine. It is
acceptable on systems which choose to not expose a USB port or any other
acceptable port from the list above to instead require a separate debugging
board or device that provides the ability to debug via one (or more) of the
transports above. That device/board must terminate in the same standard port as
would be used for the transport if it were \u2018onboard\u2019 the machine. If
this device is required it must be documented in the system specifications, be
user serviceable, be user installable on the machine, and available for sale
from the machine\u2019s vendor.


[-- Attachment #2: Type: application/pgp-signature, Size: 848 bytes --]

^ permalink raw reply	[flat|nested] 20+ messages in thread

* RE: Kernel Debugging Support
  2014-08-04 19:23     ` Valdis.Kletnieks
@ 2014-08-04 19:40       ` Paul Zimmerman
  2014-08-04 20:27         ` Valdis.Kletnieks
  0 siblings, 1 reply; 20+ messages in thread
From: Paul Zimmerman @ 2014-08-04 19:40 UTC (permalink / raw)
  To: Valdis.Kletnieks
  Cc: Sarah Sharp, linux-kernel, linux-usb, Nyman, Mathias, Nick Krause

> From: Valdis.Kletnieks@vt.edu [mailto:Valdis.Kletnieks@vt.edu]
> Sent: Monday, August 04, 2014 12:23 PM
> 
> On Mon, 04 Aug 2014 19:07:53 -0000, Paul Zimmerman said:
> 
> > Are you sure about that? Last I heard, xHCI debug support was a logo
> > requirement from Microsoft for Windows 8 and above, so I would have
> > thought that most vendors would have implemented it by now.
> 
> There's a lot of gear out in the real world that was manufactured before
> Windows 8 was released.
> 
> And the actual requirement, as listed at:
> 
> http://msdn.microsoft.com/en-us/library/windows/hardware/jj128256
> 
> doesn't actually require USB debug -it requires a debug port, and xHCI
> is below ethernet on the preference list.  As it says:
> 
> ---
> The next version of Windows will support several different debug transports.
> They are listed below in the preferred order of implementation.
> 
> Hardware Debugging Transports
> 
> Ethernet Network Interface Card from the supported list: http://msdn.microsoft.com/en-
> us/library/windows/hardware/hh830880
> 
> USB 3.0 - xHCI controller compliant to xHCI debug specification.
> 
> 1394 OHCI compliant Firewire controllers.
> 
> USB2 OTG (on supported hardware for Windows, recommend XHCI debug instead).
> 
> USB 2.0 EHCI debug (the debug enabled port must be user accessible). Legacy Serial (16550 compatible
> programming interface).

Ah, you didn't read far enough down the page :)

---
System.Fundamentals.DebugPort.USB.SystemExposesDebugInterfaceUsb
USB 3 system exposes debug interface that complies with Debug Port Specification
 
Target Feature
 System.Fundamentals.DebugPort.USB
 
Applies to
 Windows 8 Client x86, x64, ARM (Windows RT)
 Windows 8.1 Client x86, x64, ARM (Windows RT 8.1)
 Windows Server 2012 R2 x64
 Windows Server 2012 x64

Description

Systems that support USB 3 are required to have xHCI controller(s) compliant to the xHCI debug specification. The xHCI controller(s) shall be memory mapped.

There must be at least one user accessible USB 3.0 debug port on the machine.

...

Enforcement Date
 Mar. 01, 2012
---

So I have to believe there are a *lot* of systems out there that do support xHCI debug.

-- 
Paul


^ permalink raw reply	[flat|nested] 20+ messages in thread

* Re: Kernel Debugging Support
  2014-08-04 19:40       ` Paul Zimmerman
@ 2014-08-04 20:27         ` Valdis.Kletnieks
  2014-08-04 21:55           ` Paul Zimmerman
  0 siblings, 1 reply; 20+ messages in thread
From: Valdis.Kletnieks @ 2014-08-04 20:27 UTC (permalink / raw)
  To: Paul Zimmerman
  Cc: Sarah Sharp, linux-kernel, linux-usb, Nyman, Mathias, Nick Krause

[-- Attachment #1: Type: text/plain, Size: 519 bytes --]

On Mon, 04 Aug 2014 19:40:15 -0000, Paul Zimmerman said:

> Ah, you didn't read far enough down the page :)

I'm willing to bet a large pizza with everything but anchovies that
out in the real world, a lot of implementors didn't read further either. :)

> So I have to believe there are a *lot* of systems out there that do support xHCI debug.

