Hi, Sergey, thanks for the patch! Please see my comments below. Sergey On 6/25/25 13:03, Sergey Kaplun wrote: > If the signal by timer is handled outside the VM, the `g->vmstate` > equals zero. This was interpreted by the sysprof as the trace with the > corresponding number and leads to the assertion failure. > > This patch fixes that by checking this case and dumping only the host > stack outside the VM. > > Resolves tarantool/tarantool#11185 > Resolves tarantool/tarantool#11429 > --- > > Branch:https://github.com/tarantool/luajit/tree/skaplun/gh-11185-stream-trace-assert > Related issues: > *https://github.com/tarantool/tarantool/issues/11185 > *https://github.com/tarantool/tarantool/issues/11429 > > Mentinoned in the test: > *https://github.com/tarantool/tarantool/issues/10803 > > src/lj_sysprof.c | 4 +- > .../gh-11185-stream-trace-assert.test.c | 54 +++++++++++++++++++ > 2 files changed, 57 insertions(+), 1 deletion(-) > create mode 100644 test/tarantool-c-tests/gh-11185-stream-trace-assert.test.c > > diff --git a/src/lj_sysprof.c b/src/lj_sysprof.c > index cf6161a5..013df2cd 100644 > --- a/src/lj_sysprof.c > +++ b/src/lj_sysprof.c > @@ -297,7 +297,9 @@ static void sysprof_record_sample(struct sysprof *sp, siginfo_t *info) > { > global_State *g = sp->g; > uint32_t _vmstate = ~(uint32_t)(g->vmstate); > - uint32_t vmstate = _vmstate < LJ_VMST_TRACE ? _vmstate : LJ_VMST_TRACE; > + /* `g->vmstate` is 0 outside the VM. Hence, dump only the host stack. */ > + uint32_t vmstate = ~_vmstate == 0 ? LJ_VMST_INTERP : > + _vmstate < LJ_VMST_TRACE ? _vmstate : LJ_VMST_TRACE; Nested ternary operators is not convenient for reading, I would probably convert at least outer condition to if-else. Feel free to ignore. > > lj_assertX(pthread_self() == sp->thread, > "bad thread during sysprof record sample"); > diff --git a/test/tarantool-c-tests/gh-11185-stream-trace-assert.test.c b/test/tarantool-c-tests/gh-11185-stream-trace-assert.test.c > new file mode 100644 > index 00000000..c4d7ea67 > --- /dev/null > +++ b/test/tarantool-c-tests/gh-11185-stream-trace-assert.test.c > @@ -0,0 +1,54 @@ > +#include "lua.h" > +#include "lauxlib.h" > + > +/* Need for skipcond for OS and ARCH. */ > +#include "lj_arch.h" > + > +#include "test.h" > +#include "utils.h" > + > +#include > +#include > + > +/* > + * Check that there is no assertion failure during the dump of the > + * sample outside the VM. > + */ > +static int gh_11185_stream_trace_assert(void *test_state) > +{ I got the following warnings produced by compiler: [ 97%] Building C object test/tarantool-c-tests/CMakeFiles/gh-11185-stream-trace-assert.dir/gh-11185-stream-trace-assert.test.c.o /home/sergeyb/sources/MRG/tarantool/third_party/luajit/test/tarantool-c-tests/gh-11185-stream-trace-assert.test.c:17:12: warning: ‘gh_11185_stream_trace_assert’ defined but not used [-Wunused-function]    17 | static int gh_11185_stream_trace_assert(void *test_state)       |            ^~~~~~~~~~~~~~~~~~~~~~~~~~~~ In file included from /home/sergeyb/sources/MRG/tarantool/third_party/luajit/test/tarantool-c-tests/gh-11185-stream-trace-assert.test.c:8: /home/sergeyb/sources/MRG/tarantool/third_party/luajit/test/tarantool-c-tests/utils.h:34:13: warning: ‘utils_lua_close’ defined but not used [-Wunused-function]    34 | static void utils_lua_close(lua_State *L)       |             ^~~~~~~~~~~~~~~ /home/sergeyb/sources/MRG/tarantool/third_party/luajit/test/tarantool-c-tests/utils.h:17:19: warning: ‘utils_lua_init’ defined but not used [-Wunused-function]    17 | static lua_State *utils_lua_init(void)       |                   ^~~~~~~~~~~~~~ [100%] Linking C executable gh-11185-stream-trace-assert.c_test CMake config string: cmake -S . -B build -DLUAJIT_USE_VALGRIND=ON -DLUAJIT_USE_ASAN=OFF -DLUAJIT_USE_SYSMALLOC=ON -DLUAJIT_ENABLE_GC64=ON  -DLUA_USE_APICHECK=ON -DLUA_USE_ASSERT=ON -DCMAKE_BUILD_TYPE=Debug > + lua_State *L = test_state; > + (void)luaL_dostring(L, > + "misc.sysprof.start({mode = 'C', path = '/dev/null'})"); > + > + pid_t self_pid = getpid(); > + /* Dump the single sample outside the VM. */ > + kill(self_pid, SIGPROF); > + > + /* No assertion fail -- stop the profiler and exit. */ > + (void)luaL_dostring(L, "misc.sysprof.stop()"); > + return TEST_EXIT_SUCCESS; > +} > + > +int main(void) > +{ > +#if LUAJIT_USE_VALGRIND > + return skip_all("Disabled due to #10803"); > +#elif LUAJIT_DISABLE_SYSPROF > + return skip_all("Sysprof is disabled"); > +#else /* LUAJIT_DISABLE_SYSPROF */ > + if (LUAJIT_OS != LUAJIT_OS_LINUX) > + return skip_all("Sysprof is implemented for Linux only"); > + if (LUAJIT_TARGET != LUAJIT_ARCH_X86 > + && LUAJIT_TARGET != LUAJIT_ARCH_X64) > + return skip_all("Sysprof is implemented for x86_64 only"); > + > + lua_State *L = utils_lua_init(); > + > + const struct test_unit tgroup[] = { > + test_unit_def(gh_11185_stream_trace_assert) Do we really need a prefix "gh_11185_" when it is already present in the filename? I would omit it. > + }; > + const int test_result = test_run_group(tgroup, L); > + utils_lua_close(L); > + return test_result; > +#endif /* LUAJIT_DISABLE_SYSPROF */ > +}