RE: [patch] fix boot with acpi=off

["Lebedev, Vladimir P" <vladimir.p.lebedev@intel.com>]

> acpi=off used to be handled by acpi_bus_register_driver()
> for these drivers.

> But now acpi_lock_ac_dir() and acpi_lock_battery_dir()
> for procfs are inserted before that in the _init functions.
This is fragment from SBS patch. 
-----------------------------------------
 	ACPI_FUNCTION_TRACE("acpi_ac_init");
 
-	acpi_ac_dir = proc_mkdir(ACPI_AC_CLASS, acpi_root_dir);
+	acpi_ac_dir = acpi_lock_ac_dir();
 	if (!acpi_ac_dir)
 		return_VALUE(-ENODEV);
-	acpi_ac_dir->owner = THIS_MODULE;
 
 	result = acpi_bus_register_driver(&acpi_ac_driver);
 	if (result < 0) {
-		remove_proc_entry(ACPI_AC_CLASS, acpi_root_dir);
+		acpi_unlock_ac_dir(acpi_ac_dir);
 		return_VALUE(-ENODEV);
 	}
------------------------------------------
Order of proc_mkdir and acpi_bus_register_driver is the same as order of
acpi_lock_ac_dir. Could you explain what you meant?

>Vladimir,
>Any reason that the procfs stuff can't be after the
>acpi_bus_register_driver()
>calls?

If we move it after acpi_bus_register_driver(), calls to create files
inside battery/ac directories (called from acpi_bus_register_driver via
acpi_{battery,ac}_add()) will fail. 


>Under what conditions could these lock functions fail?
If there is no /proc/acpi directory in which to create ac/battery
directories.





-----Original Message-----
From: Brown, Len 
Sent: Monday, July 10, 2006 10:16 AM
To: Pavel Machek; kernel list; Andrew Morton; Lebedev, Vladimir P
Cc: linux-acpi@vger.kernel.org
Subject: RE: [patch] fix boot with acpi=off

[adding linux-acpi@vger.kernel.org to cc]

acpi=off used to be handled by acpi_bus_register_driver()
for these drivers.

But now acpi_lock_ac_dir() and acpi_lock_battery_dir()
for procfs are inserted before that in the _init functions.

This will be a problem for sbs.c also.

Vladimir,
Any reason that the procfs stuff can't be after the
acpi_bus_register_driver()
calls?  Under what conditions could these lock functions fail?

-Len


>-----Original Message-----
>From: Pavel Machek [mailto:pavel@ucw.cz] 
>Sent: Saturday, July 08, 2006 8:44 AM
>To: kernel list; Andrew Morton; Brown, Len
>Subject: [patch] fix boot with acpi=off
>
>With acpi=off and acpi_ac/battery compiled into kernel, acpi breaks
>boot. This fixes it.
>
>Signed-off-by: Pavel Machek <pavel@suse.cz>
>
>---
>commit 30b8ecda788b096fbd7088808f9af65c41c3a83d
>tree 3c28088018932f9ceb18bcf980507474d4a50c4e
>parent 05f70501240c6ad5f852f13c187ee55579ad7bb8
>author <pavel@amd.ucw.cz> Sat, 08 Jul 2006 14:43:13 +0200
>committer <pavel@amd.ucw.cz> Sat, 08 Jul 2006 14:43:13 +0200
>
> drivers/acpi/ac.c      |    2 ++
> drivers/acpi/battery.c |    3 +++
> 2 files changed, 5 insertions(+), 0 deletions(-)
>
>diff --git a/drivers/acpi/ac.c b/drivers/acpi/ac.c
>index 24ccf81..432b6b7 100644
>--- a/drivers/acpi/ac.c
>+++ b/drivers/acpi/ac.c
>@@ -285,6 +285,8 @@ static int __init acpi_ac_init(void)
> {
> 	int result;
> 
>+	if (acpi_disabled)
>+		return -ENODEV;
> 
> 	acpi_ac_dir = acpi_lock_ac_dir();
> 	if (!acpi_ac_dir)
>diff --git a/drivers/acpi/battery.c b/drivers/acpi/battery.c
>index 2ce9b35..5af1f64 100644
>--- a/drivers/acpi/battery.c
>+++ b/drivers/acpi/battery.c
>@@ -764,6 +764,9 @@ static int __init acpi_battery_init(void
> {
> 	int result;
> 
>+	if (acpi_disabled)
>+		return -ENODEV;
>+
> 	acpi_battery_dir = acpi_lock_battery_dir();
> 	if (!acpi_battery_dir)
> 		return -ENODEV;
>
>-- 
>(english) http://www.livejournal.com/~pavelmachek
>(cesky, pictures) 
>http://atrey.karlin.mff.cuni.cz/~pavel/picture/horses/blog.html
>
-
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@vger.kernel.org
More majordomo info at  http://vger.kernel.org/majordomo-info.html
Please read the FAQ at  http://www.tux.org/lkml/