Hi! I've been using KVM PCI passthrough with a dual-port NIC for over a year. I just upgraded to v4.3 from v4.1.4 and PCI passthrough stopped working. I checked with v4.1.9 and it still works there. Version 4.2 seems to point after which my system doesn't work. How can I help to narrow down the cause of the problem? I checked the intel-iommu.c and there seem to have been lots of changes between 4.1.9 and 4.2 in drivers/iommu/intel-iommu.c. My motherboard is Asus P8C WS which has Intel C216 chipset. CPU is Intel I5-3470. From v4.2 onwards passthrough fails with:
pci-stub 0000:02:00.0: kvm assign device failed ret -22. This is grep from dmesg. First is non-working v4.2 then working v4.1.9: Nov 12 23:14:06 base kernel: Linux version 4.2.0 (root@base) (gcc version 4.8.3 20140911 (Red Hat 4.8.3-9) (GCC) ) #1 SMP Thu Nov 12 23:04:04 EET 2015 Nov 12 23:14:06 base kernel: ACPI: DMAR 0x00000000DA99F4A8 0000B8 (v01 INTEL SNB 00000001 INTL 00000001) Nov 12 23:14:06 base kernel: DMAR: Host address width 36 Nov 12 23:14:06 base kernel: DMAR: DRHD base: 0x000000fed90000 flags: 0x0 Nov 12 23:14:06 base kernel: DMAR: dmar0: reg_base_addr fed90000 ver 1:0 cap c0000020e60262 ecap f0101a Nov 12 23:14:06 base kernel: DMAR: DRHD base: 0x000000fed91000 flags: 0x1 Nov 12 23:14:06 base kernel: DMAR: dmar1: reg_base_addr fed91000 ver 1:0 cap c9008020660262 ecap f010da Nov 12 23:14:06 base kernel: DMAR: RMRR base: 0x000000da911000 end: 0x000000da922fff Nov 12 23:14:06 base kernel: DMAR: RMRR base: 0x000000dd000000 end: 0x000000df1fffff Nov 12 23:14:06 base kernel: DMAR-IR: IOAPIC id 2 under DRHD base 0xfed91000 IOMMU 1 Nov 12 23:14:06 base kernel: DMAR-IR: HPET id 0 under DRHD base 0xfed91000 Nov 12 23:14:06 base kernel: DMAR-IR: Enabled IRQ remapping in xapic mode Nov 12 23:14:06 base kernel: DMAR: No ATSR found Nov 12 23:14:06 base kernel: DMAR: dmar0: Using Queued invalidation Nov 12 23:14:06 base kernel: DMAR: dmar1: Using Queued invalidation Nov 12 23:14:06 base kernel: DMAR: Setting RMRR: Nov 12 23:14:06 base kernel: DMAR: Setting identity map for device 0000:00:02.0 [0xdd000000 - 0xdf1fffff] Nov 12 23:14:06 base kernel: DMAR: Setting identity map for device 0000:00:14.0 [0xda911000 - 0xda922fff] Nov 12 23:14:06 base kernel: DMAR: Setting identity map for device 0000:00:1a.0 [0xda911000 - 0xda922fff] Nov 12 23:14:06 base kernel: DMAR: Setting identity map for device 0000:00:1d.0 [0xda911000 - 0xda922fff] Nov 12 23:14:06 base kernel: DMAR: Prepare 0-16MiB unity mapping for LPC Nov 12 23:14:06 base kernel: DMAR: Setting identity map for device 0000:00:1f.0 [0x0 - 0xffffff] Nov 12 23:14:06 base kernel: DMAR: Intel(R) Virtualization Technology for Directed I/O Nov 12 23:14:06 base kernel: [drm] DMAR active, disabling use of stolen memory Nov 12 23:15:31 base kernel: pci-stub 0000:02:00.0: kvm assign device failed ret -22 Nov 12 23:17:38 base kernel: Linux version 4.1.9 (root@base) (gcc version 4.8.3 20140911 (Red Hat 4.8.3-9) (GCC) ) #1 SMP Thu Nov 12 22:10:21 EET 2015 Nov 12 23:17:38 base kernel: ACPI: DMAR 0x00000000DA99F4A8 0000B8 (v01 INTEL SNB 00000001 INTL 00000001) Nov 12 23:17:38 base kernel: dmar: Host address width 36 Nov 12 23:17:38 base kernel: dmar: DRHD base: 0x000000fed90000 flags: 0x0 Nov 12 23:17:38 base kernel: dmar: IOMMU 0: reg_base_addr fed90000 ver 1:0 cap c0000020e60262 ecap f0101a Nov 12 23:17:38 base kernel: dmar: DRHD base: 0x000000fed91000 flags: 0x1 Nov 12 23:17:38 base kernel: dmar: IOMMU 1: reg_base_addr fed91000 ver 1:0 cap c9008020660262 ecap f010da Nov 12 23:17:38 base kernel: dmar: RMRR base: 0x000000da911000 end: 0x000000da922fff Nov 12 23:17:38 base kernel: dmar: RMRR base: 0x000000dd000000 end: 0x000000df1fffff Nov 12 23:17:38 base kernel: DMAR: No ATSR found Nov 12 23:17:38 base kernel: IOMMU: dmar0 using Queued invalidation Nov 12 23:17:38 base kernel: IOMMU: dmar1 using Queued invalidation Nov 12 23:17:38 base kernel: [drm] DMAR active, disabling use of stolen memory Nov 12 23:18:55 base kernel: pci-stub 0000:02:00.0: kvm assign device Nov 12 23:18:55 base kernel: pci-stub 0000:02:00.1: kvm assign device Best Regards, Juhani -- Juhani Rautiainen jra...@iki.fi -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majord...@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
