Re: [GIT PULL v4.6] MDB Linux Kernel Debugger x86/x86_64

Re: [GIT PULL v4.6] MDB Linux Kernel Debugger x86/x86_64

[Joe Perches]

On Mon, 2016-03-14 at 17:50 -0600, Jeffrey Merkey wrote:
> The following changes since commit b562e44f507e863c6792946e4e1b1449fbbac85d:
> 
>   Linux 4.5 (2016-03-13 21:28:54 -0700)
> 
> are available in the git repository at:
> 
>   https://github.com/jeffmerkey/linux.git tags/mdb-v4.5-signed
> 
> for you to fetch changes up to 2e9c184e1215dca2b4c59c347f40a0986b8e7460:
> 
>   Add MDB Debugger to linux v4.5 (2016-03-14 15:17:44 -0600)

If Linus doesn't pull this, Stephen, could you please add this
tree to -next so it has some testing and validation done?

Maybe the build-bot could do some coverage testing too?

Re: [GIT PULL v4.6] MDB Linux Kernel Debugger x86/x86_64

[Stephen Rothwell]

Hi Joe,

On Mon, 14 Mar 2016 16:57:03 -0700 Joe Perches <joe@perches.com> wrote:
>
> On Mon, 2016-03-14 at 17:50 -0600, Jeffrey Merkey wrote:
> > The following changes since commit b562e44f507e863c6792946e4e1b1449fbbac85d:
> > 
> >   Linux 4.5 (2016-03-13 21:28:54 -0700)
> > 
> > are available in the git repository at:
> > 
> >   https://github.com/jeffmerkey/linux.git tags/mdb-v4.5-signed
> > 
> > for you to fetch changes up to 2e9c184e1215dca2b4c59c347f40a0986b8e7460:
> > 
> >   Add MDB Debugger to linux v4.5 (2016-03-14 15:17:44 -0600)  
> 
> If Linus doesn't pull this, Stephen, could you please add this
> tree to -next so it has some testing and validation done?

Well, I really need a request from the ongoing maintainer and also some
indication of which kernel release (if any) it is likely to be merged
into ...

As a general rule, I do not add trees to linux-next during the merge
window (there have been some special cases when something was going in
during that merge window).

I do note that the single commit in that tag has no Signed-off-by,
Reviewed-by or Acked-by tags at all.  As such I can't see Linus merging
it as is.  The commit message also has no detail at all.  It is also
based on v4.5 which was only released yesterday.
-- 
Cheers,
Stephen Rothwell

Re: [GIT PULL v4.6] MDB Linux Kernel Debugger x86/x86_64

[Jeffrey Merkey]

On 3/14/16, Stephen Rothwell <sfr@canb.auug.org.au> wrote:
> Hi Joe,
>
> On Mon, 14 Mar 2016 16:57:03 -0700 Joe Perches <joe@perches.com> wrote:
>>
>> On Mon, 2016-03-14 at 17:50 -0600, Jeffrey Merkey wrote:
>> > The following changes since commit
>> > b562e44f507e863c6792946e4e1b1449fbbac85d:
>> >
>> >   Linux 4.5 (2016-03-13 21:28:54 -0700)
>> >
>> > are available in the git repository at:
>> >
>> >   https://github.com/jeffmerkey/linux.git tags/mdb-v4.5-signed
>> >
>> > for you to fetch changes up to
>> > 2e9c184e1215dca2b4c59c347f40a0986b8e7460:
>> >
>> >   Add MDB Debugger to linux v4.5 (2016-03-14 15:17:44 -0600)
>>
>> If Linus doesn't pull this, Stephen, could you please add this
>> tree to -next so it has some testing and validation done?
>
> Well, I really need a request from the ongoing maintainer and also some
> indication of which kernel release (if any) it is likely to be merged
> into ...
>
> As a general rule, I do not add trees to linux-next during the merge
> window (there have been some special cases when something was going in
> during that merge window).
>
> I do note that the single commit in that tag has no Signed-off-by,
> Reviewed-by or Acked-by tags at all.  As such I can't see Linus merging
> it as is.  The commit message also has no detail at all.  It is also
> based on v4.5 which was only released yesterday.
> --
> Cheers,
> Stephen Rothwell
>

Hi Stephen,

I was sure I told git to put a sign-off line.  Well, I'll go fix that
and amend the commit as signed.  Don't know what happened there.  Are
you supposed to say

git commit -s -a -v -S

I just used

git commit -S -a -v

I'll amend that commit.  Folks can review and discuss on this thread.

Jeff

Re: [GIT PULL v4.6] MDB Linux Kernel Debugger x86/x86_64

[Stephen Rothwell]

Hi Jeff,

On Mon, 14 Mar 2016 18:40:37 -0600 Jeffrey Merkey <jeffmerkey@gmail.com> wrote:
>
> I was sure I told git to put a sign-off line.  Well, I'll go fix that
> and amend the commit as signed.  Don't know what happened there.  Are
> you supposed to say
> 
> git commit -s -a -v -S
> 
> I just used
> 
> git commit -S -a -v
> 
> I'll amend that commit.  Folks can review and discuss on this thread.

We don't generally PGP (GPG) sign commits in the kernel tree (so "-S"
is not required), just tags.  However we always require that anyone who
handles a patch adds a Signed-off-by line to the final commit.  See
Documentation/SubmittingPatches Section 11.

-- 
Cheers,
Stephen Rothwell

Re: [GIT PULL v4.6] MDB Linux Kernel Debugger x86/x86_64

[Theodore Ts'o]

On Tue, Mar 15, 2016 at 01:03:39PM +1100, Stephen Rothwell wrote:
> We don't generally PGP (GPG) sign commits in the kernel tree (so "-S"
> is not required), just tags.  However we always require that anyone who
> handles a patch adds a Signed-off-by line to the final commit.  See
> Documentation/SubmittingPatches Section 11.

