Spotted by Dominik.

into tetrachloride.(none):/mnt/raid/src/kernel/2.5/cpufreq

already being unhashed on entry.

as we delete the entry, we can only poison the back pointer, not the
traversal pointer (rcu traversal only ever walks forward).

Make __d_drop() take this into account.

Spotted by Jeremy Fitzhardinge

into home.transmeta.com:/home/torvalds/v2.5/linux

drivers/char/pty.c converted to dynamic allocation

drivers/char/rio/rio_linux.c converted to dynamic allocation

drivers/char/epca.c converted to dynamic allocation

arch/v850/kernel/{memcons,simcons}.c converted to dynamic allocation

drivers/char/vt.c converted to dynamic allocation

arch/um/drivers/* converted to dynamic allocation

arch/cris/drivers/serial.c converted to dynamic allocation

arch/alpha/kernel/srmcons.c converted to dynamic allocation

drivers/s390/char/con3215.c converted to dynamic allocation

drivers/s390/char/sclp_tty.c converted to dynamic allocation

drivers/s390/char/tubtty.c converted to dynamic allocation

drivers/s390/net/ctctty.c converted to dynamic allocation

drivers/isdn/capi/capi.c converted to dynamic allocation

arch/mips/baget/vacserial.c converted to dynamic allocation

arch/ppc/8xx_io/uart.c converted to dynamic allocation

arch/ppc/8260_io/uart.c converted to dynamic allocation

drivers/usb/serial/usb-serial.c converted to dynamic allocation

drivers/char/ip2main.c converted to dynamic allocation

arch/mips/au1000/common/serial.c converted to dynamic allocation

arch/ia64/hp/sim/simserial.c converted to dynamic allocation

arch/ppc/4xx_io/serial_sicc.c converted to dynamic allocation

drivers/usb/class/cdc-acm.c converted to dynamic allocation

drivers/char/esp.c converted to dynamic allocation

drivers/usb/class/bluetty.c converted to dynamic allocation

drivers/isdn/i4l/isdn_tty.c converted to dynamic allocation

drivers/char/hvc_console.c converted to dynamic allocation

drivers/char/pcmcia/synclink_cs.c converted to dynamic allocation

drivers/char/synclinkmp.c converted to dynamic allocation

drivers/char/synclink.c converted to dynamic allocation