Possibly. But enough to make an actual critical mass to motivate somebody
to write code? Or do you get more bang-for-buck by fixing kgdb to support
debugging over Ethernet?


[-- Attachment #2: Type: application/pgp-signature, Size: 848 bytes --]

^ permalink raw reply	[flat|nested] 20+ messages in thread

* RE: Kernel Debugging Support
  2014-08-04 20:27         ` Valdis.Kletnieks
@ 2014-08-04 21:55           ` Paul Zimmerman
  2014-08-04 22:49             ` Nick Krause
  0 siblings, 1 reply; 20+ messages in thread
From: Paul Zimmerman @ 2014-08-04 21:55 UTC (permalink / raw)
  To: Valdis.Kletnieks, Nick Krause
  Cc: Sarah Sharp, linux-kernel, linux-usb, Nyman, Mathias

> From: Valdis.Kletnieks@vt.edu [mailto:Valdis.Kletnieks@vt.edu]
> Sent: Monday, August 04, 2014 1:28 PM
> 
> On Mon, 04 Aug 2014 19:40:15 -0000, Paul Zimmerman said:
> 
> > Ah, you didn't read far enough down the page :)
> 
> I'm willing to bet a large pizza with everything but anchovies that
> out in the real world, a lot of implementors didn't read further either. :)

Nah, I won't take that bet :)

> > So I have to believe there are a *lot* of systems out there that do support xHCI debug.
> 
> Possibly. But enough to make an actual critical mass to motivate somebody
> to write code? Or do you get more bang-for-buck by fixing kgdb to support
> debugging over Ethernet?

Well, code to support the xHCI debug capability has been written, see
http://marc.info/?l=linux-usb&m=135948845511047. But I did not get
approval from my management to spend the time needed to integrate this
into the kernel's kgdb support.

Nick, if you are still interested in this, you could take a look at the
above code, and see if you can work out how to modify it to make it work
with kgdb. But you will need a PC that has a debug-capable xHCI
controller in order to test it. If you have PC or laptop with USB 3.0
built-in that has the Windows 8 logo, I think there's a good chance you
already have one. Or, according to
http://pete.akeo.ie/2011/08/do-necrenesas-upd720200-based-usb-30.html, 
plug-in USB 3.0 host cards that use the newer Renesas uPD720201 chipset
also have the debug capability.

Note that the above patch is against a pretty old kernel (3.6), so the
first thing you would need to do is forward-port it to work on the
latest kernel. As a plus, that would give you some real experience
working with kernel code, which everyone seems to agree you need ;)

-- 
Paul


^ permalink raw reply	[flat|nested] 20+ messages in thread

* Re: Kernel Debugging Support
  2014-08-04 21:55           ` Paul Zimmerman
@ 2014-08-04 22:49             ` Nick Krause
  2014-08-04 23:03               ` Paul Zimmerman
  0 siblings, 1 reply; 20+ messages in thread
From: Nick Krause @ 2014-08-04 22:49 UTC (permalink / raw)
  To: Paul Zimmerman
  Cc: Valdis.Kletnieks, Sarah Sharp, linux-kernel, linux-usb, Nyman, Mathias

