2018-02-12 19:36:35

by Sander Eikelenboom

[permalink] [raw]
Subject: Linux 4.16-rc1: regression bisected, Debian kernel package tool make-kpkg stalls indefinitely during kernel build due to commit "kconfig: remove check_stdin()"

L.S.,

The Debian kernel-package tool make-kpkg for easy building of upstream kernels on Debian fails with linux 4.16-rc1.

The tool (perl script) while invoked with:
make-kpkg --initrd --append_to_version -20180212 kernel_image

On a git tree with a .config from the previous kernel release, so new KConfig questions have to be asked on new or changed options.

The script stalls indefinitely while it seems to be excuting:
exec make kpkg_version=13.018+nmu1 -f /usr/share/kernel-package/ruleset/minimal.mk debian APPEND_TO_VERSION=-t440s-20180212 INITRD=YES

After using ctrl-c to break out it, i get:
^CFailed to create a ./debian directory: No such file or directory at /usr/bin/make-kpkg line 970.


Bisection turned up as culprit:
commit d2a04648a5dbc3d1d043b35257364f0197d4d868
kconfig: remove check_stdin()

Except silentoldconfig, valid_stdin is 1, so check_stdin() is no-op.

oldconfig and silentoldconfig work almost in the same way except that
the latter generates additional files under include/. Both ask users
for input for new symbols.

I do not know why only silentoldconfig requires stdio be tty.

$ rm -f .config; touch .config
$ yes "" | make oldconfig > stdout
$ rm -f .config; touch .config
$ yes "" | make silentoldconfig > stdout
make[1]: *** [silentoldconfig] Error 1
make: *** [silentoldconfig] Error 2
$ tail -n 4 stdout
Console input/output is redirected. Run 'make oldconfig' to update configuration.

scripts/kconfig/Makefile:40: recipe for target 'silentoldconfig' failed
Makefile:507: recipe for target 'silentoldconfig' failed

Redirection is useful, for example, for testing where we want to give
particular key inputs from a test file, then check the result.

Signed-off-by: Masahiro Yamada <[email protected]>
Reviewed-by: Ulf Magnusson <[email protected]>

Reverting this specific commit makes make-kpkg work again as usual.

Version of the kernel-package used:
ii kernel-package 13.018+nmu1


I also cc'ed the Debian developer who maintains the kernel-package package: Manoj Srivastava

--
Sander



2018-02-13 03:02:54

by Woody Suwalski

[permalink] [raw]
Subject: Re: Linux 4.16-rc1: regression bisected, Debian kernel package tool make-kpkg stalls indefinitely during kernel build due to commit "kconfig: remove check_stdin()"

Sander Eikelenboom wrote:
> L.S.,
>
> The Debian kernel-package tool make-kpkg for easy building of upstream kernels on Debian fails with linux 4.16-rc1.
>
> The tool (perl script) while invoked with:
> make-kpkg --initrd --append_to_version -20180212 kernel_image
>
> On a git tree with a .config from the previous kernel release, so new KConfig questions have to be asked on new or changed options.
>
> The script stalls indefinitely while it seems to be excuting:
> exec make kpkg_version=13.018+nmu1 -f /usr/share/kernel-package/ruleset/minimal.mk debian APPEND_TO_VERSION=-t440s-20180212 INITRD=YES
>
> After using ctrl-c to break out it, i get:
> ^CFailed to create a ./debian directory: No such file or directory at /usr/bin/make-kpkg line 970.
>
>
> Bisection turned up as culprit:
> commit d2a04648a5dbc3d1d043b35257364f0197d4d868
> kconfig: remove check_stdin()
>
> Except silentoldconfig, valid_stdin is 1, so check_stdin() is no-op.
>
> oldconfig and silentoldconfig work almost in the same way except that
> the latter generates additional files under include/. Both ask users
> for input for new symbols.
>
> I do not know why only silentoldconfig requires stdio be tty.
>
> $ rm -f .config; touch .config
> $ yes "" | make oldconfig > stdout
> $ rm -f .config; touch .config
> $ yes "" | make silentoldconfig > stdout
> make[1]: *** [silentoldconfig] Error 1
> make: *** [silentoldconfig] Error 2
> $ tail -n 4 stdout
> Console input/output is redirected. Run 'make oldconfig' to update configuration.
>
> scripts/kconfig/Makefile:40: recipe for target 'silentoldconfig' failed
> Makefile:507: recipe for target 'silentoldconfig' failed
>
> Redirection is useful, for example, for testing where we want to give
> particular key inputs from a test file, then check the result.
>
> Signed-off-by: Masahiro Yamada <[email protected]>
> Reviewed-by: Ulf Magnusson <[email protected]>
>
> Reverting this specific commit makes make-kpkg work again as usual.
>
> Version of the kernel-package used:
> ii kernel-package 13.018+nmu1
>
>
> I also cc'ed the Debian developer who maintains the kernel-package package: Manoj Srivastava
>
> --
> Sander
>
I have noticed today the same - the kernel-build blockage was in (as I
recall)
srcipts/kconfig/conf -s --silentoldconfig Kbuild

I have bypassed it by regenerating the .config "by hand"...

