Re: [PATCH v2 04/24] linux-module: Do not use shell environment

[Jan Kiszka <jan.kiszka@siemens.com>]

On 23.11.21 13:24, Uladzimir Bely wrote:
> In the email from Friday, 19 Nov 2021. 15:44:12 +03 user Jan Kiszka wrote:
>> On 19.11.21 13:13, Uladzimir Bely wrote:
>>
>>> +KDIR := $(shell dpkg -L $(KERNEL_DEP) | grep "/lib/modules/.*/build")
>>> +endif
>>> +
>>> +# With sbuild `dh clean` is called before chroot's apt database updated.
>>> So, +# KDIR is empty at that moment and the override causes error. Will
>>> skip it. +ifneq ($(KDIR),)
>>>
>>>  override_dh_auto_clean:
>>>  	$(MAKE) -C $(KDIR) M=$(PWD) clean
>>>
>>> +endif
>>
>> This looks wrong, or at least fragile. Why can we live without a proper
>> clean on the kernel tree?
>>
>> Jan
> 
> Actually, this workaround with `ifneq ($(KDIR),)` I added to the patch after 
> the commit https://github.com/ilbers/isar/commit/248436880eb2 was applied to 
> `next`.
> 
> This change doesn't cancel a proper clean on the kernel. Here are some example 
> logs:
> 
> `next`: https://gist.github.com/WiseLord/0fb98bc036532ec03e4f763b2ba06a41
> `sbuild`: https://gist.github.com/WiseLord/3c35d477efc025bcc9cd3c5cbd3dbc5d
> 
> On current `next` code dh_clean (and override-related `make ... clean` on 
> kernel code) is executed by dpkg-buildpackage. At this point KDIR is set to a 
> proper value, so it works as expected.
> 
> With sbuild dh_clean happens to be executed twice:
> - 1: immediately after sbuild is run, executed by sbuild itself
> - 2: after few stages (like downloading deps and so on), executed by dpkg-
> buildpackage.
> 
> The issue is that at 1st execution KDIR is not set, so `make ... clean` 
> (coming with override) produces wrong command.
> 
> That's why this workaround (skip `make ... clean` in case of empty KDIR) was 
> added. Proper cleaning is still performed, but on the second call of dh_clean.
> 
> Probably, there is a way to say sbuild not to run this 'generic' dh_clean and 
> use just one from dpkg-buildpackage later...
> 

Thanks for the explanation. How about clarifying that no clean is lost
in the commit message?

Jan

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