Re: [REGRESSION 5.0.8] Dell thunderbolt dock broken (xhci_hcd and thunderbolt)

[Mika Westerberg <mika.westerberg@linux.intel.com>]

On Mon, Apr 29, 2019 at 09:47:15PM +0200, Takashi Iwai wrote:
> Hi,

Hi,

> we've got a regression report wrt xhci_hcd and thunderbolt on a Dell
> machine.  5.0.7 is confirmed to work, so it must be a regression
> introduced by 5.0.8.
> 
> The details are found in openSUSE Bugzilla entry:
>   https://bugzilla.opensuse.org/show_bug.cgi?id=1132943
> 
> The probe of xhci_hcd on the dock fails like:
> [    6.269062] pcieport 0000:3a:00.0: enabling device (0006 -> 0007)
> [    6.270027] pcieport 0000:3b:03.0: enabling device (0006 -> 0007)
> [    6.270758] xhci_hcd 0000:3c:00.0: init 0000:3c:00.0 fail, -16
> [    6.270764] xhci_hcd: probe of 0000:3c:00.0 failed with error -16
> [    6.271002] xhci_hcd 0000:3d:00.0: init 0000:3d:00.0 fail, -16
> 
> and later on, thunderbolt gives warnings:
> [   30.232676] thunderbolt 0000:05:00.0: unexpected hop count: 1023
> [   30.232957] ------------[ cut here ]------------
> [   30.232958] thunderbolt 0000:05:00.0: interrupt for TX ring 0 is already enabled
> [   30.232974] WARNING: CPU: 3 PID: 1009 at drivers/thunderbolt/nhi.c:107 ring_interrupt_active+0x1ea/0x230 [thunderbolt]
> 
> 
> I blindly suspected the commit 3943af9d01e9 and asked for a reverted
> kernel, but in vain.  And now it was confirmed that the problem is
> present with the latest 5.1-rc, too.
> 
> I put some people who might have interest and the reporter (Michael)
> to Cc.  If anyone has an idea, feel free to join to the Bugzilla, or
> let me know if any help needed from the distro side.

Since it exists in 5.1-rcX also it would be good if someone
who see the problem (Michael?) could bisect it.