[PATCH AUTOSEL 4.19 058/237] nvme-pci: fix hot removal during error handling

Sasha Levin
2019-11-16T15:42:18Z

From: Keith Busch <keith.busch@intel.com>

[ Upstream commit cb4bfda62afa25b4eee3d635d33fccdd9485dd7c ]

A removal waits for the reset_work to complete. If a surprise removal
occurs around the same time as an error triggered controller reset, and
reset work happened to dispatch a command to the removed controller, the
command won't be recovered since the timeout work doesn't do anything
during error recovery. We wouldn't want to wait for timeout handling
anyway, so this patch fixes this by disabling the controller and killing
admin queues prior to syncing with the reset_work.

Signed-off-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: Sasha Levin <sashal@kernel.org>
---
drivers/nvme/host/pci.c | 3 +--
1 file changed, 1 insertion(+), 2 deletions(-)

diff --git a/drivers/nvme/host/pci.c b/drivers/nvme/host/pci.c
index a64a8bca0d5b9..9479c0db08f62 100644
--- a/drivers/nvme/host/pci.c
+++ b/drivers/nvme/host/pci.c
@@ -2583,13 +2583,12 @@ static void nvme_remove(struct pci_dev *pdev)
struct nvme_dev *dev = pci_get_drvdata(pdev);

nvme_change_ctrl_state(&dev->ctrl, NVME_CTRL_DELETING);
-
- cancel_work_sync(&dev->ctrl.reset_work);
pci_set_drvdata(pdev, NULL);

if (!pci_device_is_present(pdev)) {
nvme_change_ctrl_state(&dev->ctrl, NVME_CTRL_DEAD);
nvme_dev_disable(dev, true);
+ nvme_dev_remove_admin(dev);
}

flush_work(&dev->ctrl.reset_work);
--
2.20.1