From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from szxga02-in.huawei.com ([119.145.14.65]:16947 "EHLO szxga02-in.huawei.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1760241AbbA1Bxn (ORCPT ); Tue, 27 Jan 2015 20:53:43 -0500 From: Yijing Wang To: CC: , , Yijing Wang Subject: [PATCH v2] PCI: Add guard to avoid mapping a invalid msix base address Date: Wed, 28 Jan 2015 09:52:17 +0800 Message-ID: <1422409937-1875-1-git-send-email-wangyijing@huawei.com> MIME-Version: 1.0 Content-Type: text/plain Sender: linux-pci-owner@vger.kernel.org List-ID: Sometimes, a pci bridge device BAR was not assigned properly. After we call pci_bus_assign_resources(), the resource of the BAR would be reseted. So if we try to enable msix for this device, it will map a invalid resource as the msix base address, and a warning call trace will report. pci_bus_assign_resources() __pci_bus_assign_resources() pbus_assign_resources_sorted() __assign_resources_sorted() assign_requested_resources_sorted() pci_assign_resource() -->fail reset_resource() -->res->start/end/flags = 0 pcie_port_device_register() init_service_irqs() pcie_port_enable_msix() ... msix_capability_init() msix_map_region() phys_addr = pci_resource_start(dev, bir) + table_offset; If BAR(index=bir) was not assign properly, pci_resource_start(dev, bir) here would return 0, so phys_addr is a invalid physical address of msix. [ 43.094087] ------------[ cut here ]------------ [ 43.097418] WARNING: CPU: 1 PID: 1800 at arch/arm64/mm/ioremap.c:58 __ioremap_caller+0xd4/0xe8() ... [ 43.121694] CPU: 1 PID: 1800 Comm: insmod Tainted: G O 3.16.0 #5 [ 43.127374] Call trace: [ 43.128522] [] dump_backtrace+0x0/0x130 [ 43.132637] [] show_stack+0x10/0x1c [ 43.136402] [] dump_stack+0x74/0x94 [ 43.140166] [] warn_slowpath_common+0x8c/0xb4 [ 43.144804] [] warn_slowpath_null+0x14/0x20 [ 43.149266] [] __ioremap_caller+0xd0/0xe8 [ 43.153555] [] __ioremap+0xc/0x18 [ 43.157145] [] pci_enable_msix+0x238/0x44c [ 43.161521] [] pci_enable_msix_range+0x34/0x80 [ 43.166243] [] pcie_port_device_register+0x104/0x480 [ 43.171491] [] pcie_portdrv_probe+0x38/0xa0 [ 43.175952] [] pci_device_probe+0x78/0xd4 [ 43.180238] [] really_probe+0x6c/0x22c [ 43.184265] [] __device_attach+0x5c/0x6c [ 43.188466] [] bus_for_each_drv+0x50/0x94 [ 43.192755] [] device_attach+0x9c/0xc0 [ 43.196780] [] pci_bus_add_device+0x38/0x80 [ 43.201243] [] pci_bus_add_devices+0x4c/0xd4 [ 43.205791] [] pci_common_init+0x274/0x378 [ 43.210170] [] $x+0xb8c/0xc88 [pcie] [ 43.214024] [] platform_drv_probe+0x20/0x58 [ 43.218483] [] really_probe+0xc4/0x22c [ 43.222510] [] __driver_attach+0xa0/0xa8 [ 43.226708] [] bus_for_each_dev+0x54/0x98 [ 43.231000] [] driver_attach+0x1c/0x28 [ 43.235024] [] bus_add_driver+0x14c/0x204 [ 43.239309] [] driver_register+0x64/0x130 [ 43.243598] [] __platform_driver_register+0x5c/0x68 [ 43.248757] [] platform_driver_probe+0x28/0xac [ 43.253485] [] pcie_init+0x30/0x3c [pcie] [ 43.258293] [] do_one_initcall+0x88/0x19c [ 43.262585] [] load_module+0xc2c/0xf2c [ 43.266609] [] SyS_finit_module+0x78/0x88 [ 43.270897] ---[ end trace ea5eb60837afb5aa ]--- Reported-by: Zhang Jukuo Tested-by: Zhang Jukuo Signed-off-by: Yijing Wang --- drivers/pci/msi.c | 5 +++++ 1 files changed, 5 insertions(+), 0 deletions(-) diff --git a/drivers/pci/msi.c b/drivers/pci/msi.c index fd60806..c3e7dfc 100644 --- a/drivers/pci/msi.c +++ b/drivers/pci/msi.c @@ -694,11 +694,16 @@ static void __iomem *msix_map_region(struct pci_dev *dev, unsigned nr_entries) { resource_size_t phys_addr; u32 table_offset; + unsigned long flags; u8 bir; pci_read_config_dword(dev, dev->msix_cap + PCI_MSIX_TABLE, &table_offset); bir = (u8)(table_offset & PCI_MSIX_TABLE_BIR); + flags = pci_resource_flags(dev, bir); + if (!flags || (flags & IORESOURCE_UNSET)) + return NULL; + table_offset &= PCI_MSIX_TABLE_OFFSET; phys_addr = pci_resource_start(dev, bir) + table_offset; -- 1.7.1