Commit ad67b437 authored May 11, 2016 by Prarit Bhargava Committed by Bjorn Helgaas May 16, 2016

PCI: Disable all BAR sizing for devices with non-compliant BARs



b84106b4 ("PCI: Disable IO/MEM decoding for devices with non-compliant
BARs") disabled BAR sizing for BARs 0-5 of devices that don't comply with
the PCI spec.  But it didn't do anything for expansion ROM BARs, so we
still try to size them, resulting in warnings like this on Broadwell-EP:

  pci 0000:ff:12.0: BAR 6: failed to assign [mem size 0x00000001 pref]

Move the non-compliant BAR check from __pci_read_base() up to
pci_read_bases() so it applies to the expansion ROM BAR as well as
to BARs 0-5.

Note that direct callers of __pci_read_base(), like sriov_init(), will now
bypass this check.  We haven't had reports of devices with broken SR-IOV
BARs yet.

[bhelgaas: changelog]
Fixes: b84106b4 ("PCI: Disable IO/MEM decoding for devices with non-compliant BARs")
Signed-off-by: Prarit Bhargava <prarit@redhat.com>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
CC: stable@vger.kernel.org
CC: Thomas Gleixner <tglx@linutronix.de>
CC: Ingo Molnar <mingo@redhat.com>
CC: "H. Peter Anvin" <hpa@zytor.com>
CC: Andi Kleen <ak@linux.intel.com>

parent da77b671

drivers/pci/probe.c

+3 −3

Original line number	Diff line number	Diff line
		@@ -179,9 +179,6 @@ int __pci_read_base(struct pci_dev *dev, enum pci_bar_type type,
		u16 orig_cmd;
		struct pci_bus_region region, inverted_region;

		if (dev->non_compliant_bars)
		return 0;

		mask = type ? PCI_ROM_ADDRESS_MASK : ~0;

		/* No printks while decoding is disabled! */
		@@ -322,6 +319,9 @@ static void pci_read_bases(struct pci_dev *dev, unsigned int howmany, int rom)
		{
		unsigned int pos, reg;

		if (dev->non_compliant_bars)
		return;

		for (pos = 0; pos < howmany; pos++) {
		struct resource *res = &dev->resource[pos];
		reg = PCI_BASE_ADDRESS_0 + (pos << 2);

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