Data structure drhd->iommu is shared between DMA remapping driver and interrupt remapping driver, so DMA remapping driver shouldn't release drhd->iommu when it failed to initialize IOMMU devices. Otherwise it may cause invalid memory access to the interrupt remapping driver. Sample stack dump: [ 13.315090] BUG: unable to handle kernel paging request at ffffc9000605a088 [ 13.323221] IP: [<ffffffff81461bac>] qi_submit_sync+0x15c/0x400 [ 13.330107] PGD 82f81e067 PUD c2f81e067 PMD 82e846067 PTE 0 [ 13.336818] Oops: 0002 [#1] SMP [ 13.340757] Modules linked in: [ 13.344422] CPU: 0 PID: 4 Comm: kworker/0:0 Not tainted 3.13.0-rc1-gerry+ #7 [ 13.352474] Hardware name: Intel Corporation LH Pass ........../SVRBD-ROW_T, BIOS SE5C600.86B.99.99.x059.091020121352 09/10/2012 [ 13.365659] Workqueue: events work_for_cpu_fn [ 13.370774] task: ffff88042ddf00d0 ti: ffff88042ddee000 task.ti: ffff88042dde e000 [ 13.379389] RIP: 0010:[<ffffffff81461bac>] [<ffffffff81461bac>] qi_submit_sy nc+0x15c/0x400 [ 13.389055] RSP: 0000:ffff88042ddef940 EFLAGS: 00010002 [ 13.395151] RAX: 00000000000005e0 RBX: 0000000000000082 RCX: 0000000200000025 [ 13.403308] RDX: ffffc9000605a000 RSI: 0000000000000010 RDI: ffff88042ddb8610 [ 13.411446] RBP: ffff88042ddef9a0 R08: 00000000000005d0 R09: 0000000000000001 [ 13.419599] R10: 0000000000000000 R11: 000000000000005d R12: 000000000000005c [ 13.427742] R13: ffff88102d84d300 R14: 0000000000000174 R15: ffff88042ddb4800 [ 13.435877] FS: 0000000000000000(0000) GS:ffff88043de00000(0000) knlGS:00000 00000000000 [ 13.445168] CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 [ 13.451749] CR2: ffffc9000605a088 CR3: 0000000001a0b000 CR4: 00000000000407f0 [ 13.459895] Stack: [ 13.462297] ffff88042ddb85d0 000000000000005d ffff88042ddef9b0 0000000000000 5d0 [ 13.471147] 00000000000005c0 ffff88042ddb8000 000000000000005c 0000000000000 015 [ 13.480001] ffff88042ddb4800 0000000000000282 ffff88042ddefa40 ffff88042ddef ac0 [ 13.488855] Call Trace: [ 13.491771] [<ffffffff8146848d>] modify_irte+0x9d/0xd0 [ 13.497778] [<ffffffff8146886d>] intel_setup_ioapic_entry+0x10d/0x290 [ 13.505250] [<ffffffff810a92a6>] ? trace_hardirqs_on_caller+0x16/0x1e0 [ 13.512824] [<ffffffff810346b0>] ? default_init_apic_ldr+0x60/0x60 [ 13.519998] [<ffffffff81468be0>] setup_ioapic_remapped_entry+0x20/0x30 [ 13.527566] [<ffffffff8103683a>] io_apic_setup_irq_pin+0x12a/0x2c0 [ 13.534742] [<ffffffff8136673b>] ? acpi_pci_irq_find_prt_entry+0x2b9/0x2d8 [ 13.544102] [<ffffffff81037fd5>] io_apic_setup_irq_pin_once+0x85/0xa0 [ 13.551568] [<ffffffff8103816f>] ? mp_find_ioapic_pin+0x8f/0xf0 [ 13.558434] [<ffffffff81038044>] io_apic_set_pci_routing+0x34/0x70 [ 13.565621] [<ffffffff8102f4cf>] mp_register_gsi+0xaf/0x1c0 [ 13.572111] [<ffffffff8102f5ee>] acpi_register_gsi_ioapic+0xe/0x10 [ 13.579286] [<ffffffff8102f33f>] acpi_register_gsi+0xf/0x20 [ 13.585779] [<ffffffff81366b86>] acpi_pci_irq_enable+0x171/0x1e3 [ 13.592764] [<ffffffff8146d771>] pcibios_enable_device+0x31/0x40 [ 13.599744] [<ffffffff81320e9b>] do_pci_enable_device+0x3b/0x60 [ 13.606633] [<ffffffff81322248>] pci_enable_device_flags+0xc8/0x120 [ 13.613887] [<ffffffff813222f3>] pci_enable_device+0x13/0x20 [ 13.620484] [<ffffffff8132fa7e>] pcie_port_device_register+0x1e/0x510 [ 