In general all commits should have a Signed-Off-By line added.  Once
the git branch gets merged, it's hard to tell what is the final commit
and what isn't, and in general different commits will have different
people needing to vouch for the origins for the contents of that commit.

Cheers,

							- Ted
							

Re: [GIT PULL v4.6] MDB Linux Kernel Debugger x86/x86_64

[Jeffrey Merkey]

On 3/15/16, Theodore Ts'o <tytso@mit.edu> wrote:
> On Tue, Mar 15, 2016 at 01:03:39PM +1100, Stephen Rothwell wrote:
>> We don't generally PGP (GPG) sign commits in the kernel tree (so "-S"
>> is not required), just tags.  However we always require that anyone who
>> handles a patch adds a Signed-off-by line to the final commit.  See
>> Documentation/SubmittingPatches Section 11.
>
> In general all commits should have a Signed-Off-By line added.  Once
> the git branch gets merged, it's hard to tell what is the final commit
> and what isn't, and in general different commits will have different
> people needing to vouch for the origins for the contents of that commit.
>
> Cheers,
>
> 							- Ted
> 							
>

Hi Ted,

I will repost this pull request with a signed-off by line for Linus to
consider.    I am not certain who all should be included in the review
and I have to be careful how many email recipients I copy.   I will
post to the folks Joe Perches copied.

Jeff

Re: [GIT PULL v4.6] MDB Linux Kernel Debugger x86/x86_64

[Jeffrey Merkey]

On 3/16/16, Jeffrey Merkey <jeffmerkey@gmail.com> wrote:
> On 3/15/16, Theodore Ts'o <tytso@mit.edu> wrote:
>> On Tue, Mar 15, 2016 at 01:03:39PM +1100, Stephen Rothwell wrote:
>>> We don't generally PGP (GPG) sign commits in the kernel tree (so "-S"
>>> is not required), just tags.  However we always require that anyone who
>>> handles a patch adds a Signed-off-by line to the final commit.  See
>>> Documentation/SubmittingPatches Section 11.
>>
>> In general all commits should have a Signed-Off-By line added.  Once
>> the git branch gets merged, it's hard to tell what is the final commit
>> and what isn't, and in general different commits will have different
>> people needing to vouch for the origins for the contents of that commit.
>>
>> Cheers,
>>
>> 							- Ted
>> 							
>>
>
> Hi Ted,
>
> I will repost this pull request with a signed-off by line for Linus to
> consider.    I am not certain who all should be included in the review
> and I have to be careful how many email recipients I copy.   I will
> post to the folks Joe Perches copied.
>
> Jeff
>

Well, Joe updated checkpatch.pl so now there are some more areas of
cleanup I need to do on the code to remove unsigned casts and replace
them with unsigned int.  I will resubmit at the next merge window for
4.7.  Have not heard a word from Linus about this, Hey Linus, please
don't lion-us by throwing us to the lions.  :-)

Jeff

Re: [GIT PULL v4.6] MDB Linux Kernel Debugger x86/x86_64

[Joe Perches]

On Thu, 2016-03-17 at 23:31 -0600, Jeffrey Merkey wrote:
> On 3/16/16, Jeffrey Merkey <jeffmerkey@gmail.com> wrote:
> > On 3/15/16, Theodore Ts'o <tytso@mit.edu> wrote:
> > > On Tue, Mar 15, 2016 at 01:03:39PM +1100, Stephen Rothwell wrote:
> > > > 
> > > > We don't generally PGP (GPG) sign commits in the kernel tree (so "-S"
> > > > is not required), just tags.  However we always require that anyone who
> > > > handles a patch adds a Signed-off-by line to the final commit.  See
> > > > Documentation/SubmittingPatches Section 11.
> > > In general all commits should have a Signed-Off-By line added.  Once
> > > the git branch gets merged, it's hard to tell what is the final commit
> > > and what isn't, and in general different commits will have different
> > > people needing to vouch for the origins for the contents of that commit.
[]
> > I will repost this pull request with a signed-off by line for Linus to
> > consider.    I am not certain who all should be included in the review
> > and I have to be careful how many email recipients I copy.   I will
> > post to the folks Joe Perches copied.
[]
> Well, Joe updated checkpatch.pl so now there are some more areas of
> cleanup I need to do on the code to remove unsigned casts and replace
> them with unsigned int.  I will resubmit at the next merge window for
> 4.7.  Have not heard a word from Linus about this, Hey Linus, please
> don't lion-us by throwing us to the lions.  :-)

I rather doubt Linus is going to pull this code during
this merge window.

I think you should try to get this into -next immediately
after this current merge window closes in a 10 or so days.

I think you don't have to do random cleanups just to
satisfy checkpatch.  Get the code in -next and then
cleanup stuff as you see fit.  There will then be
individual commit changelogs for the mostly whitespace
changes that checkpatch might point out.

