From mboxrd@z Thu Jan 1 00:00:00 1970 From: Adam Lessnau Subject: [PATCH] powercap/rapl: prevent overridding bits outside of the mask Date: Thu, 1 Jun 2017 11:21:50 +0200 Message-ID: <20170601092150.4474-1-adam.lessnau@intel.com> Return-path: Received: from mga07.intel.com ([134.134.136.100]:4034 "EHLO mga07.intel.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751589AbdFAJWN (ORCPT ); Thu, 1 Jun 2017 05:22:13 -0400 Sender: linux-pm-owner@vger.kernel.org List-Id: linux-pm@vger.kernel.org To: rjw@rjwysocki.net Cc: linux-pm@vger.kernel.org, Adam Lessnau Fixes wrong bits shift operation in the rapl_write_data_raw function, which might cause overridding bits outside of the mask. For example, writing new TIME_WINDOW1 value can override POWER_LIMIT1. Signed-off-by: Adam Lessnau --- drivers/powercap/intel_rapl.c | 4 +++- 1 file changed, 3 insertions(+), 1 deletion(-) diff --git a/drivers/powercap/intel_rapl.c b/drivers/powercap/intel_rapl.c index 3c71f608b444..6dc27afb8527 100644 --- a/drivers/powercap/intel_rapl.c +++ b/drivers/powercap/intel_rapl.c @@ -887,7 +887,9 @@ static int rapl_write_data_raw(struct rapl_domain *rd, cpu = rd->rp->lead_cpu; bits = rapl_unit_xlate(rd, rp->unit, value, 1); - bits |= bits << rp->shift; + bits <<= rp->shift; + bits &= rp->mask; + memset(&ma, 0, sizeof(ma)); ma.msr_no = rd->msrs[rp->id]; -- 2.13.0