FYI, we noticed the below changes on git://git.kernel.org/pub/scm/linux/kernel/git/tiwai/sound.git topic/hda-regmap commit 3103d80b8a89f1797e87d7265f9b389a0db4ccd8 ("ALSA: hda - Make snd_hda_bus_type public") +------------------------------------------------------------------+------------+------------+ | | d56db741b8 | 3103d80b8a | +------------------------------------------------------------------+------------+------------+ | boot_successes | 9 | 0 | | boot_failures | 1 | 20 | | Kernel_panic-not_syncing:Out_of_memory_and_no_killable_processes | 1 | | | kernel_BUG_at_drivers/base/driver.c | 0 | 20 | | invalid_opcode | 0 | 20 | | RIP:driver_register | 0 | 20 | | Kernel_panic-not_syncing:Fatal_exception | 0 | 20 | | backtrace:generic_driver_init | 0 | 20 | | backtrace:kernel_init_freeable | 0 | 20 | +------------------------------------------------------------------+------------+------------+ [ 26.392434] Error: Driver 'pcspkr' is already registered, aborting... [ 26.397925] ASIHPI driver 4.14.03 [ 26.403752] ------------[ cut here ]------------ [ 26.404009] kernel BUG at drivers/base/driver.c:152! [ 26.404009] invalid opcode: 0000 [#1] SMP DEBUG_PAGEALLOC [ 26.404009] Modules linked in: [ 26.404009] CPU: 0 PID: 1 Comm: swapper/0 Not tainted 4.0.0-rc2-wl-ath-00623-gf9a6235 #87 [ 26.404009] Hardware name: Bochs Bochs, BIOS Bochs 01/01/2011 [ 26.404009] task: ffff880046db0010 ti: ffff880046db4000 task.ti: ffff880046db4000 [ 26.404009] RIP: 0010:[] [] driver_register+0x13/0xcc [ 26.404009] RSP: 0000:ffff880046db7e80 EFLAGS: 00010246 [ 26.404009] RAX: ffffffff8417e100 RBX: ffff88001868fba0 RCX: ffff880049a00000 [ 26.404009] RDX: 0000000000000000 RSI: ffffffff83ba822a RDI: ffffffff8414f0c0 [ 26.404009] RBP: ffff880046db7e88 R08: 0000000000000020 R09: 000000000000ffff [ 26.404009] R10: 0000000000044e00 R11: ffffffff83838f7c R12: ffffffff84497214 [ 26.404009] R13: 0000000000000000 R14: ffffffff83e1b040 R15: 0000000000000000 [ 26.404009] FS: 0000000000000000(0000) GS:ffff880049a00000(0000) knlGS:0000000000000000 [ 26.404009] CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 [ 26.404009] CR2: 00000000ffffffff CR3: 0000000003e14000 CR4: 00000000000406f0 [ 26.404009] Stack: [ 26.404009] ffffffff82995e88 ffff880046db7e98 ffffffff8449722d ffff880046db7f08 [ 26.404009] ffffffff8100216c ffffffff83cc5100 ffffffff83cad3b8 ffff88004a26641d [ 26.404009] ffffffff83ae6b81 ffff880046db7ee8 0000000000000006 0000000000000bf2 [ 26.404009] Call Trace: [ 26.404009] [] ? __hda_codec_driver_register+0x5a/0x5c [ 26.404009] [] generic_driver_init+0x19/0x1b [ 26.404009] [] do_one_initcall+0xed/0x17b [ 26.404009] [] kernel_init_freeable+0x1ec/0x279 [ 26.404009] [] ? rest_init+0xca/0xca [ 26.404009] [] kernel_init+0xe/0xdf [ 26.404009] [] ret_from_fork+0x53/0xb0 [ 26.404009] [] ? rest_init+0xca/0xca [ 26.404009] Code: c3 eb c4 c3 0f 1f 44 00 00 55 48 8b 7f 70 48 89 e5 e8 6c 0e 70 ff 5d c3 0f 1f 44 00 00 48 8b 47 08 48 83 b8 90 00 00 00 00 75 02 <0f> 0b 55 48 89 e5 41 55 41 54 53 51 48 89 fb 48 83 78 48 00 74 [ 26.404009] RIP [] driver_register+0x13/0xcc [ 26.404009] RSP [ 26.455893] ---[ end trace b3ebfc9ba3079a8d ]--- [ 26.456677] Kernel panic - not syncing: Fatal exception Thanks, Ying Huang