Re: [PATCH V4 6/7] nvme: pci: prepare for supporting error recovery from resetting context

[Ming Lei <ming.lei@redhat.com>]

On Mon, May 07, 2018 at 08:04:18AM -0700, James Smart wrote:
> 
> 
> On 5/5/2018 6:59 AM, Ming Lei wrote:
> > --- a/drivers/nvme/host/pci.c
> > +++ b/drivers/nvme/host/pci.c
> > @@ -2365,14 +2365,14 @@ static void nvme_remove_dead_ctrl(struct nvme_dev *dev, int status)
> >   		nvme_put_ctrl(&dev->ctrl);
> >   }
> > -static void nvme_reset_work(struct work_struct *work)
> > +static void nvme_reset_dev(struct nvme_dev *dev)
> >   {
> > -	struct nvme_dev *dev =
> > -		container_of(work, struct nvme_dev, ctrl.reset_work);
> >   	bool was_suspend = !!(dev->ctrl.ctrl_config & NVME_CC_SHN_NORMAL);
> >   	int result = -ENODEV;
> >   	enum nvme_ctrl_state new_state = NVME_CTRL_LIVE;
> > +	mutex_lock(&dev->ctrl.reset_lock);
> > +
> >   	if (WARN_ON(dev->ctrl.state != NVME_CTRL_RESETTING))
> >   		goto out;
> 
> I believe the reset_lock is unnecessary (patch 5) as it should be covered by
> the transition of the state to RESETTING which is done under lock.
> 
> Thus the error is:
> instead of:
> ���� if (WARN_ON(dev->ctrl.state != NVME_CTRL_RESETTING))
> ���� ��� goto out;
> 
> it should be:
> ���� if (dev->ctrl.state != NVME_CTRL_RESETTING))
> ���� ��� return;
> 

Right, I have dropped this patch in V5(not posted yet):

https://github.com/ming1/linux/commits/v4.17-rc-nvme-timeout.V5

Thanks,
Ming