Re: [REGRESSION][BISECTED] "xHCI host controller not responding, assume dead" on stable kernel > 6.8.7

From: Mario Limonciello
Date: Mon May 20 2024 - 10:42:00 EST


On 5/20/2024 09:39, Christian Heusel wrote:
On 24/05/06 02:53PM, Linux regression tracking (Thorsten Leemhuis) wrote:
[CCing Mario, who asked for the two suspected commits to be backported]

On 06.05.24 14:24, Gia wrote:
Hello, from 6.8.7=>6.8.8 I run into a similar problem with my Caldigit
TS3 Plus Thunderbolt 3 dock.

After the update I see this message on boot "xHCI host controller not
responding, assume dead" and the dock is not working anymore. Kernel
6.8.7 works great.

We now have some further information on the matter as somebody was kind
enough to bisect the issue in the [Arch Linux Forums][0]:

cc4c94a5f6c4 ("thunderbolt: Reset topology created by the boot firmware")

This is a stable commit id, the relevant mainline commit is:

59a54c5f3dbd ("thunderbolt: Reset topology created by the boot firmware")

The other reporter created [a issue][1] in our bugtracker, which I'll
leave here just for completeness sake.

Reported-by: Benjamin Böhmke <benjamin@xxxxxxxxxxx>
Reported-by: Gia <giacomo.gio@xxxxxxxxx>
Bisected-by: Benjamin Böhmke <benjamin@xxxxxxxxxxx>

The person doing the bisection also offered to chime in here if further
debugging is needed!

Also CC'ing the Commitauthors & Subsystem Maintainers for this report.

Cheers,
Christian

[0]: https://bbs.archlinux.org/viewtopic.php?pid=2172526
[1]: https://gitlab.archlinux.org/archlinux/packaging/packages/linux/-/issues/48

#regzbot introduced: 59a54c5f3dbd
#regzbot link: https://gitlab.archlinux.org/archlinux/packaging/packages/linux/-/issues/48

As I mentioned in my other email I would like to collate logs onto a kernel Bugzilla. With these two cases:

thunderbolt.dyndbg=+p
thunderbolt.dyndbg=+p thunderbolt.host_reset=false

Also what is the value for:

$ cat /sys/bus/thunderbolt/devices/domain0/iommu_dma_protection