Woody

2018-02-13 04:11:28

by Masahiro Yamada

[permalink] [raw]
Subject: Re: Linux 4.16-rc1: regression bisected, Debian kernel package tool make-kpkg stalls indefinitely during kernel build due to commit "kconfig: remove check_stdin()"

2018-02-13 12:00 GMT+09:00 Woody Suwalski <[email protected]>:
> Sander Eikelenboom wrote:
>>
>> L.S.,
>>
>> The Debian kernel-package tool make-kpkg for easy building of upstream
>> kernels on Debian fails with linux 4.16-rc1.
>>
>> The tool (perl script) while invoked with:
>> make-kpkg --initrd --append_to_version -20180212 kernel_image
>>
>> On a git tree with a .config from the previous kernel release, so new
>> KConfig questions have to be asked on new or changed options.
>>
>> The script stalls indefinitely while it seems to be excuting:
>> exec make kpkg_version=13.018+nmu1 -f
>> /usr/share/kernel-package/ruleset/minimal.mk debian
>> APPEND_TO_VERSION=-t440s-20180212 INITRD=YES
>>
>> After using ctrl-c to break out it, i get:
>> ^CFailed to create a ./debian directory: No such file or directory at
>> /usr/bin/make-kpkg line 970.
>>
>> Bisection turned up as culprit:
>> commit d2a04648a5dbc3d1d043b35257364f0197d4d868
>> kconfig: remove check_stdin()
>> Except silentoldconfig, valid_stdin is 1, so check_stdin() is
>> no-op.
>> oldconfig and silentoldconfig work almost in the same way except
>> that
>> the latter generates additional files under include/. Both ask users
>> for input for new symbols.
>> I do not know why only silentoldconfig requires stdio be tty.
>> $ rm -f .config; touch .config
>> $ yes "" | make oldconfig > stdout
>> $ rm -f .config; touch .config
>> $ yes "" | make silentoldconfig > stdout
>> make[1]: *** [silentoldconfig] Error 1
>> make: *** [silentoldconfig] Error 2
>> $ tail -n 4 stdout
>> Console input/output is redirected. Run 'make oldconfig' to update
>> configuration.
>> scripts/kconfig/Makefile:40: recipe for target
>> 'silentoldconfig' failed
>> Makefile:507: recipe for target 'silentoldconfig' failed
>> Redirection is useful, for example, for testing where we want to
>> give
>> particular key inputs from a test file, then check the result.
>> Signed-off-by: Masahiro Yamada <[email protected]>
>> Reviewed-by: Ulf Magnusson <[email protected]>
>>
>> Reverting this specific commit makes make-kpkg work again as usual.
>>
>> Version of the kernel-package used:
>> ii kernel-package
>> 13.018+nmu1
>>
>>
>> I also cc'ed the Debian developer who maintains the kernel-package
>> package: Manoj Srivastava
>>
>> --
>> Sander
>>
> I have noticed today the same - the kernel-build blockage was in (as I
> recall)
> srcipts/kconfig/conf -s --silentoldconfig Kbuild
>
> I have bypassed it by regenerating the .config "by hand"...


silentoldconfig asks you values for new symbols.
So, you must answer questions to proceed.


How does 'make-kpkg' handle silentoldconfig?

Re-direct stdio, then make it forcibly fail?



--
Best Regards
Masahiro Yamada

2018-02-13 10:01:55

by Sander Eikelenboom

[permalink] [raw]
Subject: Re: Linux 4.16-rc1: regression bisected, Debian kernel package tool make-kpkg stalls indefinitely during kernel build due to commit "kconfig: remove check_stdin()"

On 13/02/18 05:09, Masahiro Yamada wrote:
> 2018-02-13 12:00 GMT+09:00 Woody Suwalski <[email protected]>:
>> Sander Eikelenboom wrote:
>>>
>>> L.S.,
>>>
>>> The Debian kernel-package tool make-kpkg for easy building of upstream
>>> kernels on Debian fails with linux 4.16-rc1.
>>>
>>> The tool (perl script) while invoked with:
>>> make-kpkg --initrd --append_to_version -20180212 kernel_image
>>>
>>> On a git tree with a .config from the previous kernel release, so new
>>> KConfig questions have to be asked on new or changed options.
>>>
>>> The script stalls indefinitely while it seems to be excuting:
>>> exec make kpkg_version=13.018+nmu1 -f
>>> /usr/share/kernel-package/ruleset/minimal.mk debian
>>> APPEND_TO_VERSION=-t440s-20180212 INITRD=YES
>>>
>>> After using ctrl-c to break out it, i get:
>>> ^CFailed to create a ./debian directory: No such file or directory at
>>> /usr/bin/make-kpkg line 970.
>>>
>>> Bisection turned up as culprit:
>>> commit d2a04648a5dbc3d1d043b35257364f0197d4d868
>>> kconfig: remove check_stdin()
>>> Except silentoldconfig, valid_stdin is 1, so check_stdin() is
>>> no-op.
>>> oldconfig and silentoldconfig work almost in the same way except
>>> that
>>> the latter generates additional files under include/. Both ask users
>>> for input for new symbols.
>>> I do not know why only silentoldconfig requires stdio be tty.
>>> $ rm -f .config; touch .config
>>> $ yes "" | make oldconfig > stdout
>>> $ rm -f .config; touch .config
>>> $ yes "" | make silentoldconfig > stdout
>>> make[1]: *** [silentoldconfig] Error 1
>>> make: *** [silentoldconfig] Error 2
>>> $ tail -n 4 stdout
>>> Console input/output is redirected. Run 'make oldconfig' to update
>>> configuration.
>>> scripts/kconfig/Makefile:40: recipe for target
>>> 'silentoldconfig' failed
>>> Makefile:507: recipe for target 'silentoldconfig' failed
>>> Redirection is useful, for example, for testing where we want to
>>> give
>>> particular key inputs from a test file, then check the result.
>>> Signed-off-by: Masahiro Yamada <[email protected]>
>>> Reviewed-by: Ulf Magnusson <[email protected]>
>>>
>>> Reverting this specific commit makes make-kpkg work again as usual.
>>>
>>> Version of the kernel-package used:
>>> ii kernel-package
>>> 13.018+nmu1
>>>
>>>
>>> I also cc'ed the Debian developer who maintains the kernel-package
>>> package: Manoj Srivastava
>>>
>>> --
>>> Sander
>>>
>> I have noticed today the same - the kernel-build blockage was in (as I
>> recall)
>> srcipts/kconfig/conf -s --silentoldconfig Kbuild
>>
>> I have bypassed it by regenerating the .config "by hand"...
>
>
> silentoldconfig asks you values for new symbols.
> So, you must answer questions to proceed.

