From mboxrd@z Thu Jan 1 00:00:00 1970 From: dirk.brandewie@gmail.com Subject: [PATCH 1/2] cpufreq/intel_pstate: Do not load on VM that do not report max P state. Date: Tue, 5 Mar 2013 14:15:26 -0800 Message-ID: <1362521727-20666-2-git-send-email-dirk.brandewie@gmail.com> References: <1362521727-20666-1-git-send-email-dirk.brandewie@gmail.com> Return-path: DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20120113; h=x-received:from:to:cc:subject:date:message-id:x-mailer:in-reply-to :references; bh=ZjdM6ZRLXlf7tfsAQFuzWlvJcKe2fXSFEV4xLrDDVcE=; b=LtFO3zaP6+kEtWSHH8qSF09XRH8d2ApzReulda1hnJ0WBO2eYJVnoFy+oFyNju8ipN WVCwzPAaWVWz2IWV1DtYkhtBUr5/dSTGns6DR2rrCG1qN1GsE+i/PlEIwZJsaREEVqg8 a6dwFhkCjduTdaMyI9Ou7FJRGu1XhzB3BSXv4NSPjuBPJk4d1dOoiicUe9zw4G91B7JS rw7/uB8pZbR8MYIQb9KvAVK6dUKs3aznYJgoA2hgvsT+TK6ycYnvHSNdphvs3qnfb4Mv gGqLsXikshYfk3Va+VAZ7nBXdTWtByo7tR1Rx3yJVzzbcXAQZCcUUlfpk1a0ToS+FLTQ 92kQ== In-Reply-To: <1362521727-20666-1-git-send-email-dirk.brandewie@gmail.com> Sender: linux-kernel-owner@vger.kernel.org List-ID: MIME-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit To: linux-kernel@vger.kernel.org, cpufreq@vger.kernel.org Cc: konrad.wilk@oracle.com, jwboyer@redhat.com, Dirk Brandewie , Dirk Brandewie From: Dirk Brandewie It seems some VMs support the P state MSRs but return zeros. Fail gracefully if we are running in this environment. https://bugzilla.redhat.com/show_bug.cgi?id=916833 Reported-by: jwboyer@redhat.com Signed-off-by: Dirk Brandewie --- drivers/cpufreq/intel_pstate.c | 3 +++ 1 files changed, 3 insertions(+), 0 deletions(-) diff --git a/drivers/cpufreq/intel_pstate.c b/drivers/cpufreq/intel_pstate.c index 096fde0..2bfd083 100644 --- a/drivers/cpufreq/intel_pstate.c +++ b/drivers/cpufreq/intel_pstate.c @@ -662,6 +662,9 @@ static int intel_pstate_set_policy(struct cpufreq_policy *policy) cpu = all_cpu_data[policy->cpu]; + if (!policy->cpuinfo.max_freq) + return -ENODEV; + intel_pstate_get_min_max(cpu, &min, &max); limits.min_perf_pct = (policy->min * 100) / policy->cpuinfo.max_freq; -- 1.7.7.6