PCI: Enable ECRC only if device supports it
authorBjorn Helgaas <bhelgaas@google.com>
Tue, 21 Mar 2017 18:01:30 +0000 (13:01 -0500)
committerBjorn Helgaas <bhelgaas@google.com>
Wed, 28 Jun 2017 20:14:52 +0000 (15:14 -0500)
commit675734baa361cf044033bb60594dea33d8d8da36
tree9431ba97ee6011b7b8d17e08db60fcdfdd049fb0
parent56c1af4606f04048e3ae9ab2027a708b9684ff37
PCI: Enable ECRC only if device supports it

John reported that an Intel QuickAssist crypto accelerator didn't work in a
Dell PowerEdge R730.  The problem seems to be that we enabled ECRC when the
device doesn't support it:

  85:00.0 Co-processor [0b40]: Intel Corporation DH895XCC Series QAT [8086:0435]
    Capabilities: [100 v1] Advanced Error Reporting
      AERCap: First Error Pointer: 00, GenCap- CGenEn+ ChkCap- ChkEn+

1302fcf0d03e ("PCI: Configure *all* devices, not just hot-added ones")
exposed the problem because it applies settings from the _HPX method to all
devices, not just hot-added ones.  The R730 supplies an _HPX method that
allows the kernel to enable ECRC.

Only enable ECRC if the device advertises support for it.

Link: https://bugs.launchpad.net/ubuntu/+source/linux/+bug/1571798
Fixes: 1302fcf0d03e ("PCI: Configure *all* devices, not just hot-added ones")
Reported-by: John Mazzie <john_mazzie@dell.com>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
drivers/pci/probe.c