I know, but it stalls before asking the questions.

>
> How does 'make-kpkg' handle silentoldconfig?
>
> Re-direct stdio, then make it forcibly fail?

I don't know, it is a bunch of perl and shell scripts that gets invoked, not the most easy to comprehend if you are not familiar with them. I'm just a user of the tool.

So i would have to defer that question to the Debian package maintainer, hopefully he will chime in.

--
Sander

>
>
>


2018-02-13 11:34:59

by Ulf Magnusson

[permalink] [raw]
Subject: Re: Linux 4.16-rc1: regression bisected, Debian kernel package tool make-kpkg stalls indefinitely during kernel build due to commit "kconfig: remove check_stdin()"

On Tue, Feb 13, 2018 at 11:00:49AM +0100, Sander Eikelenboom wrote:
> On 13/02/18 05:09, Masahiro Yamada wrote:
> > 2018-02-13 12:00 GMT+09:00 Woody Suwalski <[email protected]>:
> >> Sander Eikelenboom wrote:
> >>>
> >>> L.S.,
> >>>
> >>> The Debian kernel-package tool make-kpkg for easy building of upstream
> >>> kernels on Debian fails with linux 4.16-rc1.
> >>>
> >>> The tool (perl script) while invoked with:
> >>> make-kpkg --initrd --append_to_version -20180212 kernel_image
> >>>
> >>> On a git tree with a .config from the previous kernel release, so new
> >>> KConfig questions have to be asked on new or changed options.
> >>>
> >>> The script stalls indefinitely while it seems to be excuting:
> >>> exec make kpkg_version=13.018+nmu1 -f
> >>> /usr/share/kernel-package/ruleset/minimal.mk debian
> >>> APPEND_TO_VERSION=-t440s-20180212 INITRD=YES
> >>>
> >>> After using ctrl-c to break out it, i get:
> >>> ^CFailed to create a ./debian directory: No such file or directory at
> >>> /usr/bin/make-kpkg line 970.
> >>>
> >>> Bisection turned up as culprit:
> >>> commit d2a04648a5dbc3d1d043b35257364f0197d4d868
> >>> kconfig: remove check_stdin()
> >>> Except silentoldconfig, valid_stdin is 1, so check_stdin() is
> >>> no-op.
> >>> oldconfig and silentoldconfig work almost in the same way except
> >>> that
> >>> the latter generates additional files under include/. Both ask users
> >>> for input for new symbols.
> >>> I do not know why only silentoldconfig requires stdio be tty.
> >>> $ rm -f .config; touch .config
> >>> $ yes "" | make oldconfig > stdout
> >>> $ rm -f .config; touch .config
> >>> $ yes "" | make silentoldconfig > stdout
> >>> make[1]: *** [silentoldconfig] Error 1
> >>> make: *** [silentoldconfig] Error 2
> >>> $ tail -n 4 stdout
> >>> Console input/output is redirected. Run 'make oldconfig' to update
> >>> configuration.
> >>> scripts/kconfig/Makefile:40: recipe for target
> >>> 'silentoldconfig' failed
> >>> Makefile:507: recipe for target 'silentoldconfig' failed
> >>> Redirection is useful, for example, for testing where we want to
> >>> give
> >>> particular key inputs from a test file, then check the result.
> >>> Signed-off-by: Masahiro Yamada <[email protected]>
> >>> Reviewed-by: Ulf Magnusson <[email protected]>
> >>>
> >>> Reverting this specific commit makes make-kpkg work again as usual.
> >>>
> >>> Version of the kernel-package used:
> >>> ii kernel-package
> >>> 13.018+nmu1
> >>>
> >>>
> >>> I also cc'ed the Debian developer who maintains the kernel-package
> >>> package: Manoj Srivastava
> >>>
> >>> --
> >>> Sander
> >>>
> >> I have noticed today the same - the kernel-build blockage was in (as I
> >> recall)
> >> srcipts/kconfig/conf -s --silentoldconfig Kbuild
> >>
> >> I have bypassed it by regenerating the .config "by hand"...
> >
> >
> > silentoldconfig asks you values for new symbols.
> > So, you must answer questions to proceed.
>
> I know, but it stalls before asking the questions.
>
> >
> > How does 'make-kpkg' handle silentoldconfig?
> >
> > Re-direct stdio, then make it forcibly fail?
>
> I don't know, it is a bunch of perl and shell scripts that gets invoked, not the most easy to comprehend if you are not familiar with them. I'm just a user of the tool.
>
> So i would have to defer that question to the Debian package maintainer, hopefully he will chime in.
>
> --
> Sander
>
> >
> >
> >
>

Hello,

What the commit does is to make silentoldconfig not immediately exit(1)
when both of the following apply:

1. stdin is from something that's not a terminal

2. New symbols are prompted for

All the outputs (.config and the include/generated/ and include/config/
trees) are generated after the point where silentoldconfig would
previously exit(1), afaics, so the effects of the commit can be
summarized as follows:

* If no new symbols appear (that would be prompted for), the
behavior is exactly the same as before.

(check_stdin() never seems to get called unless a value would
actually be prompted for, which makes sense.)

* If new symbols appear and stdin is a tty, the behavior is also
exactly the same as before.

