From mboxrd@z Thu Jan 1 00:00:00 1970 From: Bjorn Helgaas Subject: Re: PROBLEM: CPU fan shuts down on load of fan.ko in kernel 2.6.18 and later Date: Wed, 3 Jan 2007 13:29:34 -0700 Message-ID: <200701031329.34665.bjorn.helgaas@hp.com> References: <1e2af89e0612280914n62a192e2kdb7e2677b55d2670@mail.gmail.com> <1e2af89e0612281536y769323a7l62c9df334d1e8a06@mail.gmail.com> <1e2af89e0701030340q7a01520cm831b6064af8f7881@mail.gmail.com> Mime-Version: 1.0 Content-Type: text/plain; charset="iso-8859-1" Content-Transfer-Encoding: 7bit Return-path: Received: from atlrel6.hp.com ([156.153.255.205]:47349 "EHLO atlrel6.hp.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S932075AbXACU3l (ORCPT ); Wed, 3 Jan 2007 15:29:41 -0500 In-Reply-To: <1e2af89e0701030340q7a01520cm831b6064af8f7881@mail.gmail.com> Content-Disposition: inline Sender: linux-acpi-owner@vger.kernel.org List-Id: linux-acpi@vger.kernel.org To: Matthew Brett Cc: linux-acpi@vger.kernel.org, konstantin.a.karasyov@intel.com On Wednesday 03 January 2007 04:40, Matthew Brett wrote: > > > > CPU fan shuts down on load of fan.ko in kernel 2.6.18 and later > > I am sorry to persist - but is there anything I can do further to help > debug this problem? Or somewhere else that I should ask? Thanks for your report and for persisting. This is exactly the right place to complain, but people might still be recovering from the holidays. There weren't many interesting changes in fan.c between 2.6.17 and 2.6.18. The problem you found is probably related to this: http://bugzilla.kernel.org/show_bug.cgi?id=5000 The patch in comment #24 looks like this for add and resume: result = acpi_bus_get_power(device->handle, &state); + if (state == ACPI_STATE_D0) + acpi_bus_set_power(fan->handle, ACPI_STATE_D3); + else if (state == ACPI_STATE_D3) + acpi_bus_set_power(fan->handle, ACPI_STATE_D0); + acpi_bus_set_power(fan->handle, state); whereas the code in 2.6.18 is this: result = acpi_bus_get_power(device->handle, &state); + device->flags.force_power_state = 1; + acpi_bus_set_power(device->handle, state); + device->flags.force_power_state = 0; It's interesting that the bugzilla patch inverts the fan power state while the 2.6.18 code does not. Konstantin can probably give you more useful help. I don't know the details of how the fan state is controlled. Bjorn