On Mon, Aug 4, 2014 at 5:55 PM, Paul Zimmerman
<Paul.Zimmerman@synopsys.com> wrote:
>> From: Valdis.Kletnieks@vt.edu [mailto:Valdis.Kletnieks@vt.edu]
>> Sent: Monday, August 04, 2014 1:28 PM
>>
>> On Mon, 04 Aug 2014 19:40:15 -0000, Paul Zimmerman said:
>>
>> > Ah, you didn't read far enough down the page :)
>>
>> I'm willing to bet a large pizza with everything but anchovies that
>> out in the real world, a lot of implementors didn't read further either. :)
>
> Nah, I won't take that bet :)
>
>> > So I have to believe there are a *lot* of systems out there that do support xHCI debug.
>>
>> Possibly. But enough to make an actual critical mass to motivate somebody
>> to write code? Or do you get more bang-for-buck by fixing kgdb to support
>> debugging over Ethernet?
>
> Well, code to support the xHCI debug capability has been written, see
> http://marc.info/?l=linux-usb&m=135948845511047. But I did not get
> approval from my management to spend the time needed to integrate this
> into the kernel's kgdb support.
>
> Nick, if you are still interested in this, you could take a look at the
> above code, and see if you can work out how to modify it to make it work
> with kgdb. But you will need a PC that has a debug-capable xHCI
> controller in order to test it. If you have PC or laptop with USB 3.0
> built-in that has the Windows 8 logo, I think there's a good chance you
> already have one. Or, according to
> http://pete.akeo.ie/2011/08/do-necrenesas-upd720200-based-usb-30.html,
> plug-in USB 3.0 host cards that use the newer Renesas uPD720201 chipset
> also have the debug capability.
>
> Note that the above patch is against a pretty old kernel (3.6), so the
> first thing you would need to do is forward-port it to work on the
> latest kernel. As a plus, that would give you some real experience
> working with kernel code, which everyone seems to agree you need ;)
>
> --
> Paul
>

Paul ,
My computer is rather old now as of Sandy Bridge days, so I probably
can't test the patch
on my own machine. However I will look at the code and see if I can
forward port it
against the usb git tree I have a current version of. In addition I
would like the new xhci
maintainers information in  order to send out a patch with the
Maintainer for xhci updated.
Regards Nick

^ permalink raw reply	[flat|nested] 20+ messages in thread

* RE: Kernel Debugging Support
  2014-08-04 22:49             ` Nick Krause
@ 2014-08-04 23:03               ` Paul Zimmerman
  2014-08-04 23:11                 ` Nick Krause
  0 siblings, 1 reply; 20+ messages in thread
From: Paul Zimmerman @ 2014-08-04 23:03 UTC (permalink / raw)
  To: Nick Krause
  Cc: Valdis.Kletnieks, Sarah Sharp, linux-kernel, linux-usb, Nyman, Mathias

[-- Warning: decoded text below may be mangled, UTF-8 assumed --]
[-- Attachment #1: Type: text/plain; charset="utf-8", Size: 2973 bytes --]

> From: Nick Krause [mailto:xerofoify@gmail.com]
> Sent: Monday, August 04, 2014 3:50 PM
> 
> On Mon, Aug 4, 2014 at 5:55 PM, Paul Zimmerman
> <Paul.Zimmerman@synopsys.com> wrote:
> >> From: Valdis.Kletnieks@vt.edu [mailto:Valdis.Kletnieks@vt.edu]
> >> Sent: Monday, August 04, 2014 1:28 PM
> >>
> >> On Mon, 04 Aug 2014 19:40:15 -0000, Paul Zimmerman said:
> >>
> >> > Ah, you didn't read far enough down the page :)
> >>
> >> I'm willing to bet a large pizza with everything but anchovies that
> >> out in the real world, a lot of implementors didn't read further either. :)
> >
> > Nah, I won't take that bet :)
> >
> >> > So I have to believe there are a *lot* of systems out there that do support xHCI debug.
> >>
> >> Possibly. But enough to make an actual critical mass to motivate somebody
> >> to write code? Or do you get more bang-for-buck by fixing kgdb to support
> >> debugging over Ethernet?
> >
> > Well, code to support the xHCI debug capability has been written, see
> > http://marc.info/?l=linux-usb&m=135948845511047. But I did not get
> > approval from my management to spend the time needed to integrate this
> > into the kernel's kgdb support.
> >
> > Nick, if you are still interested in this, you could take a look at the
> > above code, and see if you can work out how to modify it to make it work
> > with kgdb. But you will need a PC that has a debug-capable xHCI
> > controller in order to test it. If you have PC or laptop with USB 3.0
> > built-in that has the Windows 8 logo, I think there's a good chance you
> > already have one. Or, according to
> > http://pete.akeo.ie/2011/08/do-necrenesas-upd720200-based-usb-30.html,
> > plug-in USB 3.0 host cards that use the newer Renesas uPD720201 chipset
> > also have the debug capability.
> >
> > Note that the above patch is against a pretty old kernel (3.6), so the
> > first thing you would need to do is forward-port it to work on the
> > latest kernel. As a plus, that would give you some real experience
> > working with kernel code, which everyone seems to agree you need ;)
> >
> > --
> > Paul
> >
> 
> Paul ,
> My computer is rather old now as of Sandy Bridge days, so I probably
> can't test the patch
> on my own machine. However I will look at the code and see if I can
> forward port it
> against the usb git tree I have a current version of. In addition I
> would like the new xhci
> maintainers information in  order to send out a patch with the
> Maintainer for xhci updated.

