Re: [Bug 216859] New: PCI bridge to bus boot hang at enumeration

From: Bjorn Helgaas
Date: Wed Dec 28 2022 - 13:42:46 EST


On Wed, Dec 28, 2022 at 06:42:38PM +0100, Zeno Davatz wrote:
> Dear Bjorn
>
> On Wed, Dec 28, 2022 at 1:02 PM Bjorn Helgaas <helgaas@xxxxxxxxxx> wrote:
> >
> > [+cc linux-pci, linux-kernel]
> >
> > On Wed, Dec 28, 2022 at 08:37:52AM +0000, bugzilla-daemon@xxxxxxxxxx wrote:
> > > https://bugzilla.kernel.org/show_bug.cgi?id=216859
> >
> > > Summary: PCI bridge to bus boot hang at enumeration
> > > Kernel Version: 6.1-rc1
> > > ...
> >
> > > With Kernel 6.1-rc1 the enumeration process stopped working for me,
> > > see attachments.
> > >
> > > The enumeration works fine with Kernel 6.0 and below.
> > >
> > > Same problem still exists with v6.1. and v6.2.-rc1
> >
> > Thank you very much for your report, Zeno!
> >
> > v6.0 works, v6.1-rc1 fails. Would you mind booting v6.1-rc1 with the
> > "ignore_loglevel initcall_debug" kernel parameters and taking a photo
> > when it hangs?
>
> I will try this after Januar 7th 2023.

Sounds good, thanks!

> > How did you conclude that the hang is related to a PCI bridge? I see
> > recent PCI messages in the photo, but it looks like the last message
> > is from NFS, so I'm wondering if I'm missing some context. The v6.0
> > dmesg shows several other ntfs, fuse, JFS, etc messages before more
> > PCI-related things. Anyway, the "initcall_debug" might help us narrow
> > it down a bit.
>
> I did not really conclude that. I just saw "PCI" as one of the last
> messages being outputted before the boot process stopped.

OK. We'll figure it out!

Bjorn