diff options
author | Stefan Agner <stefan@agner.ch> | 2018-09-30 23:02:33 +0100 |
---|---|---|
committer | Greg Kroah-Hartman <gregkh@linuxfoundation.org> | 2021-12-22 09:19:03 +0100 |
commit | b182bc713942b6d7db5b66dead111892187c1919 (patch) | |
tree | f45c5f68692e18b81cefc3236c2457c5a2e4c141 /arch/arm/mm/cache-nop.S | |
parent | 3bdac6e175d2379e27fa92f645d39dc79fc46a82 (diff) |
ARM: 8800/1: use choice for kernel unwinders
commit f9b58e8c7d031b0daa5c9a9ee27f5a4028ba53ac upstream.
While in theory multiple unwinders could be compiled in, it does
not make sense in practise. Use a choice to make the unwinder
selection mutually exclusive and mandatory.
Already before this commit it has not been possible to deselect
FRAME_POINTER. Remove the obsolete comment.
Furthermore, to produce a meaningful backtrace with FRAME_POINTER
enabled the kernel needs a specific function prologue:
mov ip, sp
stmfd sp!, {fp, ip, lr, pc}
sub fp, ip, #4
To get to the required prologue gcc uses apcs and no-sched-prolog.
This compiler options are not available on clang, and clang is not
able to generate the required prologue. Make the FRAME_POINTER
config symbol depending on !clang.
Suggested-by: Arnd Bergmann <arnd@arndb.de>
Signed-off-by: Stefan Agner <stefan@agner.ch>
Reviewed-by: Arnd Bergmann <arnd@arndb.de>
Signed-off-by: Russell King <rmk+kernel@armlinux.org.uk>
Signed-off-by: Anders Roxell <anders.roxell@linaro.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Diffstat (limited to 'arch/arm/mm/cache-nop.S')
0 files changed, 0 insertions, 0 deletions