Hi, When booting a rockpro64-v2 with a kernel built from commit dd81e1c7d5fb ("Merge tag 'powerpc-5.17-2' of git://git.kernel.org/pub/scm/linux/kernel/git/powerpc/linux"), which was the latest commit when ran the tests, I encounter a NULL pointer dereference: [..] [ 0.000000] Kernel command line: root=PARTUUID=7f4aab92-69d8-47f3-be10-624da40a71f9 rw earlycon rootwait [..] [ 3.396944] hub 7-0:1.0: USB hub found [ 3.397575] hub 7-0:1.0: 1 port detected [ 3.406086] ohci-platform fe3e0000.usb: Generic Platform OHCI controller [ 3.406932] ohci-platform fe3e0000.usb: new USB bus registered, assigned bus number 8 [ 3.408530] ohci-platform fe3e0000.usb: irq 38, io mem 0xfe3e0000 [ 3.476869] hub 8-0:1.0: USB hub found [ 3.477501] hub 8-0:1.0: 1 port detected [ 3.483278] rk808 0-001b: chip id: 0x0 [ 3.498495] random: fast init done [ 3.509322] rk808-regulator rk808-regulator: there is no dvs0 gpio [ 3.510143] rk808-regulator rk808-regulator: there is no dvs1 gpio [ 3.569278] OF: graph: no port node found in /i2c@ff3d0000/typec-portc@22 [ 3.573471] Unable to handle kernel NULL pointer dereference at virtual address 0000000000000000 [ 3.574466] Mem abort info: [ 3.574800] ESR = 0x96000004 [ 3.575163] EC = 0x25: DABT (current EL), IL = 32 bits [ 3.575770] SET = 0, FnV = 0 [ 3.576204] EA = 0, S1PTW = 0 [ 3.576580] FSC = 0x04: level 0 translation fault [ 3.577140] Data abort info: [ 3.577482] ISV = 0, ISS = 0x00000004 [ 3.577927] CM = 0, WnR = 0 [ 3.578279] [0000000000000000] user address but active_mm is swapper [ 3.579065] Internal error: Oops: 96000004 [#1] PREEMPT SMP [ 3.579586] Modules linked in: [ 3.579880] CPU: 5 PID: 7 Comm: kworker/u12:0 Not tainted 5.16.0-rc6-00081-g730b49aac426 #244 [ 3.580667] Hardware name: Pine64 RockPro64 v2.0 (DT) [ 3.581135] Workqueue: events_unbound deferred_probe_work_func [ 3.581689] pstate: 60000005 (nZCv daif -PAN -UAO -TCO -DIT -SSBS BTYPE=--) [ 3.582335] pc : component_master_add_with_match+0x20/0xfc [ 3.582850] lr : typec_link_ports+0x58/0x8c [ 3.583244] sp : ffff800013093980 [ 3.583553] x29: ffff800013093980 x28: ffff80001212b000 x27: ffff00000041d00d [ 3.584223] x26: ffff0000063e85e0 x25: ffff800012fcb290 x24: ffff000001386820 [ 3.584891] x23: ffff000006c2e808 x22: ffff800011416670 x21: ffff000006c2e808 [ 3.585558] x20: 0000000000000000 x19: ffff000006c2e800 x18: ffffffffffffffff [ 3.586224] x17: 000000040044ffff x16: 00400034b5503510 x15: 0000000000005ff9 [ 3.586890] x14: 0000000000000000 x13: 0000000000000003 x12: ffff0000063e8080 [ 3.587557] x11: 0000000000000005 x10: ffff800012c13a60 x9 : 0000000000000000 [ 3.588224] x8 : 0000200000000000 x7 : 0000000000000038 x6 : 000000000000004b [ 3.588892] x5 : 0000000000000000 x4 : ffff000000711800 x3 : ffff800010cd6390 [ 3.589558] x2 : 0000000000000000 x1 : ffff800011416670 x0 : ffff000006c2e808 [ 3.590224] Call trace: [ 3.590457] component_master_add_with_match+0x20/0xfc [ 3.590938] typec_link_ports+0x58/0x8c [ 3.591299] typec_register_port+0x1ac/0x300 [ 3.591705] tcpm_register_port+0x62c/0x90c [ 3.592099] fusb302_probe+0x260/0x430 [ 3.592453] i2c_device_probe+0x338/0x370 [ 3.592835] really_probe.part.0+0x9c/0x30c [ 3.593229] __driver_probe_device+0x98/0x144 [ 3.593639] driver_probe_device+0xc8/0x160 [ 3.594033] __device_attach_driver+0xb8/0x120 [ 3.594450] bus_for_each_drv+0x78/0xd0 [ 3.594810] __device_attach+0xd8/0x180 [ 3.595171] device_initial_probe+0x14/0x20 [ 3.595565] bus_probe_device+0x9c/0xa4 [ 3.595926] deferred_probe_work_func+0x88/0xc4 [ 3.596351] process_one_work+0x288/0x6e0 [ 3.596729] worker_thread+0x220/0x464 [ 3.597081] kthread+0x17c/0x190 [ 3.597392] ret_from_fork+0x10/0x20 [ 3.597737] Code: aa0203f4 a9025bf5 aa0003f5 aa0103f6 (a9400440) [ 3.598301] ---[ end trace 823a8d1795013b55 ]--- The full log can be found at [1]; config file can be found at [2]. All pastebins expire after 6 months. I tried bisecting the bug and the first bad commit is 730b49aac426 ("usb: typec: port-mapper: Convert to the component framework"). I tried to double check that the patch is indeed responsible by reverting it from master, but I got this build error: drivers/usb/typec/port-mapper.c: In function 'typec_link_ports': drivers/usb/typec/port-mapper.c:256:15: error: implicit declaration of function 'usb_for_each_port'; did you mean 'usb_for_each_dev'? [-Werror=implicit-function-declaration] 256 | ret = usb_for_each_port(&con->dev, each_port); | ^~~~~~~~~~~~~~~~~ | usb_for_each_dev I tried building and booting from the bad commit, and I got the same NULL pointer dereference error. When building from the last good commit (8c67d06f3fd9 ("usb: Link the ports to the connectors they are attached to")), the board boots just fine. The log when booting from the good commit can be found at [3]. I can help with debugging and testing, but I'm not familiar enough with the USB subsystem to fix it myself. [1] https://pastebin.com/w4tMNhve [2] https://pastebin.com/SiUuLeMs [3] https://pastebin.com/Pcm9xmL7 Thanks, Alex