diff options
Diffstat (limited to 'kernel/exit.c')
| -rw-r--r-- | kernel/exit.c | 33 |
1 files changed, 9 insertions, 24 deletions
diff --git a/kernel/exit.c b/kernel/exit.c index 8714e5ded8b4..6806c55475ee 100644 --- a/kernel/exit.c +++ b/kernel/exit.c @@ -212,27 +212,6 @@ repeat: } /* - * This checks not only the pgrp, but falls back on the pid if no - * satisfactory pgrp is found. I dunno - gdb doesn't work correctly - * without this... - * - * The caller must hold rcu lock or the tasklist lock. - */ -struct pid *session_of_pgrp(struct pid *pgrp) -{ - struct task_struct *p; - struct pid *sid = NULL; - - p = pid_task(pgrp, PIDTYPE_PGID); - if (p == NULL) - p = pid_task(pgrp, PIDTYPE_PID); - if (p != NULL) - sid = task_session(p); - - return sid; -} - -/* * Determine if a process group is "orphaned", according to the POSIX * definition in 2.2.2.52. Orphaned process groups are not to be affected * by terminal-generated stop signals. Newly orphaned process groups are @@ -1308,9 +1287,15 @@ static int wait_task_continued(struct wait_opts *wo, struct task_struct *p) static int wait_consider_task(struct wait_opts *wo, int ptrace, struct task_struct *p) { + /* + * We can race with wait_task_zombie() from another thread. + * Ensure that EXIT_ZOMBIE -> EXIT_DEAD/EXIT_TRACE transition + * can't confuse the checks below. + */ + int exit_state = ACCESS_ONCE(p->exit_state); int ret; - if (unlikely(p->exit_state == EXIT_DEAD)) + if (unlikely(exit_state == EXIT_DEAD)) return 0; ret = eligible_child(wo, p); @@ -1331,7 +1316,7 @@ static int wait_consider_task(struct wait_opts *wo, int ptrace, return 0; } - if (unlikely(p->exit_state == EXIT_TRACE)) { + if (unlikely(exit_state == EXIT_TRACE)) { /* * ptrace == 0 means we are the natural parent. In this case * we should clear notask_error, debugger will notify us. @@ -1358,7 +1343,7 @@ static int wait_consider_task(struct wait_opts *wo, int ptrace, } /* slay zombie? */ - if (p->exit_state == EXIT_ZOMBIE) { + if (exit_state == EXIT_ZOMBIE) { /* we don't reap group leaders with subthreads */ if (!delay_group_leader(p)) { /* |