On Thu, Apr 16, 2020 at 2:11 AM Jesper Dangaard Brouer
<brouer@xxxxxxxxxx> wrote:
>
> On Thu, 16 Apr 2020 10:31:20 +0200
> Toke Høiland-Jørgensen <toke@xxxxxxxxxx> wrote:
>
> > When the kernel is built with CONFIG_DEBUG_PER_CPU_MAPS, the cpumap code
> > can trigger a spurious warning if CONFIG_CPUMASK_OFFSTACK is also set. This
> > happens because in this configuration, NR_CPUS can be larger than
> > nr_cpumask_bits, so the initial check in cpu_map_alloc() is not sufficient
> > to guard against hitting the warning in cpumask_check().
> >
> > Fix this by explicitly checking the supplied key against the
> > nr_cpumask_bits variable before calling cpu_possible().
> >
> > Fixes: 6710e1126934 ("bpf: introduce new bpf cpu map type BPF_MAP_TYPE_CPUMAP")
> > Cc: Jesper Dangaard Brouer <brouer@xxxxxxxxxx>
> > Reported-by: Xiumei Mu <xmu@xxxxxxxxxx>
> > Tested-by: Xiumei Mu <xmu@xxxxxxxxxx>
> > Signed-off-by: Toke Høiland-Jørgensen <toke@xxxxxxxxxx>
> > ---
>
> Acked-by: Jesper Dangaard Brouer <brouer@xxxxxxxxxx>
Acked-by: Song Liu <songliubraving@xxxxxx>
