Re: [PATCH V2] cpufreq: scmi: Avoid overflow of target_freq in fast switch

[Jagadeesh Kona]

On 5/28/2024 9:33 AM, Viresh Kumar wrote:
> On 27-05-24, 15:26, Jagadeesh Kona wrote:
> > On 5/20/2024 2:17 PM, Viresh Kumar wrote:
> > > On 20-05-24, 12:07, Jagadeesh Kona wrote:
> > > > Conversion of target_freq to HZ in scmi_cpufreq_fast_switch()
> > > > can lead to overflow if the multiplied result is greater than
> > > > UINT_MAX, since type of target_freq is unsigned int. Avoid this
> > > > overflow by assigning target_freq to unsigned long variable for
> > > > converting it to HZ.
> > > >
> > > > Signed-off-by: Jagadeesh Kona <quic_jkona@xxxxxxxxxxx>
> > > > ---
> > > > Changes in V2:
> > > >     - Updated freq variable from u64 to unsigned long to keep it
> > > >       consistent with the rate parameter in scmi .freq_set() callback
> > > >     - Link to v1: https://lore.kernel.org/all/20240517070157.19553-1-quic_jkona@xxxxxxxxxxx/
> > > > ---
> > > >    drivers/cpufreq/scmi-cpufreq.c | 4 ++--
> > > >    1 file changed, 2 insertions(+), 2 deletions(-)
> > >
> > > Applied. Thanks.
> >
> > Thanks Viresh for the offline update on applying this patch to cpufreq arm
> > tree. Please help share the git tree details of the same, since we need them
> > to pick this change in Google ACK and downstream tree.
>
> git://git.kernel.org/pub/scm/linux/kernel/git/vireshk/pm.git cpufreq/arm/linux-next
>
> I have pushed it out now, it will be there in linux-next soon. My
> branch is not fixed, I may end up rebasing it. Ideally, you shouldn't
> backport anything to android unless it end ups in Linus's tree, only
> then the sha id will be fixed and guaranteed not to change.

Thanks Viresh!