kevin/linux
1
Fork 0
Code

PCI: Fix pci_enable_acs() support for the ACS quirks

Browse Source 
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: 47c8846a49 ("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>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
This commit is contained in:
Jason Gunthorpe 2024-10-16 20:52:33 -03:00 committed by Bjorn Helgaas
parent 9852d85ec9
commit f3c3ccc4fe
1 changed files with 9 additions and 5 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

12
drivers/pci/pci.c
View File

@ -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) static void pci_enable_acs(struct pci_dev *dev)
{ {
struct pci_acs caps; struct pci_acs caps;
bool enable_acs = false;
int pos; 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; pos = dev->acs_cap;
if (!pos) if (!pos)
return; 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); pci_read_config_word(dev, pos + PCI_ACS_CTRL, &caps.ctrl);
caps.fw_ctrl = caps.ctrl; caps.fw_ctrl = caps.ctrl;
/* If an iommu is present we start with kernel default caps */ if (enable_acs)
if (pci_acs_enable) {
if (pci_dev_specific_enable_acs(dev))
pci_std_enable_acs(dev, &caps); pci_std_enable_acs(dev, &caps);
}
/* /*
* Always apply caps from the command line, even if there is no iommu. * Always apply caps from the command line, even if there is no iommu.