From: Josh Don <joshdon@xxxxxxxxxx> commit fcdb1eda5302599045bb366e679cccb4216f3873 upstream. We need to reset forceidle_sum to 0 when reading from root, since the bstat we accumulate into is stack allocated. To make this more robust, just replace the existing cputime reset with a memset of the overall bstat. Signed-off-by: Josh Don <joshdon@xxxxxxxxxx> Fixes: 1fcf54deb767 ("sched/core: add forced idle accounting for cgroups") Cc: stable@xxxxxxxxxxxxxxx # v6.0+ Signed-off-by: Tejun Heo <tj@xxxxxxxxxx> Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx> --- kernel/cgroup/rstat.c | 4 +--- 1 file changed, 1 insertion(+), 3 deletions(-) --- a/kernel/cgroup/rstat.c +++ b/kernel/cgroup/rstat.c @@ -457,9 +457,7 @@ static void root_cgroup_cputime(struct c struct task_cputime *cputime = &bstat->cputime; int i; - cputime->stime = 0; - cputime->utime = 0; - cputime->sum_exec_runtime = 0; + memset(bstat, 0, sizeof(*bstat)); for_each_possible_cpu(i) { struct kernel_cpustat kcpustat; u64 *cpustat = kcpustat.cpustat;