Sarah already told you who the new maintainer is, and then CCed him
on this thread. Hint: There is a file name 'MAINTAINERS' in the root
of the kernel tree, which tells you who the maintainers are for all of
the subsystems. Please read Documentation/SubmittingPatches, it has a
lot of information like this that you need to know.

-- 
Paul

ÿôèº{.nÇ+‰·Ÿ®‰­†+%ŠËÿ±éݶ\x17¥Šwÿº{.nÇ+‰·¥Š{±þG«éÿŠ{ayº\x1dʇڙë,j\a­¢f£¢·hšïêÿ‘êçz_è®\x03(­éšŽŠÝ¢j"ú\x1a¶^[m§ÿÿ¾\a«þG«éÿ¢¸?™¨è­Ú&£ø§~á¶iO•æ¬z·švØ^\x14\x04\x1a¶^[m§ÿÿÃ\fÿ¶ìÿ¢¸?–I¥

^ permalink raw reply	[flat|nested] 20+ messages in thread

* Re: Kernel Debugging Support
  2014-08-04 23:03               ` Paul Zimmerman
@ 2014-08-04 23:11                 ` Nick Krause
  2014-08-05  0:12                   ` Sarah Sharp
  0 siblings, 1 reply; 20+ messages in thread
From: Nick Krause @ 2014-08-04 23:11 UTC (permalink / raw)
  To: Paul Zimmerman
  Cc: Valdis.Kletnieks, Sarah Sharp, linux-kernel, linux-usb, Nyman, Mathias

On Mon, Aug 4, 2014 at 7:03 PM, Paul Zimmerman
<Paul.Zimmerman@synopsys.com> wrote:
>> From: Nick Krause [mailto:xerofoify@gmail.com]
>> Sent: Monday, August 04, 2014 3:50 PM
>>
>> On Mon, Aug 4, 2014 at 5:55 PM, Paul Zimmerman
>> <Paul.Zimmerman@synopsys.com> wrote:
>> >> From: Valdis.Kletnieks@vt.edu [mailto:Valdis.Kletnieks@vt.edu]
>> >> Sent: Monday, August 04, 2014 1:28 PM
>> >>
>> >> On Mon, 04 Aug 2014 19:40:15 -0000, Paul Zimmerman said:
>> >>
>> >> > Ah, you didn't read far enough down the page :)
>> >>
>> >> I'm willing to bet a large pizza with everything but anchovies that
>> >> out in the real world, a lot of implementors didn't read further either. :)
>> >
>> > Nah, I won't take that bet :)
>> >
>> >> > So I have to believe there are a *lot* of systems out there that do support xHCI debug.
>> >>
>> >> Possibly. But enough to make an actual critical mass to motivate somebody
>> >> to write code? Or do you get more bang-for-buck by fixing kgdb to support
>> >> debugging over Ethernet?
>> >
>> > Well, code to support the xHCI debug capability has been written, see
>> > http://marc.info/?l=linux-usb&m=135948845511047. But I did not get
>> > approval from my management to spend the time needed to integrate this
>> > into the kernel's kgdb support.
>> >
>> > Nick, if you are still interested in this, you could take a look at the
>> > above code, and see if you can work out how to modify it to make it work
>> > with kgdb. But you will need a PC that has a debug-capable xHCI
>> > controller in order to test it. If you have PC or laptop with USB 3.0
>> > built-in that has the Windows 8 logo, I think there's a good chance you
>> > already have one. Or, according to
>> > http://pete.akeo.ie/2011/08/do-necrenesas-upd720200-based-usb-30.html,
>> > plug-in USB 3.0 host cards that use the newer Renesas uPD720201 chipset
>> > also have the debug capability.
>> >
>> > Note that the above patch is against a pretty old kernel (3.6), so the
>> > first thing you would need to do is forward-port it to work on the
>> > latest kernel. As a plus, that would give you some real experience
>> > working with kernel code, which everyone seems to agree you need ;)
>> >
>> > --
>> > Paul
>> >
>>
>> Paul ,
>> My computer is rather old now as of Sandy Bridge days, so I probably
>> can't test the patch
>> on my own machine. However I will look at the code and see if I can
>> forward port it
>> against the usb git tree I have a current version of. In addition I
>> would like the new xhci
>> maintainers information in  order to send out a patch with the
>> Maintainer for xhci updated.
>
> Sarah already told you who the new maintainer is, and then CCed him
> on this thread. Hint: There is a file name 'MAINTAINERS' in the root
> of the kernel tree, which tells you who the maintainers are for all of
> the subsystems. Please read Documentation/SubmittingPatches, it has a
> lot of information like this that you need to know.
>
> --
> Paul
>
Thanks I will read this file and thanks for the information. I known
where the file is I will
add the information then.
Regards Nick

