diff options
author | Ming Lei <ming.lei@redhat.com> | 2017-11-09 19:32:07 +0800 |
---|---|---|
committer | Jens Axboe <axboe@kernel.dk> | 2017-11-10 19:53:25 -0700 |
commit | 03e0f3a65e4da497c3b7b213c68943cbc73a2e34 (patch) | |
tree | 0eff01e06d1998f467cfff23abaebba9316b77c6 | |
parent | e3d7874dcf175cca2dca7795d6453f637ad8ba9b (diff) |
nvme-pci: avoid dereference of symbol from unloaded module
The 'remove_work' may be scheduled to run after nvme_remove()
returns since we can't simply cancel it in nvme_remove() for
avoiding deadlock. Once nvme_remove() returns, this module(nvme)
can be unloaded.
On the other hand, nvme_put_ctrl() calls ctr->ops->free_ctrl
which may point to nvme_pci_free_ctrl() in unloaded module.
This patch avoids this issue by queuing 'remove_work' via 'nvme_wq',
and flush this worqueue in nvme_exit() as suggested by Sagi.
Suggested-by: Sagi Grimberg <sagi@grimberg.me>
Signed-off-by: Ming Lei <ming.lei@redhat.com>
Reviewed-by: Keith Busch <keith.busch@intel.com>
Reviewed-by: Sagi Grimberg <sagi@grimberg.me>
Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
-rw-r--r-- | drivers/nvme/host/pci.c | 3 |
1 files changed, 2 insertions, 1 deletions
diff --git a/drivers/nvme/host/pci.c b/drivers/nvme/host/pci.c index 429d56f1a19e..762b8402e04c 100644 --- a/drivers/nvme/host/pci.c +++ b/drivers/nvme/host/pci.c @@ -2280,7 +2280,7 @@ static void nvme_remove_dead_ctrl(struct nvme_dev *dev, int status) nvme_get_ctrl(&dev->ctrl); nvme_dev_disable(dev, false); - if (!schedule_work(&dev->remove_work)) + if (!queue_work(nvme_wq, &dev->remove_work)) nvme_put_ctrl(&dev->ctrl); } @@ -2703,6 +2703,7 @@ static int __init nvme_init(void) static void __exit nvme_exit(void) { pci_unregister_driver(&nvme_driver); + flush_workqueue(nvme_wq); _nvme_check_size(); } |