[linux.git drm/ttm]: NULL pointer dereference upon driver probe

Tetsuo Handa penguin-kernel at i-love.sakura.ne.jp
Thu Aug 6 14:55:16 UTC 2020


Hello.

Commit 2ddef17678bc2ea1 ("drm/ttm: make TT creation purely optional v3") broke vmwgfx .

At first I suspected it is "drm/atomic-helper: reset vblank on crtc reset" or around that,
but bisection said it is not. I have no idea what is going on. Please have a look.

--- Crash pattern 1 ---

[    0.990745][    T1] Linux agpgart interface v0.103
[    0.991945][    T1] [drm] DMA map mode: Caching DMA mappings.
[    0.993009][    T1] [drm] Capabilities:
[    0.993972][    T1] [drm]   Rect copy.
[    0.994011][    T1] [drm]   Cursor.
[    0.994049][    T1] [drm]   Cursor bypass.
[    0.994984][    T1] [drm]   Cursor bypass 2.
[    0.995972][    T1] [drm]   8bit emulation.
[    0.997057][    T1] [drm]   Alpha cursor.
[    0.997906][    T1] [drm]   3D.
[    0.998947][    T1] [drm]   Extended Fifo.
[    0.999972][    T1] [drm]   Multimon.
[    1.000011][    T1] [drm]   Pitchlock.
[    1.000932][    T1] [drm]   Irq mask.
[    1.001972][    T1] [drm]   Display Topology.
[    1.002906][    T1] [drm]   GMR.
[    1.003906][    T1] [drm]   Traces.
[    1.004975][    T1] [drm]   GMR2.
[    1.005987][    T1] [drm]   Screen Object 2.
[    1.006983][    T1] [drm]   Command Buffers.
[    1.007981][    T1] [drm]   Command Buffers 2.
[    1.008020][    T1] [drm]   Guest Backed Resources.
[    1.008982][    T1] [drm]   DX Features.
[    1.009965][    T1] [drm]   HP Command Queue.
[    1.010982][    T1] [drm] Capabilities2:
[    1.011982][    T1] [drm]   Grow oTable.
[    1.012020][    T1] [drm]   IntraSurface copy.
[    1.012983][    T1] [drm] Max GMR ids is 64
[    1.013975][    T1] [drm] Max number of GMR pages is 65536
[    1.015968][    T1] [drm] Max dedicated hypervisor surface memory is 0 kiB
[    1.017983][    T1] [drm] Maximum display memory size is 262144 kiB
[    1.018982][    T1] [drm] VRAM at 0xe8000000 size is 4096 kiB
[    1.019972][    T1] [drm] MMIO at 0xfe000000 size is 256 kiB
[    1.021466][    T1] [TTM] Zone  kernel: Available graphics memory: 1880776 KiB
[    1.022965][    T1] [TTM] Initializing pool allocator
[    1.023975][    T1] [TTM] Initializing DMA pool allocator
[    1.026297][    T1] BUG: kernel NULL pointer dereference, address: 0000000000000190
[    1.027257][    T1] #PF: supervisor read access in kernel mode
[    1.027257][    T1] #PF: error_code(0x0000) - not-present page
[    1.027257][    T1] PGD 0 P4D 0 
[    1.027257][    T1] Oops: 0000 [#1] SMP
[    1.027257][    T1] CPU: 3 PID: 1 Comm: swapper/0 Not tainted 5.8.0-rc2+ #779
[    1.027257][    T1] Hardware name: VMware, Inc. VMware Virtual Platform/440BX Desktop Reference Platform, BIOS 6.00 02/27/2020
[    1.027257][    T1] RIP: 0010:drm_dev_has_vblank+0x0/0x10
[    1.027257][    T1] Code: 84 2f ff ff ff e9 10 ff ff ff 89 f1 44 89 ff 45 31 d2 d3 e7 89 f9 e9 f7 fe ff ff cc cc cc cc cc cc cc cc cc cc cc cc cc cc cc <8b> 87 90 01 00 00 85 c0 0f 95 c0 c3 0f 1f 40 00 8b 87 90 00 00 00
[    1.027257][    T1] RSP: 0000:ffffaf8280013b50 EFLAGS: 00010286
[    1.027257][    T1] RAX: ffff9149f6fe1a00 RBX: ffff9149f8812000 RCX: 0000000000000000
[    1.027257][    T1] RDX: 0000000000000000 RSI: ffff9149f6fe1a00 RDI: 0000000000000000
[    1.027257][    T1] RBP: ffffaf8280013b68 R08: 0000000000000025 R09: 0000000000000000
