Re: [Tarantool-patches] [PATCH luajit v3 3/3] Follow-up fix for stack overflow handling cleanup.

[Sergey Bronnikov via Tarantool-patches <tarantool-patches@dev.tarantool.org>]

Hello, Max

added testcase is passed with reverted patch

Sergey

On 11/22/23 17:35, Maksim Kokryashkin wrote:
> From: Mike Pall <mike>
>
> (cherry-picked from commit aa6b15c1a8922848bd6f596ba384824ca3fe0f5f)
>
> The stack overflow error is thrown in `lj_state_growstack` only
> if the coroutine status is `OK`, however, stack overflow can
> happen on a yielded coroutine too. This patch fixes the condition
> for status, so now the error thrown on yielded coroutines too.
>
> Maxim Kokryashkin:
> * added the description and the test for the patch
>
> Part of tarantool/tarantool#9145
> ---
>   src/lj_state.c                                |  2 +-
>   .../lj-962-premature-stack-overflow.test.c    | 23 +++++++++++++++++++
>   2 files changed, 24 insertions(+), 1 deletion(-)
>
> diff --git a/src/lj_state.c b/src/lj_state.c
> index d8a5134c..01d4901a 100644
> --- a/src/lj_state.c
> +++ b/src/lj_state.c
> @@ -126,7 +126,7 @@ void LJ_FASTCALL lj_state_growstack(lua_State *L, MSize need)
>       if (L->stacksize > LJ_STACK_MAXEX)
>         lj_err_throw(L, LUA_ERRERR);  /* Does not invoke an error handler. */
>       /* 1. We are _at_ the limit after the last growth. */
> -    if (!L->status) {  /* 2. Throw 'stack overflow'. */
> +    if (L->status < LUA_ERRRUN) {  /* 2. Throw 'stack overflow'. */
>         L->status = LUA_ERRRUN;  /* Prevent ending here again for pushed msg. */
>         lj_err_msg(L, LJ_ERR_STKOV);  /* May invoke an error handler. */
>       }
> diff --git a/test/tarantool-c-tests/lj-962-premature-stack-overflow.test.c b/test/tarantool-c-tests/lj-962-premature-stack-overflow.test.c
> index 12cb9004..461e0ccc 100644
> --- a/test/tarantool-c-tests/lj-962-premature-stack-overflow.test.c
> +++ b/test/tarantool-c-tests/lj-962-premature-stack-overflow.test.c
> @@ -24,6 +24,20 @@ static int fill_stack(lua_State *L)
>   	return 0;
>   }
>   
> +static int immediate_yield(lua_State *L)
> +{
> +	return lua_yield(L, 0);
> +}
> +
> +static int overflow_suspended_coro(lua_State *L)
> +{
> +	lua_State *newL = lua_newthread(L);
> +	lua_pushcfunction(newL, immediate_yield);
> +	lua_resume(newL, 0);
> +	fill_stack(newL);
> +	return 0;
> +}
> +
>   static int premature_stackoverflow(void *test_state)
>   {
>   	lua_State *L = test_state;
> @@ -50,12 +64,21 @@ static int stackoverflow_during_stackoverflow(void *test_state)
>   	return TEST_EXIT_SUCCESS;
>   }
>   
> +static int stackoverflow_on_suspended_coro(void *test_state)
> +{
> +	lua_State *L = test_state;
> +	int status = lua_cpcall(L, overflow_suspended_coro, NULL);
> +	assert_true(status == LUA_ERRRUN);
> +	return TEST_EXIT_SUCCESS;
> +}
> +
>   int main(void)
>   {
>   	lua_State *L = utils_lua_init();
>   	const struct test_unit tgroup[] = {
>   		test_unit_def(premature_stackoverflow),
>   		test_unit_def(stackoverflow_during_stackoverflow),
> +		test_unit_def(stackoverflow_on_suspended_coro),
>   	};
>   	const int test_result = test_run_group(tgroup, L);
>   	utils_lua_close(L);