tree 6bd41b49614a50bd7f4bd8743da9006b926dce04
parent 9934ebb8ffb1554ad76764b6e71767378d051329
author Arnd Bergmann <arnd@arndb.de> 1307715141 +0000
committer Arnd Bergmann <arnd@arndb.de> 1317496123 +0200

ARM: always use ARM_UNWIND for thumb2 kernels

Thumb2 kernels cannot be built with frame pointers, but can use the
ARM_UNWIND feature for unwinding instead. This makes sure that all
features that rely on unwinding includeing CONFIG_LATENCYTOP and
FAULT_INJECTION_STACKTRACE_FILTER do not enable frame pointers
when the unwinder is already selected, and we always build with
the unwinder when we want a thumb2 kernel, to make sure we do not
get the frame pointers instead.

A different option would be to redefine the CONFIG_FRAME_POINTERS
option on ARM to mean builing with either frame pointers or
the unwinder, and then select which one to use based on the
CPU architecture or another user option. That would still allow
building thumb2 kernels without the unwinder but would also be
more confusing.

Signed-off-by: Arnd Bergmann <arnd@arndb.de>