RE: [PATCH 00/24] Thunderbolt security levels and NVM firmware upgrade

[Mario.Limonciello]

> -----Original Message-----
> From: Bernat, Yehezkel [mailto:yehezkel.bernat@xxxxxxxxx]
> Sent: Monday, May 22, 2017 3:11 PM
> To: Limonciello, Mario <Mario_Limonciello@xxxxxxxx>;
> mika.westerberg@xxxxxxxxxxxxxxx
> Cc: gregkh@xxxxxxxxxxxxxxxxxxx; andreas.noever@xxxxxxxxx; Jamet, Michael
> <michael.jamet@xxxxxxxxx>; lukas@xxxxxxxxx; Levy, Amir (Jer)
> <amir.jer.levy@xxxxxxxxx>; luto@xxxxxxxxxx; Dominguez, Jared
> <Jared_Dominguez@xxxxxxxx>; andriy.shevchenko@xxxxxxxxxxxxxxx; linux-
> kernel@xxxxxxxxxxxxxxx
> Subject: RE: [PATCH 00/24] Thunderbolt security levels and NVM firmware upgrade
> 
> 
> 
> > -----Original Message-----
> > From: Mario.Limonciello@xxxxxxxx [mailto:Mario.Limonciello@xxxxxxxx]
> > Sent: Monday, May 22, 2017 23:08
> > To: mika.westerberg@xxxxxxxxxxxxxxx
> > Cc: gregkh@xxxxxxxxxxxxxxxxxxx; andreas.noever@xxxxxxxxx; Jamet,
> > Michael <michael.jamet@xxxxxxxxx>; Bernat, Yehezkel
> > <yehezkel.bernat@xxxxxxxxx>; lukas@xxxxxxxxx; Levy, Amir (Jer)
> > <amir.jer.levy@xxxxxxxxx>; luto@xxxxxxxxxx; Jared.Dominguez@xxxxxxxx;
> > andriy.shevchenko@xxxxxxxxxxxxxxx; linux-kernel@xxxxxxxxxxxxxxx
> > Subject: RE: [PATCH 00/24] Thunderbolt security levels and NVM firmware
> > upgrade
> >
> > > -----Original Message-----
> > > From: Mika Westerberg [mailto:mika.westerberg@xxxxxxxxxxxxxxx]
> > > Sent: Monday, May 22, 2017 6:37 AM
> > > To: Limonciello, Mario <Mario_Limonciello@xxxxxxxx>
> > > Cc: gregkh@xxxxxxxxxxxxxxxxxxx; andreas.noever@xxxxxxxxx;
> > > michael.jamet@xxxxxxxxx; yehezkel.bernat@xxxxxxxxx; lukas@xxxxxxxxx;
> > > amir.jer.levy@xxxxxxxxx; luto@xxxxxxxxxx; Dominguez, Jared
> > > <Jared_Dominguez@xxxxxxxx>; andriy.shevchenko@xxxxxxxxxxxxxxx;
> > linux-
> > > kernel@xxxxxxxxxxxxxxx
> > > Subject: Re: [PATCH 00/24] Thunderbolt security levels and NVM firmware
> > upgrade
> > >
> > > On Sat, May 20, 2017 at 11:24:12AM +0300, Mika Westerberg wrote:
> > > > On Fri, May 19, 2017 at 05:54:37PM +0000, Mario.Limonciello@xxxxxxxx
> > wrote:
> > > > > >
> > > > > > It happens occasionally when you reboot the machine when a device
> > is
> > > > > > connected but seems to be dependent on the BIOS version. Since it is
> > the
> > > > > > BIOS who is supposed to enumerated these devices, I suspect that it
> > is
> > > > > > either problem in BIOS or our PCI enumeration code does something
> > wrong.
> > > > > >
> > > > >
> > > > > I'm fairly certain it's an issue somewhere with Linux PCI enumeration.  I
> > took
> > > > > the exact same HW and switched it out the SSD to one w/ Win10 1607.
> > > > > I set the dock and cable to "always allow" in TBT settings applet.
> > > > >
> > > > > I don't reproduce any problems with enumeration with the dock
> > plugged in
> > > > > on cold boot.  All the devices hanging off the bridge show up properly.
> > > >
> > > > You mean in Windows you don't reproduce the problem, right? Even
> > when
> > > > you reboot the machine with devices connected.
> > > >
> > > > I tried on Intel Skull Canyon NUC so that I disabled the thunderbolt
> > > > driver and after reboot (warm) I can see the PCI scan error about bus
> > > > being partially hidden behind a bridge.
> > > >
> > > > When this happens PCIe ports of the thunderbolt device/host seem to
> > be
> > > > unconfigured and Linux then decides to reconfigure them which leads to
> > > > the problem. When it works we get ACPI hotplug event to the PCIe root
> > > > port and the PCIe upstream/downstream ports are properly configured
> > by
> > > > the BIOS.
> > > >
> > > > I guess Windows does something differently here than what we do when
> > PCI
> > > > devices are enumerated.
> > >
> > > We discussed this with our BIOS/firmware people and there was a
> > firmware
> > > bug that caused many issues around hotplug and reboot flows. Is is
> > > possible for you to try with the latest BIOS and see if the issue
> > > reproduces (or are you already running the latest)?
> >
> > I was 1 version behind, but I double checked with the latest version (1.1.15)
> > and the same behavior exists on Linux (still works properly on Win10).
> >
> > If you have some more details about what the FW guys changed, I can check
> > with my Dell FW team if they've picked up the same fix.  I'm guessing it's not
> > the same problem though considering it works properly on Win10?
> 
> What about the TBT NVM version?
> NVM 16 sounds a bit old to me.

16 is the latest available for the XPS 9350.  I'd guess it's got to do with the stepping
of AR, but I don't know for sure.