Linux kernel stable tree (mirror) https://git.radix-linux.su/kernel/linux.git/atom?h=v6.12.80 2021-01-14T23:09:09+00:00 2021-01-14T23:09:09+00:00 Guo Ren guoren@linux.alibaba.com 2020-12-17T16:01:45+00:00 urn:sha1:ee55ff803b383e03d0855661d3416aa1763e54f9 Inspired by the commit 42d038c4fb00 ("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>