lkml.org 
[lkml]   [2023]   [Mar]   [29]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
 
Messages in this thread
/
From
Date
SubjectRe: [PATCH] cpufreq: Fix policy->freq_table is NULL in __cpufreq_driver_target()
On Wed, Mar 29, 2023 at 3:36 PM Yajun Deng <yajun.deng@linux.dev> wrote:
>
> __resolve_freq() may be return target_freq if policy->freq_table is
> NULL. In this case, it should return -EINVAL before __target_index().

Even so, __target_index() itself doesn't dereference freq_table
AFAICS, so arguably the driver should be prepared to deal with a NULL
freq_table which comes from it after all.

Or, if you want to argue that drivers providing ->target_index() must
also provide freq_table that is not NULL, a check to that effect needs
to be done at the driver registration time IMO.

> Signed-off-by: Yajun Deng <yajun.deng@linux.dev>
> ---
> drivers/cpufreq/cpufreq.c | 2 +-
> 1 file changed, 1 insertion(+), 1 deletion(-)
>
> diff --git a/drivers/cpufreq/cpufreq.c b/drivers/cpufreq/cpufreq.c
> index c0e5be0fe2d6..308a3df1a940 100644
> --- a/drivers/cpufreq/cpufreq.c
> +++ b/drivers/cpufreq/cpufreq.c
> @@ -2299,7 +2299,7 @@ int __cpufreq_driver_target(struct cpufreq_policy *policy,
> return cpufreq_driver->target(policy, target_freq, relation);
> }
>
> - if (!cpufreq_driver->target_index)
> + if (!cpufreq_driver->target_index || !policy->freq_table)
> return -EINVAL;
>
> return __target_index(policy, policy->cached_resolved_idx);
> --

\
 
 \ /
  Last update: 2023-03-29 16:31    [W:0.125 / U:0.032 seconds]
©2003-2020 Jasper Spaans|hosted at Digital Ocean and TransIP|Read the blog|Advertise on this site