Re: [GIT PULL v4.6] MDB Linux Kernel Debugger x86/x86_64

[Jeffrey Merkey]

On 3/17/16, Joe Perches <joe@perches.com> wrote:
> On Thu, 2016-03-17 at 23:31 -0600, Jeffrey Merkey wrote:
>> On 3/16/16, Jeffrey Merkey <jeffmerkey@gmail.com> wrote:
>> > On 3/15/16, Theodore Ts'o <tytso@mit.edu> wrote:
>> > > On Tue, Mar 15, 2016 at 01:03:39PM +1100, Stephen Rothwell wrote:
>> > > >
>> > > > We don't generally PGP (GPG) sign commits in the kernel tree (so
>> > > > "-S"
>> > > > is not required), just tags.  However we always require that anyone
>> > > > who
>> > > > handles a patch adds a Signed-off-by line to the final commit.  See
>> > > > Documentation/SubmittingPatches Section 11.
>> > > In general all commits should have a Signed-Off-By line added.  Once
>> > > the git branch gets merged, it's hard to tell what is the final
>> > > commit
>> > > and what isn't, and in general different commits will have different
>> > > people needing to vouch for the origins for the contents of that
>> > > commit.
> []
>> > I will repost this pull request with a signed-off by line for Linus to
>> > consider.    I am not certain who all should be included in the review
>> > and I have to be careful how many email recipients I copy.   I will
>> > post to the folks Joe Perches copied.
> []
>> Well, Joe updated checkpatch.pl so now there are some more areas of
>> cleanup I need to do on the code to remove unsigned casts and replace
>> them with unsigned int.  I will resubmit at the next merge window for
>> 4.7.  Have not heard a word from Linus about this, Hey Linus, please
>> don't lion-us by throwing us to the lions.  :-)
>
> I rather doubt Linus is going to pull this code during
> this merge window.
>
> I think you should try to get this into -next immediately
> after this current merge window closes in a 10 or so days.
>
> I think you don't have to do random cleanups just to
> satisfy checkpatch.  Get the code in -next and then
> cleanup stuff as you see fit.  There will then be
> individual commit changelogs for the mostly whitespace
> changes that checkpatch might point out.
>
>

OK, then I will setup a pull request for Stephen to pull against the
-next tree.   He can pull it at his convenience.

Jeff

Re: [GIT PULL v4.6] MDB Linux Kernel Debugger x86/x86_64

[Ingo Molnar]

* Stephen Rothwell <sfr@canb.auug.org.au> wrote:

> Hi Joe,
> 
> On Mon, 14 Mar 2016 16:57:03 -0700 Joe Perches <joe@perches.com> wrote:
> >
> > On Mon, 2016-03-14 at 17:50 -0600, Jeffrey Merkey wrote:
> > > The following changes since commit b562e44f507e863c6792946e4e1b1449fbbac85d:
> > > 
> > >   Linux 4.5 (2016-03-13 21:28:54 -0700)
> > > 
> > > are available in the git repository at:
> > > 
> > >   https://github.com/jeffmerkey/linux.git tags/mdb-v4.5-signed
> > > 
> > > for you to fetch changes up to 2e9c184e1215dca2b4c59c347f40a0986b8e7460:
> > > 
> > >   Add MDB Debugger to linux v4.5 (2016-03-14 15:17:44 -0600)  
> > 
> > If Linus doesn't pull this, Stephen, could you please add this
> > tree to -next so it has some testing and validation done?
> 
> Well, I really need a request from the ongoing maintainer and also some
> indication of which kernel release (if any) it is likely to be merged
> into ...

So neither the x86 nor other affected maintainers have acked these changes or have 
agreed to merge it - in fact there are outstanding NAKs against this tree, which 
were not mentioned in the pull request.

Here's one of the objections by me:

   https://lkml.org/lkml/2016/1/29/64

... which technical objections were replied to by Jeff Merkey by accusing me of 
trolling:

  "You were not included on the post since you are not a maintainer of watchdog.c
   so I am confused as to why you are nacking and trolling me on something not in
   your area."

   https://lkml.org/lkml/2016/1/29/397

So this tree is very far from being ready and I'm not convinced we want to merge 
it in its current form. If we merge bits of it then we want to merge it via the 
x86 tree, not a separate tree.

In fact I also have more fundamental objections as well, such as the question of 
unnecessary code duplication: this new MDB debugger overlaps in functionality with 
the already in-tree kgdb+KDB live kernel debugger approach:

I don't think we want to see two overlapping solutions in this area, both of which 
are inferior in their own ways. If then the KDB frontend should be improved: 
features such as disassembler output, more commands and usability improvements 
that can and should be added to the KDB front-end instead. I see nothing in this 
patch that couldn't be added to KDB/KGDB.

All in one, I'd much rather like to see a gradual set of improvement patches to 
KDB, to improve live kernel debugging, than this kind of monolithic, arch 
dependent duplication of functionality.

Thanks,

	Ingo

Re: [GIT PULL v4.6] MDB Linux Kernel Debugger x86/x86_64

[Jeffrey Merkey]

On 3/25/16, Ingo Molnar <mingo@kernel.org> wrote:
>
> * Stephen Rothwell <sfr@canb.auug.org.au> wrote:
>
>> Hi Joe,
>>
>> On Mon, 14 Mar 2016 16:57:03 -0700 Joe Perches <joe@perches.com> wrote:
>> >
>> > On Mon, 2016-03-14 at 17:50 -0600, Jeffrey Merkey wrote:
>> > > The following changes since commit
>> > > b562e44f507e863c6792946e4e1b1449fbbac85d:
>> > >
>> > >   Linux 4.5 (2016-03-13 21:28:54 -0700)
>> > >
>> > > are available in the git repository at:
>> > >
>> > >   https://github.com/jeffmerkey/linux.git tags/mdb-v4.5-signed
>> > >
>> > > for you to fetch changes up to
>> > > 2e9c184e1215dca2b4c59c347f40a0986b8e7460:
>> > >
>> > >   Add MDB Debugger to linux v4.5 (2016-03-14 15:17:44 -0600)
>> >
>> > If Linus doesn't pull this, Stephen, could you please add this
>> > tree to -next so it has some testing and validation done?
>>
>> Well, I really need a request from the ongoing maintainer and also some
>> indication of which kernel release (if any) it is likely to be merged
>> into ...
>
> So neither the x86 nor other affected maintainers have acked these changes
> or have
> agreed to merge it - in fact there are outstanding NAKs against this tree,
> which
> were not mentioned in the pull request.
>
> Here's one of the objections by me:
>
>    https://lkml.org/lkml/2016/1/29/64
>
> ... which technical objections were replied to by Jeff Merkey by accusing me
> of
> trolling:
>
>   "You were not included on the post since you are not a maintainer of
> watchdog.c
>    so I am confused as to why you are nacking and trolling me on something
> not in
>    your area."
>
>    https://lkml.org/lkml/2016/1/29/397
>
> So this tree is very far from being ready and I'm not convinced we want to
> merge
> it in its current form. If we merge bits of it then we want to merge it via
> the
> x86 tree, not a separate tree.
>
> In fact I also have more fundamental objections as well, such as the
> question of
> unnecessary code duplication: this new MDB debugger overlaps in
> functionality with
> the already in-tree kgdb+KDB live kernel debugger approach:
>
> I don't think we want to see two overlapping solutions in this area, both of
> which
> are inferior in their own ways. If then the KDB frontend should be improved:
>
> features such as disassembler output, more commands and usability
> improvements
> that can and should be added to the KDB front-end instead. I see nothing in
> this
> patch that couldn't be added to KDB/KGDB.
>
> All in one, I'd much rather like to see a gradual set of improvement patches
> to
> KDB, to improve live kernel debugging, than this kind of monolithic, arch
> dependent duplication of functionality.
>
> Thanks,
>
> 	Ingo
>

