From: Alexey Neyman Date: Wed, 9 Oct 2013 22:16:38 +0000 (-0600) Subject: x86/PCI: Coalesce multiple overlapping host bridge windows X-Git-Url: https://git.karo-electronics.de/?a=commitdiff_plain;h=3ad674d6c6c5724c83f10f422d826420c83536cd;p=linux-beck.git x86/PCI: Coalesce multiple overlapping host bridge windows Previously we coalesced windows by expanding the first overlapping one and making the second invalid. But we never look at the expanded first window again, so we fail to notice other windows that overlap it. For example, we coalesced these: [io 0x0000-0x03af] // #0 [io 0x03e0-0x0cf7] // #1 [io 0x0000-0xdfff] // #2 into these, which still overlap: [io 0x0000-0xdfff] // #0 [io 0x03e0-0x0cf7] // #1 The fix is to expand the *second* overlapping resource and ignore the first, so we get this instead with no overlaps: [io 0x0000-0xdfff] // #2 [bhelgaas: changelog] Reference: https://bugzilla.kernel.org/show_bug.cgi?id=62511 Signed-off-by: Alexey Neyman Signed-off-by: Bjorn Helgaas --- diff --git a/arch/x86/pci/acpi.c b/arch/x86/pci/acpi.c index b30e937689d6..7fb24e53d4c8 100644 --- a/arch/x86/pci/acpi.c +++ b/arch/x86/pci/acpi.c @@ -354,12 +354,12 @@ static void coalesce_windows(struct pci_root_info *info, unsigned long type) * the kernel resource tree doesn't allow overlaps. */ if (resource_overlaps(res1, res2)) { - res1->start = min(res1->start, res2->start); - res1->end = max(res1->end, res2->end); + res2->start = min(res1->start, res2->start); + res2->end = max(res1->end, res2->end); dev_info(&info->bridge->dev, "host bridge window expanded to %pR; %pR ignored\n", - res1, res2); - res2->flags = 0; + res2, res1); + res1->flags = 0; } } }