On Wed, 17 Feb 2010, Matthew Garrett wrote: > On Wed, Feb 17, 2010 at 01:24:58PM -0500, Len Brown wrote: > > On Wed, 17 Feb 2010, Matthew Garrett wrote: > > > We seem to have no good history of where these blacklist entries came > > > from, and we know that at least one of them is actively harmful. Perhaps > > > replace them with a debug statement on affected machines telling people > > > what they need to pass to restore the blacklist behaviour, and to let us > > > know if it's necessary? > > > > Actually, it wasn't actively harmful until we broke "acpi=ht". > > Indeed, it was actively helpful in pointing out that regression:-) > > The machines in question are falling back to apm, so probably losing > some level of powersaving support. I'd say that's harmful :) Well, on ThinkPads you probably want APM on the older models, for better power savings and less surprise when trying to suspend to RAM or to disk. > > The other entries in today's acpi_dmi_table[] are less clear > > and should probably be modified only with some care... > > At least one of them covers a single submodel in a range, despite them > all running the same BIOS. I'd really lean towards them being bogus at > this stage of the game. On that, we do agree. That ThinkPad entry is completely bogus, I vote that we remove it if we're not going to fix it to apply to every ThinkPad with that BIOS. OTOH, every mention of the A22 I find in the network is coupled with "acpi=off", which matches what I know about the ThinkPads before the A31p, X31 and R40e/T40: they tend to work a lot better in APM mode. There are reports of some bizarre stuff, such as A22m laptops powering up by themselves some time after shutdown if ACPI is used, etc. I would suggest an ACPI cut-off date of 2005 (disable ACPI on anything older than 2005) for IBM ThinkPads, but this is going to shut down ACPI from people that never updated their firmware on some models that might be able to do ACPI properly. -- "One disk to rule them all, One disk to find them. One disk to bring them all and in the darkness grind them. In the Land of Redmond where the shadows lie." -- The Silicon Valley Tarot Henrique Holschuh -- 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