Hi Ingo,

Adding the disassembler to kgb/kgdb would not be all that
straightforward. the architecture of kgdb/kdb does not support it --
it would be significant rewrite of kdb -- in fact, it would have to be
completely restructured .  There are also as you point out some
patches in the debugger you nacked. but removing these is easy.

I also would have to go to whomever is maintaining kdb and to be
honest, I am not all that interested in doing a bunch of work only to
have it rejected or ignored, so the "bait and switch" game of saying
"Please do X for us and we'll think about adding Y" isn't something I
am going to waste my time on.  Linux has more than one file system,
more than one ethernet card driver, so there is no reason it can have
more than one debugger.

Kdb locks up a lot due to the design of it's smp roundup code for
stoping processors, it's a different design totally.

If you want me to do these things I would need free reign and to be
honest, kdb is nowhere near as complete as mdb is.

All that being said if you want me to do as you ask then you need to
show me that you are serious about taking work I do for these areas.

Jeff

Re: [GIT PULL v4.6] MDB Linux Kernel Debugger x86/x86_64

[Jeffrey Merkey]

On 3/25/16, Jeffrey Merkey <jeffmerkey@gmail.com> wrote:
> On 3/25/16, Ingo Molnar <mingo@kernel.org> wrote:
>>
>> * Stephen Rothwell <sfr@canb.auug.org.au> wrote:
>>
>>> Hi Joe,
>>>
>>> On Mon, 14 Mar 2016 16:57:03 -0700 Joe Perches <joe@perches.com> wrote:
>>> >
>>> > On Mon, 2016-03-14 at 17:50 -0600, Jeffrey Merkey wrote:
>>> > > The following changes since commit
>>> > > b562e44f507e863c6792946e4e1b1449fbbac85d:
>>> > >
>>> > >   Linux 4.5 (2016-03-13 21:28:54 -0700)
>>> > >
>>> > > are available in the git repository at:
>>> > >
>>> > >   https://github.com/jeffmerkey/linux.git tags/mdb-v4.5-signed
>>> > >
>>> > > for you to fetch changes up to
>>> > > 2e9c184e1215dca2b4c59c347f40a0986b8e7460:
>>> > >
>>> > >   Add MDB Debugger to linux v4.5 (2016-03-14 15:17:44 -0600)
>>> >
>>> > If Linus doesn't pull this, Stephen, could you please add this
>>> > tree to -next so it has some testing and validation done?
>>>
>>> Well, I really need a request from the ongoing maintainer and also some
>>> indication of which kernel release (if any) it is likely to be merged
>>> into ...
>>
>> So neither the x86 nor other affected maintainers have acked these
>> changes
>> or have
>> agreed to merge it - in fact there are outstanding NAKs against this
>> tree,
>> which
>> were not mentioned in the pull request.
>>
>> Here's one of the objections by me:
>>
>>    https://lkml.org/lkml/2016/1/29/64
>>
>> ... which technical objections were replied to by Jeff Merkey by accusing
>> me
>> of
>> trolling:
>>
>>   "You were not included on the post since you are not a maintainer of
>> watchdog.c
>>    so I am confused as to why you are nacking and trolling me on
>> something
>> not in
>>    your area."
>>
>>    https://lkml.org/lkml/2016/1/29/397
>>
>> So this tree is very far from being ready and I'm not convinced we want
>> to
>> merge
>> it in its current form. If we merge bits of it then we want to merge it
>> via
>> the
>> x86 tree, not a separate tree.
>>
>> In fact I also have more fundamental objections as well, such as the
>> question of
>> unnecessary code duplication: this new MDB debugger overlaps in
>> functionality with
>> the already in-tree kgdb+KDB live kernel debugger approach:
>>
>> I don't think we want to see two overlapping solutions in this area, both
>> of
>> which
>> are inferior in their own ways. If then the KDB frontend should be
>> improved:
>>
>> features such as disassembler output, more commands and usability
>> improvements
>> that can and should be added to the KDB front-end instead. I see nothing
>> in
>> this
>> patch that couldn't be added to KDB/KGDB.
>>
>> All in one, I'd much rather like to see a gradual set of improvement
>> patches
>> to
>> KDB, to improve live kernel debugging, than this kind of monolithic, arch
>> dependent duplication of functionality.
>>
>> Thanks,
>>
>> 	Ingo
>>
>
> Hi Ingo,
>
> Adding the disassembler to kgb/kgdb would not be all that
> straightforward. the architecture of kgdb/kdb does not support it --
> it would be significant rewrite of kdb -- in fact, it would have to be
> completely restructured .  There are also as you point out some
> patches in the debugger you nacked. but removing these is easy.
>
> I also would have to go to whomever is maintaining kdb and to be
> honest, I am not all that interested in doing a bunch of work only to
> have it rejected or ignored, so the "bait and switch" game of saying
> "Please do X for us and we'll think about adding Y" isn't something I
> am going to waste my time on.  Linux has more than one file system,
> more than one ethernet card driver, so there is no reason it can have
> more than one debugger.
>
> Kdb locks up a lot due to the design of it's smp roundup code for
> stoping processors, it's a different design totally.
>
> If you want me to do these things I would need free reign and to be
> honest, kdb is nowhere near as complete as mdb is.
>
> All that being said if you want me to do as you ask then you need to
> show me that you are serious about taking work I do for these areas.
>
> Jeff


