Messages in this thread | | | Date | Thu, 11 Jun 2015 17:49:28 -0400 | From | Jarod Wilson <> | Subject | Re: [Update][PATCH] PCIe / hotplug: Drop pointless ACPI-based "slot detection" check |
| |
On 6/11/2015 5:16 PM, Rafael J. Wysocki wrote: > On Thursday, June 11, 2015 04:38:12 PM Jarod Wilson wrote: >> On 6/11/2015 1:05 PM, Jarod Wilson wrote: >>> On 5/21/2015 9:21 PM, Rafael J. Wysocki wrote: >>>> On Thursday, May 21, 2015 11:11:46 AM Bjorn Helgaas wrote: >>>>> On Tue, May 19, 2015 at 03:27:58PM +0200, Rafael J. Wysocki wrote: >>>>>> From: Rafael J. Wysocki <rafael.j.wysocki@intel.com> >>>>>> >>>>>> Jarod Wilson reports that the expresscard hotplug setup doesn't work >>>>>> on HP ZBook G2. The problem turns out to be the ACPI-based "slot >>>>>> detection" code called from pciehp_probe() which tries to use some >>>>>> questionable heuristics based on what ACPI objects are present for >>>>>> the PCIe port device at hand to figure out whether or not to register >>>>>> a hotplug slot for that port. >>>>>> >>>>>> That code is used if there is at least one PCIe port having an ACPI >>>>>> device configuration object related to hotplug (such as _EJ0 or _RMV) >>>>>> and the Thunderbolt port on the affected machine has _RMV. Of course, >>>>>> Thunderbolt and PCIe native hotplug need not be mutually exclusive >>>>>> (as they aren't on the machine in question), so that rule is simply >>>>>> incorrect. >>>>>> >>>>>> Moreover, the ACPI-based "slot detection" check does not add any >>>>>> value if pciehp_probe() is called at all and the service type of the >>>>>> device object it has been called for is PCIE_PORT_SERVICE_HP, because >>>>>> PCIe hotplug services are only registered if the _OSC handshake in >>>>>> acpi_pci_root_add() allows the kernel to control the PCIe native >>>>>> hotplug feature. No more checks need to be carried out to decide >>>>>> whether or not to register a native PCIe hotlug slot in that case. >>>>>> >>>>>> For the above reasons, make pciehp_probe() check if it has been >>>>>> called for the right service type and drop the pointless ACPI-based >>>>>> "slot detection" check from it. Also remove the entire code whose >>>>>> only user is that check (the entire pciehp_acpi.c file goes away >>>>>> as a result) and drop function headers related to it from the >>>>>> internal PCIeHP header file. >>>>>> >>>>>> Link: http://marc.info/?t=143163219300002&r=1&w=2 >>>>>> Link: https://bugzilla.kernel.org/show_bug.cgi?id=98581 >>>>>> Reported-by: Jarod Wilson <jarod@redhat.com> >>>>>> Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com> >>>>> >>>>> This is awesome! Applied to pci/hotplug for v4.2, with Jarod's >>>>> reviewed/tested-by. >>>> >>>> Thanks! >>> >>> Looks like I didn't test enough. I can't explain WHY, but with this >>> applied, now thunderbolt hot unplug of a network adapter goes haywire, >>> where prior to the patch, it worked just fine. Still looking into it... >> >> Filed bug, dmesg spew can be found in the bug. >> >> https://bugzilla.kernel.org/show_bug.cgi?id=99841 > > If it worked for you previously, can you possibly try to re-create that > configuration and set of patches applied and retest then?
I tried the current Fedora 4.1-rc7 build first, everything was fine, then patched in JUST the one patch, and it went belly up. I'll add some extra debugging spew to a build both with and without the one patch, to see what differences there are in devices pciehp is claiming and follow up in the bug on your other info requests.
-- Jarod Wilson jarod@redhat.com
| |