On Wednesday 09 June 2021, Christian König wrote: > Am 08.06.21 um 23:59 schrieb Ondrej Zary: > > On Tuesday 08 June 2021 22:01:56 Ondrej Zary wrote: > >> On Tuesday 08 June 2021 20:47:42 Ondrej Zary wrote: > >>> On Monday 07 June 2021 22:58:43 Ondrej Zary wrote: > >>>> On Sunday 06 June 2021 23:16:03 Ondrej Zary wrote: > >>>>> On Saturday 05 June 2021 23:34:23 Ondrej Zary wrote: > >>>>>> On Saturday 05 June 2021 21:43:52 Ondrej Zary wrote: > >>>>>>> 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. > >>>>>> So it is the same bug. Broken since 5.11. This revert fixes it in 5.11: > >>>>>> https://nam11.safelinks.protection.outlook.com/?url=https%3A%2F%2Flists.freedesktop.org%2Farchives%2Fdri-devel%2F2021-February%2F298531.html&data=04%7C01%7Cchristian.koenig%40amd.com%7C605d2e3757ba466bb02a08d92ac8a895%7C3dd8961fe4884e608e11a82d994e183d%7C0%7C0%7C637587864017853132%7CUnknown%7CTWFpbGZsb3d8eyJWIjoiMC4wLjAwMDAiLCJQIjoiV2luMzIiLCJBTiI6Ik1haWwiLCJXVCI6Mn0%3D%7C3000&sdata=M5KXSwD%2Fnro3cnCo8Nx4llFu%2Fj2T%2FGQAaMBLeGl0XMc%3D&reserved=0 > >>>>>> > >>>>>> Added some debug printks to nouveau_bo_sync_for_device: > >>>>>> [ 22.225048] ttm_dma=fc33b500 > >>>>>> [ 22.225066] ttm_dma->num_pages=18 > >>>>>> [ 22.225071] i=0 num_pages=16 > >>>>>> [ 22.225077] ttm_dma->dma_address=00000000 > >>>>>> [ 22.225094] BUG: kernel NULL pointer dereference, address: 00000000 > >>>>>> > >>>>>> So ttm->dma_address is NULL. > >>>>>> > >>>>> Tested reverting f295c8cfec833c2707ff1512da10d65386dde7af again and it does not work... > >>>>> Not sure what I did before. > >>>>> > >>>>> Bisecting between 5.10 and 5.11 is impossible - I keep hitting neverending stream of bugs. > >>>>> As always with nouveau... > >>>> e34b8feeaa4b65725b25f49c9b08a0f8707e8e86 seems to be the first bad commit > >>>> Going back one commit makes it crash in a different way: > >>>> > >>>> [ 55.444208] BUG: kernel NULL pointer dereference, address: 000001b0 > >>>> [ 55.444219] #PF: supervisor read access in kernel mode > >>>> [ 55.444222] #PF: error_code(0x0000) - not-present page > >>>> [ 55.444225] *pde = 00000000 > >>>> [ 55.444231] Oops: 0000 [#1] SMP > >>>> [ 55.444237] CPU: 0 PID: 1740 Comm: Xorg Not tainted 5.9.0-rc5+ #361 > >>>> [ 55.444240] Hardware name: /848P-ICH5, BIOS 6.00 PG 02/03/2005 > >>>> [ 55.444321] EIP: nouveau_bo_wr16+0x8/0x27 [nouveau] > >>>> [ 55.444326] Code: 85 ff 74 0d 80 7d f3 00 74 07 80 a6 f4 01 00 00 fe 89 f0 e8 0c ef ff ff 8d 65 f4 89 f8 5b 5e 5f 5d c3 55 01 d2 89 e5 53 89 c3 <03> 93 b0 01 00 00 0f b7 c1 f6 83 b8 01 00 00 80 74 07 e8 40 49 69 > >>>> [ 55.444330] EAX: 00000000 EBX: 00000000 ECX: 00000000 EDX: 00000000 > >>>> [ 55.444334] ESI: 00000020 EDI: e7a14400 EBP: e786fd98 ESP: e786fd94 > >>>> [ 55.444338] DS: 007b ES: 007b FS: 00d8 GS: 0033 SS: 0068 EFLAGS: 00210246 > >>>> [ 55.444341] CR0: 80050033 CR2: 000001b0 CR3: 27896000 CR4: 00000690 > >>>> [ 55.444344] Call Trace: > >>>> [ 55.444395] nv04_crtc_cursor_set+0x148/0x1d8 [nouveau] > >>>> [ 55.444442] ? ttm_bo_reserve.constprop.15+0x1c/0x1c [nouveau] > >>>> [ 55.444451] drm_mode_cursor_common+0x13b/0x1ad > >>>> [ 55.444497] ? ttm_bo_reserve.constprop.15+0x1c/0x1c [nouveau] > >>>> [ 55.444504] drm_mode_cursor_ioctl+0x2e/0x36 > >>>> [ 