13.627947] [<ffffffff810a92a6>] ? trace_hardirqs_on_caller+0x16/0x1e0 [ 13.635510] [<ffffffff810a947d>] ? trace_hardirqs_on+0xd/0x10 [ 13.642189] [<ffffffff813302b8>] pcie_portdrv_probe+0x58/0xc0 [ 13.648877] [<ffffffff81323ba5>] local_pci_probe+0x45/0xa0 [ 13.655266] [<ffffffff8106bc44>] work_for_cpu_fn+0x14/0x20 [ 13.661656] [<ffffffff8106fa79>] process_one_work+0x369/0x710 [ 13.668334] [<ffffffff8106fa02>] ? process_one_work+0x2f2/0x710 [ 13.675215] [<ffffffff81071d56>] ? worker_thread+0x46/0x690 [ 13.681714] [<ffffffff81072194>] worker_thread+0x484/0x690 [ 13.688109] [<ffffffff81071d10>] ? cancel_delayed_work_sync+0x20/0x20 [ 13.695576] [<ffffffff81079c60>] kthread+0xf0/0x110 [ 13.701300] [<ffffffff8108e7bf>] ? local_clock+0x3f/0x50 [ 13.707492] [<ffffffff81079b70>] ? kthread_create_on_node+0x250/0x250 [ 13.714959] [<ffffffff81574d2c>] ret_from_fork+0x7c/0xb0 [ 13.721152] [<ffffffff81079b70>] ? kthread_create_on_node+0x250/0x250 Signed-off-by: Jiang Liu <jiang.liu@xxxxxxxxxxxxxxx> --- drivers/iommu/dmar.c | 56 ++++++++++++++++++++++++++++------------- drivers/iommu/intel-iommu.c | 13 +++------- include/linux/dma_remapping.h | 4 --- include/linux/intel-iommu.h | 1 - 4 files changed, 43 insertions(+), 31 deletions(-) diff --git a/drivers/iommu/dmar.c b/drivers/iommu/dmar.c index 7ecc7b8..302e037 100644 --- a/drivers/iommu/dmar.c +++ b/drivers/iommu/dmar.c @@ -53,6 +53,7 @@ struct acpi_table_header * __initdata dmar_tbl; static acpi_size dmar_tbl_size; static int alloc_iommu(struct dmar_drhd_unit *drhd); +static void free_iommu(struct intel_iommu *iommu); static void __init dmar_register_drhd_unit(struct dmar_drhd_unit *drhd) { @@ -205,25 +206,28 @@ dmar_parse_one_drhd(struct acpi_dmar_header *header) return 0; } +static void dmar_free_drhd(struct dmar_drhd_unit *dmaru) +{ + if (dmaru->devices && dmaru->devices_cnt) + dmar_free_dev_scope(&dmaru->devices, &dmaru->devices_cnt); + if (dmaru->iommu) + free_iommu(dmaru->iommu); + kfree(dmaru); +} + static int __init dmar_parse_dev(struct dmar_drhd_unit *dmaru) { struct acpi_dmar_hardware_unit *drhd; - int ret = 0; drhd = (struct acpi_dmar_hardware_unit *) dmaru->hdr; if (dmaru->include_all) return 0; - ret = dmar_parse_dev_scope((void *)(drhd + 1), - ((void *)drhd) + drhd->header.length, - &dmaru->devices_cnt, &dmaru->devices, - drhd->segment); - if (ret) { - list_del(&dmaru->list); - kfree(dmaru); - } - return ret; + return dmar_parse_dev_scope((void *)(drhd + 1), + ((void *)drhd) + drhd->header.length, + &dmaru->devices_cnt, &dmaru->devices, + drhd->segment); } #ifdef CONFIG_ACPI_NUMA @@ -435,7 +439,7 @@ dmar_find_matched_drhd_unit(struct pci_dev *dev) int __init dmar_dev_scope_init(void) { static int dmar_dev_scope_initialized; - struct dmar_drhd_unit *drhd, *drhd_n; + struct dmar_drhd_unit *drhd; int ret = -ENODEV; if (dmar_dev_scope_initialized) @@ -444,7 +448,7 @@ int __init dmar_dev_scope_init(void) if (list_empty(&dmar_drhd_units)) goto fail; - list_for_each_entry_safe(drhd, drhd_n, &dmar_drhd_units, list) { + list_for_each_entry(drhd, &dmar_drhd_units, list) { ret = dmar_parse_dev(drhd); if (ret) goto fail; @@ -725,12 +729,13 @@ static int alloc_iommu(struct dmar_drhd_unit *drhd) return err; } -void free_iommu(struct intel_iommu *iommu) +static void free_iommu(struct