And finally, the only case where the behavior differs:

* If new symbols appear and stdin is not a tty, the
new behavior is to prompt (to expect e.g. "n"/"m"/"y" from
wherever stdin is coming from).

The old behavior was to exit(1) without generating any output
files.

Hopefully that clarifies it.

The intent of the commit was just to clean up the code a bit, since
there doesn't seem to be a good reason to bail just because stdin
happens to not be a tty (plus it's inconsistent with the way oldconfig
works, which never bailed).

silentoldconfig is something of an internal implementation detail at
this point by the way. It's basically oldconfig + generate the
configuration stuff in include/generated/ and include/config/ that
actually gets used during the build. Normally it's called automatically
as needed when building the kernel.

See https://www.spinics.net/lists/kernel/msg2720574.html for some more
details re. silentoldconfig.

Cheers,
Ulf

2018-02-13 12:36:06

by Ulf Magnusson

[permalink] [raw]
Subject: Re: Linux 4.16-rc1: regression bisected, Debian kernel package tool make-kpkg stalls indefinitely during kernel build due to commit "kconfig: remove check_stdin()"

On Tue, Feb 13, 2018 at 12:33:24PM +0100, Ulf Magnusson wrote:
> On Tue, Feb 13, 2018 at 11:00:49AM +0100, Sander Eikelenboom wrote:
> > On 13/02/18 05:09, Masahiro Yamada wrote:
> > > 2018-02-13 12:00 GMT+09:00 Woody Suwalski <[email protected]>:
> > >> Sander Eikelenboom wrote:
> > >>>
> > >>> L.S.,
> > >>>
> > >>> The Debian kernel-package tool make-kpkg for easy building of upstream
> > >>> kernels on Debian fails with linux 4.16-rc1.
> > >>>
> > >>> The tool (perl script) while invoked with:
> > >>> make-kpkg --initrd --append_to_version -20180212 kernel_image
> > >>>
> > >>> On a git tree with a .config from the previous kernel release, so new
> > >>> KConfig questions have to be asked on new or changed options.
> > >>>
> > >>> The script stalls indefinitely while it seems to be excuting:
> > >>> exec make kpkg_version=13.018+nmu1 -f
> > >>> /usr/share/kernel-package/ruleset/minimal.mk debian
> > >>> APPEND_TO_VERSION=-t440s-20180212 INITRD=YES
> > >>>
> > >>> After using ctrl-c to break out it, i get:
> > >>> ^CFailed to create a ./debian directory: No such file or directory at
> > >>> /usr/bin/make-kpkg line 970.
> > >>>
> > >>> Bisection turned up as culprit:
> > >>> commit d2a04648a5dbc3d1d043b35257364f0197d4d868
> > >>> kconfig: remove check_stdin()
> > >>> Except silentoldconfig, valid_stdin is 1, so check_stdin() is
> > >>> no-op.
> > >>> oldconfig and silentoldconfig work almost in the same way except
> > >>> that
> > >>> the latter generates additional files under include/. Both ask users
> > >>> for input for new symbols.
> > >>> I do not know why only silentoldconfig requires stdio be tty.
> > >>> $ rm -f .config; touch .config
> > >>> $ yes "" | make oldconfig > stdout
> > >>> $ rm -f .config; touch .config
> > >>> $ yes "" | make silentoldconfig > stdout
> > >>> make[1]: *** [silentoldconfig] Error 1
> > >>> make: *** [silentoldconfig] Error 2
> > >>> $ tail -n 4 stdout
> > >>> Console input/output is redirected. Run 'make oldconfig' to update
> > >>> configuration.
> > >>> scripts/kconfig/Makefile:40: recipe for target
> > >>> 'silentoldconfig' failed
> > >>> Makefile:507: recipe for target 'silentoldconfig' failed
> > >>> Redirection is useful, for example, for testing where we want to
> > >>> give
> > >>> particular key inputs from a test file, then check the result.
> > >>> Signed-off-by: Masahiro Yamada <[email protected]>
> > >>> Reviewed-by: Ulf Magnusson <[email protected]>
> > >>>
> > >>> Reverting this specific commit makes make-kpkg work again as usual.
> > >>>
> > >>> Version of the kernel-package used:
> > >>> ii kernel-package
> > >>> 13.018+nmu1
> > >>>
> > >>>
> > >>> I also cc'ed the Debian developer who maintains the kernel-package
> > >>> package: Manoj Srivastava
> > >>>
> > >>> --
> > >>> Sander
> > >>>
> > >> I have noticed today the same - the kernel-build blockage was in (as I
> > >> recall)
> > >> srcipts/kconfig/conf -s --silentoldconfig Kbuild
> > >>
> > >> I have bypassed it by regenerating the .config "by hand"...
> > >
> > >
> > > silentoldconfig asks you values for new symbols.
> > > So, you must answer questions to proceed.
> >
> > I know, but it stalls before asking the questions.
> >
> > >
> > > How does 'make-kpkg' handle silentoldconfig?
> > >
> > > Re-direct stdio, then make it forcibly fail?
> >
> > I don't know, it is a bunch of perl and shell scripts that gets invoked, not the most easy to comprehend if you are not familiar with them. I'm just a user of the tool.
> >
> > So i would have to defer that question to the Debian package maintainer, hopefully he will chime in.
> >
> > --
> > Sander
> >
> > >
> > >
> > >
> >
>
> Hello,
>
> What the commit does is to make silentoldconfig not immediately exit(1)
> when both of the following apply:
>
> 1. stdin is from something that's not a terminal
>
> 2. New symbols are prompted for
>
> All the outputs (.config and the include/generated/ and include/config/
> trees) are generated after the point where silentoldconfig would
> previously exit(1), afaics, so the effects of the commit can be
> summarized as follows:
>
> * If no new symbols appear (that would be prompted for), the
> behavior is exactly the same as before.
>
> (check_stdin() never seems to get called unless a value would
> actually be prompted for, which makes sense.)
>
> * If new symbols appear and stdin is a tty, the behavior is also
> exactly the same as before.
>
> And finally, the only case where the behavior differs:
>
> * If new symbols appear and stdin is not a tty, the
> new behavior is to prompt (to expect e.g. "n"/"m"/"y" from
> wherever stdin is coming from).
>
> The old behavior was to exit(1) without generating any output
> files.
>
> Hopefully that clarifies it.
>
> The intent of the commit was just to clean up the code a bit, since
> there doesn't seem to be a good reason to bail just because stdin
> happens to not be a tty (plus it's inconsistent with the way oldconfig
> works, which never bailed).
>
> silentoldconfig is something of an internal implementation detail at
> this point by the way. It's basically oldconfig + generate the
> configuration stuff in include/generated/ and include/config/ that
> actually gets used during the build. Normally it's called automatically
> as needed when building the kernel.
>
> See https://www.spinics.net/lists/kernel/msg2720574.html for some more
> details re. silentoldconfig.
>
> Cheers,
> Ulf