55.444509] ? drm_mode_setplane+0x203/0x203 > >>>> [ 55.444514] drm_ioctl_kernel+0x66/0x99 > >>>> [ 55.444518] drm_ioctl+0x211/0x2d8 > >>>> [ 55.444522] ? drm_mode_setplane+0x203/0x203 > >>>> [ 55.444529] ? _cond_resched+0x1e/0x22 > >>>> [ 55.444533] ? mutex_lock+0xb/0x24 > >>>> [ 55.444582] ? nouveau_bo_add_io_reserve_lru+0x53/0x58 [nouveau] > >>>> [ 55.444589] ? rpm_resume.part.13+0x72/0x365 > >>>> [ 55.444594] ? ktime_get_mono_fast_ns+0x5e/0xf2 > >>>> [ 55.444598] ? __pm_runtime_resume+0x5b/0x63 > >>>> [ 55.444647] nouveau_drm_ioctl+0x65/0x81 [nouveau] > >>>> [ 55.444696] ? nouveau_cli_work+0xc3/0xc3 [nouveau] > >>>> [ 55.444702] vfs_ioctl+0x1a/0x24 > >>>> [ 55.444706] __ia32_sys_ioctl+0x583/0x59d > >>>> [ 55.444711] ? doublefault_shim+0x120/0x120 > >>>> [ 55.444717] ? exit_to_user_mode_prepare+0x71/0xba > >>>> [ 55.444721] do_int80_syscall_32+0x2c/0x39 > >>>> [ 55.444725] entry_INT80_32+0xf0/0xf0 > >>>> [ 55.444729] EIP: 0xb7fb2092 > >>>> [ 55.444733] 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 > >>>> [ 55.444737] EAX: ffffffda EBX: 0000000e ECX: c01c64a3 EDX: bfe89750 > >>>> [ 55.444741] ESI: 02580b40 EDI: c01c64a3 EBP: 0000000e ESP: bfe89704 > >>>> [ 55.444744] DS: 007b ES: 007b FS: 0000 GS: 0033 SS: 007b EFLAGS: 00200292 > >>>> [ 55.444748] Modules linked in: i2c_dev nouveau serial_cs snd_intel8x0 snd_ac97_codec wmi hwmon ttm ac97_bus 8139cp snd_pcm pcmcia snd_timer snd sg soundcore psmouse yenta_socket serio_raw pcmcia_rsrc pcmcia_core intel_agp parport_pc parport > >>>> [ 55.444769] CR2: 00000000000001b0 > >>>> [ 55.444774] ---[ end trace e2b0d4c3c2e4e488 ]--- > >>>> [ 55.444827] EIP: nouveau_bo_wr16+0x8/0x27 [nouveau] > >>>> [ 55.444831] Code: 85 ff 74 0d 80 7d f3 00 74 07 80 a6 f4 01 00 00 fe 89 f0 e8 0c ef ff ff 8d 65 f4 89 f8 5b 5e 5f 5d c3 55 01 d2 89 e5 53 89 c3 <03> 93 b0 01 00 00 0f b7 c1 f6 83 b8 01 00 00 80 74 07 e8 40 49 69 > >>>> [ 55.444835] EAX: 00000000 EBX: 00000000 ECX: 00000000 EDX: 00000000 > >>>> [ 55.444838] ESI: 00000020 EDI: e7a14400 EBP: e786fd98 ESP: e786fd94 > >>>> [ 55.444842] DS: 007b ES: 007b FS: 00d8 GS: 0033 SS: 0068 EFLAGS: 00210246 > >>>> [ 55.444845] CR0: 80050033 CR2: 000001b0 CR3: 27896000 CR4: 00000690 > >>> Bisected this crash: > >>> # first bad commit: [141b15e59175aa174ca1f7596188bd15a7ca17ba] drm/nouveau: move io_reserve_lru handling into the driver v5 > >>> > >>> Adding Christian König to CC. > >> Tracked it down to an uninitialized variable bug. > >> I see now that this was fixed by aea656b0d05ec5b8ed5beb2f94c4dd42ea834e9d. > > So the first bad commit for the original bug is e34b8feeaa4b65725b25f49c9b08a0f8707e8e86 > > (as bisected before). > > Going one commit back and fixing the uninitialized variable and endian bugs manually makes nouveau work. > > Thanks for the heads up. So the problem with my patch is already fixed, > isn't it? The NULL pointer dereference in nouveau_bo_wr16 introduced in 141b15e59175aa174ca1f7596188bd15a7ca17ba was fixed by aea656b0d05ec5b8ed5beb2f94c4dd42ea834e9d. That's the bug I hit when bisecting the original problem: NULL pointer dereference in nouveau_bo_sync_for_device It's caused by: # first bad commit: [e34b8feeaa4b65725b25f49c9b08a0f8707e8e86] drm/ttm: merge ttm_dma_tt back into ttm_tt -- Ondrej Zary