[    1.027257][    T1] R10: ffff9149f6fe1a00 R11: ffff9149f6e3ac7a R12: ffff9149f6fe1a00
[    1.027257][    T1] R13: ffff9149f6ea9000 R14: ffff9149f8810000 R15: ffff9149f8812000
[    1.027257][    T1] FS:  0000000000000000(0000) GS:ffff9149faec0000(0000) knlGS:0000000000000000
[    1.027257][    T1] CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
[    1.027257][    T1] CR2: 0000000000000190 CR3: 0000000081009001 CR4: 00000000001606e0
[    1.027257][    T1] Call Trace:
[    1.027257][    T1]  ? __drm_atomic_helper_crtc_reset+0x1e/0x50
[    1.027257][    T1]  vmw_du_crtc_reset+0x46/0x60
[    1.027257][    T1]  vmw_kms_stdu_init_display+0x216/0x380
[    1.027257][    T1]  vmw_kms_init+0x6d/0xc0
[    1.027257][    T1]  vmw_driver_load.cold.21+0xba2/0xdf8
[    1.027257][    T1]  vmw_probe+0x5f/0xb0
[    1.027257][    T1]  pci_device_probe+0xcf/0x140
[    1.027257][    T1]  really_probe+0x1b3/0x3d0
[    1.027257][    T1]  ? rdinit_setup+0x27/0x27
[    1.027257][    T1]  driver_probe_device+0xe3/0x150
[    1.027257][    T1]  device_driver_attach+0x53/0x60
[    1.027257][    T1]  __driver_attach+0x87/0x140
[    1.027257][    T1]  ? device_driver_attach+0x60/0x60
[    1.027257][    T1]  ? device_driver_attach+0x60/0x60
[    1.027257][    T1]  bus_for_each_dev+0x6e/0xb0
[    1.027257][    T1]  ? _cond_resched+0x14/0x30
[    1.027257][    T1]  driver_attach+0x19/0x20
[    1.027257][    T1]  bus_add_driver+0x14a/0x1f0
[    1.027257][    T1]  driver_register+0x6b/0xc0
[    1.027257][    T1]  __pci_register_driver+0x4f/0x60
[    1.027257][    T1]  vmwgfx_init+0x28/0x3f
[    1.027257][    T1]  ? ttm_init+0x5e/0x5e
[    1.027257][    T1]  do_one_initcall+0x43/0x1a0
[    1.027257][    T1]  kernel_init_freeable+0x14e/0x1b9
[    1.027257][    T1]  ? rest_init+0x9b/0x9b
[    1.027257][    T1]  kernel_init+0x9/0xf5
[    1.027257][    T1]  ret_from_fork+0x1f/0x30
[    1.027257][    T1] Modules linked in:
[    1.027257][    T1] CR2: 0000000000000190
[    1.027257][    T1] ---[ end trace 8db9188472e5abda ]---
[    1.027257][    T1] RIP: 0010:drm_dev_has_vblank+0x0/0x10
[    1.027257][    T1] Code: 84 2f ff ff ff e9 10 ff ff ff 89 f1 44 89 ff 45 31 d2 d3 e7 89 f9 e9 f7 fe ff ff cc cc cc cc cc cc cc cc cc cc cc cc cc cc cc <8b> 87 90 01 00 00 85 c0 0f 95 c0 c3 0f 1f 40 00 8b 87 90 00 00 00
[    1.027257][    T1] RSP: 0000:ffffaf8280013b50 EFLAGS: 00010286
[    1.027257][    T1] RAX: ffff9149f6fe1a00 RBX: ffff9149f8812000 RCX: 0000000000000000
[    1.027257][    T1] RDX: 0000000000000000 RSI: ffff9149f6fe1a00 RDI: 0000000000000000
[    1.027257][    T1] RBP: ffffaf8280013b68 R08: 0000000000000025 R09: 0000000000000000
[    1.027257][    T1] R10: ffff9149f6fe1a00 R11: ffff9149f6e3ac7a R12: ffff9149f6fe1a00
[    1.027257][    T1] R13: ffff9149f6ea9000 R14: ffff9149f8810000 R15: ffff9149f8812000
[    1.027257][    T1] FS:  0000000000000000(0000) GS:ffff9149faec0000(0000) knlGS:0000000000000000
[    1.027257][    T1] CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
[    1.027257][    T1] CR2: 0000000000000190 CR3: 0000000081009001 CR4: 00000000001606e0
[    1.027257][    T1] Kernel panic - not syncing: Attempted to kill init! exitcode=0x00000009
[    1.027257][    T1] Kernel Offset: 0xf000000 from 0xffffffff81000000 (relocation range: 0xffffffff80000000-0xffffffffbfffffff)