In simple terms if you pull mdb as a branch to the x86 tree then I
will do whatever you ask me to do to integrate it into kdb.  You have
to accept the code as is to show me you are serious, then I will adapt
it however you ask me to.

Jeff

Re: [GIT PULL v4.6] MDB Linux Kernel Debugger x86/x86_64

[Jeffrey Merkey]

On 3/25/16, Jeffrey Merkey <jeffmerkey@gmail.com> wrote:
> On 3/25/16, Jeffrey Merkey <jeffmerkey@gmail.com> wrote:
>> On 3/25/16, Ingo Molnar <mingo@kernel.org> wrote:
>>>
>>> * Stephen Rothwell <sfr@canb.auug.org.au> wrote:
>>>
>>>> Hi Joe,
>>>>
>>>> On Mon, 14 Mar 2016 16:57:03 -0700 Joe Perches <joe@perches.com> wrote:
>>>> >
>>>> > On Mon, 2016-03-14 at 17:50 -0600, Jeffrey Merkey wrote:
>>>> > > The following changes since commit
>>>> > > b562e44f507e863c6792946e4e1b1449fbbac85d:
>>>> > >
>>>> > >   Linux 4.5 (2016-03-13 21:28:54 -0700)
>>>> > >
>>>> > > are available in the git repository at:
>>>> > >
>>>> > >   https://github.com/jeffmerkey/linux.git tags/mdb-v4.5-signed
>>>> > >
>>>> > > for you to fetch changes up to
>>>> > > 2e9c184e1215dca2b4c59c347f40a0986b8e7460:
>>>> > >
>>>> > >   Add MDB Debugger to linux v4.5 (2016-03-14 15:17:44 -0600)
>>>> >
>>>> > If Linus doesn't pull this, Stephen, could you please add this
>>>> > tree to -next so it has some testing and validation done?
>>>>
>>>> Well, I really need a request from the ongoing maintainer and also some
>>>> indication of which kernel release (if any) it is likely to be merged
>>>> into ...
>>>
>>> So neither the x86 nor other affected maintainers have acked these
>>> changes
>>> or have
>>> agreed to merge it - in fact there are outstanding NAKs against this
>>> tree,
>>> which
>>> were not mentioned in the pull request.
>>>
>>> Here's one of the objections by me:
>>>
>>>    https://lkml.org/lkml/2016/1/29/64
>>>
>>> ... which technical objections were replied to by Jeff Merkey by
>>> accusing
>>> me
>>> of
>>> trolling:
>>>
>>>   "You were not included on the post since you are not a maintainer of
>>> watchdog.c
>>>    so I am confused as to why you are nacking and trolling me on
>>> something
>>> not in
>>>    your area."
>>>
>>>    https://lkml.org/lkml/2016/1/29/397
>>>
>>> So this tree is very far from being ready and I'm not convinced we want
>>> to
>>> merge
>>> it in its current form. If we merge bits of it then we want to merge it
>>> via
>>> the
>>> x86 tree, not a separate tree.
>>>
>>> In fact I also have more fundamental objections as well, such as the
>>> question of
>>> unnecessary code duplication: this new MDB debugger overlaps in
>>> functionality with
>>> the already in-tree kgdb+KDB live kernel debugger approach:
>>>
>>> I don't think we want to see two overlapping solutions in this area,
>>> both
>>> of
>>> which
>>> are inferior in their own ways. If then the KDB frontend should be
>>> improved:
>>>
>>> features such as disassembler output, more commands and usability
>>> improvements
>>> that can and should be added to the KDB front-end instead. I see nothing
>>> in
>>> this
>>> patch that couldn't be added to KDB/KGDB.
>>>
>>> All in one, I'd much rather like to see a gradual set of improvement
>>> patches
>>> to
>>> KDB, to improve live kernel debugging, than this kind of monolithic,
>>> arch
>>> dependent duplication of functionality.
>>>
>>> Thanks,
>>>
>>> 	Ingo
>>>
>>
>> Hi Ingo,
>>
>> Adding the disassembler to kgb/kgdb would not be all that
>> straightforward. the architecture of kgdb/kdb does not support it --
>> it would be significant rewrite of kdb -- in fact, it would have to be
>> completely restructured .  There are also as you point out some
>> patches in the debugger you nacked. but removing these is easy.
>>
>> I also would have to go to whomever is maintaining kdb and to be
>> honest, I am not all that interested in doing a bunch of work only to
>> have it rejected or ignored, so the "bait and switch" game of saying
>> "Please do X for us and we'll think about adding Y" isn't something I
>> am going to waste my time on.  Linux has more than one file system,
>> more than one ethernet card driver, so there is no reason it can have
>> more than one debugger.
>>
>> Kdb locks up a lot due to the design of it's smp roundup code for
>> stoping processors, it's a different design totally.
>>
>> If you want me to do these things I would need free reign and to be
>> honest, kdb is nowhere near as complete as mdb is.
>>
>> All that being said if you want me to do as you ask then you need to
>> show me that you are serious about taking work I do for these areas.
>>
>> Jeff
>
>
> In simple terms if you pull mdb as a branch to the x86 tree then I
> will do whatever you ask me to do to integrate it into kdb.  You have
> to accept the code as is to show me you are serious, then I will adapt
> it however you ask me to.
>
> Jeff
>

I went back and checked the code and as it turns out, none of the
patches you nak'd are in the current branch, there are different
patches there now.   There are two patches you ignored that are in it,
but no record of a Nak for either of them.


