2008/2/13, Matthew Dillon <[EMAIL PROTECTED]>: > :New submission from Michael Neumann <[EMAIL PROTECTED]>: > : > :I tried my brand new HP Compaq laptop 6710b under DragonFly, but during boo= > :ting > :the installer CD it "throws" a page fault: > : > : uhub0: 2 ports ... > : uhub0: <Intel UHCI root hub, ...> > : > : Fatal trap 12: page fault while in kernel mode > : fault virtual address =3D 0x0 > : fault code =3D supervisor write, page not present > : instruction pointer =3D 0x8:0xc04a9c5c > : stack pointer =3D 0x10:0xc25f8d38 > : frame pointer =3D 0x10:0xc25f8d48 > : code segment =3D base 0x0, limit 0xfffff, type 0x1b > : =3D DPL 0, pres 1, def32 1, gram 1 > : processor eflags =3D interrupt enabled, resume, IOPL =3D 0 > : current process =3D Idle > : current thread =3D pri 46 (CRIT) > : > : kernel: type 12, code=3D2 > : stopped at usb_add_task+0x4c: movl %edi,0(%eax)
The exception occurs in TAILQ_INSERT_HEAD(&taskq->tasks, task, next), more precisely, looking at the macro expansion, in *(&taskq->tasks)->tqh_last = task. So it looks like tqh_last is a NULL ptr which presumably means that the list head has not been initialized yet. Maybe usb_add_task() is called before usb_create_event_thread() (which initializes usb_taskq[]).
