FYI, we noticed the below changes on git://git.collabora.co.uk/git/user/tomeu/linux.git ordered-probing-v3 commit 240d94dae48c0e526898bb54639622ca897323c9 ("driver-core: probe dependencies before probing") +------------------------------------------------+------------+------------+ > | 19a4ff36c0 | 240d94dae4 | +------------------------------------------------+------------+------------+ > boot_successes | 13 | 0 | > boot_failures | 10 | 11 | > IP-Config:Auto-configuration_of_network_failed | 10 | | > BUG:unable_to_handle_kernel | 0 | 11 | > Oops | 0 | 11 | > EIP_is_at_strlen | 0 | 11 | > Kernel_panic-not_syncing:Fatal_exception | 0 | 11 | > backtrace:driver_register | 0 | 11 | > backtrace:acpi_processor_driver_init | 0 | 11 | > backtrace:kernel_init_freeable | 0 | 11 | +------------------------------------------------+------------+------------+ [ 3.541810] ipmi_si: Unable to find any System Interface(s) [ 3.543488] input: Power Button as /devices/LNXSYSTM:00/LNXPWRBN:00/input/input0 [ 3.545519] ACPI: Power Button [PWRF] [ 3.546656] BUG: unable to handle kernel NULL pointer dereference at (null) [ 3.548538] IP: [] strlen+0x12/0x20 [ 3.549744] *pde = 00000000 [ 3.550688] Oops: 0000 [#1] PREEMPT DEBUG_PAGEALLOC [ 3.552211] Modules linked in: [ 3.553181] CPU: 0 PID: 1 Comm: swapper Not tainted 4.2.0-rc1-next-20150709-00030-g240d94d #1 [ 3.555218] Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.7.5-20140531_083030-gandalf 04/01/2014 [ 3.557547] task: d40a0000 ti: d409c000 task.ti: d409c000 [ 3.558811] EIP: 0060:[] EFLAGS: 00010246 CPU: 0 [ 3.560095] EIP is at strlen+0x12/0x20 [ 3.561071] EAX: 00000000 EBX: d4115400 ECX: ffffffff EDX: d409de58 [ 3.562489] ESI: 00000000 EDI: 00000000 EBP: d409ddf0 ESP: d409ddec [ 3.563915] DS: 007b ES: 007b FS: 0000 GS: 0000 SS: 0068 [ 3.565173] CR0: 80050033 CR2: 00000000 CR3: 01f2a000 CR4: 00040690 [ 3.566585] Stack: [ 3.567257] 00000000 d409de0c c1491cca d409de58 d415c7f8 d415c808 d409de58 d4002b90 [ 3.570008] d409de20 c151e637 00000000 00000000 c1c0e008 d409de70 c15167f1 d409de34 [ 3.572757] c1094c5d 00000000 d409de70 c17e6140 00000000 00000001 00000000 00000000 [ 3.575508] Call Trace: [ 3.576260] [] regulator_get_dependencies+0x6a/0x130 [ 3.577621] [] fwnode_get_dependencies+0x27/0x80 [ 3.579215] [] driver_probe_device+0x5d1/0x970 [ 3.580478] [] ? preempt_count_sub+0x5d/0x60 [ 3.581713] [] ? mutex_lock_nested+0x4d0/0x5a0 [ 3.582986] [] __driver_attach+0xe9/0x100 [ 3.584169] [] ? driver_probe_device+0x970/0x970 [ 3.585469] [] bus_for_each_dev+0x58/0xa0 [ 3.586663] [] driver_attach+0x1e/0x20 [ 3.587801] [] ? driver_probe_device+0x970/0x970 [ 3.589096] [] bus_add_driver+0x287/0x400 [ 3.590339] [] driver_register+0xa4/0x170 [ 3.591535] [] ? acpi_fan_driver_init+0x11/0x11 [ 3.611636] [] acpi_processor_driver_init+0x30/0x66 [ 3.613420] [] do_one_initcall+0x222/0x2f0 [ 3.614627] [] ? acpi_fan_driver_init+0x11/0x11 [ 3.615912] [] ? parse_args+0x499/0x700 [ 3.617075] [] ? kernel_init_freeable+0xd7/0x1b9 [ 3.618376] [] kernel_init_freeable+0xf7/0x1b9 [ 3.619642] [] kernel_init+0x11/0x160 [ 3.620783] [] ? schedule_tail+0x4f/0xc0 [ 3.621968] [] ret_from_kernel_thread+0x20/0x30 [ 3.623250] [] ? rest_init+0xb0/0xb0 [ 3.624369] Code: f7 be 01 00 00 00 89 f0 48 5e 5d c3 8d b6 00 00 00 00 8d bc 27 00 00 00 00 55 89 e5 57 e8 a3 c4 43 00 b9 ff ff ff ff 89 c7 31 c0 ae 5f b8 fe ff ff ff 29 c8 5d c3 66 90 55 89 e5 e8 84 c4 43 [ 3.635364] EIP: [] strlen+0x12/0x20 SS:ESP 0068:d409ddec [ 3.637011] CR2: 0000000000000000 [ 3.637923] ---[ end trace be5768d6a3053144 ]--- [ 3.639058] Kernel panic - not syncing: Fatal exception Thanks, Ying Huang