By the way: If you can figure out a reason for why that stdin check was
there before while looking into the Debian tool, then please tell us.

The problem with uncommented mystery code like that is that it easily
looks pointless and is at risk of getting changed or removed, even if
there was a good reason for it (which I still suspect there wasn't
though).

</soapbox>

Cheers,
Ulf

2018-02-13 13:08:08

by Ulf Magnusson

[permalink] [raw]
Subject: Re: Linux 4.16-rc1: regression bisected, Debian kernel package tool make-kpkg stalls indefinitely during kernel build due to commit "kconfig: remove check_stdin()"

On Tue, Feb 13, 2018 at 1:35 PM, Ulf Magnusson <[email protected]> wrote:
> On Tue, Feb 13, 2018 at 12:33:24PM +0100, Ulf Magnusson wrote:
>> On Tue, Feb 13, 2018 at 11:00:49AM +0100, Sander Eikelenboom wrote:
>> > On 13/02/18 05:09, Masahiro Yamada wrote:
>> > > 2018-02-13 12:00 GMT+09:00 Woody Suwalski <[email protected]>:
>> > >> Sander Eikelenboom wrote:
>> > >>>
>> > >>> L.S.,
>> > >>>
>> > >>> The Debian kernel-package tool make-kpkg for easy building of upstream
>> > >>> kernels on Debian fails with linux 4.16-rc1.
>> > >>>
>> > >>> The tool (perl script) while invoked with:
>> > >>> make-kpkg --initrd --append_to_version -20180212 kernel_image
>> > >>>
>> > >>> On a git tree with a .config from the previous kernel release, so new
>> > >>> KConfig questions have to be asked on new or changed options.
>> > >>>
>> > >>> The script stalls indefinitely while it seems to be excuting:
>> > >>> exec make kpkg_version=13.018+nmu1 -f
>> > >>> /usr/share/kernel-package/ruleset/minimal.mk debian
>> > >>> APPEND_TO_VERSION=-t440s-20180212 INITRD=YES
>> > >>>
>> > >>> After using ctrl-c to break out it, i get:
>> > >>> ^CFailed to create a ./debian directory: No such file or directory at
>> > >>> /usr/bin/make-kpkg line 970.
>> > >>>
>> > >>> Bisection turned up as culprit:
>> > >>> commit d2a04648a5dbc3d1d043b35257364f0197d4d868
>> > >>> kconfig: remove check_stdin()
>> > >>> Except silentoldconfig, valid_stdin is 1, so check_stdin() is
>> > >>> no-op.
>> > >>> oldconfig and silentoldconfig work almost in the same way except
>> > >>> that
>> > >>> the latter generates additional files under include/. Both ask users
>> > >>> for input for new symbols.
>> > >>> I do not know why only silentoldconfig requires stdio be tty.
>> > >>> $ rm -f .config; touch .config
>> > >>> $ yes "" | make oldconfig > stdout
>> > >>> $ rm -f .config; touch .config
>> > >>> $ yes "" | make silentoldconfig > stdout
>> > >>> make[1]: *** [silentoldconfig] Error 1
>> > >>> make: *** [silentoldconfig] Error 2
>> > >>> $ tail -n 4 stdout
>> > >>> Console input/output is redirected. Run 'make oldconfig' to update
>> > >>> configuration.
>> > >>> scripts/kconfig/Makefile:40: recipe for target
>> > >>> 'silentoldconfig' failed
>> > >>> Makefile:507: recipe for target 'silentoldconfig' failed
>> > >>> Redirection is useful, for example, for testing where we want to
>> > >>> give
>> > >>> particular key inputs from a test file, then check the result.
>> > >>> Signed-off-by: Masahiro Yamada <[email protected]>
>> > >>> Reviewed-by: Ulf Magnusson <[email protected]>
>> > >>>
>> > >>> Reverting this specific commit makes make-kpkg work again as usual.
>> > >>>
>> > >>> Version of the kernel-package used:
>> > >>> ii kernel-package
>> > >>> 13.018+nmu1
>> > >>>
>> > >>>
>> > >>> I also cc'ed the Debian developer who maintains the kernel-package
>> > >>> package: Manoj Srivastava
>> > >>>
>> > >>> --
>> > >>> Sander
>> > >>>
>> > >> I have noticed today the same - the kernel-build blockage was in (as I
>> > >> recall)
>> > >> srcipts/kconfig/conf -s --silentoldconfig Kbuild
>> > >>
>> > >> I have bypassed it by regenerating the .config "by hand"...
>> > >
>> > >
>> > > silentoldconfig asks you values for new symbols.
>> > > So, you must answer questions to proceed.
>> >
>> > I know, but it stalls before asking the questions.
>> >
>> > >
>> > > How does 'make-kpkg' handle silentoldconfig?
>> > >
>> > > Re-direct stdio, then make it forcibly fail?
>> >
>> > I don't know, it is a bunch of perl and shell scripts that gets invoked, not the most easy to comprehend if you are not familiar with them. I'm just a user of the tool.
>> >
>> > So i would have to defer that question to the Debian package maintainer, hopefully he will chime in.
>> >
>> > --
>> > Sander
>> >
>> > >
>> > >
>> > >
>> >
>>
>> Hello,
>>
>> What the commit does is to make silentoldconfig not immediately exit(1)
>> when both of the following apply:
>>
>> 1. stdin is from something that's not a terminal
>>
>> 2. New symbols are prompted for
>>
>> All the outputs (.config and the include/generated/ and include/config/
>> trees) are generated after the point where silentoldconfig would
>> previously exit(1), afaics, so the effects of the commit can be
>> summarized as follows:
>>
>> * If no new symbols appear (that would be prompted for), the
>> behavior is exactly the same as before.
>>
>> (check_stdin() never seems to get called unless a value would
>> actually be prompted for, which makes sense.)
>>
>> * If new symbols appear and stdin is a tty, the behavior is also
>> exactly the same as before.
>>
>> And finally, the only case where the behavior differs:
>>
>> * If new symbols appear and stdin is not a tty, the
>> new behavior is to prompt (to expect e.g. "n"/"m"/"y" from
>> wherever stdin is coming from).
>>
>> The old behavior was to exit(1) without generating any output
>> files.
>>
>> Hopefully that clarifies it.
>>
>> The intent of the commit was just to clean up the code a bit, since
>> there doesn't seem to be a good reason to bail just because stdin
>> happens to not be a tty (plus it's inconsistent with the way oldconfig
>> works, which never bailed).
>>
>> silentoldconfig is something of an internal implementation detail at
>> this point by the way. It's basically oldconfig + generate the
>> configuration stuff in include/generated/ and include/config/ that
>> actually gets used during the build. Normally it's called automatically
>> as needed when building the kernel.
>>
>> See https://www.spinics.net/lists/kernel/msg2720574.html for some more
>> details re. silentoldconfig.
>>
>> Cheers,
>> Ulf
>
> By the way: If you can figure out a reason for why that stdin check was
> there before while looking into the Debian tool, then please tell us.
>
> The problem with uncommented mystery code like that is that it easily
> looks pointless and is at risk of getting changed or removed, even if
> there was a good reason for it (which I still suspect there wasn't
> though).
>
> </soapbox>
>
> Cheers,
> Ulf

