diff options
Diffstat (limited to 'kernel')
| -rw-r--r-- | kernel/fork.c | 42 | ||||
| -rw-r--r-- | kernel/sched.c | 4 |
2 files changed, 24 insertions, 22 deletions
diff --git a/kernel/fork.c b/kernel/fork.c index f89734b831ac..27cf572cedf8 100644 --- a/kernel/fork.c +++ b/kernel/fork.c @@ -408,16 +408,16 @@ void mm_release(void) tsk->vfork_done = NULL; complete(vfork_done); } - if (tsk->user_tid) { - int * user_tid = tsk->user_tid; - tsk->user_tid = NULL; + if (tsk->clear_child_tid) { + int * tidptr = tsk->clear_child_tid; + tsk->clear_child_tid = NULL; /* * We dont check the error code - if userspace has * not set up a proper pointer then tough luck. */ - put_user(0, user_tid); - sys_futex((unsigned long)user_tid, FUTEX_WAKE, 1, NULL); + put_user(0, tidptr); + sys_futex((unsigned long)tidptr, FUTEX_WAKE, 1, NULL); } } @@ -680,9 +680,9 @@ static inline void copy_flags(unsigned long clone_flags, struct task_struct *p) p->flags = new_flags; } -asmlinkage int sys_set_tid_address(int *user_tid) +asmlinkage int sys_set_tid_address(int *tidptr) { - current->user_tid = user_tid; + current->clear_child_tid = tidptr; return current->pid; } @@ -699,7 +699,8 @@ static struct task_struct *copy_process(unsigned long clone_flags, unsigned long stack_start, struct pt_regs *regs, unsigned long stack_size, - int *user_tid) + int *parent_tidptr, + int *child_tidptr) { int retval; struct task_struct *p = NULL; @@ -766,6 +767,11 @@ static struct task_struct *copy_process(unsigned long clone_flags, if (p->pid == -1) goto bad_fork_cleanup; } + retval = -EFAULT; + if (clone_flags & CLONE_PARENT_SETTID) + if (put_user(p->pid, parent_tidptr)) + goto bad_fork_cleanup; + p->proc_dentry = NULL; INIT_LIST_HEAD(&p->run_list); @@ -823,19 +829,14 @@ static struct task_struct *copy_process(unsigned long clone_flags, retval = copy_thread(0, clone_flags, stack_start, stack_size, p, regs); if (retval) goto bad_fork_cleanup_namespace; - /* - * Notify the child of the TID? - */ - retval = -EFAULT; - if (clone_flags & CLONE_SETTID) - if (put_user(p->pid, user_tid)) - goto bad_fork_cleanup_namespace; + if (clone_flags & CLONE_CHILD_SETTID) + p->set_child_tid = child_tidptr; /* - * Does the userspace VM want the TID cleared on mm_release()? + * Clear TID on mm_release()? */ - if (clone_flags & CLONE_CLEARTID) - p->user_tid = user_tid; + if (clone_flags & CLONE_CHILD_CLEARTID) + p->clear_child_tid = child_tidptr; /* * Syscall tracing should be turned off in the child regardless @@ -1004,7 +1005,8 @@ struct task_struct *do_fork(unsigned long clone_flags, unsigned long stack_start, struct pt_regs *regs, unsigned long stack_size, - int *user_tid) + int *parent_tidptr, + int *child_tidptr) { struct task_struct *p; int trace = 0; @@ -1015,7 +1017,7 @@ struct task_struct *do_fork(unsigned long clone_flags, clone_flags |= CLONE_PTRACE; } - p = copy_process(clone_flags, stack_start, regs, stack_size, user_tid); + p = copy_process(clone_flags, stack_start, regs, stack_size, parent_tidptr, child_tidptr); if (!IS_ERR(p)) { struct completion vfork; diff --git a/kernel/sched.c b/kernel/sched.c index 6d0ac320bcbc..b446ce8eecc1 100644 --- a/kernel/sched.c +++ b/kernel/sched.c @@ -503,12 +503,12 @@ void sched_exit(task_t * p) * schedule_tail - first thing a freshly forked thread must call. * @prev: the thread we just switched away from. */ -#if CONFIG_SMP || CONFIG_PREEMPT asmlinkage void schedule_tail(task_t *prev) { finish_arch_switch(this_rq(), prev); + if (current->set_child_tid) + put_user(current->pid, current->set_child_tid); } -#endif /* * context_switch - switch to the new MM and the new |