From mboxrd@z Thu Jan 1 00:00:00 1970 From: Len Brown Subject: Re: [stable] [PATCH 1/2 2.6.37.stable] intel_idle: disable NHM/WSM HW C-state auto-demotion Date: Wed, 23 Mar 2011 22:53:22 -0400 (EDT) Message-ID: References: <20110323225420.GE27334@kroah.com> Mime-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Return-path: In-reply-to: <20110323225420.GE27334@kroah.com> List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Sender: linux-pm-bounces@lists.linux-foundation.org Errors-To: linux-pm-bounces@lists.linux-foundation.org To: Greg KH Cc: linux-pm@lists.linux-foundation.org, stable@kernel.org List-Id: linux-pm@vger.kernel.org On Wed, 23 Mar 2011, Greg KH wrote: > On Tue, Mar 22, 2011 at 10:24:43PM -0400, Len Brown wrote: > > From: Len Brown > > > > upstream 14796fca2bd22acc73dd0887248d003b0f441d08 > > > > Hardware C-state auto-demotion is a mechanism where the HW overrides > > the OS C-state request, instead demoting to a shallower state, > > which is less expensive, but saves less power. > > > > Modern Linux should generally get exactly the states it requests. > > In particular, when a CPU is taken off-line, it must not be demoted, else > > it can prevent the entire package from reaching deep C-states. > > > > https://bugzilla.kernel.org/show_bug.cgi?id=25252 > > > > Signed-off-by: Len Brown > > This patch doesn't apply to the .38-stable tree, and it also needs to go > there, right? Can you please send a version that I can apply? it is already present in 2.6.38, as is the next one. That is why the subject specified 2.6.37.stable. thanks, -Len