From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from smtp43.i.mail.ru (smtp43.i.mail.ru [94.100.177.103]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by dev.tarantool.org (Postfix) with ESMTPS id 6990D4765E0 for ; Tue, 22 Dec 2020 16:09:47 +0300 (MSK) From: Sergey Kaplun Date: Tue, 22 Dec 2020 16:08:58 +0300 Message-Id: <20201222130858.16812-1-skaplun@tarantool.org> MIME-Version: 1.0 Content-Transfer-Encoding: 8bit Subject: [Tarantool-patches] [PATCH] lua: avoid panic if HOOK_GC is not active List-Id: Tarantool development patches List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , To: Igor Munkin , Sergey Ostanevich Cc: Michael Filonenko , tarantool-patches@dev.tarantool.org Panic at fiber.yield() occures inside any active hook. This is the regression from 96dbc49d097a96af5273cce2b5663db5917f4ea9 ('lua: prohibit fiber yield when GC hook is active'). This patch fixes false positive panic in cases when VM is not running a GC hook. Reported-by: Michael Filonenko Follows up #4727 Closes #5649 --- Branch: https://github.com/tarantool/tarantool/tree/skaplun/gh-5649-fix-for-debug-hook Issue: https://github.com/tarantool/tarantool/issues/5649 CI: https://gitlab.com/tarantool/tarantool/-/pipelines/233249505 src/lua/utils.c | 2 +- .../gh-5649-yield-in-debug-hook.test.lua | 25 +++++++++++++++++++ 2 files changed, 26 insertions(+), 1 deletion(-) create mode 100755 test/app-tap/gh-5649-yield-in-debug-hook.test.lua diff --git a/src/lua/utils.c b/src/lua/utils.c index 23fbdd4ad..b5a6ca5b7 100644 --- a/src/lua/utils.c +++ b/src/lua/utils.c @@ -1375,7 +1375,7 @@ void cord_on_yield(void) * earlier. As a result fiber switch is prohibited when * GC hook is active and the platform is forced to stop. */ - if (unlikely(g->hookmask & (HOOK_ACTIVE|HOOK_GC))) { + if (unlikely(g->hookmask & HOOK_GC)) { struct lua_State *L = fiber()->storage.lua.stack; assert(L != NULL); lua_pushfstring(L, "fiber %d is switched while running GC" diff --git a/test/app-tap/gh-5649-yield-in-debug-hook.test.lua b/test/app-tap/gh-5649-yield-in-debug-hook.test.lua new file mode 100755 index 000000000..9c1cca51f --- /dev/null +++ b/test/app-tap/gh-5649-yield-in-debug-hook.test.lua @@ -0,0 +1,25 @@ +#!/usr/bin/env tarantool + +local fiber = require('fiber') +local tap = require('tap') +local test = tap.test('yield-in-debug-hook') + +test:plan(2) + +-- Test that HOOK_ACTIVE is not enough to panic and +-- fiber still can use general hooks at switches. +fiber.create(function() + local old_hook, mask, count = debug.gethook() + debug.sethook(function() + fiber.yield() + end, 'c') + -- All ok if panic doesn't occure. + -- Yield before hook is set back. + debug.sethook(old_hook, mask, count) + test:ok(true) +end) +-- Return to second fiber. +fiber.yield() +test:ok(true) + +os.exit(test:check() and 0 or 1) -- 2.28.0