Jeff

Re: [GIT PULL v4.6] MDB Linux Kernel Debugger x86/x86_64

[Jeffrey Merkey]

On 3/25/16, Jeffrey Merkey <jeffmerkey@gmail.com> wrote:
> On 3/25/16, Jeffrey Merkey <jeffmerkey@gmail.com> wrote:
>> On 3/25/16, Jeffrey Merkey <jeffmerkey@gmail.com> wrote:
>>> On 3/25/16, Ingo Molnar <mingo@kernel.org> wrote:
>>>>
>>>> * Stephen Rothwell <sfr@canb.auug.org.au> wrote:
>>>>
>>>>> Hi Joe,
>>>>>
>>>>> On Mon, 14 Mar 2016 16:57:03 -0700 Joe Perches <joe@perches.com>
>>>>> wrote:
>>>>> >
>>>>> > On Mon, 2016-03-14 at 17:50 -0600, Jeffrey Merkey wrote:
>>>>> > > The following changes since commit
>>>>> > > b562e44f507e863c6792946e4e1b1449fbbac85d:
>>>>> > >
>>>>> > >   Linux 4.5 (2016-03-13 21:28:54 -0700)
>>>>> > >
>>>>> > > are available in the git repository at:
>>>>> > >
>>>>> > >   https://github.com/jeffmerkey/linux.git tags/mdb-v4.5-signed
>>>>> > >
>>>>> > > for you to fetch changes up to
>>>>> > > 2e9c184e1215dca2b4c59c347f40a0986b8e7460:
>>>>> > >
>>>>> > >   Add MDB Debugger to linux v4.5 (2016-03-14 15:17:44 -0600)
>>>>> >
>>>>> > If Linus doesn't pull this, Stephen, could you please add this
>>>>> > tree to -next so it has some testing and validation done?
>>>>>
>>>>> Well, I really need a request from the ongoing maintainer and also
>>>>> some
>>>>> indication of which kernel release (if any) it is likely to be merged
>>>>> into ...
>>>>
>>>> So neither the x86 nor other affected maintainers have acked these
>>>> changes
>>>> or have
>>>> agreed to merge it - in fact there are outstanding NAKs against this
>>>> tree,
>>>> which
>>>> were not mentioned in the pull request.
>>>>
>>>> Here's one of the objections by me:
>>>>
>>>>    https://lkml.org/lkml/2016/1/29/64
>>>>
>>>> ... which technical objections were replied to by Jeff Merkey by
>>>> accusing
>>>> me
>>>> of
>>>> trolling:
>>>>
>>>>   "You were not included on the post since you are not a maintainer of
>>>> watchdog.c
>>>>    so I am confused as to why you are nacking and trolling me on
>>>> something
>>>> not in
>>>>    your area."
>>>>
>>>>    https://lkml.org/lkml/2016/1/29/397
>>>>
>>>> So this tree is very far from being ready and I'm not convinced we want
>>>> to
>>>> merge
>>>> it in its current form. If we merge bits of it then we want to merge it
>>>> via
>>>> the
>>>> x86 tree, not a separate tree.
>>>>
>>>> In fact I also have more fundamental objections as well, such as the
>>>> question of
>>>> unnecessary code duplication: this new MDB debugger overlaps in
>>>> functionality with
>>>> the already in-tree kgdb+KDB live kernel debugger approach:
>>>>
>>>> I don't think we want to see two overlapping solutions in this area,
>>>> both
>>>> of
>>>> which
>>>> are inferior in their own ways. If then the KDB frontend should be
>>>> improved:
>>>>
>>>> features such as disassembler output, more commands and usability
>>>> improvements
>>>> that can and should be added to the KDB front-end instead. I see
>>>> nothing
>>>> in
>>>> this
>>>> patch that couldn't be added to KDB/KGDB.
>>>>
>>>> All in one, I'd much rather like to see a gradual set of improvement
>>>> patches
>>>> to
>>>> KDB, to improve live kernel debugging, than this kind of monolithic,
>>>> arch
>>>> dependent duplication of functionality.
>>>>
>>>> Thanks,
>>>>
>>>> 	Ingo
>>>>
>>>
>>> Hi Ingo,
>>>
>>> Adding the disassembler to kgb/kgdb would not be all that
>>> straightforward. the architecture of kgdb/kdb does not support it --
>>> it would be significant rewrite of kdb -- in fact, it would have to be
>>> completely restructured .  There are also as you point out some
>>> patches in the debugger you nacked. but removing these is easy.
>>>
>>> I also would have to go to whomever is maintaining kdb and to be
>>> honest, I am not all that interested in doing a bunch of work only to
>>> have it rejected or ignored, so the "bait and switch" game of saying
>>> "Please do X for us and we'll think about adding Y" isn't something I
>>> am going to waste my time on.  Linux has more than one file system,
>>> more than one ethernet card driver, so there is no reason it can have
>>> more than one debugger.
>>>
>>> Kdb locks up a lot due to the design of it's smp roundup code for
>>> stoping processors, it's a different design totally.
>>>
>>> If you want me to do these things I would need free reign and to be
>>> honest, kdb is nowhere near as complete as mdb is.
>>>
>>> All that being said if you want me to do as you ask then you need to
>>> show me that you are serious about taking work I do for these areas.
>>>
>>> Jeff
>>
>>
>> In simple terms if you pull mdb as a branch to the x86 tree then I
>> will do whatever you ask me to do to integrate it into kdb.  You have
>> to accept the code as is to show me you are serious, then I will adapt
>> it however you ask me to.
>>
>> Jeff
>>
>
> I went back and checked the code and as it turns out, none of the
> patches you nak'd are in the current branch, there are different
> patches there now.   There are two patches you ignored that are in it,
> but no record of a Nak for either of them.
>
>
> Jeff
>