--- Crash pattern 2 ---

[    1.458665][    T1] Linux agpgart interface v0.103
[    1.459068][    T1] [drm] DMA map mode: Caching DMA mappings.
[    1.460076][    T1] [drm] Capabilities:
[    1.461045][    T1] [drm]   Rect copy.
[    1.461065][    T1] [drm]   Cursor.
[    1.462056][    T1] [drm]   Cursor bypass.
[    1.463101][    T1] [drm]   Cursor bypass 2.
[    1.464041][    T1] [drm]   8bit emulation.
[    1.465012][    T1] [drm]   Alpha cursor.
[    1.465032][    T1] [drm]   3D.
[    1.466037][    T1] [drm]   Extended Fifo.
[    1.467092][    T1] [drm]   Multimon.
[    1.468000][    T1] [drm]   Pitchlock.
[    1.468053][    T1] [drm]   Irq mask.
[    1.469037][    T1] [drm]   Display Topology.
[    1.470065][    T1] [drm]   GMR.
[    1.470085][    T1] [drm]   Traces.
[    1.471042][    T1] [drm]   GMR2.
[    1.471062][    T1] [drm]   Screen Object 2.
[    1.472038][    T1] [drm]   Command Buffers.
[    1.473048][    T1] [drm]   Command Buffers 2.
[    1.474045][    T1] [drm]   Guest Backed Resources.
[    1.475055][    T1] [drm]   DX Features.
[    1.476046][    T1] [drm]   HP Command Queue.
[    1.477045][    T1] [drm] Capabilities2:
[    1.478043][    T1] [drm]   Grow oTable.
[    1.479044][    T1] [drm]   IntraSurface copy.
[    1.480055][    T1] [drm] Max GMR ids is 64
[    1.481039][    T1] [drm] Max number of GMR pages is 65536
[    1.482045][    T1] [drm] Max dedicated hypervisor surface memory is 0 kiB
[    1.483047][    T1] [drm] Maximum display memory size is 262144 kiB
[    1.484064][    T1] [drm] VRAM at 0xe8000000 size is 4096 kiB
[    1.485042][    T1] [drm] MMIO at 0xfe000000 size is 256 kiB
[    1.486389][    T1] [TTM] Zone  kernel: Available graphics memory: 1880780 KiB
[    1.488043][    T1] [TTM] Initializing pool allocator
[    1.489054][    T1] [TTM] Initializing DMA pool allocator
[    1.490057][    T1] [drm] Screen Target Display device initialized
[    1.491077][    T1] [drm] width 800
[    1.491999][    T1] [drm] height 480
[    1.492061][    T1] [drm] bpp 32
[    1.494078][    T1] [drm] Fifo max 0x00040000 min 0x00001000 cap 0x0000077f
[    1.495081][    T1] BUG: kernel NULL pointer dereference, address: 000000000000003c
[    1.496056][    T1] #PF: supervisor read access in kernel mode
[    1.496056][    T1] #PF: error_code(0x0000) - not-present page
[    1.496056][    T1] PGD 0 P4D 0 
[    1.496056][    T1] Oops: 0000 [#1] SMP
[    1.496056][    T1] CPU: 0 PID: 1 Comm: swapper/0 Not tainted 5.8.0-rc2+ #783
[    1.496056][    T1] Hardware name: VMware, Inc. VMware Virtual Platform/440BX Desktop Reference Platform, BIOS 6.00 02/27/2020
[    1.496056][    T1] RIP: 0010:vmw_ttm_populate+0x2/0xa0
[    1.496056][    T1] Code: 0f 1f 84 00 00 00 00 00 55 48 8b 86 c8 00 00 00 48 8b 80 80 00 00 00 48 89 e5 48 8b 30 e8 76 5f 00 00 5d c3 0f 1f 40 00 31 c0 <83> 7f 3c 02 75 35 55 48 89 e5 41 56 41 55 41 54 49 89 f4 53 48 89
[    1.496056][    T1] RSP: 0000:ffffb0f880013b10 EFLAGS: 00010246
[    1.496056][    T1] RAX: 0000000000000000 RBX: ffff8a69399c5000 RCX: ffff8a693a4c8000
[    1.496056][    T1] RDX: 0000000000000000 RSI: ffffb0f880013b20 RDI: 0000000000000000
[    1.496056][    T1] RBP: ffffb0f880013b70 R08: ffff8a69399c5000 R09: ffffffffaac72af4