intel_iommu *iommu) { - if (!iommu) - return; - - free_dmar_iommu(iommu); + if (iommu->irq) { + free_irq(iommu->irq, iommu); + irq_set_handler_data(iommu->irq, NULL); + destroy_irq(iommu->irq); + } if (iommu->reg) unmap_iommu(iommu); @@ -1368,4 +1373,21 @@ int __init dmar_ir_support(void) return dmar->flags & 0x1; } +static int __init dmar_free_unused_resources(void) +{ + struct dmar_drhd_unit *dmaru, *dmaru_n; + + /* DMAR units are in use */ + if (irq_remapping_enabled || intel_iommu_enabled) + return 0; + + list_for_each_entry_safe(dmaru, dmaru_n, &dmar_drhd_units, list) { + list_del(&dmaru->list); + dmar_free_drhd(dmaru); + } + + return 0; +} + +late_initcall(dmar_free_unused_resources); IOMMU_INIT_POST(detect_intel_iommu); diff --git a/drivers/iommu/intel-iommu.c b/drivers/iommu/intel-iommu.c index ee536ad..60fa821 100644 --- a/drivers/iommu/intel-iommu.c +++ b/drivers/iommu/intel-iommu.c @@ -1265,7 +1265,7 @@ static int iommu_init_domains(struct intel_iommu *iommu) static void domain_exit(struct dmar_domain *domain); static void vm_domain_exit(struct dmar_domain *domain); -void free_dmar_iommu(struct intel_iommu *iommu) +static void free_dmar_iommu(struct intel_iommu *iommu) { struct dmar_domain *domain; int i; @@ -1290,15 +1290,10 @@ void free_dmar_iommu(struct intel_iommu *iommu) if (iommu->gcmd & DMA_GCMD_TE) iommu_disable_translation(iommu); - if (iommu->irq) { - /* This will mask the irq */ - free_irq(iommu->irq, iommu); - irq_set_handler_data(iommu->irq, NULL); - destroy_irq(iommu->irq); - } - kfree(iommu->domains); kfree(iommu->domain_ids); + iommu->domains = NULL; + iommu->domain_ids = NULL; g_iommus[iommu->seq_id] = NULL; @@ -2627,7 +2622,7 @@ static int __init init_dmars(void) return 0; error: for_each_active_iommu(iommu, drhd) - free_iommu(iommu); + free_dmar_iommu(iommu); kfree(g_iommus); return ret; } diff --git a/include/linux/dma_remapping.h b/include/linux/dma_remapping.h index 57c9a8a..7ac17f5 100644 --- a/include/linux/dma_remapping.h +++ b/include/linux/dma_remapping.h @@ -27,7 +27,6 @@ struct root_entry; #ifdef CONFIG_INTEL_IOMMU -extern void free_dmar_iommu(struct intel_iommu *iommu); extern int iommu_calculate_agaw(struct intel_iommu *iommu); extern int iommu_calculate_max_sagaw(struct intel_iommu *iommu); extern int dmar_disabled; @@ -41,9 +40,6 @@ static inline int iommu_calculate_max_sagaw(struct intel_iommu *iommu) { return 0; } -static inline void free_dmar_iommu(struct intel_iommu *iommu) -{ -} #define dmar_disabled (1) #define intel_iommu_enabled (0) #endif diff --git a/include/linux/intel-iommu.h b/include/linux/intel-iommu.h index f2c4114..2c4bed5 100644 --- a/include/linux/intel-iommu.h +++ b/include/linux/intel-iommu.h @@ -348,7 +348,6 @@ static inline void __iommu_flush_cache( extern struct dmar_drhd_unit * dmar_find_matched_drhd_unit(struct pci_dev *dev); extern int dmar_find_matched_atsr_unit(struct pci_dev *dev); -extern void free_iommu(struct intel_iommu *iommu); extern int dmar_enable_qi(struct intel_iommu *iommu); extern void dmar_disable_qi(struct intel_iommu *iommu); extern int dmar_reenable_qi(struct intel_iommu *iommu); -- 1.7.10.4 -- To unsubscribe from this list: send the line "unsubscribe linux-pci" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html