On Mon, 10 Jul 2006 14:37:53 -0400 "Brown, Len" <len.brown@xxxxxxxxx> wrote: > Dunno why acpi_lock_ac_dir() makes pavel's box fail w/ acpi=off. a) Because acpi_ac_init() forgot to check acpi_disabled, so acpi_ac_init() calls acpi_lock_ac_dir() even with acpi=off. b) Because acpi_lock_ac_dir() is doing down() on an uninitialised semaphore, which hangs. The fix to b) is in your tree now. The fix for a) is below. From: Pavel Machek <pavel@xxxxxx> With acpi=off and acpi_ac/battery compiled into kernel, acpi breaks boot. This fixes it. Signed-off-by: Pavel Machek <pavel@xxxxxxx> Cc: "Brown, Len" <len.brown@xxxxxxxxx> Signed-off-by: Andrew Morton <akpm@xxxxxxxx> --- drivers/acpi/ac.c | 2 ++ drivers/acpi/battery.c | 3 +++ 2 files changed, 5 insertions(+) diff -puN drivers/acpi/ac.c~acpi-fix-boot-with-acpi=off drivers/acpi/ac.c --- a/drivers/acpi/ac.c~acpi-fix-boot-with-acpi=off +++ a/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 -puN drivers/acpi/battery.c~acpi-fix-boot-with-acpi=off drivers/acpi/battery.c --- a/drivers/acpi/battery.c~acpi-fix-boot-with-acpi=off +++ a/drivers/acpi/battery.c @@ -757,6 +757,9 @@ 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; _ - To unsubscribe from this list: send the line "unsubscribe linux-acpi" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html