Hi, On 12/27/19 7:56 AM, Patrick Steinhardt wrote:
Starting with commit fa212a97f3a3 ("iommu/vt-d: Probe DMA-capable ACPI name space devices"), we now probe DMA-capable ACPI name space devices. On Dell XPS 13 9343, which has an Intel LPSS platform device INTL9C60 enumerated via ACPI, this change leads to the following warning:------------[ cut here ]------------ WARNING: CPU: 1 PID: 1 at pci_device_group+0x11a/0x130 CPU: 1 PID: 1 Comm: swapper/0 Tainted: G T 5.5.0-rc3+ #22 Hardware name: Dell Inc. XPS 13 9343/0310JH, BIOS A20 06/06/2019 RIP: 0010:pci_device_group+0x11a/0x130 Code: f0 ff ff 48 85 c0 49 89 c4 75 c4 48 8d 74 24 10 48 89 ef e8 48 ef ff ff 48 85 c0 49 89 c4 75 af e8 db f7 ff ff 49 89 c4 eb a5 <0f> 0b 49 c7 c4 ea ff ff ff eb 9a e8 96 1e c7 ff 66 0f 1f 44 00 00 RSP: 0000:ffffc0d6c0043cb0 EFLAGS: 00010202 RAX: 0000000000000000 RBX: ffffa3d1d43dd810 RCX: 0000000000000000 RDX: ffffa3d1d4fecf80 RSI: ffffa3d12943dcc0 RDI: ffffa3d1d43dd810 RBP: ffffa3d1d43dd810 R08: 0000000000000000 R09: ffffa3d1d4c04a80 R10: ffffa3d1d4c00880 R11: ffffa3d1d44ba000 R12: 0000000000000000 R13: ffffa3d1d4383b80 R14: ffffa3d1d4c090d0 R15: ffffa3d1d4324530 FS: 0000000000000000(0000) GS:ffffa3d1d6700000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 0000000000000000 CR3: 000000000460a001 CR4: 00000000003606e0 Call Trace: ? iommu_group_get_for_dev+0x81/0x1f0 ? intel_iommu_add_device+0x61/0x170 ? iommu_probe_device+0x43/0xd0 ? intel_iommu_init+0x1fa2/0x2235 ? pci_iommu_init+0x52/0xe7 ? e820__memblock_setup+0x15c/0x15c ? do_one_initcall+0xcc/0x27e ? kernel_init_freeable+0x169/0x259 ? rest_init+0x95/0x95 ? kernel_init+0x5/0xeb ? ret_from_fork+0x35/0x40 ---[ end trace 28473e7abc25b92c ]--- DMAR: ACPI name space devices didn't probe correctly The bug results from the fact that while we now enumerate ACPI devices, we aren't able to handle any non-PCI device when generating the device group. Fix the issue by implementing an Intel-specific callback that returns `pci_device_group` only if the device is a PCI device. Otherwise, it will return a generic device group. Fixes: fa212a97f3a3 ("iommu/vt-d: Probe DMA-capable ACPI name space devices") Signed-off-by: Patrick Steinhardt<p...@pks.im>
This will allocate per-device group for the ANDD device. Different devices that couldn't be isolated should be put in a single group. Unfortunately, the spec doesn't state how the ANDD devices are isolated. Currently we don't support assigning a platform device to user level as far as I can see, so though this fix is not the best, it won't break anything. I will ack this fix so that the kernel crash could be fixed before we figure out a better solution. Cc: sta...@vger.kernel.org # v5.3+ Acked-by: Lu Baolu <baolu...@linux.intel.com> Best regards, -baolu _______________________________________________ iommu mailing list iommu@lists.linux-foundation.org https://lists.linuxfoundation.org/mailman/listinfo/iommu
