Re: why does x86 "make defconfig" build a single, lonely module?

["Satyam Sharma" <satyam.sharma@gmail.com>]

Hi,

On 5/13/07, James Bottomley <James.Bottomley@steeleye.com> wrote:
> On Sun, 2007-05-13 at 11:10 -0500, James Bottomley wrote:
> > > -   depends on SCSI
> > > +   depends on SCSI_SCAN_ASYNC

This is incorrect, alright, but not because of any of the reasons James
mentions below.

The only reason why some module (or Kconfig option) should _depend_
on some other Kconfig option is if (*and only if*) it re-uses _code_
exported by said dependency.

In this particular case, SCSI_SCAN_ASYNC=y/n only controls the
default value of some variable somewhere in SCSI, so no other code
can meaningfully "depend" on it.

> > No.  SCSI_SCAN_ASYNC is a bool ... if you depend on it, you'll force the
> > wait scan to be built in, which isn't the idea at all.

Umm, this isn't true, actually.

> Plus SCSI_SCAN_ASYNC only sets the *default* for async scanning.  You
> can alter this at boot time, so you could need the wait scan module even
> with it set to N.

I think the _correct_ way to handle this situation (and which would make
everyone happy here; Robert can get his module-free builds with defconfig,
James gets his SCSI_WAIT_SCAN module even if nobody asked for it
explicitly) would be as follows:

---

Clean up Kconfig entry for CONFIG_SCSI_WAIT_SCAN.

Signed-off-by: Satyam Sharma <satyam.sharma@gmail.com>

---

 drivers/scsi/Kconfig |    5 ++---
 1 file changed, 2 insertions(+), 3 deletions(-)

---

diff -ruNp a/drivers/scsi/Kconfig b/drivers/scsi/Kconfig
--- a/drivers/scsi/Kconfig	2007-05-10 23:19:32.000000000 +0530
+++ b/drivers/scsi/Kconfig	2007-05-14 15:12:46.000000000 +0530
@@ -243,9 +243,8 @@ config SCSI_SCAN_ASYNC

 config SCSI_WAIT_SCAN
 	tristate
-	default m
-	depends on SCSI
-	depends on MODULES
+	default m if SCSI=m
+	default n

 menu "SCSI Transports"
 	depends on SCSI