Re: [PATCH] cpufreq: Fix policy->freq_table is NULL in __cpufreq_driver_target()

From: Viresh Kumar
Date: Wed Mar 29 2023 - 23:57:22 EST


On 30-03-23, 01:39, Yajun Deng wrote:
> March 29, 2023 10:21 PM, "Rafael J. Wysocki" <rafael@xxxxxxxxxx> wrote:
>
> > On Wed, Mar 29, 2023 at 3:36 PM Yajun Deng <yajun.deng@xxxxxxxxx> 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.
> >
>
> But there is a statement 'unsigned int newfreq = policy->freq_table[index].frequency;'
> in __target_index(), if driver doesn't provide freq_table, __target_index()
> will fault before the driver itself.

Driver must provide a freq table here.

--
viresh