^ permalink raw reply	[flat|nested] 20+ messages in thread

* Re: Kernel Debugging Support
  2014-08-04 23:11                 ` Nick Krause
@ 2014-08-05  0:12                   ` Sarah Sharp
  2014-08-05  1:33                     ` Nick Krause
  0 siblings, 1 reply; 20+ messages in thread
From: Sarah Sharp @ 2014-08-05  0:12 UTC (permalink / raw)
  To: Nick Krause
  Cc: Paul Zimmerman, Valdis.Kletnieks, linux-kernel, linux-usb, Nyman,
	Mathias

On Mon, Aug 04, 2014 at 07:11:07PM -0400, Nick Krause wrote:
> On Mon, Aug 4, 2014 at 7:03 PM, Paul Zimmerman
> <Paul.Zimmerman@synopsys.com> wrote:
> >> From: Nick Krause [mailto:xerofoify@gmail.com]

[snip]

> >> Paul ,
> >> My computer is rather old now as of Sandy Bridge days, so I probably
> >> can't test the patch
> >> on my own machine. However I will look at the code and see if I can
> >> forward port it
> >> against the usb git tree I have a current version of. In addition I
> >> would like the new xhci
> >> maintainers information in  order to send out a patch with the
> >> Maintainer for xhci updated.
> >
> > Sarah already told you who the new maintainer is, and then CCed him
> > on this thread. Hint: There is a file name 'MAINTAINERS' in the root
> > of the kernel tree, which tells you who the maintainers are for all of
> > the subsystems. Please read Documentation/SubmittingPatches, it has a
> > lot of information like this that you need to know.
> >
> > --
> > Paul
> >
> Thanks I will read this file and thanks for the information. I known
> where the file is I will
> add the information then.

You may be looking at an older version of MAINTAINERS.  Mathias has only
been marked as the maintainer since 3.15.  Which kernel version are you
working on?

Sarah Sharp

^ permalink raw reply	[flat|nested] 20+ messages in thread

* Re: Kernel Debugging Support
  2014-08-05  0:12                   ` Sarah Sharp
@ 2014-08-05  1:33                     ` Nick Krause
  2014-08-05  3:18                       ` Nick Krause
  0 siblings, 1 reply; 20+ messages in thread
From: Nick Krause @ 2014-08-05  1:33 UTC (permalink / raw)
  To: Sarah Sharp
  Cc: Paul Zimmerman, Valdis.Kletnieks, linux-kernel, linux-usb, Nyman,
	Mathias

