PCI: Enable INTx in pci_reenable_device() only when MSI/MSI-X not enabled
authorBjorn Helgaas <bhelgaas@google.com>
Tue, 11 Mar 2014 20:22:19 +0000 (14:22 -0600)
committerBjorn Helgaas <bhelgaas@google.com>
Wed, 12 Mar 2014 17:19:18 +0000 (11:19 -0600)
commit3cdeb713dc66057b50682048c151eae07b186c42
treed9213f79303d539eee47d90f3e361f766f88f68b
parentfa389e220254c69ffae0d403eac4146171062d08
PCI: Enable INTx in pci_reenable_device() only when MSI/MSI-X not enabled

Andreas reported that after 1f42db786b14 ("PCI: Enable INTx if BIOS left
them disabled"), pciehp surprise removal stopped working.

This happens because pci_reenable_device() on the hotplug bridge (used in
the pciehp_configure_device() path) clears the Interrupt Disable bit, which
apparently breaks the bridge's MSI hotplug event reporting.

Previously we cleared the Interrupt Disable bit in do_pci_enable_device(),
which is used by both pci_enable_device() and pci_reenable_device().  But
we use pci_reenable_device() after the driver may have enabled MSI or
MSI-X, and we *set* Interrupt Disable as part of enabling MSI/MSI-X.

This patch clears Interrupt Disable only when MSI/MSI-X has not been
enabled.

Fixes: 1f42db786b14 PCI: Enable INTx if BIOS left them disabled
Link: https://bugzilla.kernel.org/show_bug.cgi?id=71691
Reported-and-tested-by: Andreas Noever <andreas.noever@gmail.com>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
CC: stable@vger.kernel.org
CC: Sarah Sharp <sarah.a.sharp@linux.intel.com>
drivers/pci/pci.c