On Tue, 15 Jul 2014, Ley Foon Tan wrote: +static inline int atomic_futex_op_xchg_set(int oparg, u32 __user *uaddr, > + int *oldval) > +{ > + unsigned long flags; > + int ret; > + > + local_irq_save(flags); > + > + ret = get_user(*oldval, uaddr); > + if (!ret) > + ret = put_user(oparg, uaddr);
This is wrong as it gets. get_user() might fault and sleep. You need a proper implementation, which handles fault exceptions. Thanks, tglx -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majord...@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/