Re: [PATCH V2 1/1] nvme: fix multiple ctrl removal scheduling

From: Christoph Hellwig
Date: Thu May 25 2017 - 04:30:42 EST


> diff --git a/drivers/nvme/host/pci.c b/drivers/nvme/host/pci.c
> index 4c2ff2b..ba54e2a 100644
> --- a/drivers/nvme/host/pci.c
> +++ b/drivers/nvme/host/pci.c
> @@ -1903,9 +1903,6 @@ static void nvme_reset_work(struct work_struct *work)
> bool was_suspend = !!(dev->ctrl.ctrl_config & NVME_CC_SHN_NORMAL);
> int result = -ENODEV;
>
> - if (WARN_ON(dev->ctrl.state == NVME_CTRL_RESETTING))
> - goto out;

Can we keep a

WARN_ON(dev->ctrl.state != NVME_CTRL_RESETTING))

here?

> goto out;
> @@ -2009,8 +2003,8 @@ static int nvme_reset(struct nvme_dev *dev)
> {
> if (!dev->ctrl.admin_q || blk_queue_dying(dev->ctrl.admin_q))
> return -ENODEV;
> - if (work_busy(&dev->reset_work))
> - return -ENODEV;
> + if (!nvme_change_ctrl_state(&dev->ctrl, NVME_CTRL_RESETTING))
> + return -EBUSY;
> if (!queue_work(nvme_workq, &dev->reset_work))
> return -EBUSY;

nvme_probe will also have to set the state to NVME_CTRL_RESETTING to
keep the old behavior, which had some error handling implications.

Also we can replace the work_busy(&dev->reset_work) check in
nvme_should_reset with a check for the NVME_CTRL_RESETTING state now.