On Saturday 21 January 2006 02:07, Peter Jeremy wrote: > When deleting a device (using device_delete_child()), all its child > devices are recursively deleted and then device_detach() is called. > > In the case of iicsmb, this causes a panic because iicsmb_detach() > also calls device_delete_child() on the smbus child it has cached in > its softc. By this time that child has been destroyed. > > Looking at device_detach(), it appears that the solution is to create > a bus_child_detached method to inform the parent that a child is being > destroyed so it can invalidate cached pointers to that child. In > practice, there are only 5 bus_child_detached methods (isa, ed, > pccard, cbb and usb), though there are far more device types attached > as children. > > Looking at the iicsmb code, it appears that iicbb and iicsmb both > cache and explicitly delete child devices and therefore both need > bus_child_detached methods. Is this correct? Is there a simpler > alternative? Can they just call bus_generic_detach() instead and not call device_delete_child()? -- John Baldwin <jhb_at_FreeBSD.org> <>< http://www.FreeBSD.org/~jhb/ "Power Users Use the Power to Serve" = http://www.FreeBSD.orgReceived on Mon Jan 23 2006 - 20:34:03 UTC
This archive was generated by hypermail 2.4.0 : Wed May 19 2021 - 11:38:51 UTC