[    1.496056][    T1] R10: ffffffffab044e20 R11: ffff8a693683a178 R12: ffff8a69399c9800
[    1.496056][    T1] R13: ffff8a6936815bc0 R14: ffff8a69399c5618 R15: 0000000000000000
[    1.496056][    T1] FS:  0000000000000000(0000) GS:ffff8a693ae00000(0000) knlGS:0000000000000000
[    1.496056][    T1] CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
[    1.496056][    T1] CR2: 000000000000003c CR3: 0000000108009001 CR4: 00000000001606f0
[    1.496056][    T1] Call Trace:
[    1.496056][    T1]  ? vmw_otables_setup+0x120/0x330
[    1.496056][    T1]  vmw_request_device_late+0x42/0x80
[    1.496056][    T1]  vmw_request_device+0x67/0x260
[    1.496056][    T1]  vmw_driver_load.cold.21+0xcb1/0xdf8
[    1.496056][    T1]  vmw_probe+0x5f/0xb0
[    1.496056][    T1]  pci_device_probe+0xcf/0x140
[    1.496056][    T1]  really_probe+0x1b3/0x3d0
[    1.496056][    T1]  ? rdinit_setup+0x27/0x27
[    1.496056][    T1]  driver_probe_device+0xe3/0x150
[    1.496056][    T1]  device_driver_attach+0x53/0x60
[    1.496056][    T1]  __driver_attach+0x87/0x140
[    1.496056][    T1]  ? device_driver_attach+0x60/0x60
[    1.496056][    T1]  ? device_driver_attach+0x60/0x60
[    1.496056][    T1]  bus_for_each_dev+0x6e/0xb0
[    1.496056][    T1]  ? _cond_resched+0x14/0x30
[    1.496056][    T1]  driver_attach+0x19/0x20
[    1.496056][    T1]  bus_add_driver+0x14a/0x1f0
[    1.496056][    T1]  driver_register+0x6b/0xc0
[    1.496056][    T1]  __pci_register_driver+0x4f/0x60
[    1.496056][    T1]  vmwgfx_init+0x28/0x3f
[    1.496056][    T1]  ? ttm_init+0x5e/0x5e
[    1.496056][    T1]  do_one_initcall+0x43/0x1a0
[    1.496056][    T1]  kernel_init_freeable+0x14e/0x1b9
[    1.496056][    T1]  ? rest_init+0x9b/0x9b
[    1.496056][    T1]  kernel_init+0x9/0xf5
[    1.496056][    T1]  ret_from_fork+0x1f/0x30
[    1.496056][    T1] Modules linked in:
[    1.496056][    T1] CR2: 000000000000003c
[    1.496056][    T1] ---[ end trace 9f43ab7728d116d5 ]---
[    1.496056][    T1] RIP: 0010:vmw_ttm_populate+0x2/0xa0
[    1.496056][    T1] Code: 0f 1f 84 00 00 00 00 00 55 48 8b 86 c8 00 00 00 48 8b 80 80 00 00 00 48 89 e5 48 8b 30 e8 76 5f 00 00 5d c3 0f 1f 40 00 31 c0 <83> 7f 3c 02 75 35 55 48 89 e5 41 56 41 55 41 54 49 89 f4 53 48 89
[    1.496056][    T1] RSP: 0000:ffffb0f880013b10 EFLAGS: 00010246
[    1.496056][    T1] RAX: 0000000000000000 RBX: ffff8a69399c5000 RCX: ffff8a693a4c8000
[    1.496056][    T1] RDX: 0000000000000000 RSI: ffffb0f880013b20 RDI: 0000000000000000
[    1.496056][    T1] RBP: ffffb0f880013b70 R08: ffff8a69399c5000 R09: ffffffffaac72af4
[    1.496056][    T1] R10: ffffffffab044e20 R11: ffff8a693683a178 R12: ffff8a69399c9800
[    1.496056][    T1] R13: ffff8a6936815bc0 R14: ffff8a69399c5618 R15: 0000000000000000
[    1.496056][    T1] FS:  0000000000000000(0000) GS:ffff8a693ae00000(0000) knlGS:0000000000000000
[    1.496056][    T1] CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
[    1.496056][    T1] CR2: 000000000000003c CR3: 0000000108009001 CR4: 00000000001606f0
[    1.496056][    T1] Kernel panic - not syncing: Attempted to kill init! exitcode=0x00000009
[    1.496056][    T1] Kernel Offset: 0x29000000 from 0xffffffff81000000 (relocation range: 0xffffffff80000000-0xffffffffbfffffff)