On Mon, Aug 4, 2014 at 8:12 PM, Sarah Sharp
<sarah.a.sharp@linux.intel.com> wrote:
> On Mon, Aug 04, 2014 at 07:11:07PM -0400, Nick Krause wrote:
>> On Mon, Aug 4, 2014 at 7:03 PM, Paul Zimmerman
>> <Paul.Zimmerman@synopsys.com> wrote:
>> >> From: Nick Krause [mailto:xerofoify@gmail.com]
>
> [snip]
>
>> >> Paul ,
>> >> My computer is rather old now as of Sandy Bridge days, so I probably
>> >> can't test the patch
>> >> on my own machine. However I will look at the code and see if I can
>> >> forward port it
>> >> against the usb git tree I have a current version of. In addition I
>> >> would like the new xhci
>> >> maintainers information in  order to send out a patch with the
>> >> Maintainer for xhci updated.
>> >
>> > Sarah already told you who the new maintainer is, and then CCed him
>> > on this thread. Hint: There is a file name 'MAINTAINERS' in the root
>> > of the kernel tree, which tells you who the maintainers are for all of
>> > the subsystems. Please read Documentation/SubmittingPatches, it has a
>> > lot of information like this that you need to know.
>> >
>> > --
>> > Paul
>> >
>> Thanks I will read this file and thanks for the information. I known
>> where the file is I will
>> add the information then.
>
> You may be looking at an older version of MAINTAINERS.  Mathias has only
> been marked as the maintainer since 3.15.  Which kernel version are you
> working on?
>
> Sarah Sharp

Hey Sarah,
Sorry about that but I am working on the latest tree from linus using
git and I checked seems he is there,
I didn't known it was updated.
Sorry and Thanks Nick

^ permalink raw reply	[flat|nested] 20+ messages in thread

* Re: Kernel Debugging Support
  2014-08-05  1:33                     ` Nick Krause
@ 2014-08-05  3:18                       ` Nick Krause
  2014-08-05  5:32                         ` Nick Krause
  0 siblings, 1 reply; 20+ messages in thread
From: Nick Krause @ 2014-08-05  3:18 UTC (permalink / raw)
  To: Sarah Sharp
  Cc: Paul Zimmerman, Valdis.Kletnieks, linux-kernel, linux-usb, Nyman,
	Mathias

On Mon, Aug 4, 2014 at 9:33 PM, Nick Krause <xerofoify@gmail.com> wrote:
> On Mon, Aug 4, 2014 at 8:12 PM, Sarah Sharp
> <sarah.a.sharp@linux.intel.com> wrote:
>> On Mon, Aug 04, 2014 at 07:11:07PM -0400, Nick Krause wrote:
>>> On Mon, Aug 4, 2014 at 7:03 PM, Paul Zimmerman
>>> <Paul.Zimmerman@synopsys.com> wrote:
>>> >> From: Nick Krause [mailto:xerofoify@gmail.com]
>>
>> [snip]
>>
>>> >> Paul ,
>>> >> My computer is rather old now as of Sandy Bridge days, so I probably
>>> >> can't test the patch
>>> >> on my own machine. However I will look at the code and see if I can
>>> >> forward port it
>>> >> against the usb git tree I have a current version of. In addition I
>>> >> would like the new xhci
>>> >> maintainers information in  order to send out a patch with the
>>> >> Maintainer for xhci updated.
>>> >
>>> > Sarah already told you who the new maintainer is, and then CCed him
>>> > on this thread. Hint: There is a file name 'MAINTAINERS' in the root
>>> > of the kernel tree, which tells you who the maintainers are for all of
>>> > the subsystems. Please read Documentation/SubmittingPatches, it has a
>>> > lot of information like this that you need to know.
>>> >
>>> > --
>>> > Paul
>>> >
>>> Thanks I will read this file and thanks for the information. I known
>>> where the file is I will
>>> add the information then.
>>
>> You may be looking at an older version of MAINTAINERS.  Mathias has only
>> been marked as the maintainer since 3.15.  Which kernel version are you
>> working on?
>>
>> Sarah Sharp
>
I am going to send out my work on the project you sent me I hope it's
Ok if not feel free
to tell me why. I did this against linus's tree but other then that it
should work.
Regards Nick

