Re: Possible bug in SCSI Kconfig

["Fabio Comolli" <fabio.comolli@gmail.com>]

Hi.

On Wed, Oct 22, 2008 at 8:35 PM, Stefan Richter
<stefanr@s5r6.in-berlin.de> wrote:
> (adding Cc: LSML and author)
>
> On 10/22/2008, Fabio Comolli wrote at LKML:
>> Hi.
>> In kernel 2.6.27.2 - drivers/scsi/Kconfig we have:
>>
>> config SCSI_WAIT_SCAN
>>         tristate
>>         default m
>>         depends on SCSI
>>         depends on MODULES
>>
>> The tristate field is empty. This has the effect that this option is
>> not visible in menuconfig and so it's always selected. The default is
>> "m" for all architectures and so this module is always compiled if
>> SCSI and MODULES are both enabled.
>>
>> I'm using a patch like this one:
>>
>>  config SCSI_WAIT_SCAN
>> -     tristate
>> +     tristate "Wait until all the async scans are complete"
>>       default m
>>       depends on SCSI
>>       depends on MODULES
>>
>> to get rid of that module.
>>
>> Of course, I have no idea if this is correct or the current behavior
>> is the expected one.
>>
>> Regards,
>> Fabio
>
> What's the correct behaviour is contentious.  There have been complaints
> that it shouldn't be built if it is not needed.  However, how it
> currently works is how those who added and merged that feature thought
> that it should be.
>
> Notes on your suggestion:
>
>  - If you make it a visible prompt, you should also add a help text.
>    No Kconfig prompts without good help text, please!
>
>  - The suggested prompt text doesn't describe the matter too well.
>    scsi_wait_scan rather is a module which userland can use to get
>    a signal for when scans (by some but not all transports) are done.
>    (The signal is the end of module initialization of the
>    scsi_wait_scan module.)  I.e. the kernel as a whole doesn't
>    necessarily wait, just this module does.
>

Well, I didn't mean to have the patch merged. My point was just to
understand if the Kconfig was correct.

> You could use the comment in drivers/scsi/scsi_wait_scan.c and the
> changelog of
> http://git.kernel.org/?p=linux/kernel/git/torvalds/linux-2.6.git;a=commit;h=3e082a910d217b2e7b186077ebf5a1126a68c62f
> as a basis for the Kconfig help text.  You could actually add a help
> text even to invisible prompts, just for documentation purposes.

Well, the first line of comment in that file reads "This is a simple
module to wait until all the async scans are complete." More or less
the text I added to the tristate.

> --
> Stefan Richter
> -=====-==--- =-=- =-==-
> http://arcgraph.de/sr/
>

Regards,
Fabio