I built a v4.11-rc1 kernel, and booted it in a KVM guest and got this oops during startup. My config is attached: [ 2.386786] virtio-pci 0000:00:07.0: virtio_pci: leaving for legacy driver [ 2.395650] BUG: unable to handle kernel paging request at ffff97a3ec5f4000 [ 2.396005] IP: string+0x43/0x80 [ 2.396005] PGD 2d25b067 [ 2.396005] PUD 2d25f067 [ 2.396005] PMD 12c696063 [ 2.396005] PTE 800000012c5f4161 [ 2.396005] [ 2.396005] Oops: 0003 [#1] SMP [ 2.396005] Modules linked in: virtio_console(+) virtio_blk(+) drm crc32c_intel serio_raw virtio_pci virtio_ring ata_generic virtio pata_acpi floppy [ 2.403662] CPU: 0 PID: 348 Comm: systemd-udevd Not tainted 4.11.0-rc1 #17 [ 2.403662] Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.9.3-1.fc25 04/01/2014 [ 2.403662] task: ffff97a3ee269d80 task.stack: ffffac9cc0cdc000 [ 2.403662] RIP: 0010:string+0x43/0x80 [ 2.403662] RSP: 0018:ffffac9cc0cdf958 EFLAGS: 00010206 [ 2.403662] RAX: ffff97a3fa781999 RBX: ffff97a3ec5f4000 RCX: ffff0a00ffffff04 [ 2.412007] RDX: 0000000000000076 RSI: 0000000000000000 RDI: ffff97a3ec5f4000 [ 2.412007] RBP: ffffac9cc0cdf958 R08: ffff97a3fa781997 R09: ffff97a3ec5f4100 [ 2.412007] R10: ffff97a3ec2d9000 R11: ffff97a3fffe6e58 R12: ffff97a3ec5f4100 [ 2.412007] R13: 0000000000000100 R14: ffffffffc02a46ca R15: ffffffffc02a46ca [ 2.412007] FS: 00007fc2ee06d640(0000) GS:ffff97a3ffc00000(0000) knlGS:0000000000000000 [ 2.412007] CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 [ 2.412007] CR2: ffff97a3ec5f4000 CR3: 000000012d91e000 CR4: 00000000000406f0 [ 2.412007] Call Trace: [ 2.412007] vsnprintf+0x2d7/0x500 [ 2.412007] snprintf+0x49/0x60 [ 2.412007] vp_find_vqs+0x206/0x4e0 [virtio_pci] [ 2.412007] init_vqs+0x18b/0x2f0 [virtio_console] [ 2.412007] virtcons_probe+0xc6/0x350 [virtio_console] [ 2.412007] virtio_dev_probe+0x144/0x1e0 [virtio] [ 2.412007] driver_probe_device+0x2bb/0x460 [ 2.412007] __driver_attach+0xdf/0xf0 [ 2.412007] ? driver_probe_device+0x460/0x460 [ 2.412007] bus_for_each_dev+0x6c/0xc0 [ 2.412007] driver_attach+0x1e/0x20 [ 2.412007] bus_add_driver+0x170/0x270 [ 2.412007] driver_register+0x60/0xe0 [ 2.412007] ? virtio_cons_early_init+0x1d/0x1d [virtio_console] [ 2.412007] register_virtio_driver+0x20/0x30 [virtio] [ 2.412007] init+0x9f/0xfe3 [virtio_console] [ 2.412007] ? virtio_cons_early_init+0x1d/0x1d [virtio_console] [ 2.412007] do_one_initcall+0x52/0x1a0 [ 2.412007] ? free_hot_cold_page+0x191/0x300 [ 2.412007] ? kmem_cache_alloc_trace+0x159/0x1b0 [ 2.412007] ? do_init_module+0x27/0x1f8 [ 2.412007] do_init_module+0x5f/0x1f8 [ 2.412007] load_module+0x2651/0x2a20 [ 2.412007] ? __symbol_put+0x60/0x60 [ 2.412007] ? vfs_read+0x11b/0x130 [ 2.412007] SYSC_finit_module+0xdf/0x110 [ 2.412007] SyS_finit_module+0xe/0x10 [ 2.412007] do_syscall_64+0x67/0x180 [ 2.412007] entry_SYSCALL64_slow_path+0x25/0x25 [ 2.412007] RIP: 0033:0x7fc2eccc6bf9 [ 2.412007] RSP: 002b:00007ffc233ca698 EFLAGS: 00000246 ORIG_RAX: 0000000000000139 [ 2.412007] RAX: ffffffffffffffda RBX: 000055ffbe27ff60 RCX: 00007fc2eccc6bf9 [ 2.412007] RDX: 0000000000000000 RSI: 00007fc2ed7ff995 RDI: 0000000000000006 [ 2.412007] RBP: 00007fc2ed7ff995 R08: 0000000000000000 R09: 00007ffc233cac10 [ 2.412007] R10: 0000000000000006 R11: 0000000000000246 R12: 0000000000000000 [ 2.412007] R13: 000055ffbe27df50 R14: 0000000000020000 R15: 000055ffbe27ff60 [ 2.412007] Code: ff 76 40 48 85 f6 74 4e 48 8d 42 01 0f b6 12 84 d2 74 43 49 01 c0 31 f6 eb 0c 48 83 c0 01 0f b6 50 ff 84 d2 74 13 49 39 f9 76 02 <88> 17 48 83 c7 01 83 c6 01 49 39 c0 75 e1 4c 89 ca e8 07 ff ff [ 2.412007] RIP: string+0x43/0x80 RSP: ffffac9cc0cdf958 [ 2.412007] CR2: ffff97a3ec5f4000 [ 2.412007] ---[ end trace eed8a51dc2a4749d ]--- (gdb) list *(vp_find_vqs+0x18b) 0x183b is in vp_find_vqs (drivers/virtio/virtio_pci_common.c:227). 222 if (callbacks[i]) 223 msix_vec = allocated_vectors; 224 else 225 msix_vec = VIRTIO_MSI_NO_VECTOR; 226 227 vqs[i] = vp_dev->setup_vq(vp_dev, i, callbacks[i], names[i], 228 msix_vec); 229 if (IS_ERR(vqs[i])) { 230 err = PTR_ERR(vqs[i]); 231 goto out_remove_vqs; -- Jeff Layton