^ permalink raw reply	[flat|nested] 20+ messages in thread

* Re: Kernel Debugging Support
  2014-08-05  3:18                       ` Nick Krause
@ 2014-08-05  5:32                         ` Nick Krause
  0 siblings, 0 replies; 20+ messages in thread
From: Nick Krause @ 2014-08-05  5:32 UTC (permalink / raw)
  To: Nyman, Mathias; +Cc: Paul Zimmerman, Valdis.Kletnieks, linux-kernel, linux-usb

On Mon, Aug 4, 2014 at 11:18 PM, Nick Krause <xerofoify@gmail.com> wrote:
> On Mon, Aug 4, 2014 at 9:33 PM, Nick Krause <xerofoify@gmail.com> wrote:
>> On Mon, Aug 4, 2014 at 8:12 PM, Sarah Sharp
>> <sarah.a.sharp@linux.intel.com> wrote:
>>> On Mon, Aug 04, 2014 at 07:11:07PM -0400, Nick Krause wrote:
>>>> On Mon, Aug 4, 2014 at 7:03 PM, Paul Zimmerman
>>>> <Paul.Zimmerman@synopsys.com> wrote:
>>>> >> From: Nick Krause [mailto:xerofoify@gmail.com]
>>>
>>> [snip]
>>>
>>>> >> Paul ,
>>>> >> My computer is rather old now as of Sandy Bridge days, so I probably
>>>> >> can't test the patch
>>>> >> on my own machine. However I will look at the code and see if I can
>>>> >> forward port it
>>>> >> against the usb git tree I have a current version of. In addition I
>>>> >> would like the new xhci
>>>> >> maintainers information in  order to send out a patch with the
>>>> >> Maintainer for xhci updated.
>>>> >
>>>> > Sarah already told you who the new maintainer is, and then CCed him
>>>> > on this thread. Hint: There is a file name 'MAINTAINERS' in the root
>>>> > of the kernel tree, which tells you who the maintainers are for all of
>>>> > the subsystems. Please read Documentation/SubmittingPatches, it has a
>>>> > lot of information like this that you need to know.
>>>> >
>>>> > --
>>>> > Paul
>>>> >
>>>> Thanks I will read this file and thanks for the information. I known
>>>> where the file is I will
>>>> add the information then.
>>>
>>> You may be looking at an older version of MAINTAINERS.  Mathias has only
>>> been marked as the maintainer since 3.15.  Which kernel version are you
>>> working on?
>>>
>>> Sarah Sharp
>>
> I am going to send out my work on the project you sent me I hope it's
> Ok if not feel free
> to tell me why. I did this against linus's tree but other then that it
> should work.
> Regards Nick

In addition,
I just sent it a few hours ago. Please let me known tomorrow if it's fine.
I am assuming based off my other work it's not.
Nick

^ permalink raw reply	[flat|nested] 20+ messages in thread

end of thread, other threads:[~2014-08-05  5:32 UTC | newest]

Thread overview: 20+ messages (download: mbox.gz / follow: Atom feed)
-- links below jump to the message on this page --
2014-08-02  4:47 Kernel Debugging Support Nick Krause
2014-08-02 13:48 ` Alan Stern
2014-08-03  1:40   ` Nick Krause
2014-08-04 11:37   ` Austin S Hemmelgarn
2014-08-04 14:21     ` Alan Stern
2014-08-04 14:29       ` Austin S Hemmelgarn
2014-08-04 14:45         ` Richard Weinberger
2014-08-04 16:46 ` Sarah Sharp
2014-08-04 19:07   ` Paul Zimmerman
2014-08-04 19:23     ` Valdis.Kletnieks
2014-08-04 19:40       ` Paul Zimmerman
2014-08-04 20:27         ` Valdis.Kletnieks
2014-08-04 21:55           ` Paul Zimmerman
2014-08-04 22:49             ` Nick Krause
2014-08-04 23:03               ` Paul Zimmerman
2014-08-04 23:11                 ` Nick Krause
2014-08-05  0:12                   ` Sarah Sharp
2014-08-05  1:33                     ` Nick Krause
2014-08-05  3:18                       ` Nick Krause
2014-08-05  5:32                         ` Nick Krause

This is an external index of several public inboxes,
see mirroring instructions on how to clone and mirror
all data and code used by this external index.