diff options
| -rw-r--r-- | drivers/infiniband/core/counters.c | 14 | ||||
| -rw-r--r-- | drivers/infiniband/core/nldev.c | 28 |
2 files changed, 33 insertions, 9 deletions
diff --git a/drivers/infiniband/core/counters.c b/drivers/infiniband/core/counters.c index 12ba2685abcf..8434ec082c3a 100644 --- a/drivers/infiniband/core/counters.c +++ b/drivers/infiniband/core/counters.c @@ -149,8 +149,18 @@ static bool auto_mode_match(struct ib_qp *qp, struct rdma_counter *counter, struct auto_mode_param *param = &counter->mode.param; bool match = true; - /* Ensure that counter belongs to the right PID */ - if (task_pid_nr(counter->res.task) != task_pid_nr(qp->res.task)) + /* + * Ensure that counter belongs to the right PID. This operation can + * race with user space which kills the process and leaves QP and + * counters orphans. + * + * It is not a big deal because exitted task will leave both QP and + * counter in the same bucket of zombie process. Just ensure that + * process is still alive before procedding. + * + */ + if (task_pid_nr(counter->res.task) != task_pid_nr(qp->res.task) || + !task_pid_nr(qp->res.task)) return false; if (auto_mask & RDMA_COUNTER_MASK_QP_TYPE) diff --git a/drivers/infiniband/core/nldev.c b/drivers/infiniband/core/nldev.c index 2f052c23c8c7..b2328550d24c 100644 --- a/drivers/infiniband/core/nldev.c +++ b/drivers/infiniband/core/nldev.c @@ -415,20 +415,34 @@ err: static int fill_res_name_pid(struct sk_buff *msg, struct rdma_restrack_entry *res) { + int err = 0; + /* * For user resources, user is should read /proc/PID/comm to get the * name of the task file. */ if (rdma_is_kernel_res(res)) { - if (nla_put_string(msg, RDMA_NLDEV_ATTR_RES_KERN_NAME, - res->kern_name)) - return -EMSGSIZE; + err = nla_put_string(msg, RDMA_NLDEV_ATTR_RES_KERN_NAME, + res->kern_name); } else { - if (nla_put_u32(msg, RDMA_NLDEV_ATTR_RES_PID, - task_pid_vnr(res->task))) - return -EMSGSIZE; + pid_t pid; + + pid = task_pid_vnr(res->task); + /* + * Task is dead and in zombie state. + * There is no need to print PID anymore. + */ + if (pid) + /* + * This part is racy, task can be killed and PID will + * be zero right here but it is ok, next query won't + * return PID. We don't promise real-time reflection + * of SW objects. + */ + err = nla_put_u32(msg, RDMA_NLDEV_ATTR_RES_PID, pid); } - return 0; + + return err ? -EMSGSIZE : 0; } static bool fill_res_entry(struct ib_device *dev, struct sk_buff *msg, |