lightnvm: prevent race condition on pblk remove

When we trigger nvm target remove during device hot unplug, there is
a probability to hit a general protection fault. This is caused by use
of nvm_dev thay may be freed from another (hot unplug) thread
(in the nvm_unregister function).

Introduce lock in nvme_ioctl_dev_remove function to prevent this
situation.

Signed-off-by: Marcin Dziegielewski <[email protected]>
Reviewed-by: Javier González <[email protected]>
Signed-off-by: Matias Bjørling <[email protected]>
Signed-off-by: Jens Axboe <[email protected]>
This commit is contained in:
Marcin Dziegielewski 2019-05-04 20:37:58 +02:00 • committed by Jens Axboe
commit f41d427cdd

View file

@ -1340,11 +1340,13 @@ static long nvm_ioctl_dev_remove(struct file *file, void __user *arg)
return -EINVAL;
}
down_read(&nvm_lock);
list_for_each_entry(dev, &nvm_devices, devices) {
ret = nvm_remove_tgt(dev, &remove);
if (!ret)
break;
}
up_read(&nvm_lock);
return ret;
}