From mboxrd@z Thu Jan 1 00:00:00 1970 From: jglauber@cavium.com (Jan Glauber) Date: Fri, 8 Sep 2017 10:10:33 +0200 Subject: [PATCH v4 3/3] PCI: Avoid slot reset if bus reset is not possible In-Reply-To: <20170908081033.3025-1-jglauber@cavium.com> References: <20170908081033.3025-1-jglauber@cavium.com> Message-ID: <20170908081033.3025-4-jglauber@cavium.com> To: linux-arm-kernel@lists.infradead.org List-Id: linux-arm-kernel.lists.infradead.org When checking to see if a PCI slot can safely be reset, we check to see if any of the children have their PCI_DEV_FLAGS_NO_BUS_RESET flag set. Some PCIe root port bridges do not behave well after a slot reset, and may cause the device in the slot to become unusable. Add a check for the PCI_DEV_FLAGS_NO_BUS_RESET flag being set in the bridge device to prevent the slot from being reset. Signed-off-by: Jan Glauber --- drivers/pci/pci.c | 4 ++++ 1 file changed, 4 insertions(+) diff --git a/drivers/pci/pci.c b/drivers/pci/pci.c index b2a46ca7f133..45a086fc3592 100644 --- a/drivers/pci/pci.c +++ b/drivers/pci/pci.c @@ -4393,6 +4393,10 @@ static bool pci_slot_resetable(struct pci_slot *slot) { struct pci_dev *dev; + if (slot->bus->self && + (slot->bus->self->dev_flags & PCI_DEV_FLAGS_NO_BUS_RESET)) + return false; + list_for_each_entry(dev, &slot->bus->devices, bus_list) { if (!dev->slot || dev->slot != slot) continue; -- 2.9.0.rc0.21.g7777322