Signed-Off-By:  Jeffrey Merkey <jeffmerkey@gmail.com>

Re: [GIT PULL v4.6] MDB Linux Kernel Debugger x86/x86_64

[Stephen Rothwell]

Hi Jeff,

On Fri, 25 Mar 2016 17:01:27 -0600 Jeffrey Merkey <jeffmerkey@gmail.com> wrote:
> 
> I went back and checked the code and as it turns out, none of the
> patches you nak'd are in the current branch, there are different
> patches there now.   There are two patches you ignored that are in it,
> but no record of a Nak for either of them.

OK, so one obvious problem is that the tree you want merged has a
single patch in it and the diffstat looks like this:

 Documentation/sysrq.txt                    |    2 +-
 MAINTAINERS                                |    6 +
 arch/x86/include/asm/bug.h                 |    9 +-
 arch/x86/include/uapi/asm/debugreg.h       |    1 +
 arch/x86/kernel/Makefile                   |    1 +
 arch/x86/kernel/apic/io_apic.c             |    2 +
 arch/x86/kernel/debug/Makefile             |    3 +
 arch/x86/kernel/debug/mdb/Makefile         |    6 +
 arch/x86/kernel/debug/mdb/Makefile.local   |  106 +
 arch/x86/kernel/debug/mdb/mdb-base.c       | 3293 +++++++++++++
 arch/x86/kernel/debug/mdb/mdb-base.h       |  447 ++
 arch/x86/kernel/debug/mdb/mdb-ia-apic.c    |  243 +
 arch/x86/kernel/debug/mdb/mdb-ia-proc.h    |  819 ++++
 arch/x86/kernel/debug/mdb/mdb-ia-support.c | 5342 +++++++++++++++++++++
 arch/x86/kernel/debug/mdb/mdb-ia-support.h |   76 +
 arch/x86/kernel/debug/mdb/mdb-ia.c         | 6887 ++++++++++++++++++++++++++++
 arch/x86/kernel/debug/mdb/mdb-ia.h         |  209 +
 arch/x86/kernel/debug/mdb/mdb-keyboard.h   |  127 +
 arch/x86/kernel/debug/mdb/mdb-list.c       |  534 +++
 arch/x86/kernel/debug/mdb/mdb-list.h       |   96 +
 arch/x86/kernel/debug/mdb/mdb-logic.c      | 2118 +++++++++
 arch/x86/kernel/debug/mdb/mdb-main.c       |  786 ++++
 arch/x86/kernel/debug/mdb/mdb-os.c         | 1474 ++++++
 arch/x86/kernel/debug/mdb/mdb-os.h         |  141 +
 arch/x86/kernel/debug/mdb/mdb-proc.h       |  179 +
 arch/x86/kernel/debug/mdb/mdb.h            |   40 +
 arch/x86/kernel/dumpstack_32.c             |    6 +-
 arch/x86/kernel/dumpstack_64.c             |   18 +
 arch/x86/kernel/hw_breakpoint.c            |   69 +-
 arch/x86/kernel/reboot.c                   |    1 +
 arch/x86/kernel/traps.c                    |   14 +
 drivers/tty/vt/vt.c                        |    4 +
 include/asm-generic/bug.h                  |    4 +
 include/linux/console.h                    |    4 +
 kernel/debug/kdb/kdb_debugger.c            |    2 +-
 kernel/events/hw_breakpoint.c              |    2 +
 kernel/extable.c                           |    1 +
 kernel/kallsyms.c                          |   45 +
 kernel/module.c                            |   43 +
 kernel/rcu/tree.c                          |    1 +
 kernel/sched/core.c                        |   13 +-
 kernel/time/clocksource.c                  |    1 +
 kernel/watchdog.c                          |   17 +-
 lib/Kconfig.debug                          |   66 +
 44 files changed, 23240 insertions(+), 18 deletions(-)

Having it in that form makes it pretty hard for anyone to review ...

If you have a set if incremental patches, maybe you should post those
instead.

I am afraid that if the maintainers affected by this code will not
merge it, I cannot justify putting it in linux-next myself.
-- 
Cheers,
Stephen Rothwell

Re: [GIT PULL v4.6] MDB Linux Kernel Debugger x86/x86_64

[Jeffrey Merkey]

