Check if delta_us is not zero and return -EINVAL if it is. delta_us is unlikely to be zero as there is a sleep between the reads of the two timestamps. This is to fix the following warning when compiling the QAT driver using clang scan-build: drivers/crypto/intel/qat/qat_common/adf_clock.c:87:9: warning: Division by zero [core.DivideZero] 87 | temp = DIV_ROUND_CLOSEST_ULL(temp, delta_us); | ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ Fixes: e2980ba57e79 ("crypto: qat - add measure clock frequency") Signed-off-by: Adam Guerin <adam.guerin@xxxxxxxxx> Reviewed-by: Giovanni Cabiddu <giovanni.cabiddu@xxxxxxxxx> --- drivers/crypto/intel/qat/qat_common/adf_clock.c | 3 +++ 1 file changed, 3 insertions(+) diff --git a/drivers/crypto/intel/qat/qat_common/adf_clock.c b/drivers/crypto/intel/qat/qat_common/adf_clock.c index 01e0a389e462..cf89f57de2a7 100644 --- a/drivers/crypto/intel/qat/qat_common/adf_clock.c +++ b/drivers/crypto/intel/qat/qat_common/adf_clock.c @@ -83,6 +83,9 @@ static int measure_clock(struct adf_accel_dev *accel_dev, u32 *frequency) } delta_us = timespec_to_us(&ts3) - timespec_to_us(&ts1); + if (!delta_us) + return -EINVAL; + temp = (timestamp2 - timestamp1) * ME_CLK_DIVIDER * 10; temp = DIV_ROUND_CLOSEST_ULL(temp, delta_us); /* -- 2.40.1