On 12-02-18, 15:51, Shilpasri G Bhat wrote:
> This patch fixes the below Coverity warning:
>
> *** CID 182816: Memory - illegal accesses (NEGATIVE_RETURNS)
> /drivers/cpufreq/powernv-cpufreq.c: 1008 in powernv_fast_switch()
> 1002 unsigned int target_freq)
> 1003 {
> 1004 int index;
> 1005 struct powernv_smp_call_data freq_data;
> 1006
> 1007 index = cpufreq_table_find_index_dl(policy, target_freq);
> >>> CID 182816: Memory - illegal accesses (NEGATIVE_RETURNS)
> >>> Using variable "index" as an index to array "powernv_freqs".
> 1008 freq_data.pstate_id = powernv_freqs[index].driver_data;
> 1009 freq_data.gpstate_id = powernv_freqs[index].driver_data;
> 1010 set_pstate(&freq_data);
> 1011
> 1012 return powernv_freqs[index].frequency;
> 1013 }
>
> Signed-off-by: Shilpasri G Bhat <shilpa.b...@linux.vnet.ibm.com>
> ---
> drivers/cpufreq/powernv-cpufreq.c | 3 +++
> 1 file changed, 3 insertions(+)
>
> diff --git a/drivers/cpufreq/powernv-cpufreq.c
> b/drivers/cpufreq/powernv-cpufreq.c
> index 29cdec1..69edfe9 100644
> --- a/drivers/cpufreq/powernv-cpufreq.c
> +++ b/drivers/cpufreq/powernv-cpufreq.c
> @@ -1005,6 +1005,9 @@ static unsigned int powernv_fast_switch(struct
> cpufreq_policy *policy,
> struct powernv_smp_call_data freq_data;
>
> index = cpufreq_table_find_index_dl(policy, target_freq);
> + if (unlikely(index < 0))
> + index = get_nominal_index();
> +
AFAICT, you will get -1 here only if the freq table had no valid
frequencies (or the freq table is empty). Why would that happen ?
> freq_data.pstate_id = powernv_freqs[index].driver_data;
> freq_data.gpstate_id = powernv_freqs[index].driver_data;
> set_pstate(&freq_data);
> --
> 1.8.3.1
--
viresh
