[PATCH 0/2] arm/arm64: Add support for function error injection

[Leo Yan]

This small patch set is to add support for function error injection;
this can be used to eanble more advanced debugging feature, e.g.
CONFIG_BPF_KPROBE_OVERRIDE.

I only tested the first patch on arm64 platform Juno-r2 with below
steps; the second patch is for arm arch, but I absent the platform
for the testing so only pass compilation.

- Enable kernel configuration:
  CONFIG_BPF_KPROBE_OVERRIDE
  CONFIG_BTRFS_FS
  CONFIG_BPF_EVENTS=y
  CONFIG_KPROBES=y
  CONFIG_KPROBE_EVENTS=y
  CONFIG_BPF_KPROBE_OVERRIDE=y
- Build samples/bpf on Juno-r2 board with Debian rootFS:
  # cd $kernel
  # make headers_install
  # make samples/bpf/ LLC=llc-7 CLANG=clang-7
- Run the sample tracex7:
  # ./tracex7 /dev/sdb1
  [ 1975.211781] BTRFS error (device (efault)): open_ctree failed
  mount: /mnt/linux-kernel/linux-cs-dev/samples/bpf/tmpmnt: mount(2) system call failed: Cannot allocate memory.


Leo Yan (2):
  arm64: Add support for function error injection
  arm: Add support for function error injection

 arch/arm/Kconfig                         |  1 +
 arch/arm/include/asm/error-injection.h   | 13 +++++++++++++
 arch/arm/include/asm/ptrace.h            |  5 +++++
 arch/arm/lib/Makefile                    |  2 ++
 arch/arm/lib/error-inject.c              | 19 +++++++++++++++++++
 arch/arm64/Kconfig                       |  1 +
 arch/arm64/include/asm/error-injection.h | 13 +++++++++++++
 arch/arm64/include/asm/ptrace.h          |  5 +++++
 arch/arm64/lib/Makefile                  |  2 ++
 arch/arm64/lib/error-inject.c            | 19 +++++++++++++++++++
 10 files changed, 80 insertions(+)
 create mode 100644 arch/arm/include/asm/error-injection.h
 create mode 100644 arch/arm/lib/error-inject.c
 create mode 100644 arch/arm64/include/asm/error-injection.h
 create mode 100644 arch/arm64/lib/error-inject.c

-- 
2.17.1