Date: Thu, 23 Oct 2014 16:32:59 +0200 From: Hans Petter Selasky <hps@selasky.org> To: Fabian Keil <freebsd-listen@fabiankeil.de>, FreeBSD Current <freebsd-current@freebsd.org> Subject: Re: Panic after USB deadlock followed by kldunload umass.ko Message-ID: <5449119B.8090401@selasky.org> In-Reply-To: <03fafb9a.529c7f26@fabiankeil.de> References: <03fafb9a.529c7f26@fabiankeil.de>
next in thread | previous in thread | raw e-mail | index | archive | help
On 10/23/14 16:28, Fabian Keil wrote: > A few days ago a couple of usbconfig processed did not exit: > > fk@r500 ~ $sudo procstat -kk $(pgrep usbconfig) > PID TID COMM TDNAME KSTACK > 1624 100781 usbconfig - mi_switch+0xe1 sleepq_wait+0x3a _sx_xlock_hard+0x522 _sx_xlock+0x5d usbd_enum_lock+0x3a usb_ref_device+0x157 usb_open+0xbf devfs_open+0x122 VOP_OPEN_APV+0xa1 vn_open_vnode+0x234 vn_open_cred+0x351 kern_openat+0x26f amd64_syscall+0x3fb Xfast_syscall+0xfb > 1617 100779 usbconfig - mi_switch+0xe1 sleepq_wait+0x3a _sx_xlock_hard+0x522 _sx_xlock+0x5d usbd_enum_lock+0x3a usb_ref_device+0x157 usb_open+0xbf devfs_open+0x122 VOP_OPEN_APV+0xa1 vn_open_vnode+0x234 vn_open_cred+0x351 kern_openat+0x26f amd64_syscall+0x3fb Xfast_syscall+0xfb > 1615 100777 usbconfig - mi_switch+0xe1 sleepq_wait+0x3a _sx_xlock_hard+0x522 _sx_xlock+0x5d usbd_enum_lock+0x3a usb_ref_device+0x157 usb_open+0xbf devfs_open+0x122 VOP_OPEN_APV+0xa1 vn_open_vnode+0x234 vn_open_cred+0x351 kern_openat+0x26f amd64_syscall+0x3fb Xfast_syscall+0xfb > 1601 100774 usbconfig - mi_switch+0xe1 sleepq_timedwait+0x3a _sleep+0x294 pause_sbt+0xd0 usb_pause_mtx+0x85 usb_ioctl+0x3e7 devfs_ioctl_f+0x13b kern_ioctl+0x3cd sys_ioctl+0x13c amd64_syscall+0x3fb Xfast_syscall+0xfb > > kldunload umass.ko lead to a panic, dumping didn't work. > > Screenshots are available at: > http://www.fabiankeil.de/bilder/freebsd/kernel-panic-r273434-usb/ > > I've seen locked-up usbconfig processes in the past, > usually after executing a shell function that does: > > | usbconfig_output="$(sudo usbconfig -d ${device} add_quirk UQ_MSC_NO_INQUIRY)" > | [... error handling snipped ] > | usbconfig_output="$(sudo usbconfig -d ${device} reset)" > > Sometimes the second command seems to mess up the USB system. > > Fabian > Hi, USB detach is synchronous. If for example umass fails to detach, due to reference counts not reaching zero, that might be the root cause. Try to get a backtrace from the "usb_process()" processes using kgdb, and you'll see right away what is going on. Thank you! --HPS
Want to link to this message? Use this URL: <https://mail-archive.FreeBSD.org/cgi/mid.cgi?5449119B.8090401>