Commit ee6fdc50 authored by Michael Liang's avatar Michael Liang Committed by Keith Busch
Browse files

nvme-fc: fix race between error recovery and creating association 



There is a small race window between nvme-fc association creation and error
recovery. Fix this race condition by protecting accessing to controller
state and ASSOC_FAILED flag under nvme-fc controller lock.

Signed-off-by: default avatarMichael Liang <mliang@purestorage.com>
Reviewed-by: default avatarCaleb Sander <csander@purestorage.com>
Reviewed-by: default avatarJames Smart <jsmart2021@gmail.com>
Signed-off-by: default avatarKeith Busch <kbusch@kernel.org>
parent 60e445bd

drivers/nvme/host/fc.c

+16 −5
Original line number Diff line number Diff line
@@ -2548,17 +2548,24 @@ nvme_fc_error_recovery(struct nvme_fc_ctrl *ctrl, char *errmsg) 
	 * the controller.  Abort any ios on the association and let the

	 * create_association error path resolve things.

	 */

	if (ctrl->ctrl.state == NVME_CTRL_CONNECTING) {

		__nvme_fc_abort_outstanding_ios(ctrl, true);

	enum nvme_ctrl_state state;

	unsigned long flags;



	spin_lock_irqsave(&ctrl->lock, flags);

	state = ctrl->ctrl.state;

	if (state == NVME_CTRL_CONNECTING) {

		set_bit(ASSOC_FAILED, &ctrl->flags);

		spin_unlock_irqrestore(&ctrl->lock, flags);

		__nvme_fc_abort_outstanding_ios(ctrl, true);

		dev_warn(ctrl->ctrl.device,

			"NVME-FC{%d}: transport error during (re)connect\n",

			ctrl->cnum);

		return;

	}

	spin_unlock_irqrestore(&ctrl->lock, flags);



	/* Otherwise, only proceed if in LIVE state - e.g. on first error */

	if (ctrl->ctrl.state != NVME_CTRL_LIVE)

	if (state != NVME_CTRL_LIVE)

		return;



	dev_warn(ctrl->ctrl.device,
@@ -3172,12 +3179,16 @@ nvme_fc_create_association(struct nvme_fc_ctrl *ctrl) 
		else

			ret = nvme_fc_recreate_io_queues(ctrl);

	}



	spin_lock_irqsave(&ctrl->lock, flags);

	if (!ret && test_bit(ASSOC_FAILED, &ctrl->flags))

		ret = -EIO;

	if (ret)

	if (ret) {

		spin_unlock_irqrestore(&ctrl->lock, flags);

		goto out_term_aen_ops;



	}

	changed = nvme_change_ctrl_state(&ctrl->ctrl, NVME_CTRL_LIVE);

	spin_unlock_irqrestore(&ctrl->lock, flags);



	ctrl->ctrl.nr_reconnects = 0;