From b838b39e930aa1cfd099ea82ac40ed6d6413af26 Mon Sep 17 00:00:00 2001 From: Bjorn Helgaas Date: Tue, 22 Sep 2015 17:03:54 -0500 Subject: [PATCH] PCI: Clear IORESOURCE_UNSET when clipping a bridge window c770cb4cb505 ("PCI: Mark invalid BARs as unassigned") sets IORESOURCE_UNSET if we fail to claim a resource. If we tried to claim a bridge window, failed, clipped the window, and tried to claim the clipped window, we failed again because of IORESOURCE_UNSET: pci_bus 0000:00: root bus resource [mem 0xc0000000-0xffffffff window] pci 0000:00:01.0: can't claim BAR 15 [mem 0xbdf00000-0xddefffff 64bit pref]: no compatible bridge window pci 0000:00:01.0: [mem size 0x20000000 64bit pref] clipped to [mem size 0x1df00000 64bit pref] pci 0000:00:01.0: bridge window [mem size 0x1df00000 64bit pref] pci 0000:00:01.0: can't claim BAR 15 [mem size 0x1df00000 64bit pref]: no address assigned The 00:01.0 window started as [mem 0xbdf00000-0xddefffff 64bit pref]. That starts before the host bridge window [mem 0xc0000000-0xffffffff window], so we clipped the 00:01.0 window to [mem 0xc0000000-0xddefffff 64bit pref]. But we left it marked IORESOURCE_UNSET, so the second claim failed when it should have succeeded. This means downstream devices will also fail for lack of resources, e.g., in the bugzilla below, radeon 0000:01:00.0: Fatal error during GPU init Clear IORESOURCE_UNSET when we clip a bridge window. Also clear IORESOURCE_UNSET in our copy of the unclipped window so we can see exactly what the original window was and how it now fits inside the upstream window. Fixes: c770cb4cb505 ("PCI: Mark invalid BARs as unassigned") Link: https://bugzilla.kernel.org/show_bug.cgi?id=85491#c47 Based-on-patch-by: Lorenzo Pieralisi Based-on-patch-by: Yinghai Lu Tested-by: Lorenzo Pieralisi Signed-off-by: Bjorn Helgaas Reviewed-by: Lorenzo Pieralisi Acked-by: Yinghai Lu CC: stable@vger.kernel.org # v4.1+ --- drivers/pci/bus.c | 2 ++ 1 file changed, 2 insertions(+) diff --git a/drivers/pci/bus.c b/drivers/pci/bus.c index 6fbd3f2b5992..d3346d23963b 100644 --- a/drivers/pci/bus.c +++ b/drivers/pci/bus.c @@ -256,6 +256,8 @@ bool pci_bus_clip_resource(struct pci_dev *dev, int idx) res->start = start; res->end = end; + res->flags &= ~IORESOURCE_UNSET; + orig_res.flags &= ~IORESOURCE_UNSET; dev_printk(KERN_DEBUG, &dev->dev, "%pR clipped to %pR\n", &orig_res, res); -- 2.20.1