On Mon, Jan 16, 2023 at 07:45:05AM +1000, David Airlie wrote: > On Thu, Dec 29, 2022 at 12:58 AM Diogo Ivo <diogo.ivo@xxxxxxxxxxxxxxxxxx> wrote: > As a quick check can you try changing > > drivers/gpu/drm/nouveau/nvkm/core/firmware.c:nvkm_firmware_mem_target > from NVKM_MEM_TARGET_HOST to NVKM_MEM_TARGET_NCOH ? Hello! Applying this change breaks probing in a different way, with a bad PC=0x0. From a quick look at nvkm_falcon_load_dmem it looks like this could happen due to the .load_dmem() callback not being properly initialized. This is the kernel log I got: [ 2.010601] Unable to handle kernel NULL pointer dereference at virtual address 0000000000000000 [ 2.019436] Mem abort info: [ 2.022273] ESR = 0x0000000086000005 [ 2.026066] EC = 0x21: IABT (current EL), IL = 32 bits [ 2.031429] SET = 0, FnV = 0 [ 2.034528] EA = 0, S1PTW = 0 [ 2.037694] FSC = 0x05: level 1 translation fault [ 2.042572] [0000000000000000] user address but active_mm is swapper [ 2.048961] Internal error: Oops: 0000000086000005 [#1] SMP [ 2.054529] Modules linked in: [ 2.057582] CPU: 0 PID: 36 Comm: kworker/u8:1 Not tainted 6.2.0-rc3+ #2 [ 2.064190] Hardware name: Google Pixel C (DT) [ 2.068628] Workqueue: events_unbound deferred_probe_work_func [ 2.074463] pstate: 40000005 (nZcv daif -PAN -UAO -TCO -DIT -SSBS BTYPE=--) [ 2.081417] pc : 0x0 [ 2.083600] lr : nvkm_falcon_load_dmem+0x58/0x80 [ 2.088218] sp : ffffffc009ddb6f0 [ 2.091526] x29: ffffffc009ddb6f0 x28: ffffff808028a008 x27: ffffff8081e43c38 [ 2.098658] x26: 00000000000000ff x25: ffffff808028a0a0 x24: 0000000000000000 [ 2.105788] x23: ffffff8080c328f8 x22: 000000000000002c x21: 0000000000005fd4 [ 2.112917] x20: ffffffc009ddb76c x19: ffffff8080c328b8 x18: 0000000000000000 [ 2.120047] x17: 2e74696e695f646f x16: 6874656d5f77732f x15: 0000000000000000 [ 2.127176] x14: 0000000002f546c2 x13: 0000000000000000 x12: 00000000000001ce [ 2.134306] x11: 0000000000000001 x10: 0000000000000a90 x9 : ffffffc009ddb600 [ 2.141436] x8 : ffffff80803d19f0 x7 : ffffff80bf971180 x6 : 00000000000001b9 [ 2.148565] x5 : 0000000000000000 x4 : 0000000000000000 x3 : 000000000000002c [ 2.155693] x2 : 0000000000005fd4 x1 : ffffffc009ddb76c x0 : ffffff8080c328b8 [ 2.162822] Call trace: [ 2.165264] 0x0 [ 2.167099] gm20b_pmu_init+0x78/0xb4 [ 2.170762] nvkm_pmu_init+0x20/0x34 [ 2.174334] nvkm_subdev_init_+0x60/0x12c [ 2.178339] nvkm_subdev_init+0x60/0xa0 [ 2.182171] nvkm_device_init+0x14c/0x2a0 [ 2.186178] nvkm_udevice_init+0x60/0x9c [ 2.190097] nvkm_object_init+0x48/0x1b0 [ 2.194013] nvkm_ioctl_new+0x168/0x254 [ 2.197843] nvkm_ioctl+0xd0/0x220 [ 2.201239] nvkm_client_ioctl+0x10/0x1c [ 2.205160] nvif_object_ctor+0xf4/0x22c [ 2.209079] nvif_device_ctor+0x28/0x70 [ 2.212910] nouveau_cli_init+0x150/0x590 [ 2.216916] nouveau_drm_device_init+0x60/0x2a0 [ 2.221442] nouveau_platform_device_create+0x90/0xd0 [ 2.226489] nouveau_platform_probe+0x3c/0x9c [ 2.230841] platform_probe+0x68/0xc0 [ 2.234500] really_probe+0xbc/0x2dc [ 2.238070] __driver_probe_device+0x78/0xe0 [ 2.242334] driver_probe_device+0xd8/0x160 [ 2.246511] __device_attach_driver+0xb8/0x134 [ 2.250948] bus_for_each_drv+0x78/0xd0 [ 2.254782] __device_attach+0x9c/0x1a0 [ 2.258612] device_initial_probe+0x14/0x20 [ 2.262789] bus_probe_device+0x98/0xa0 [ 2.266619] deferred_probe_work_func+0x88/0xc0 [ 2.271142] process_one_work+0x204/0x40c [ 2.275150] worker_thread+0x230/0x450 [ 2.278894] kthread+0xc8/0xcc [ 2.281946] ret_from_fork+0x10/0x20 [ 2.285525] Code: bad PC value [ 2.288576] ---[ end trace 0000000000000000 ]--- Diogo