Re: [Tarantool-patches] [PATCH luajit 0/2] Trace abort on FFI sandwich or mode change

[Vladislav Shpilevoy <v.shpilevoy@tarantool.org>]

Hi! Thanks for the patch!

I am getting build errors here:

Undefined symbols for architecture x86_64:
  "__Unwind_DeleteException", referenced from:
      _lj_err_unwind_dwarf in libluajit.a(lj_err.o)
  "__Unwind_GetCFA", referenced from:
      _lj_err_unwind_dwarf in libluajit.a(lj_err.o)
  "__Unwind_RaiseException", referenced from:
      _lj_err_throw in libluajit.a(lj_err.o)
  "__Unwind_SetGR", referenced from:
      _lj_err_unwind_dwarf in libluajit.a(lj_err.o)
  "__Unwind_SetIP", referenced from:
      _lj_err_unwind_dwarf in libluajit.a(lj_err.o)

I think they are not related to your patch, but
probably you know how to fix them? Did I miss a build
option? I used 'make -j'.

I saw you fixed some things requested by Sergey, but I don't
see them on the branch. Did you push the latest version? For
example, in the first commit you had a typo in the commit
message - 'whe' instead of 'when'. I still see 'whe', on github
too.

On 27/03/2020 11:47, Igor Munkin wrote:
> This series closes two issues related to the JIT machinery behaviour:
> * "FFI sandwich"(*) detection is introduced. If sandwich is detected
>   while trace recording the recording is aborted. The sandwich detected
>   while mcode execution leads to the platform panic.
> * luaJIT_setmode call is prohibited while mcode execution and leads to
>   the platform panic.
> 
> (*) The following stack mix is called FFI sandwich.
>     | Lua-FFI -> С routine -> Lua-C API -> Lua VM
>     This sort of re-entrancy is explicitly not supported by LuaJIT
>     compiler. For more info see [1].
> 
> Branch: https://github.com/tarantool/luajit/tree/imun/ffi-sandwich
> 
> [1]: https://github.com/tarantool/tarantool/issues/4427
> 
> Igor Munkin (2):
>   jit: abort trace recording and execution for C API
>   jit: abort trace execution on JIT mode change
> 
>  src/lj_api.c                             | 35 ++++++++++----
>  src/lj_dispatch.c                        |  5 ++
>  src/lj_errmsg.h                          |  2 +
>  test/gh-4427-ffi-sandwich/CMakeLists.txt |  1 +
>  test/gh-4427-ffi-sandwich/libsandwich.c  | 59 ++++++++++++++++++++++++
>  test/gh-4427-ffi-sandwich/test.lua       | 26 +++++++++++
>  test/lj-flush-on-trace/CMakeLists.txt    |  1 +
>  test/lj-flush-on-trace/libflush.c        | 31 +++++++++++++
>  test/lj-flush-on-trace/test.lua          | 25 ++++++++++
>  9 files changed, 176 insertions(+), 9 deletions(-)
>  create mode 100644 test/gh-4427-ffi-sandwich/CMakeLists.txt
>  create mode 100644 test/gh-4427-ffi-sandwich/libsandwich.c
>  create mode 100644 test/gh-4427-ffi-sandwich/test.lua
>  create mode 100644 test/lj-flush-on-trace/CMakeLists.txt
>  create mode 100644 test/lj-flush-on-trace/libflush.c
>  create mode 100644 test/lj-flush-on-trace/test.lua
>