![[Foto: Panic after USB deadlock]](../../../bilder/freebsd/kernel-panic-r273434-usb/6672-Panic-after-USB-deadlock.jpg "6672: Panic after USB deadlock")
![[Foto: Reentered debugger after dumping]](../../../bilder/freebsd/kernel-panic-r273434-usb/6673-Reentered-debugger-after-dumping.jpg "6673: Reentered debugger after dumping")
www.fabiankeil.de/bilder/freebsd/kernel-panic-r273434-usb/
After what looks like an USB-related deadlock:
fk@r500 ~ $sudo procstat -kk $(pgrep usbconfig) PID TID COMM TDNAME KSTACK 1624 100781 usbconfig - mi_switch+0xe1 sleepq_wait+0x3a _sx_xlock_hard+0x522 _sx_xlock+0x5d usbd_enum_lock+0x3a usb_ref_device+0x157 usb_open+0xbf devfs_open+0x122 VOP_OPEN_APV+0xa1 vn_open_vnode+0x234 vn_open_cred+0x351 kern_openat+0x26f amd64_syscall+0x3fb Xfast_syscall+0xfb 1617 100779 usbconfig - mi_switch+0xe1 sleepq_wait+0x3a _sx_xlock_hard+0x522 _sx_xlock+0x5d usbd_enum_lock+0x3a usb_ref_device+0x157 usb_open+0xbf devfs_open+0x122 VOP_OPEN_APV+0xa1 vn_open_vnode+0x234 vn_open_cred+0x351 kern_openat+0x26f amd64_syscall+0x3fb Xfast_syscall+0xfb 1615 100777 usbconfig - mi_switch+0xe1 sleepq_wait+0x3a _sx_xlock_hard+0x522 _sx_xlock+0x5d usbd_enum_lock+0x3a usb_ref_device+0x157 usb_open+0xbf devfs_open+0x122 VOP_OPEN_APV+0xa1 vn_open_vnode+0x234 vn_open_cred+0x351 kern_openat+0x26f amd64_syscall+0x3fb Xfast_syscall+0xfb 1601 100774 usbconfig - mi_switch+0xe1 sleepq_timedwait+0x3a _sleep+0x294 pause_sbt+0xd0 usb_pause_mtx+0x85 usb_ioctl+0x3e7 devfs_ioctl_f+0x13b kern_ioctl+0x3cd sys_ioctl+0x13c amd64_syscall+0x3fb Xfast_syscall+0xfb
kldunload umass.ko lead to the following panic:
FreeBSD r500.local 11.0-CURRENT FreeBSD 11.0-CURRENT #666 r273164+05e3470(fk): Thu Oct 16 13:25:03 CEST 2014 fk@r500.local:/usr/obj/usr/src/sys/ZOEY amd64
At least the USB deadlock has also been seen occasionally with kernels without the number of the beast.