--- Expected result ---

[    1.282746][    T1] Linux agpgart interface v0.103
[    1.284885][    T1] [drm] DMA map mode: Caching DMA mappings.
[    1.287860][    T1] [drm] Capabilities:
[    1.289812][    T1] [drm]   Rect copy.
[    1.290785][    T1] [drm]   Cursor.
[    1.291784][    T1] [drm]   Cursor bypass.
[    1.292784][    T1] [drm]   Cursor bypass 2.
[    1.293808][    T1] [drm]   8bit emulation.
[    1.294785][    T1] [drm]   Alpha cursor.
[    1.295778][    T1] [drm]   3D.
[    1.296775][    T1] [drm]   Extended Fifo.
[    1.297775][    T1] [drm]   Multimon.
[    1.298775][    T1] [drm]   Pitchlock.
[    1.299775][    T1] [drm]   Irq mask.
[    1.300775][    T1] [drm]   Display Topology.
[    1.301776][    T1] [drm]   GMR.
[    1.302795][    T1] [drm]   Traces.
[    1.303798][    T1] [drm]   GMR2.
[    1.304776][    T1] [drm]   Screen Object 2.
[    1.305776][    T1] [drm]   Command Buffers.
[    1.306776][    T1] [drm]   Command Buffers 2.
[    1.307776][    T1] [drm]   Guest Backed Resources.
[    1.308775][    T1] [drm]   DX Features.
[    1.309797][    T1] [drm]   HP Command Queue.
[    1.310776][    T1] [drm] Capabilities2:
[    1.311776][    T1] [drm]   Grow oTable.
[    1.312775][    T1] [drm]   IntraSurface copy.
[    1.313806][    T1] [drm] Max GMR ids is 64
[    1.314780][    T1] [drm] Max number of GMR pages is 65536
[    1.315777][    T1] [drm] Max dedicated hypervisor surface memory is 0 kiB
[    1.316776][    T1] [drm] Maximum display memory size is 262144 kiB
[    1.317777][    T1] [drm] VRAM at 0xe8000000 size is 4096 kiB
[    1.318776][    T1] [drm] MMIO at 0xfe000000 size is 256 kiB
[    1.320259][    T1] [TTM] Zone  kernel: Available graphics memory: 1880776 KiB
[    1.320800][    T1] [TTM] Initializing pool allocator
[    1.321780][    T1] [TTM] Initializing DMA pool allocator
[    1.323796][    T1] [drm] Supports vblank timestamp caching Rev 2 (21.10.2013).
[    1.324816][    T1] [drm] Screen Target Display device initialized
[    1.325797][    T1] [drm] width 800
[    1.326790][    T1] [drm] height 480
[    1.327782][    T1] [drm] bpp 32
[    1.330791][    T1] [drm] Fifo max 0x00040000 min 0x00001000 cap 0x0000077f
[    1.345830][    T1] [drm] Using command buffers with DMA pool.
[    1.346834][    T1] [drm] Atomic: yes.
[    1.347825][    T1] [drm] SM4_1 support available.
[    1.364948][    T1] fbcon: svgadrmfb (fb0) is primary device
[    1.366787][    T1] Console: switching to colour frame buffer device 100x37
[    1.471079][    T1] [drm] Initialized vmwgfx 2.18.0 20200114 for 0000:00:0f.0 on minor 0

