From mboxrd@z Thu Jan 1 00:00:00 1970 From: rosslagerwall@gmail.com Subject: Re: [stable request <=3.7] acpi-cpufreq: set current frequency based on target P-State Date: Tue, 25 Mar 2014 22:18:03 +0000 Message-ID: <20140325221803.GA32518@hobo.lan> References: <20131220081912.GA13684@hobo.Home> <1395785057-28903-1-git-send-email-vlee@twopensource.com> Mime-Version: 1.0 Content-Type: text/plain; charset=utf-8 Return-path: Content-Disposition: inline In-Reply-To: <1395785057-28903-1-git-send-email-vlee@twopensource.com> Sender: stable-owner@vger.kernel.org To: Vinson Lee Cc: stable@vger.kernel.org, "Rafael J. Wysocki" , Viresh Kumar , cpufreq@vger.kernel.org, linux-pm@vger.kernel.org, Len Brown , "Rafael J. Wysocki" List-Id: linux-pm@vger.kernel.org On Tue, Mar 25, 2014 at 03:04:16PM -0700, Vinson Lee wrote: > Hi. > > Please backport upstream commit 8673b83bf2f013379453b4779047bf3c6ae387e4 > "acpi-cpufreq: set current frequency based on target P-State" to stable > kernels 3.7 and earlier. This patch enables the kernel to control > P-states on several platforms. Without this patch, the kernel was unable > to control P-states on the same platforms. > > The upstream patch cleanly applies to 3.7. > > A backported patch is needed with the removal of SYSTEM_AMD_MSR_CAPABLE > for kernels 3.6 and earlier. > I seem to recall that the problem was a regression introduced by commit 5a1c0228 (cpufreq: Avoid calling cpufreq driver's target() routine if target_freq == policy->cur) which was introduced in the 3.8 cycle. Are you sure it is necessary for kernels < 3.8? Regards -- Ross Lagerwall