From nobody Sat Feb 7 13:05:35 2026 Received: from mgamail.intel.com (mgamail.intel.com [192.198.163.18]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 7E9BC165EF9 for ; Mon, 19 Aug 2024 14:19:56 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=192.198.163.18 ARC-Seal: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1724077198; cv=none; b=CvEw+BYvD1D4b3h7XoleRkiEbUbiEQgrHQL6fwQGBV+0KODhZGDht/lQAjaTcM32jXHPTW85LMHtPYtoDOT3+AZiAQXPjnA1V3cc0CYU8a83dVmGpzlozZovtxrsa1ldU2p/Bso/uZ1c51JHs1GwiSkFe2wHFa9EfRuuNApY1yc= ARC-Message-Signature: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1724077198; c=relaxed/simple; bh=ZY84X+naWCxZF1uB0a9Y3/UeATvV+nCtMbh5bQ77fLg=; h=From:To:Cc:Subject:Date:Message-Id:MIME-Version; b=ewIOt/A7tiI1grM2VOR70RgjUfL3Cuu7EvNIEleNDu/o0qN+GA4Cj8QKV4/4iMPyBrQ2VqRoid1WwHmcJF1hvysd0IpzBdKpQM4IIO5V5fetZ/Z4uAKuFFHtkCb3aHb5hGdYIGB++DYUxBCzeFjfKUXVMeZ1v8CZM2FmCL9zrpA= ARC-Authentication-Results: i=1; smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=intel.com; spf=pass smtp.mailfrom=intel.com; dkim=pass (2048-bit key) header.d=intel.com header.i=@intel.com header.b=mCJEEcK0; arc=none smtp.client-ip=192.198.163.18 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=intel.com Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=intel.com Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=intel.com header.i=@intel.com header.b="mCJEEcK0" DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=intel.com; i=@intel.com; q=dns/txt; s=Intel; t=1724077196; x=1755613196; h=from:to:cc:subject:date:message-id:mime-version: content-transfer-encoding; bh=ZY84X+naWCxZF1uB0a9Y3/UeATvV+nCtMbh5bQ77fLg=; b=mCJEEcK0gNXGtvk0qoquM9ssWhCHutDyntIWV7G69MuTsMII5jo4/5mv E4eDzSHMKYg5WceZnCAWF9ZROeffSnxmqcadb+HCwjdYTnU58rl4TemYy jTci+hHNcWDsy+JpNloaM9yc4czN65OpLQSYpbB6Qa80cdtOmRIjlyRo/ 5CzTrfIiUohmAbEriZAkICH6q1HAKc3ywkV4aEsGjLzh45/Wxumg/DQo5 Qf0EKbYAT2zpha0IBA4BSlveKH9e+8VhfFWeRudSbVrWcPs1TomIPzfbz WBcqUb6d8uyZsVwsyJnyaeDBpeAK4IMvAmSX2R9jNN8Alb50eMGzVz1hg w==; X-CSE-ConnectionGUID: XwrylCUBTrmSIP9W5kdkUQ== X-CSE-MsgGUID: ZdFFtsw+Q0ms8FtbQxM0TA== X-IronPort-AV: E=McAfee;i="6700,10204,11169"; a="21872801" X-IronPort-AV: E=Sophos;i="6.10,159,1719903600"; d="scan'208";a="21872801" Received: from orviesa004.jf.intel.com ([10.64.159.144]) by fmvoesa112.fm.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 19 Aug 2024 07:19:55 -0700 X-CSE-ConnectionGUID: df/vEx8pR3afJWkNqwuTww== X-CSE-MsgGUID: olgkIJfSThybBnmfEw1GiQ== X-ExtLoop1: 1 X-IronPort-AV: E=Sophos;i="6.10,159,1719903600"; d="scan'208";a="65349000" Received: from chenyu-dev.sh.intel.com ([10.239.62.107]) by orviesa004.jf.intel.com with ESMTP; 19 Aug 2024 07:19:53 -0700 From: Chen Yu To: Andrew Morton , Peter Zijlstra , Andreas Gruenbacher , Tejun Heo , Shuah Khan , "Mickael Salaun" , linux-kernel@vger.kernel.org Cc: Chen Yu , Chen Yu , kernel test robot Subject: [PATCH] kthread: fix task state in kthread worker if being frozen Date: Mon, 19 Aug 2024 22:15:51 +0800 Message-Id: <20240819141551.111610-1-yu.c.chen@intel.com> X-Mailer: git-send-email 2.25.1 Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Transfer-Encoding: quoted-printable Content-Type: text/plain; charset="utf-8" It was reported that during cpu hotplug test, the following error was triggered: do not call blocking ops when !TASK_RUNNING; state=3D1 set at kthread_work= er_fn (kernel/kthread.c:?) WARNING: CPU: 1 PID: 674 at kernel/sched/core.c:8469 __might_sleep handle_bug exc_invalid_op asm_exc_invalid_op __might_sleep __might_sleep kthread_worker_fn kthread_worker_fn kthread __cfi_kthread_worker_fn ret_from_fork __cfi_kthread ret_from_fork_asm Peter pointed out that there is a race condition when the kworker is being frozen and falls into try_to_freeze() with TASK_INTERRUPTIBLE, which triggeres the warning. Fix this by explicitly set the TASK_RUNNING before entering try_to_freeze(). Fixes: b56c0d8937e6 ("kthread: implement kthread_worker") Reported-by: kernel test robot Closes: https://lore.kernel.org/oe-lkp/202408161619.9ed8b83e-lkp@intel.com Suggested-by: Peter Zijlstra Signed-off-by: Chen Yu --- kernel/kthread.c | 6 ++++++ 1 file changed, 6 insertions(+) diff --git a/kernel/kthread.c b/kernel/kthread.c index f7be976ff88a..06ab3ada9cf1 100644 --- a/kernel/kthread.c +++ b/kernel/kthread.c @@ -848,6 +848,12 @@ int kthread_worker_fn(void *worker_ptr) } else if (!freezing(current)) schedule(); =20 + /* + * Explicitly set the running state in case we are being + * frozen and skip the schedule() above. try_to_freeze() + * expects the current task to be in the running state. + */ + __set_current_state(TASK_RUNNING); try_to_freeze(); cond_resched(); goto repeat; --=20 2.25.1