powercap/RAPL: prevent overridding bits outside of the mask

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 <adam.lessnau@intel.com>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>

diff --git a/drivers/powercap/intel_rapl.c b/drivers/powercap/intel_rapl.c
index 9ddad0815ba909a7c77de8f93db06e7bc712d246..d1694f1def7278d17249bbbc23e0a64b3704ba5d 100644 (file)
--- a/drivers/powercap/intel_rapl.c
+++ b/drivers/powercap/intel_rapl.c
@@ -874,7 +874,9 @@ 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];