| From | Sasha Levin <> | Subject | [PATCH AUTOSEL for 4.9 151/293] powercap/RAPL: prevent overridding bits outside of the mask | Date | Mon, 9 Apr 2018 00:24:51 +0000 |
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From: Adam Lessnau <adam.lessnau@intel.com>
[ Upstream commit edbdabc62328ec0ac98d83ca384bf9fd5251ade6 ]
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> Signed-off-by: Sasha Levin <alexander.levin@microsoft.com> --- 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]; -- 2.15.1
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