From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: From: Greg Kroah-Hartman To: linux-kernel@vger.kernel.org Cc: Greg Kroah-Hartman , stable@vger.kernel.org, Lorenzo Pieralisi , Bjorn Helgaas , Yinghai Lu Subject: [PATCH 4.2 109/258] PCI: Clear IORESOURCE_UNSET when clipping a bridge window Date: Sat, 17 Oct 2015 18:57:02 -0700 Message-Id: <20151018014735.344552242@linuxfoundation.org> In-Reply-To: <20151018014729.976101177@linuxfoundation.org> References: <20151018014729.976101177@linuxfoundation.org> MIME-Version: 1.0 Content-Type: text/plain; charset=ISO-8859-15 Sender: linux-kernel-owner@vger.kernel.org List-ID: 4.2-stable review patch. If anyone has any objections, please let me know. ------------------ From: Bjorn Helgaas commit b838b39e930aa1cfd099ea82ac40ed6d6413af26 upstream. 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 Signed-off-by: Greg Kroah-Hartman --- drivers/pci/bus.c | 2 ++ 1 file changed, 2 insertions(+) --- a/drivers/pci/bus.c +++ b/drivers/pci/bus.c @@ -256,6 +256,8 @@ bool pci_bus_clip_resource(struct pci_de 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);