Hi, I am running qemu with kvm and VT-d enabled and a couple of PCI devices assigned to the guest VM. Both host and guest are running linux 2.6 kernel. The passthrough works fine, but when I exit the VM, the host kernel crashes with the following backtrace: <4>[ 5569.836893] Process qemu-system-x86 (pid: 2925, threadinfo ffff8801f5f40000, task ffff88024fa28720) <0>[ 5569.944946] Stack: <4>[ 5569.968845] ffff8801f5f41aa8 ffffffff811a45fb ffff88024f04b680 ffff88024f049980 <4>[ 5570.057156] ffff88024f04b680 ffff88024f049988 ffff8801f5f41b08 ffffffff811a6371 <4>[ 5570.145470] ffff8801f5f41ad8 ffffffff81391045 0000000000000246 ffff88024f049990 <0>[ 5570.233785] Call Trace: <4>[ 5570.262880] [<ffffffff811a45fb>] iommu_detach_dependent_devices+0x25/0x91 <4>[ 5570.344958] [<ffffffff811a6371>] vm_domain_exit+0xf8/0x28b <4>[ 5570.411457] [<ffffffff81391045>] ? sub_preempt_count+0x92/0xa6 <4>[ 5570.482106] [<ffffffff811a651a>] intel_iommu_domain_destroy+0x16/0x18 <4>[ 5570.560030] [<ffffffff811fb5ea>] iommu_domain_free+0x16/0x22 <4>[ 5570.628611] [<ffffffffa0006261>] kvm_iommu_unmap_guest+0x22/0x28 [kvm] <4>[ 5570.707570] [<ffffffffa0009b7b>] kvm_arch_destroy_vm+0x19/0x12a [kvm] <4>[ 5570.785492] [<ffffffffa0002614>] kvm_put_kvm+0xe6/0x129 [kvm] <4>[ 5570.855102] [<ffffffffa0002eb3>] kvm_vcpu_release+0x13/0x17 [kvm] <4>[ 5570.928867] [<ffffffff8109cdfc>] fput+0x117/0x1be <4>[ 5570.986013] [<ffffffff8109a147>] filp_close+0x63/0x6d <4>[ 5571.047314] [<ffffffff810342dd>] put_files_struct+0x6f/0xda <4>[ 5571.114845] [<ffffffff8103438e>] exit_files+0x46/0x4e <4>[ 5571.176145] [<ffffffff81035b3d>] do_exit+0x1fc/0x681 <4>[ 5571.236416] [<ffffffffa000dedc>] ? kvm_arch_vcpu_ioctl_run+0xc2d/0xc55 [kvm] <4>[ 5571.321605] [<ffffffff8138cc41>] ? __mutex_lock_slowpath+0x26c/0x294 <4>[ 5571.398490] [<ffffffff81036034>] do_group_exit+0x72/0x9a <4>[ 5571.462907] [<ffffffff8103fec9>] get_signal_to_deliver+0x331/0x350 <4>[ 5571.537719] [<ffffffff81001f0f>] do_signal+0x6d/0x69a <4>[ 5571.599013] [<ffffffff811da1fc>] ? put_ldisc+0x92/0x97 <4>[ 5571.661353] [<ffffffff810a95ea>] ? do_vfs_ioctl+0x527/0x576 <4>[ 5571.728887] [<ffffffff81002563>] do_notify_resume+0x27/0x51 <4>[ 5571.796419] [<ffffffff810a968c>] ? sys_ioctl+0x53/0x65 <4>[ 5571.858758] [<ffffffff81002b9b>] int_signal+0x12/0x17 <0>[ 5571.920058] Code: 48 85 d2 0f 95 c0 c9 c3 55 80 7f 4a 00 48 89 f8 48 89 e5 75 46 31 d2 48 8b 40 10 48 83 78 10 00 75 05 48 89 d0 eb 36 48 8b 40 38 <80> 78 4a 00 48 89 c2 74 e3 80 78 4b 07 74 23 80 3d 86 b5 5a 00 <1>[ 5572.145516] RIP [<ffffffff81197f8c>] pci_find_upstream_pcie_bridge+0x23/0x57 <4>[ 5572.230712] RSP <ffff8801f5f41a78> The two PCI devices in question are behind a PCIe bridge which is connected to the rootport. The crash seems to be happening when cleaning up the PCIe tree of the passed-through PCI devices. I tried passing through the downstream ports of the bridge as well, but that is not supported by qemu. Am I doing something wrong/unexpected here ? Any help in understanding this issue will help me fix the issue properly. Thanks, Ganesh -- To unsubscribe from this list: send the line "unsubscribe kvm" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
