linux/arch/riscv/lib
Guo Ren ee55ff803b
riscv: Add support for function error injection
Inspired by the commit 42d038c4fb ("arm64: Add support for function
error injection"), this patch supports function error injection for
riscv.

This patch mainly support two functions: one is regs_set_return_value()
which is used to overwrite the return value; the another function is
override_function_with_return() which is to override the probed
function returning and jump to its caller.

Test log:
 cd /sys/kernel/debug/fail_function
 echo sys_clone > inject
 echo 100 > probability
 echo 1 > interval
 ls /
[  313.176875] FAULT_INJECTION: forcing a failure.
[  313.176875] name fail_function, interval 1, probability 100, space 0, times 1
[  313.184357] CPU: 0 PID: 87 Comm: sh Not tainted 5.8.0-rc5-00007-g6a758cc #117
[  313.187616] Call Trace:
[  313.189100] [<ffffffe0002036b6>] walk_stackframe+0x0/0xc2
[  313.191626] [<ffffffe00020395c>] show_stack+0x40/0x4c
[  313.193927] [<ffffffe000556c60>] dump_stack+0x7c/0x96
[  313.194795] [<ffffffe0005522e8>] should_fail+0x140/0x142
[  313.195923] [<ffffffe000299ffc>] fei_kprobe_handler+0x2c/0x5a
[  313.197687] [<ffffffe0009e2ec4>] kprobe_breakpoint_handler+0xb4/0x18a
[  313.200054] [<ffffffe00020357e>] do_trap_break+0x36/0xca
[  313.202147] [<ffffffe000201bca>] ret_from_exception+0x0/0xc
[  313.204556] [<ffffffe000201bbc>] ret_from_syscall+0x0/0x2
-sh: can't fork: Invalid argument

Signed-off-by: Guo Ren <guoren@linux.alibaba.com>
Reviewed-by: Masami Hiramatsu <mhiramat@kernel.org>
Cc: Palmer Dabbelt <palmerdabbelt@google.com>
Cc: Paul Walmsley <paul.walmsley@sifive.com>
Signed-off-by: Palmer Dabbelt <palmerdabbelt@google.com>
2021-01-14 15:09:09 -08:00
..
delay.c riscv: delay: use do_div() instead of __udivdi3() 2019-08-08 16:05:38 -07:00
error-inject.c riscv: Add support for function error injection 2021-01-14 15:09:09 -08:00
Makefile riscv: Add support for function error injection 2021-01-14 15:09:09 -08:00
memcpy.S riscv: Add KASAN support 2020-01-22 13:09:58 -08:00
memmove.S riscv: provide memmove implementation 2020-12-10 17:27:54 -08:00
memset.S riscv: Add KASAN support 2020-01-22 13:09:58 -08:00
tishift.S riscv: Less inefficient gcc tishift helpers (and export their symbols) 2020-01-18 19:13:41 -08:00
uaccess.S RISC-V: Stop using LOCAL for the uaccess fixups 2020-03-03 10:45:14 -08:00