Hello Dri-devel, There is yet another race condition happening with ttm objects, this time with fbdev. Please consider the following simple code that shows the problem (or email attached): https://0x0.st/ojmf.c The kernel assertion: [ 2112.472011] ---[ end trace 0000000000000000 ]--- [ 2182.118552] usb 3-2.2.1.4: reset high-speed USB device number 8 using xhci_hcd [ 2194.632197] ------------[ cut here ]------------ [ 2194.632199] WARNING: CPU: 6 PID: 383 at drivers/gpu/drm/ttm/ttm_bo_vm.c:352 0xffffffff8169c28f [ 2194.632201] CPU: 6 PID: 383 Comm: fb Tainted: G W 5.19.0-rc7+ #22 353afba44cdabdab9fdfaa6990a088718abd5d85 [ 2194.632204] Hardware name: To Be Filled By O.E.M. To Be Filled By O.E.M./X300M-STX, BIOS L1.72 10/08/2021 [ 2194.632205] RIP: 0010:0xffffffff8169c28f [ 2194.632206] Code: 48 8d ba 50 01 00 00 b8 01 00 00 00 f0 0f c1 82 50 01 00 00 85 c0 74 16 8d 50 01 09 c2 78 01 c3 be 01 00 00 00 e9 91 47 e5 ff <0f> 0b eb d2 be 02 00 00 00 e9 83 47 e5 ff 0f 1f 00 41 57 41 56 41 [ 2194.632207] RSP: 0018:ffffc90000767d30 EFLAGS: 00010287 [ 2194.632209] RAX: ffff888100a627b8 RBX: ffff888101745ec0 RCX: ffff888102285128 [ 2194.632210] RDX: ffff888102b00058 RSI: 00007f89976fb000 RDI: ffff88811031d440 [ 2194.632211] RBP: ffff88810177c800 R08: ffff888102541138 R09: ffff88811f9d95e0 [ 2194.632212] R10: ffff8887fe2fc000 R11: 0000000000000000 R12: 0000000000000000 [ 2194.632213] R13: ffff888102c5fc00 R14: ffff88811031d390 R15: ffff88811031d440 [ 2194.632213] FS: 00007f89977afb68(0000) GS:ffff8887ded80000(0000) knlGS:0000000000000000 [ 2194.632214] CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 [ 2194.632215] CR2: 00007f8994840000 CR3: 00000001047df000 CR4: 0000000000750ee0 [ 2194.632216] PKRU: 55555554 [ 2194.632217] Call Trace: [ 2194.632218] <TASK> [ 2194.632219] 0xffffffff81040d1e [ 2194.632220] 0xffffffff8104306b [ 2194.632221] 0xffffffff81043306 [ 2194.632222] ? 0xffffffff81608ae6 [ 2194.632222] 0xffffffff810437d1 [ 2194.632223] 0xffffffff81fa1884 [ 2194.632224] 0xffffffff8200006a [ 2194.632225] RIP: 0033:0x00007f8997749429 [ 2194.632226] Code: 88 00 00 00 31 c0 48 89 e5 48 89 ef e8 e0 b5 00 00 bf ff ff ff ff e8 36 7a fc ff 4c 89 e7 e8 ae bc 01 00 b8 39 00 00 00 0f 05 <48> 89 c3 85 c0 75 50 b8 ba 00 00 00 64 48 8b 14 25 00 00 00 00 0f [ 2194.632227] RSP: 002b:00007ffee0d808e0 EFLAGS: 00000246 ORIG_RAX: 0000000000000039 [ 2194.632228] RAX: ffffffffffffffda RBX: 0000000000000000 RCX: 00007f8997749429 [ 2194.632229] RDX: 0000000000000000 RSI: 0000000000000000 RDI: 00007f89977affd4 [ 2194.632230] RBP: 00007ffee0d808e0 R08: 0000000000000000 R09: 0000000000000000 [ 2194.632230] R10: 0000000000000008 R11: 0000000000000246 R12: 00007f89977affd4 [ 2194.632231] R13: 00007f89977afb9c R14: 00007ffee0d809a0 R15: 00007f89977b0a40 [ 2194.632232] </TASK> Apparently this commit does not fix it dbd0da2453c694f2f74651834d90fb280b57f151 Hardware info: 00:00.0 Host bridge: Advanced Micro Devices, Inc. [AMD] Renoir/Cezanne Root Complex 00:01.0 Host bridge: Advanced Micro Devices, Inc. [AMD] Renoir PCIe Dummy Host Bridge 00:01.1 PCI bridge: Advanced Micro Devices, Inc. [AMD] Renoir PCIe GPP Bridge 00:02.0 Host bridge: Advanced Micro Devices, Inc. [AMD] Renoir PCIe Dummy Host Bridge 00:02.3 PCI bridge: Advanced Micro Devices, Inc. [AMD] Renoir/Cezanne PCIe GPP Bridge 00:02.4 PCI bridge: Advanced Micro Devices, Inc. [AMD] Renoir/Cezanne PCIe GPP Bridge 00:08.0 Host bridge: Advanced Micro Devices, Inc. [AMD] Renoir PCIe Dummy Host Bridge 00:08.1 PCI bridge: Advanced Micro Devices, Inc. [AMD] Renoir Internal PCIe GPP Bridge to Bus 00:14.0 SMBus: Advanced Micro Devices, Inc. [AMD] FCH SMBus Controller (rev 51) 00:14.3 ISA bridge: Advanced Micro Devices, Inc. [AMD] FCH LPC Bridge (rev 51) 00:18.0 Host bridge: Advanced Micro Devices, Inc. [AMD] Cezanne Data Fabric; Function 0 00:18.1 Host bridge: Advanced Micro Devices, Inc. [AMD] Cezanne Data Fabric; Function 1 00:18.2 Host bridge: Advanced Micro Devices, Inc. [AMD] Cezanne Data Fabric; Function 2 00:18.3 Host bridge: Advanced Micro Devices, Inc. [AMD] Cezanne Data Fabric; Function 3 00:18.4 Host bridge: Advanced Micro Devices, Inc. [AMD] Cezanne Data Fabric; Function 4 00:18.5 Host bridge: Advanced Micro Devices, Inc. [AMD] Cezanne Data Fabric; Function 5 00:18.6 Host bridge: Advanced Micro Devices, Inc. [AMD] Cezanne Data Fabric; Function 6 00:18.7 Host bridge: Advanced Micro Devices, Inc. [AMD] Cezanne Data Fabric; Function 7 04:00.0 VGA compatible controller: Advanced Micro Devices, Inc. [AMD/ATI] Cezanne (rev c8) 04:00.1 Audio device: Advanced Micro Devices, Inc. [AMD/ATI] Renoir Radeon High Definition Audio Controller Kyryl