Hi Adrian, On 2/11/22 10:45 AM, Adrian Huang wrote:
From: Adrian Huang<ahuan...@lenovo.com>When enabling VMD and IOMMU scalable mode, the following kernel panic call trace/kernel log is shown in Eagle Stream platform (Sapphire Rapids CPU) during booting: pci 0000:59:00.5: Adding to iommu group 42 ... vmd 0000:59:00.5: PCI host bridge to bus 10000:80 pci 10000:80:01.0: [8086:352a] type 01 class 0x060400 pci 10000:80:01.0: reg 0x10: [mem 0x00000000-0x0001ffff 64bit] pci 10000:80:01.0: enabling Extended Tags pci 10000:80:01.0: PME# supported from D0 D3hot D3cold pci 10000:80:01.0: DMAR: Setup RID2PASID failed pci 10000:80:01.0: Failed to add to iommu group 42: -16 pci 10000:80:03.0: [8086:352b] type 01 class 0x060400 pci 10000:80:03.0: reg 0x10: [mem 0x00000000-0x0001ffff 64bit] pci 10000:80:03.0: enabling Extended Tags pci 10000:80:03.0: PME# supported from D0 D3hot D3cold list_add double add: new=ff4d61160b74b8a0, prev=ff4d611d8e245c10, next=ff4d61160b74b8a0. ------------[ cut here ]------------ kernel BUG at lib/list_debug.c:29! invalid opcode: 0000 [#1] PREEMPT SMP NOPTI CPU: 0 PID: 7 Comm: kworker/0:1 Not tainted 5.17.0-rc3+ #7 Hardware name: Lenovo ThinkSystem SR650V3/SB27A86647, BIOS ESE101Y-1.00 01/13/2022 Workqueue: events work_for_cpu_fn RIP: 0010:__list_add_valid.cold+0x26/0x3f Code: 9a 4a ab ff 4c 89 c1 48 c7 c7 40 0c d9 9e e8 b9 b1 fe ff 0f 0b 48 89 f2 4c 89 c1 48 89 fe 48 c7 c7 f0 0c d9 9e e8 a2 b1 fe ff <0f> 0b 48 89 d1 4c 89 c6 4c 89 ca 48 c7 c7 98 0c d9 9e e8 8b b1 fe RSP: 0000:ff5ad434865b3a40 EFLAGS: 00010246 RAX: 0000000000000058 RBX: ff4d61160b74b880 RCX: ff4d61255e1fffa8 RDX: 0000000000000000 RSI: 00000000fffeffff RDI: ffffffff9fd34f20 RBP: ff4d611d8e245c00 R08: 0000000000000000 R09: ff5ad434865b3888 R10: ff5ad434865b3880 R11: ff4d61257fdc6fe8 R12: ff4d61160b74b8a0 R13: ff4d61160b74b8a0 R14: ff4d611d8e245c10 R15: ff4d611d8001ba70 FS: 0000000000000000(0000) GS:ff4d611d5ea00000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: ff4d611fa1401000 CR3: 0000000aa0210001 CR4: 0000000000771ef0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe07f0 DR7: 0000000000000400 PKRU: 55555554 Call Trace: <TASK> intel_pasid_alloc_table+0x9c/0x1d0 dmar_insert_one_dev_info+0x423/0x540 ? device_to_iommu+0x12d/0x2f0 intel_iommu_attach_device+0x116/0x290 __iommu_attach_device+0x1a/0x90 iommu_group_add_device+0x190/0x2c0 __iommu_probe_device+0x13e/0x250 iommu_probe_device+0x24/0x150 iommu_bus_notifier+0x69/0x90 blocking_notifier_call_chain+0x5a/0x80 device_add+0x3db/0x7b0 ? arch_memremap_can_ram_remap+0x19/0x50 ? memremap+0x75/0x140 pci_device_add+0x193/0x1d0 pci_scan_single_device+0xb9/0xf0 pci_scan_slot+0x4c/0x110 pci_scan_child_bus_extend+0x3a/0x290 vmd_enable_domain.constprop.0+0x63e/0x820 vmd_probe+0x163/0x190 local_pci_probe+0x42/0x80 work_for_cpu_fn+0x13/0x20 process_one_work+0x1e2/0x3b0 worker_thread+0x1c4/0x3a0 ? rescuer_thread+0x370/0x370 kthread+0xc7/0xf0 ? kthread_complete_and_exit+0x20/0x20 ret_from_fork+0x1f/0x30 </TASK> Modules linked in: ---[ end trace 0000000000000000 ]--- ... Kernel panic - not syncing: Fatal exception Kernel Offset: 0x1ca00000 from 0xffffffff81000000 (relocation range: 0xffffffff80000000-0xffffffffbfffffff) ---[ end Kernel panic - not syncing: Fatal exception ]--- The following 'lspci' output shows devices '10000:80:*' are subdevices of the VMD device 0000:59:00.5: $ lspci ... 0000:59:00.5 RAID bus controller: Intel Corporation Volume Management Device NVMe RAID Controller (rev 20) ... 10000:80:01.0 PCI bridge: Intel Corporation Device 352a (rev 03) 10000:80:03.0 PCI bridge: Intel Corporation Device 352b (rev 03) 10000:80:05.0 PCI bridge: Intel Corporation Device 352c (rev 03) 10000:80:07.0 PCI bridge: Intel Corporation Device 352d (rev 03) 10000:81:00.0 Non-Volatile memory controller: Intel Corporation NVMe Datacenter SSD [3DNAND, Beta Rock Controller] 10000:82:00.0 Non-Volatile memory controller: Intel Corporation NVMe Datacenter SSD [3DNAND, Beta Rock Controller] The symptom 'list_add double add' is caused by the following failure message: pci 10000:80:01.0: DMAR: Setup RID2PASID failed pci 10000:80:01.0: Failed to add to iommu group 42: -16 pci 10000:80:03.0: [8086:352b] type 01 class 0x060400 Device 10000:80:01.0 is the subdevice of the VMD device 0000:59:00.5, so invoking intel_pasid_alloc_table() gets the pasid_table of the VMD device 0000:59:00.5. Here is call path: intel_pasid_alloc_table pci_for_each_dma_alias get_alias_pasid_table search_pasid_table pci_real_dma_dev() in pci_for_each_dma_alias() gets the real dma device which is the VMD device 0000:59:00.5. However, pte of the VMD device 0000:59:00.5 has been configured during this message "pci 0000:59:00.5: Adding to iommu group 42". So, the status -EBUSY is returned when configuring pasid entry for device 10000:80:01.0. It then invokes dmar_remove_one_dev_info() to release 'struct device_domain_info *' from iommu_devinfo_cache. But, the pasid table is not released because of the following statement in __dmar_remove_one_dev_info(): if (info->dev && !dev_is_real_dma_subdevice(info->dev)) { ... intel_pasid_free_table(info->dev); } The subsequent dmar_insert_one_dev_info() operation of device 10000:80:03.0 allocates 'struct device_domain_info *' from iommu_devinfo_cache. The allocated address is the same address that is released previously for device 10000:80:01.0. Finally, invoking device_attach_pasid_table() causes the issue. The solution is to prevent from allocating pasid table if those devices are subdevices of the VMD device.
Thanks for your patch! Is this the only patch that is needed to make VMD devices work in VT-d scalable mode? Best regards, baolu _______________________________________________ iommu mailing list iommu@lists.linux-foundation.org https://lists.linuxfoundation.org/mailman/listinfo/iommu