--- Bisect log ---

git bisect start ec731e516acf22ce870b735721c6f59e39d0ed44 442489c219235991de86d0277b5d859ede6d8792 v5.8 v5.7 v5.6 v5.5 v5.4 v5.3 v5.2 v5.1 v5.0 drivers/gpu/

# bad: [ec731e516acf22ce870b735721c6f59e39d0ed44] drm/ttm: ttm_bo_swapout_all doesn't use it's argument.
# good: [442489c219235991de86d0277b5d859ede6d8792] Merge tag 'timers-core-2020-08-04' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
# good: [bcf876870b95592b52519ed4aafcf9d95999bc9c] Linux 5.8
# good: [3d77e6a8804abcc0504c904bd6e5cdf3a5cf8162] Linux 5.7
# good: [7111951b8d4973bda27ff663f2cf18b663d15b48] Linux 5.6
# good: [d5226fa6dbae0569ee43ecfc08bdcd6770fc4755] Linux 5.5
# good: [219d54332a09e8d8741c1e1982f5eae56099de85] Linux 5.4
# good: [4d856f72c10ecb060868ed10ff1b1453943fc6c8] Linux 5.3
# good: [0ecfebd2b52404ae0c54a878c872bb93363ada36] Linux 5.2
# good: [e93c9c99a629c61837d5a7fc2120cd2b6c70dbdd] Linux 5.1
# good: [1c163f4c7b3f621efff9b28a47abb36f7378d783] Linux 5.0
git bisect start 'ec731e516acf22ce870b735721c6f59e39d0ed44' '442489c219235991de86d0277b5d859ede6d8792' 'v5.8' 'v5.7' 'v5.6' 'v5.5' 'v5.4' 'v5.3' 'v5.2' 'v5.1' 'v5.0' 'drivers/gpu/'
# good: [ba47d845d715a010f7b51f6f89bae32845e6acb7] Linux 5.8-rc6
git bisect good ba47d845d715a010f7b51f6f89bae32845e6acb7
# good: [429f3d24384b049925771c56b5bc2850cede958f] drm/amdgpu: asd function needs to be unloaded in suspend phase
git bisect good 429f3d24384b049925771c56b5bc2850cede958f
# bad: [4145cb541668eb48ac7d028d4e27b5f1b7378e4c] Merge tag 'drm-misc-next-2020-07-22' of git://anongit.freedesktop.org/drm/drm-misc into drm-next
git bisect bad 4145cb541668eb48ac7d028d4e27b5f1b7378e4c
# good: [90d4f99ac56b4aadf4e87871a4e9128474da259b] drm/i915/dp_mst: Clear the ACT sent flag during encoder disabling too
git bisect good 90d4f99ac56b4aadf4e87871a4e9128474da259b
# bad: [39913934e67cab214480cc95a3632696aeb8e71a] drm: amdgpu: fix common struct sg_table related issues
git bisect bad 39913934e67cab214480cc95a3632696aeb8e71a
# bad: [1d4eff87878977fde110f311c4fa123e93ba2b3d] drm/meson: add Amlogic Video FBC registers
git bisect bad 1d4eff87878977fde110f311c4fa123e93ba2b3d
# bad: [1185c406f11a49335253036feaa0169c0d174ef8] drm: panel: simple: Warn in case of incorrect bus format for LVDS panels
git bisect bad 1185c406f11a49335253036feaa0169c0d174ef8
# good: [84e543bc9d1dc550132ba25b72df28d40cc44333] drm/connector: fix minor typos in comments
git bisect good 84e543bc9d1dc550132ba25b72df28d40cc44333
# bad: [536faa450e17f32fddb1a2124e3df71a966122cd] drm: Add helper to compare edids.
git bisect bad 536faa450e17f32fddb1a2124e3df71a966122cd
# bad: [2ddef17678bc2ea1d20517dd2b4ed4aa967ffa8b] drm/ttm: make TT creation purely optional v3
git bisect bad 2ddef17678bc2ea1d20517dd2b4ed4aa967ffa8b
# good: [58e4d686d456c3e356439ae160ff4a0728940b8e] drm/ttm: cleanup ttm_mem_type_manager_func.get_node interface v3
git bisect good 58e4d686d456c3e356439ae160ff4a0728940b8e
# first bad commit: [2ddef17678bc2ea1d20517dd2b4ed4aa967ffa8b] drm/ttm: make TT creation purely optional v3


More information about the dri-devel mailing list