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PCI: Fix pci_enable_acs() support for the ACS quirks

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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
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14
drivers/pci/pci.c
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@ -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.