diff mbox series

[rc] PCI: Fix pci_enable_acs() support for the ACS quirks

Message ID 0-v1-f96b686c625b+124-pci_acs_quirk_fix_jgg@nvidia.com (mailing list archive)
State New
Headers show
Series [rc] PCI: Fix pci_enable_acs() support for the ACS quirks | expand

Commit Message

Jason Gunthorpe Oct. 16, 2024, 11:52 p.m. UTC 
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.

Fixes: 47c8846a49ba ("PCI: Extend ACS configurability")
Reported-by: Jiri 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: Steffen Dirkwinkel <me@steffen.cc>
Signed-off-by: Jason Gunthorpe <jgg@nvidia.com>
---
 drivers/pci/pci.c | 14 +++++++++-----
 1 file changed, 9 insertions(+), 5 deletions(-)


base-commit: dc5006cfcf62bea88076a587344ba5e00e66d1c6
diff mbox series

Patch

diff --git a/drivers/pci/pci.c b/drivers/pci/pci.c
index 7d85c04fbba2ae..225a6cd2e9ca3b 100644
--- a/drivers/pci/pci.c
+++ b/drivers/pci/pci.c
@@ -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))
-			pci_std_enable_acs(dev, &caps);
-	}
+	if (enable_acs)
+		pci_std_enable_acs(dev, &caps);
 
 	/*
 	 * Always apply caps from the command line, even if there is no iommu.