Comment 27 for bug 36158

I too have encounter the "system does not poweroff on shutdown" problem when I upgraded the kernel from 2.6.12-9 to 2.6.15-22.

Under kernel-2.6.12-9, there is a /proc/acpi directory, where as under kernel-2.6.15-22, /proc/acpi was missing. I read somewhere the acpi was to be moved to /sys, but i couldn't fine it there.

From the same cource, it suggest that acpi function for BIOS that is older then year 2000 is not supported. (http://justlinux.com/forum/archive/index.php/t-130279.html)

Then I recalled I saw a kernel configuration option for 2.6.15-22 under the ACPI section with the number 2000, the option is CONFIG_APCI_BLACKLIST_YEAR

When I check this CONFIG_ACPI_BLACKLIST_YEAR option in the config file for kernel-2.6.12-9, the option was set to 0.

The next clue to confirm the findings was from dmesg,

ACPI: BIOS age (1999) fails cutoff (2000), acpi=force is required to enable ACPI

So i added "acpi=force" to menu.lst, and rebooted, this soft the "no power off" problem for me.

Now the next question is, why is kernel-2.6.15-22 compiled with CONFIG_ACPI_BLACKLIST_YEAR=2000 where this was set to 0 in kernel-2.6.12-9?

Is this a policy by Ubuntu or from upstream Debian? What is the consquence if we reconfigure and recompile the kernel to set CONFIG_ACPI_BLACKLIST_YEAR=0 for kernel-2.6.15-22?

Also from #31993 Peter Whittaker suggected that "acpi=force" is not a work around for him because of the "S3 sleep" (whatever that is), will setting CONFIG_ACPI_BLACKLIST_YEAR=0 solve his problem too? Since kernel-2.6.12-9 works fine with that.