diff options
Diffstat (limited to 'drivers/infiniband/core/uverbs_main.c')
| -rw-r--r-- | drivers/infiniband/core/uverbs_main.c | 56 |
1 files changed, 51 insertions, 5 deletions
diff --git a/drivers/infiniband/core/uverbs_main.c b/drivers/infiniband/core/uverbs_main.c index 4445d8ee9314..2094d136513d 100644 --- a/drivers/infiniband/core/uverbs_main.c +++ b/drivers/infiniband/core/uverbs_main.c @@ -41,6 +41,8 @@ #include <linux/fs.h> #include <linux/poll.h> #include <linux/sched.h> +#include <linux/sched/mm.h> +#include <linux/sched/task.h> #include <linux/file.h> #include <linux/cdev.h> #include <linux/anon_inodes.h> @@ -734,10 +736,6 @@ static ssize_t ib_uverbs_write(struct file *filp, const char __user *buf, if (ret) return ret; - if (!file->ucontext && - (command != IB_USER_VERBS_CMD_GET_CONTEXT || extended)) - return -EINVAL; - if (extended) { if (count < (sizeof(hdr) + sizeof(ex_hdr))) return -EINVAL; @@ -757,6 +755,16 @@ static ssize_t ib_uverbs_write(struct file *filp, const char __user *buf, goto out; } + /* + * Must be after the ib_dev check, as once the RCU clears ib_dev == + * NULL means ucontext == NULL + */ + if (!file->ucontext && + (command != IB_USER_VERBS_CMD_GET_CONTEXT || extended)) { + ret = -EINVAL; + goto out; + } + if (!verify_command_mask(ib_dev, command, extended)) { ret = -EOPNOTSUPP; goto out; @@ -1090,6 +1098,44 @@ err: return; } +static void ib_uverbs_disassociate_ucontext(struct ib_ucontext *ibcontext) +{ + struct ib_device *ib_dev = ibcontext->device; + struct task_struct *owning_process = NULL; + struct mm_struct *owning_mm = NULL; + + owning_process = get_pid_task(ibcontext->tgid, PIDTYPE_PID); + if (!owning_process) + return; + + owning_mm = get_task_mm(owning_process); + if (!owning_mm) { + pr_info("no mm, disassociate ucontext is pending task termination\n"); + while (1) { + put_task_struct(owning_process); + usleep_range(1000, 2000); + owning_process = get_pid_task(ibcontext->tgid, + PIDTYPE_PID); + if (!owning_process || + owning_process->state == TASK_DEAD) { + pr_info("disassociate ucontext done, task was terminated\n"); + /* in case task was dead need to release the + * task struct. + */ + if (owning_process) + put_task_struct(owning_process); + return; + } + } + } + + down_write(&owning_mm->mmap_sem); + ib_dev->disassociate_ucontext(ibcontext); + up_write(&owning_mm->mmap_sem); + mmput(owning_mm); + put_task_struct(owning_process); +} + static void ib_uverbs_free_hw_resources(struct ib_uverbs_device *uverbs_dev, struct ib_device *ib_dev) { @@ -1130,7 +1176,7 @@ static void ib_uverbs_free_hw_resources(struct ib_uverbs_device *uverbs_dev, * (e.g mmput). */ ib_uverbs_event_handler(&file->event_handler, &event); - ib_dev->disassociate_ucontext(ucontext); + ib_uverbs_disassociate_ucontext(ucontext); mutex_lock(&file->cleanup_mutex); ib_uverbs_cleanup_ucontext(file, ucontext, true); mutex_unlock(&file->cleanup_mutex); |