[patch] e1000=y && e1000e=m regression fix (was: Re: [regression] e1000e broke e1000)

[Ingo Molnar <mingo@elte.hu>]

* Jeff Garzik <jeff@garzik.org> wrote:

>> We've got three thousand Kconfig options - it is clearly not 
>> realistic for users to keep such details in mind to avoid pitfalls.
>
> Agreed -- hence the multiple announcements, including in this thread, 
> to put said details into mind.

which part of "it took a kernel developer more than an hour to figure 
out why his laptop had a dead network interface" did you not understand? 
Whatever you did, it was not apparent to me. I dont follow every tiny 
detail of the e1000 driver family, nor do 99%+ [*] of our users.

find the fix below, against current -git.

the current upstream behavior is the worst possible one and is just a 
plain bug, and the solution is dead-simple.

	Ingo

[*] guesstimate

--------------->
Subject: e1000=y && e1000e=m regression fix
From: Ingo Molnar <mingo@elte.hu>
Date: Wed Apr 09 21:09:35 CEST 2008

fix a regression from v2.6.24: do not transfer the e1000e PCI IDs from 
e1000 to e1000e if e1000 is built-in and e1000e is a module.

Built-in drivers take precedence over modules in many ways - and in this 
case it's clear that the user intended the e1000 driver to be the 
primary one. "Silently change behavior and break existing configs" is 
never a good migration strategy. Most users will use distro kernels that 
are not affected by this problem at all - nor are they affected by this 
patch - but this problem can hit users and developers who build their 
kernels themselves and migrate from v2.6.24 to v2.6.25.

this fixes: http://bugzilla.kernel.org/show_bug.cgi?id=10427

Signed-off-by: Ingo Molnar <mingo@elte.hu>
---
 drivers/net/Kconfig |    2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

Index: linux-x86.q/drivers/net/Kconfig
===================================================================
--- linux-x86.q.orig/drivers/net/Kconfig
+++ linux-x86.q/drivers/net/Kconfig
@@ -2022,7 +2022,7 @@ config E1000E
 	  will be called e1000e.
 
 config E1000E_ENABLED
-	def_bool E1000E != n
+	def_bool E1000E = y || ((E1000E != n) && (E1000 = E1000E))
 
 config IP1000
 	tristate "IP1000 Gigabit Ethernet support"