Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1758599AbaJDAgQ (ORCPT ); Fri, 3 Oct 2014 20:36:16 -0400 Received: from mail.linuxfoundation.org ([140.211.169.12]:45275 "EHLO mail.linuxfoundation.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1755887AbaJCVmr (ORCPT ); Fri, 3 Oct 2014 17:42:47 -0400 From: Greg Kroah-Hartman To: linux-kernel@vger.kernel.org Cc: Greg Kroah-Hartman , stable@vger.kernel.org, Varun Sethi , Joerg Roedel Subject: [PATCH 3.16 153/357] iommu/fsl: Fix warning resulting from adding PCI device twice Date: Fri, 3 Oct 2014 14:28:59 -0700 Message-Id: <20141003212938.066534332@linuxfoundation.org> X-Mailer: git-send-email 2.1.2 In-Reply-To: <20141003212933.458851516@linuxfoundation.org> References: <20141003212933.458851516@linuxfoundation.org> User-Agent: quilt/0.63-1 MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org 3.16-stable review patch. If anyone has any objections, please let me know. ------------------ From: Varun Sethi commit 5a9137a66b521d667236e95c307b92af532fe600 upstream. iommu_group_get_for_dev determines the iommu group for the PCI device and adds the device to the group. In the PAMU driver we were again adding the device to the same group without checking if the device already had an iommu group. This resulted in the following warning. sysfs: cannot create duplicate filename '/devices/ffe200000.pcie/pci0000:00/0000:00:00.0/iommu_group' ------------[ cut here ]------------ WARNING: at fs/sysfs/dir.c:31 Modules linked in: CPU: 0 PID: 1 Comm: swapper/0 Not tainted 3.17.0-rc3-00002-g7505cea-dirty #126 task: c0000001fe0a0000 ti: c0000001fe044000 task.ti: c0000001fe044000 NIP: c00000000018879c LR: c000000000188798 CTR: c00000000001ea50 REGS: c0000001fe047040 TRAP: 0700 Not tainted (3.17.0-rc3-00002-g7505cea-dirty) MSR: 0000000080029000 CR: 24ad8e22 XER: 20000000 SOFTE: 1 GPR00: c000000000188798 c0000001fe0472c0 c0000000009a52e0 0000000000000065 GPR04: 0000000000000001 0000000000000000 3a30303a00000000 0000000027000000 GPR08: 2f696f6d00000000 c0000000008d3830 c0000000009b3938 c0000000009bb3d0 GPR12: 0000000028ad8e24 c00000000fff4000 c00000000000205c 0000000000000000 GPR16: 0000000000000000 0000000000000000 0000000000000000 0000000000000000 GPR20: 0000000000000000 0000000000000000 0000000000000000 c0000000008a4c70 GPR24: c0000000007e9010 c0000001fe0140a8 ffffffffffffffef 0000000000000001 GPR28: c0000001fe22ebb8 c0000000007e9010 c00000000090bf10 c0000001fe220000 NIP [c00000000018879c] .sysfs_warn_dup+0x74/0xa4 LR [c000000000188798] .sysfs_warn_dup+0x70/0xa4 Call Trace: [c0000001fe0472c0] [c000000000188798] .sysfs_warn_dup+0x70/0xa4 (unreliable) [c0000001fe047350] [c000000000188d34] .sysfs_do_create_link_sd.clone.2+0x168/0x174 [c0000001fe047400] [c0000000004b3cf8] .iommu_group_add_device+0x78/0x244 [c0000001fe0474b0] [c0000000004b6964] .fsl_pamu_add_device+0x88/0x1a8 [c0000001fe047570] [c0000000004b3960] .iommu_bus_notifier+0xdc/0x15c [c0000001fe047600] [c000000000059848] .notifier_call_chain+0x8c/0xe8 [c0000001fe0476a0] [c000000000059d04] .__blocking_notifier_call_chain+0x58/0x84 [c0000001fe047750] [c00000000036619c] .device_add+0x464/0x5c8 [c0000001fe047820] [c000000000300ebc] .pci_device_add+0x14c/0x17c [c0000001fe0478c0] [c000000000300fbc] .pci_scan_single_device+0xd0/0xf4 [c0000001fe047970] [c00000000030104c] .pci_scan_slot+0x6c/0x18c [c0000001fe047a10] [c00000000030226c] .pci_scan_child_bus+0x40/0x114 [c0000001fe047ac0] [c000000000021974] .pcibios_scan_phb+0x240/0x2c8 [c0000001fe047b70] [c00000000085a970] .pcibios_init+0x64/0xc8 [c0000001fe047c00] [c000000000001884] .do_one_initcall+0xbc/0x224 [c0000001fe047d00] [c000000000852d50] .kernel_init_freeable+0x14c/0x21c [c0000001fe047db0] [c000000000002078] .kernel_init+0x1c/0xfa4 [c0000001fe047e30] [c000000000000884] .ret_from_kernel_thread+0x58/0xd4 Instruction dump: 7c7f1b79 4182001c 7fe4fb78 7f83e378 38a01000 4bffc905 60000000 7c641b78 e87e8008 7fa5eb78 48482ff5 60000000 <0fe00000> 7fe3fb78 4bf7bd39 60000000 Signed-off-by: Varun Sethi Signed-off-by: Joerg Roedel Signed-off-by: Greg Kroah-Hartman --- drivers/iommu/fsl_pamu_domain.c | 10 ++++++++-- 1 file changed, 8 insertions(+), 2 deletions(-) --- a/drivers/iommu/fsl_pamu_domain.c +++ b/drivers/iommu/fsl_pamu_domain.c @@ -1048,7 +1048,7 @@ static int fsl_pamu_add_device(struct de struct iommu_group *group = ERR_PTR(-ENODEV); struct pci_dev *pdev; const u32 *prop; - int ret, len; + int ret = 0, len; /* * For platform devices we allocate a separate group for @@ -1071,7 +1071,13 @@ static int fsl_pamu_add_device(struct de if (IS_ERR(group)) return PTR_ERR(group); - ret = iommu_group_add_device(group, dev); + /* + * Check if device has already been added to an iommu group. + * Group could have already been created for a PCI device in + * the iommu_group_get_for_dev path. + */ + if (!dev->iommu_group) + ret = iommu_group_add_device(group, dev); iommu_group_put(group); return ret; -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/