Re: linux-next: build warnings after merge of the tomoyo tree

[Tetsuo Handa]

On 2022/05/31 9:44, Stephen Rothwell wrote:
> Hi all,
> 
> After merging the tomoyo tree, today's linux-next build (powerpc
> ppc64_defconfig) produced these warnings:
> 
> drivers/scsi/mpt3sas/mpt3sas_scsih.c:12412:9: note: '#pragma message: Please avoid flushing system-wide workqueues.'

This is neither "warning:" nor "error:". This is a "note:" message which also appears with "make W=1" case.

> Also, my x86_64 allmodconfig build gained these:

Yes, currently there are many matches when building all modules.
But do developers build all modules?

> Linus will not be happy ...

Hmm, an important part which was missing in commit 771c035372a036f8 ("deprecate
the '__deprecated' attribute warnings entirely and for good") is that Linus
builds all modules and reads all messages during the build?

If that is the case, reporting "Please avoid flushing system-wide workqueues."
every time sounds noisy for him.

But since __deprecated became no-op in v4.19, I guess that developers abandoned
efforts for removing __deprecated usage.

  v5.18: 13 references
  v5.10: 12 references
  v4.19: 12 references
  v4.18: 20 references
  v4.10: 25 references
  v4.0:  25 references
  v3.10: 37 references

What I'm trying to do is to teach developers about possibility of problems
at compile time. __deprecated suits here but is no-op.

Something like console_loglevel which can be controlled on per directory
basis (so that developers can deeply listen to messages from only modules
they maintain) is needed for kernel build?