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