Commit f3c3ccc4 authored by Jason Gunthorpe's avatar Jason Gunthorpe Committed by Bjorn Helgaas
Browse files

PCI: Fix pci_enable_acs() support for the ACS quirks 

There are ACS quirks that hijack the normal ACS processing and deliver to
to special quirk code. The enable path needs to call
pci_dev_specific_enable_acs() and then pci_dev_specific_acs_enabled() will
report the hidden ACS state controlled by the quirk.

The recent rework got this out of order and we should try to call
pci_dev_specific_enable_acs() regardless of any actual ACS support in the
device.

As before command line parameters that effect standard PCI ACS don't
interact with the quirk versions, including the new config_acs= option.

Link: https://lore.kernel.org/r/0-v1-f96b686c625b+124-pci_acs_quirk_fix_jgg@nvidia.com


Fixes: 47c8846a ("PCI: Extend ACS configurability")
Reported-by: default avatarJiri Slaby <jirislaby@kernel.org>
Closes: https://lore.kernel.org/all/e89107da-ac99-4d3a-9527-a4df9986e120@kernel.org
Closes: https://bugzilla.suse.com/show_bug.cgi?id=1229019


Tested-by: default avatarSteffen Dirkwinkel <me@steffen.cc>
Signed-off-by: default avatarJason Gunthorpe <jgg@nvidia.com>
Signed-off-by: default avatarBjorn Helgaas <bhelgaas@google.com>
parent 9852d85e

drivers/pci/pci.c

+9 −5
Original line number Diff line number Diff line
@@ -1067,8 +1067,15 @@ static void pci_std_enable_acs(struct pci_dev *dev, struct pci_acs *caps) 
static void pci_enable_acs(struct pci_dev *dev)

{

	struct pci_acs caps;

	bool enable_acs = false;

	int pos;



	/* If an iommu is present we start with kernel default caps */

	if (pci_acs_enable) {

		if (pci_dev_specific_enable_acs(dev))

			enable_acs = true;

	}



	pos = dev->acs_cap;

	if (!pos)

		return;
@@ -1077,11 +1084,8 @@ static void pci_enable_acs(struct pci_dev *dev) 
	pci_read_config_word(dev, pos + PCI_ACS_CTRL, &caps.ctrl);

	caps.fw_ctrl = caps.ctrl;



	/* If an iommu is present we start with kernel default caps */

	if (pci_acs_enable) {

		if (pci_dev_specific_enable_acs(dev))

	if (enable_acs)

		pci_std_enable_acs(dev, &caps);

	}



	/*

	 * Always apply caps from the command line, even if there is no iommu.