Hello Patrick, What do you think about the following minor changes: On Tue, Jan 15, 2019 at 10:14:58AM +0000, Patrick Bellasi wrote: > /* SCHED_ISO: reserved but not implemented yet */ > #define SCHED_IDLE 5 > #define SCHED_DEADLINE 6 > +/* Must be the last entry: used to sanity check attr.policy values */ I would remove this comment: - the meaning of SCHED_POLICY_MAX is evident, and - should we hint on how the value is used? That comment will be removed the next time SCHED_POLICY_MAX is used for something else. This is what should also happen to the comment of SETPARAM_POLICY: now sched_setparam() is no more the only code path accessing SETPARAM_POLICY. > +#define SCHED_POLICY_MAX 7 +#define SCHED_POLICY_MAX SCHED_DEADLINE This would make it compliant with the definition of MAX. > --- a/kernel/sched/core.c > +++ b/kernel/sched/core.c > @@ -4560,8 +4560,17 @@ SYSCALL_DEFINE3(sched_setattr, pid_t, pid, struct sched_attr __user *, uattr, > if (retval) > return retval; > > - if ((int)attr.sched_policy < 0) > + /* > + * A valid policy is always required from userspace, unless > + * SCHED_FLAG_KEEP_POLICY is set and the current policy > + * is enforced for this call. > + */ > + if (attr.sched_policy >= SCHED_POLICY_MAX && + if (attr.sched_policy > SCHED_POLICY_MAX && In line with the previous update. > + !(attr.sched_flags & SCHED_FLAG_KEEP_POLICY)) { > return -EINVAL; Thanks, Alessio