On 5/19/2015 7:43 AM, Rafael J. Wysocki wrote:
From: Rafael J. Wysocki <rafael.j.wysocki@xxxxxxxxx> 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@xxxxxxxxxx> Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@xxxxxxxxx> --- Bjorn, that's -stable material I think. It should be applicable at least since commit 5ba113f7c4fb (PCI: acpiphp: Handle PCIe ports without native hotplug capability) that was shipped in 3.10. Thanks!
I believe you also want to rip the pciehp_acpi.o hunk out of drivers/pci/hotplug/Makefile, but I made more or less the exact same changes here, and am about to give them a spin on the ZBook 17.
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