Hello, I'm testing 5.13.0-rc4 and nouveau crashes with NULL pointer dereference in nouveau_bo_sync_for_device. Found various reports like this but that was back in februaryso that should be fixed now. [ 21.003216] BUG: kernel NULL pointer dereference, address: 00000000 [ 21.003235] #PF: supervisor read access in kernel mode [ 21.003243] #PF: error_code(0x0000) - not-present page [ 21.003250] *pde = 00000000 [ 21.003258] Oops: 0000 [#1] SMP [ 21.003268] CPU: 0 PID: 222 Comm: systemd-udevd Not tainted 5.13.0-rc4+ #327 [ 21.003278] Hardware name: /848P-ICH5, BIOS 6.00 PG 02/03/2005 [ 21.003285] EIP: nouveau_bo_sync_for_device+0x9e/0xbf [nouveau] [ 21.003571] Code: 02 89 45 e8 01 d1 8b 19 89 5d ec bb 01 00 00 00 3b 5d e8 74 0d 89 d8 c1 e0 05 03 45 ec 39 04 99 74 1e 8b 46 10 89 d9 c1 e1 0c <8b> 14 10 8b 47 e0 8b 40 08 6a 01 e8 d5 03 55 df 01 5d f0 58 eb ae [ 21.003588] EAX: 00000000 EBX: 00000010 ECX: 00010000 EDX: 00000000 [ 21.003597] ESI: c3e90280 EDI: c185a494 EBP: c2ed7c10 ESP: c2ed7bf8 [ 21.003606] DS: 007b ES: 007b FS: 00d8 GS: 0033 SS: 0068 EFLAGS: 00210206 [ 21.003615] CR0: 80050033 CR2: 00000000 CR3: 02ecb000 CR4: 00000690 [ 21.003625] Call Trace: [ 21.003635] nouveau_bo_validate+0x3f/0x48 [nouveau] [ 21.003911] nouveau_bo_pin+0xf0/0x187 [nouveau] [ 21.004182] nouveau_channel_prep+0xc0/0x269 [nouveau] [ 21.004454] nouveau_channel_new+0x3c/0x5f5 [nouveau] [ 21.004725] ? slab_free_freelist_hook+0x3b/0xa7 [ 21.004740] ? kfree+0x9e/0x11a [ 21.004749] ? nvif_object_sclass_put+0xd/0x16 [nouveau] [ 21.004944] nouveau_drm_device_init+0x2e2/0x646 [nouveau] [ 21.005186] ? pci_enable_device_flags+0x23/0x97 [ 21.005202] nouveau_drm_probe+0xe5/0x182 [nouveau] [ 21.005443] ? nouveau_drm_device_init+0x646/0x646 [nouveau] [ 21.005683] pci_device_probe+0x89/0xe9 [ 21.005696] really_probe+0x127/0x2b9 [ 21.005707] driver_probe_device+0x62/0x89 [ 21.005715] device_driver_attach+0x2e/0x41 [ 21.005724] __driver_attach+0x83/0x8a [ 21.005732] bus_for_each_dev+0x4c/0x66 [ 21.005740] driver_attach+0x14/0x16 [ 21.005747] ? device_driver_attach+0x41/0x41 [ 21.005756] bus_add_driver+0xc5/0x16c [ 21.005764] driver_register+0x87/0xb9 [ 21.005772] __pci_register_driver+0x38/0x3b [ 21.005780] ? 0xf0be4000 [ 21.005787] nouveau_drm_init+0x14c/0x1000 [nouveau] [ 21.005964] do_one_initcall+0x5a/0x134 [ 21.005975] ? __vunmap+0x124/0x12d [ 21.005984] ? __vunmap+0x124/0x12d [ 21.005992] ? kmem_cache_alloc+0xa8/0xb6 [ 21.006001] ? do_init_module+0x17/0x1cf [ 21.006012] do_init_module+0x46/0x1cf [ 21.006021] load_module+0x1799/0x1bcb [ 21.006032] __ia32_sys_finit_module+0x72/0x7a [ 21.006044] do_int80_syscall_32+0x53/0x62 [ 21.006054] entry_INT80_32+0xf0/0xf0 [ 21.006063] EIP: 0xb7f40092 [ 21.006071] Code: 00 00 00 e9 90 ff ff ff ff a3 24 00 00 00 68 30 00 00 00 e9 80 ff ff ff ff a3 e8 ff ff ff 66 90 00 00 00 00 00 00 00 00 cd 80 <c3> 8d b4 26 00 00 00 00 8d b6 00 00 00 00 8b 1c 24 c3 8d b4 26 00 [ 21.006086] EAX: ffffffda EBX: 00000010 ECX: b7e9bbdd EDX: 00000000 [ 21.006095] ESI: 008f27d0 EDI: 008f9e10 EBP: 00000000 ESP: bfa140b8 [ 21.006103] DS: 007b ES: 007b FS: 0000 GS: 0033 SS: 007b EFLAGS: 00200296 [ 21.006114] Modules linked in: nouveau(+) snd_intel8x0 snd_ac97_codec pcmcia wmi hwmon ac97_bus yenta_socket pcmcia_rsrc drm_ttm_helper snd_pcm ttm snd_timer pcmcia_core psmouse 8139cp snd sg soundcore serio_raw parport_pc intel_agp parport [ 21.006165] CR2: 0000000000000000 [ 21.006201] ---[ end trace 02dc541683feafc6 ]--- [ 21.006211] EIP: nouveau_bo_sync_for_device+0x9e/0xbf [nouveau] [ 21.006460] Code: 02 89 45 e8 01 d1 8b 19 89 5d ec bb 01 00 00 00 3b 5d e8 74 0d 89 d8 c1 e0 05 03 45 ec 39 04 99 74 1e 8b 46 10 89 d9 c1 e1 0c <8b> 14 10 8b 47 e0 8b 40 08 6a 01 e8 d5 03 55 df 01 5d f0 58 eb ae [ 21.006476] EAX: 00000000 EBX: 00000010 ECX: 00010000 EDX: 00000000 [ 21.006485] ESI: c3e90280 EDI: c185a494 EBP: c2ed7c10 ESP: c2ed7bf8 [ 21.006494] DS: 007b ES: 007b FS: 00d8 GS: 0033 SS: 0068 EFLAGS: 00210206 [ 21.006503] CR0: 80050033 CR2: 00000000 CR3: 02ecb000 CR4: 00000690 -- Ondrej Zary