On 3/25/16, Stephen Rothwell <sfr@canb.auug.org.au> wrote:
> Hi Jeff,
>
> On Fri, 25 Mar 2016 17:01:27 -0600 Jeffrey Merkey <jeffmerkey@gmail.com>
> wrote:
>>
>> I went back and checked the code and as it turns out, none of the
>> patches you nak'd are in the current branch, there are different
>> patches there now.   There are two patches you ignored that are in it,
>> but no record of a Nak for either of them.
>
> OK, so one obvious problem is that the tree you want merged has a
> single patch in it and the diffstat looks like this:
>
>  Documentation/sysrq.txt                    |    2 +-
>  MAINTAINERS                                |    6 +
>  arch/x86/include/asm/bug.h                 |    9 +-
>  arch/x86/include/uapi/asm/debugreg.h       |    1 +
>  arch/x86/kernel/Makefile                   |    1 +
>  arch/x86/kernel/apic/io_apic.c             |    2 +
>  arch/x86/kernel/debug/Makefile             |    3 +
>  arch/x86/kernel/debug/mdb/Makefile         |    6 +
>  arch/x86/kernel/debug/mdb/Makefile.local   |  106 +
>  arch/x86/kernel/debug/mdb/mdb-base.c       | 3293 +++++++++++++
>  arch/x86/kernel/debug/mdb/mdb-base.h       |  447 ++
>  arch/x86/kernel/debug/mdb/mdb-ia-apic.c    |  243 +
>  arch/x86/kernel/debug/mdb/mdb-ia-proc.h    |  819 ++++
>  arch/x86/kernel/debug/mdb/mdb-ia-support.c | 5342 +++++++++++++++++++++
>  arch/x86/kernel/debug/mdb/mdb-ia-support.h |   76 +
>  arch/x86/kernel/debug/mdb/mdb-ia.c         | 6887
> ++++++++++++++++++++++++++++
>  arch/x86/kernel/debug/mdb/mdb-ia.h         |  209 +
>  arch/x86/kernel/debug/mdb/mdb-keyboard.h   |  127 +
>  arch/x86/kernel/debug/mdb/mdb-list.c       |  534 +++
>  arch/x86/kernel/debug/mdb/mdb-list.h       |   96 +
>  arch/x86/kernel/debug/mdb/mdb-logic.c      | 2118 +++++++++
>  arch/x86/kernel/debug/mdb/mdb-main.c       |  786 ++++
>  arch/x86/kernel/debug/mdb/mdb-os.c         | 1474 ++++++
>  arch/x86/kernel/debug/mdb/mdb-os.h         |  141 +
>  arch/x86/kernel/debug/mdb/mdb-proc.h       |  179 +
>  arch/x86/kernel/debug/mdb/mdb.h            |   40 +
>  arch/x86/kernel/dumpstack_32.c             |    6 +-
>  arch/x86/kernel/dumpstack_64.c             |   18 +
>  arch/x86/kernel/hw_breakpoint.c            |   69 +-
>  arch/x86/kernel/reboot.c                   |    1 +
>  arch/x86/kernel/traps.c                    |   14 +
>  drivers/tty/vt/vt.c                        |    4 +
>  include/asm-generic/bug.h                  |    4 +
>  include/linux/console.h                    |    4 +
>  kernel/debug/kdb/kdb_debugger.c            |    2 +-
>  kernel/events/hw_breakpoint.c              |    2 +
>  kernel/extable.c                           |    1 +
>  kernel/kallsyms.c                          |   45 +
>  kernel/module.c                            |   43 +
>  kernel/rcu/tree.c                          |    1 +
>  kernel/sched/core.c                        |   13 +-
>  kernel/time/clocksource.c                  |    1 +
>  kernel/watchdog.c                          |   17 +-
>  lib/Kconfig.debug                          |   66 +
>  44 files changed, 23240 insertions(+), 18 deletions(-)
>
> Having it in that form makes it pretty hard for anyone to review ...
>
> If you have a set if incremental patches, maybe you should post those
> instead.
>
> I am afraid that if the maintainers affected by this code will not
> merge it, I cannot justify putting it in linux-next myself.
> --
> Cheers,
> Stephen Rothwell
>

I am not going to waste time arguing with the maintainers and chasing
after them.  I have a debugger, it has lots of users and a big
installed base that goes back many years.  So long as they can get it
and use it, things are cool.  Putting it in Linux is actually more of
a pain than just doing what I have been over the years and maintaining
it alongside linux.

Each merge cycle it will be submitted for the linux community, but
like I said, I am not wasting time with folks who are not my customers
and or really not that interested in it.

I already played the bait and switch game with Ingo once before and I
did a lot a work and it was ignored, so he can waste someone else's
time.  Linux is only as good as the people maintaining it.

Jeff

Re: [GIT PULL v4.6] MDB Linux Kernel Debugger x86/x86_64

[Stephen Rothwell]

Hi Ingo,

On Fri, 25 Mar 2016 09:36:21 +0100 Ingo Molnar <mingo@kernel.org> wrote:
>
> So neither the x86 nor other affected maintainers have acked these changes or have 
> agreed to merge it - in fact there are outstanding NAKs against this tree, which 
> were not mentioned in the pull request.
> 
> Here's one of the objections by me:
> 
>    https://lkml.org/lkml/2016/1/29/64
> 
> ... which technical objections were replied to by Jeff Merkey by accusing me of 
> trolling:
> 
>   "You were not included on the post since you are not a maintainer of watchdog.c
>    so I am confused as to why you are nacking and trolling me on something not in
>    your area."
> 
>    https://lkml.org/lkml/2016/1/29/397
> 
> So this tree is very far from being ready and I'm not convinced we want to merge 
> it in its current form. If we merge bits of it then we want to merge it via the 
> x86 tree, not a separate tree.
> 
> In fact I also have more fundamental objections as well, such as the question of 
> unnecessary code duplication: this new MDB debugger overlaps in functionality with 
> the already in-tree kgdb+KDB live kernel debugger approach:
> 
> I don't think we want to see two overlapping solutions in this area, both of which 
> are inferior in their own ways. If then the KDB frontend should be improved: 
> features such as disassembler output, more commands and usability improvements 
> that can and should be added to the KDB front-end instead. I see nothing in this 
> patch that couldn't be added to KDB/KGDB.
> 
> All in one, I'd much rather like to see a gradual set of improvement patches to 
> KDB, to improve live kernel debugging, than this kind of monolithic, arch 
> dependent duplication of functionality.

Thanks for your input clarifying the situation.
-- 
Cheers,
Stephen Rothwell