From mboxrd@z Thu Jan  1 00:00:00 1970
From: kbusch@kernel.org (Keith Busch)
Date: Mon, 8 Apr 2019 09:07:51 -0600
Subject: A kernel warning when entering suspend
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Message-ID: <20190408150750.GB32498@localhost.localdomain>

On Sat, Apr 06, 2019@09:12:12AM -0700, fin4478 fin4478 wrote:
> On Sat, 6 Apr 2019 23:31:51 +0800
> Dongli Zhang <dongli.zhang@oracle.com> wrote:
> 
> 
> > I am not able to reproduce anymore with below patch:
> > 
> > diff --git a/drivers/nvme/host/pci.c b/drivers/nvme/host/pci.c
> > index a90cf5d..90f6e80 100644
> > --- a/drivers/nvme/host/pci.c
> > +++ b/drivers/nvme/host/pci.c
> > @@ -1083,6 +1083,9 @@ static int nvme_poll_irqdisable(struct
> > nvme_queue *nvmeq, unsigned int tag)
> >         u16 start, end;
> >         int found;
> > 
> > +       if (!nvme_cqe_pending(nvmeq))
> > +               return 0;
> > +
> >         /*
> >          * For a poll queue we need to protect against the polling
> > thread
> >          * using the CQ lock.  For normal interrupt driven threads we
> > have
> > 
> > Dongli Zhang
> 
> Confirming. This bug is fixed with this patch.

I think the patch makes sense, though you'd still have a problem if
there is a cqe pending when you reach this point.