Shouldn't be a problem to back this one out either if it turns out to
cause massive amounts of pain in practice I guess, even if it's the
Debian tools doing something weird.

Good to look into what it is they're doing in any case.

Cheers,
Ulf

Subject: Re: Linux 4.16-rc1: regression bisected, Debian kernel package tool make-kpkg stalls indefinitely during kernel build due to commit "kconfig: remove check_stdin()"

JFYI: This issues is tracked in the regression reports for Linux 4.16
(http://bit.ly/lnxregrep416 ) with this id:

Linux-Regression-ID: lr#2fd778

Please include this line in the comment section of patches that are
supposed to fix the issue. Please also mention the string once in other
mailinglist threads or different bug tracking entries if you or someone
else start to discuss the issue there. By including that string you make
it a whole lot easier to track where an issue gets discussed and how far
patches to fix it have made it. For more details on this please see
here: http://bit.ly/lnxregtrackid

Thx for your help. Ciao, Thorsten

On 12.02.2018 20:01, Sander Eikelenboom wrote:
> L.S.,
>
> The Debian kernel-package tool make-kpkg for easy building of upstream kernels on Debian fails with linux 4.16-rc1.
>
> The tool (perl script) while invoked with:
> make-kpkg --initrd --append_to_version -20180212 kernel_image
>
> On a git tree with a .config from the previous kernel release, so new KConfig questions have to be asked on new or changed options.
>
> The script stalls indefinitely while it seems to be excuting:
> exec make kpkg_version=13.018+nmu1 -f /usr/share/kernel-package/ruleset/minimal.mk debian APPEND_TO_VERSION=-t440s-20180212 INITRD=YES
>
> After using ctrl-c to break out it, i get:
> ^CFailed to create a ./debian directory: No such file or directory at /usr/bin/make-kpkg line 970.
>
>
> Bisection turned up as culprit:
> commit d2a04648a5dbc3d1d043b35257364f0197d4d868
> kconfig: remove check_stdin()
>
> Except silentoldconfig, valid_stdin is 1, so check_stdin() is no-op.
>
> oldconfig and silentoldconfig work almost in the same way except that
> the latter generates additional files under include/. Both ask users
> for input for new symbols.
>
> I do not know why only silentoldconfig requires stdio be tty.
>
> $ rm -f .config; touch .config
> $ yes "" | make oldconfig > stdout
> $ rm -f .config; touch .config
> $ yes "" | make silentoldconfig > stdout
> make[1]: *** [silentoldconfig] Error 1
> make: *** [silentoldconfig] Error 2
> $ tail -n 4 stdout
> Console input/output is redirected. Run 'make oldconfig' to update configuration.
>
> scripts/kconfig/Makefile:40: recipe for target 'silentoldconfig' failed
> Makefile:507: recipe for target 'silentoldconfig' failed
>
> Redirection is useful, for example, for testing where we want to give
> particular key inputs from a test file, then check the result.
>
> Signed-off-by: Masahiro Yamada <[email protected]>
> Reviewed-by: Ulf Magnusson <[email protected]>
>
> Reverting this specific commit makes make-kpkg work again as usual.
>
> Version of the kernel-package used:
> ii kernel-package 13.018+nmu1
>
>
> I also cc'ed the Debian developer who maintains the kernel-package package: Manoj Srivastava
>
> --
> Sander
>
>
> http://news.gmane.org/find-root.php?message_id=b7f71558-0e57-cacb-280c-a9d3baa030b2%40eikelenboom.it
> http://mid.gmane.org/b7f71558-0e57-cacb-280c-a9d3baa030b2%40eikelenboom.it
>

