>From time to time I see this on shutdown. I suspect this happens due to the device core trying to remove software nodes when it should not. [ 238.266524] ------------[ cut here ]------------ [ 238.271357] kernfs: can not remove 'dwc3.0.auto.ulpi', no directory [ 238.277919] WARNING: CPU: 1 PID: 257 at fs/kernfs/dir.c:1508 kernfs_remove_by_name_ns+0x74/0x80 [ 238.286970] Modules linked in: usb_f_eem u_ether libcomposite spi_dln2 i2c_dln2 gpio_dln2 dln2 brcmfmac brcmut il mmc_block pwm_lpss_pci pwm_lpss spi_pxa2xx_platform snd_sof_pci_intel_tng snd_sof_pci snd_sof_acpi_intel_byt s nd_sof_intel_ipc snd_sof_acpi snd_sof snd_sof_xtensa_dsp extcon_intel_mrfld spi_pxa2xx_pci intel_mrfld_adc sdhci_ pci cqhci sdhci intel_mrfld_pwrbtn mmc_core intel_soc_pmic_mrfld hci_uart btbcm btintel [ 238.325715] CPU: 1 PID: 257 Comm: init Not tainted 5.13.0-rc4+ #215 [ 238.332254] Hardware name: Intel Corporation Merrifield/BODEGA BAY, BIOS 542 2015.01.21:18.19.48 [ 238.341363] RIP: 0010:kernfs_remove_by_name_ns+0x74/0x80 [ 238.346922] Code: 69 a3 00 31 c0 5d 41 5c 41 5d c3 48 c7 c7 80 91 b8 b2 e8 0f 69 a3 00 b8 fe ff ff ff eb e7 48 c7 c7 f8 d5 7e b2 e8 3b f4 9c 00 <0f> 0b b8 fe ff ff ff eb d2 0f 1f 00 0f 1f 44 00 00 41 57 41 56 41 [ 238.366284] RSP: 0000:ffffb2be40293cf8 EFLAGS: 00010282 [ 238.371752] RAX: 0000000000000000 RBX: ffff8ca40ad78440 RCX: 00000000ffffdfff [ 238.379164] RDX: 00000000ffffdfff RSI: 00000000ffffffea RDI: 0000000000000000 [ 238.386628] RBP: ffff8ca40ad76018 R08: ffffffffb2b517a8 R09: 0000000000009ffb [ 238.394061] R10: 00000000ffffe000 R11: 3fffffffffffffff R12: ffff8ca402cecb80 [ 238.401480] R13: ffff8ca40ad78400 R14: 0000000000000000 R15: 0000000000000000 [ 238.408894] FS: 0000000000000000(0000) GS:ffff8ca43e300000(0063) knlGS:00000000f7f9a690 [ 238.417296] CS: 0010 DS: 002b ES: 002b CR0: 0000000080050033 [ 238.423284] CR2: 0000000056a400dc CR3: 0000000002f36000 CR4: 00000000001006e0 [ 238.430698] Call Trace: [ 238.433316] software_node_notify+0x7d/0x110 [ 238.437828] device_platform_notify+0x2c/0x70 [ 238.442422] device_del+0x1a9/0x3e0 [ 238.446140] device_unregister+0x16/0x60 [ 238.450279] dwc3_ulpi_exit+0x1a/0x30 [ 238.454155] dwc3_remove+0x6a/0x140 [ 238.457920] device_shutdown+0x15d/0x1c0 [ 238.462070] __do_sys_reboot.cold+0x2f/0x5b [ 238.466495] ? __free_one_page+0xc6/0x330 [ 238.470749] ? __lock_acquire.constprop.0+0x27d/0x550 [ 238.476067] ? find_held_lock+0x2b/0x80 [ 238.480124] ? switch_fpu_return+0x48/0xf0 [ 238.484464] do_int80_syscall_32+0x4e/0x90 [ 238.488785] entry_INT80_compat+0x85/0x8a [ 238.493008] RIP: 0023:0xf7f17d74 [ 238.496422] Code: 08 89 d8 5b 5e c3 53 b8 ad de e1 fe 8b 54 24 08 b9 69 19 12 28 e8 50 d5 ff ff 81 c3 10 af 06 00 53 89 c3 b8 58 00 00 00 cd 80 <5b> 3d 00 f0 ff ff 76 0e 8b 93 b4 02 00 00 f7 d8 65 89 02 83 c8 ff [ 238.515809] RSP: 002b:00000000ff92fa64 EFLAGS: 00000286 ORIG_RAX: 0000000000000058 [ 238.523763] RAX: ffffffffffffffda RBX: 00000000fee1dead RCX: 0000000028121969 [ 238.531228] RDX: 0000000001234567 RSI: 000000000000000f RDI: 00000000566701a0 [ 238.538642] RBP: 00000000566701a0 R08: 0000000000000000 R09: 0000000000000000 [ 238.546055] R10: 0000000000000000 R11: 0000000000000000 R12: 0000000000000000 [ 238.553464] R13: 0000000000000000 R14: 0000000000000000 R15: 0000000000000000 [ 238.560952] ---[ end trace 1339144ac23765f6 ]--- [ 238.566393] ------------[ cut here ]------------ [ 238.571290] refcount_t: underflow; use-after-free. [ 238.576360] WARNING: CPU: 0 PID: 257 at lib/refcount.c:28 refcount_warn_saturate+0xa6/0xf0 ... -- With Best Regards, Andy Shevchenko