Re: RFC: changes to microcode update driver.

[Mikael Pettersson <mikpe@csd.uu.se>]

Tigran Aivazian writes:
 > The patch was almost ready (together with Intel's changes) but I 
 > discovered that microcode module (or in fact ANY module that is loaded 
 > first on my system, 2.6.0-test6) is not unloadable, i.e. usage count stays 
 > at 1 even though nothing is using it. I am not aware of this general 

Maybe unrelated, but 2.6.0-test6 has a bug in drivers/char/misc.c's
module autoloading code, which causes device open() failures, and
subsequent unloading failures due to the usage count being 1 too high.

I posted the fix below, and Linus included it in a recent -bk snapshot.

/Mikael

diff -ruN linux-2.6.0-test6/drivers/char/misc.c linux-2.6.0-test6.char-misc-fix/drivers/char/misc.c
--- linux-2.6.0-test6/drivers/char/misc.c	2003-09-28 12:19:40.000000000 +0200
+++ linux-2.6.0-test6.char-misc-fix/drivers/char/misc.c	2003-10-04 14:55:45.000000000 +0200
@@ -157,12 +157,11 @@
 		list_for_each_entry(c, &misc_list, list) {
 			if (c->minor == minor) {
 				new_fops = fops_get(c->fops);
-				if (!new_fops)
-					goto fail;
 				break;
 			}
 		}
-		goto fail;
+		if (!new_fops)
+			goto fail;
 	}
 
 	err = 0;