2018-03-18 13:18:04

by Sander Eikelenboom

[permalink] [raw]
Subject: Re: Linux 4.16-rc1: regression bisected, Debian kernel package tool make-kpkg stalls indefinitely during kernel build due to commit "kconfig: remove check_stdin()"

On 13/02/18 14:07, Ulf Magnusson wrote:
> On Tue, Feb 13, 2018 at 1:35 PM, Ulf Magnusson <[email protected]> wrote:
>> On Tue, Feb 13, 2018 at 12:33:24PM +0100, Ulf Magnusson wrote:
>>> On Tue, Feb 13, 2018 at 11:00:49AM +0100, Sander Eikelenboom wrote:
>>>> On 13/02/18 05:09, Masahiro Yamada wrote:
>>>>> 2018-02-13 12:00 GMT+09:00 Woody Suwalski <[email protected]>:
>>>>>> Sander Eikelenboom wrote:
>>>>>>>
>>>>>>> L.S.,
>>>>>>>
>>>>>>> The Debian kernel-package tool make-kpkg for easy building of upstream
>>>>>>> kernels on Debian fails with linux 4.16-rc1.
>>>>>>>
>>>>>>> The tool (perl script) while invoked with:
>>>>>>> make-kpkg --initrd --append_to_version -20180212 kernel_image
>>>>>>>
>>>>>>> On a git tree with a .config from the previous kernel release, so new
>>>>>>> KConfig questions have to be asked on new or changed options.
>>>>>>>
>>>>>>> The script stalls indefinitely while it seems to be excuting:
>>>>>>> exec make kpkg_version=13.018+nmu1 -f
>>>>>>> /usr/share/kernel-package/ruleset/minimal.mk debian
>>>>>>> APPEND_TO_VERSION=-t440s-20180212 INITRD=YES
>>>>>>>
>>>>>>> After using ctrl-c to break out it, i get:
>>>>>>> ^CFailed to create a ./debian directory: No such file or directory at
>>>>>>> /usr/bin/make-kpkg line 970.
>>>>>>>
>>>>>>> Bisection turned up as culprit:
>>>>>>> commit d2a04648a5dbc3d1d043b35257364f0197d4d868
>>>>>>> kconfig: remove check_stdin()
>>>>>>> Except silentoldconfig, valid_stdin is 1, so check_stdin() is
>>>>>>> no-op.
>>>>>>> oldconfig and silentoldconfig work almost in the same way except
>>>>>>> that
>>>>>>> the latter generates additional files under include/. Both ask users
>>>>>>> for input for new symbols.
>>>>>>> I do not know why only silentoldconfig requires stdio be tty.
>>>>>>> $ rm -f .config; touch .config
>>>>>>> $ yes "" | make oldconfig > stdout
>>>>>>> $ rm -f .config; touch .config
>>>>>>> $ yes "" | make silentoldconfig > stdout
>>>>>>> make[1]: *** [silentoldconfig] Error 1
>>>>>>> make: *** [silentoldconfig] Error 2
>>>>>>> $ tail -n 4 stdout
>>>>>>> Console input/output is redirected. Run 'make oldconfig' to update
>>>>>>> configuration.
>>>>>>> scripts/kconfig/Makefile:40: recipe for target
>>>>>>> 'silentoldconfig' failed
>>>>>>> Makefile:507: recipe for target 'silentoldconfig' failed
>>>>>>> Redirection is useful, for example, for testing where we want to
>>>>>>> give
>>>>>>> particular key inputs from a test file, then check the result.
>>>>>>> Signed-off-by: Masahiro Yamada <[email protected]>
>>>>>>> Reviewed-by: Ulf Magnusson <[email protected]>
>>>>>>>
>>>>>>> Reverting this specific commit makes make-kpkg work again as usual.
>>>>>>>
>>>>>>> Version of the kernel-package used:
>>>>>>> ii kernel-package
>>>>>>> 13.018+nmu1
>>>>>>>
>>>>>>>
>>>>>>> I also cc'ed the Debian developer who maintains the kernel-package
>>>>>>> package: Manoj Srivastava
>>>>>>>
>>>>>>> --
>>>>>>> Sander
>>>>>>>
>>>>>> I have noticed today the same - the kernel-build blockage was in (as I
>>>>>> recall)
>>>>>> srcipts/kconfig/conf -s --silentoldconfig Kbuild
>>>>>>
>>>>>> I have bypassed it by regenerating the .config "by hand"...
>>>>>
>>>>>
>>>>> silentoldconfig asks you values for new symbols.
>>>>> So, you must answer questions to proceed.
>>>>
>>>> I know, but it stalls before asking the questions.
>>>>
>>>>>
>>>>> How does 'make-kpkg' handle silentoldconfig?
>>>>>
>>>>> Re-direct stdio, then make it forcibly fail?
>>>>
>>>> I don't know, it is a bunch of perl and shell scripts that gets invoked, not the most easy to comprehend if you are not familiar with them. I'm just a user of the tool.
>>>>
>>>> So i would have to defer that question to the Debian package maintainer, hopefully he will chime in.
>>>>
>>>> --
>>>> Sander
>>>>
>>>>>
>>>>>
>>>>>
>>>>
>>>
>>> Hello,
>>>
>>> What the commit does is to make silentoldconfig not immediately exit(1)
>>> when both of the following apply:
>>>
>>> 1. stdin is from something that's not a terminal
>>>
>>> 2. New symbols are prompted for
>>>
>>> All the outputs (.config and the include/generated/ and include/config/
>>> trees) are generated after the point where silentoldconfig would
>>> previously exit(1), afaics, so the effects of the commit can be
>>> summarized as follows:
>>>
>>> * If no new symbols appear (that would be prompted for), the
>>> behavior is exactly the same as before.
>>>
>>> (check_stdin() never seems to get called unless a value would
>>> actually be prompted for, which makes sense.)
>>>
>>> * If new symbols appear and stdin is a tty, the behavior is also
>>> exactly the same as before.
>>>
>>> And finally, the only case where the behavior differs:
>>>
>>> * If new symbols appear and stdin is not a tty, the
>>> new behavior is to prompt (to expect e.g. "n"/"m"/"y" from
>>> wherever stdin is coming from).
>>>
>>> The old behavior was to exit(1) without generating any output
>>> files.
>>>
>>> Hopefully that clarifies it.
>>>
>>> The intent of the commit was just to clean up the code a bit, since
>>> there doesn't seem to be a good reason to bail just because stdin
>>> happens to not be a tty (plus it's inconsistent with the way oldconfig
>>> works, which never bailed).
>>>
>>> silentoldconfig is something of an internal implementation detail at
>>> this point by the way. It's basically oldconfig + generate the
>>> configuration stuff in include/generated/ and include/config/ that
>>> actually gets used during the build. Normally it's called automatically
>>> as needed when building the kernel.
>>>
>>> See https://www.spinics.net/lists/kernel/msg2720574.html for some more
>>> details re. silentoldconfig.
>>>
>>> Cheers,
>>> Ulf
>>
>> By the way: If you can figure out a reason for why that stdin check was
>> there before while looking into the Debian tool, then please tell us.
>>
>> The problem with uncommented mystery code like that is that it easily
>> looks pointless and is at risk of getting changed or removed, even if
>> there was a good reason for it (which I still suspect there wasn't
>> though).
>>
>> </soapbox>
>>
>> Cheers,
>> Ulf
>
> Shouldn't be a problem to back this one out either if it turns out to
> cause massive amounts of pain in practice I guess, even if it's the
> Debian tools doing something weird.
>
> Good to look into what it is they're doing in any case.
>
> Cheers,
> Ulf
>

