Re: [bug report from blktests nvme/032] WARNING: possible circular locking dependency detected

[Christoph Hellwig]

On Tue, Jun 28, 2022 at 08:07:52AM +0200, Greg Kroah-Hartman wrote:
> On Tue, Jun 28, 2022 at 04:03:55AM +0000, yangx.jy@xxxxxxxxxxx wrote:
> > Hi everyone,
> > 
> > Running blktests nvme/032 on kernel v5.19-rc2+ which enables 
> > CONFIG_LOCKDEP and CONFIG_PROVE_LOCKING triggered the below WARNING.
> 
> What was happening when this trace was created?  It looks like you were
> manually removing a PCI device from the system through sysfs?  Why would
> blktests do that?

To test how the block layer copes with the fact that the underlying
device goes away.