Re: [PATCH resend v2] PCI: pciehp: Use down_read/write_nested(reset_lock) to fix lockdep errors

[Hans de Goede <hdegoede@redhat.com>]

Hi,

On 1/12/22 09:28, Lukas Wunner wrote:
> On Tue, Jan 11, 2022 at 11:14:47AM -0600, Bjorn Helgaas wrote:
>> On Fri, Dec 17, 2021 at 03:17:09PM +0100, Hans de Goede wrote:
>>> Use down_read_nested() and down_write_nested() when taking the
>>> ctrl->reset_lock rw-sem, passing the number of PCIe hotplug controllers in
>>> the path to the PCI root bus as lock subclass parameter. This fixes the
>>> following false-positive lockdep report when unplugging a Lenovo X1C8 from
>>> a Lenovo 2nd gen TB3 dock:
> [...]
>> Applied to pci/hotplug for v5.17, thanks, Hans!
> 
> I've realized only now that Hans reported this issue already in August 2020
> and opened a bugzilla for it:
> 
> https://bugzilla.kernel.org/show_bug.cgi?id=208855

Ah I completely forgot about having filed that bug, good catch.

> The status can now be set to RESOLVED FIXED.  I don't have permission
> to do that but perhaps either of you, Bjorn or Hans, has?

I have added a comment and closed the bug now. Note that you can email
the kernel.org admins with your bugzilla login + a friendly requests
to give you some more bugzilla rights. I did that a while ago when
I hit similar issues doing triage of bugzilla.kernel.org bugs.

> Also, the commit could optionally be amended with a Link: tag to that
> bugzilla entry.

There isn't really any new info in the bugzilla though, so I guess
the commit is fine as is. With that said if Bjorn wants to add it
that is fine too of course.

Regards,

Hans