Hi Ulf / Masahiro,

Unfortunately the Debian maintainer hasn't responded to this thread, nor on
the Debian bugtracker (https://bugs.debian.org/cgi-bin/bugreport.cgi?bug=890817)
issue i made.

--
Sander









Linux-Regression-ID: lr#2fd778



2018-05-17 05:10:18

by Kevin Locke

[permalink] [raw]
Subject: Re: Linux 4.16-rc1: regression bisected, Debian kernel package tool make-kpkg stalls indefinitely during kernel build due to commit "kconfig: remove check_stdin()"

On Tue, Feb 13, 2018 at 2:07 PM, Ulf Magnusson <[email protected]> wrote:
>> On Tue, Feb 13, 2018 at 12:33:24PM +0100, Ulf Magnusson wrote:
>>>>>> Sander Eikelenboom wrote:
>>>>>>> The Debian kernel-package tool make-kpkg for easy building of upstream
>>>>>>> kernels on Debian fails with linux 4.16-rc1.
>>>>>>>
>>>>>>> Bisection turned up as culprit:
>>>>>>> commit d2a04648a5dbc3d1d043b35257364f0197d4d868
>>>
>>> What the commit does is to make silentoldconfig not immediately exit(1)
>>> when both of the following apply:
>>>
>>> 1. stdin is from something that's not a terminal
>>>
>>> 2. New symbols are prompted for
>
> Shouldn't be a problem to back this one out either if it turns out to
> cause massive amounts of pain in practice I guess, even if it's the
> Debian tools doing something weird.
>
> Good to look into what it is they're doing in any case.

It appears that make-kpkg is trying to extract kernel version and
configuration information by including the kernel Makefile then
referencing the variables it exports. The offending make-kpkg
Makefile is kernel_version.mk[1] which can be simplified to the
following example:

-8<- make-kpkg-regression.mk -----------------------------------------
include Makefile
.PHONY: debian_VERSION
debian_VERSION:
-8<-------------------------------------------------------------------

Invoking this script from the root of the kernel source tree, with
stderr redirected (but not stdin) demonstrates the issue:

make -f make-kpkg-regression.mk debian_VERSION >/dev/null 2>&1

Before d2a04648a5db this would exit, after it will hang waiting for
input. This occurs because the debian_VERSION target name isn't in
no-dot-config-targets defined in Makefile, so Makefile invokes
silentoldconfig automatically as necessary.[2]

I think the issue is best fixed by make-kpkg, and that d2a04648a5db
doesn't need to be reverted. The simple fix would be for make-kpkg to
redirect stdin when redirecting stdout/stderr so that
scripts/kconfig/conf will fail as it did before. The better fix would
be for make-kpkg to use a supported interface for getting the
variables it needs, rather than including Makefile.

Best,
Kevin

1. https://salsa.debian.org/srivasta/kernel-package/blob/master/kernel/ruleset/kernel_version.mk
2. Interestingly, it's not just that the target isn't in
no-dot-config-targets. make-kpkg actually sets `dot-config := 1`
to force silentoldconfig (since 38399c1[3]).
3. https://salsa.debian.org/srivasta/kernel-package/commit/38399c1