From patchwork Mon Mar 13 08:04:03 2023 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: "Zhuo, Qiuxu" X-Patchwork-Id: 13172047 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id 797D1C6FD1F for ; Mon, 13 Mar 2023 08:07:32 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S230203AbjCMIHb (ORCPT ); Mon, 13 Mar 2023 04:07:31 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:49808 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S229796AbjCMIHA (ORCPT ); Mon, 13 Mar 2023 04:07:00 -0400 Received: from mga06.intel.com (mga06b.intel.com [134.134.136.31]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 7D6932726; Mon, 13 Mar 2023 01:04:42 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=intel.com; i=@intel.com; q=dns/txt; s=Intel; t=1678694682; x=1710230682; h=from:to:cc:subject:date:message-id; bh=gDIv4qJwZoJtfa0NlmSgzOfssIbCR1lN3aQEVECdGbc=; b=Xdz1IslvmvmSeBFCow1Z1C8RwiNWoLArogskr9YJTzNfuqOLa7YQziEU bfMEN2+1bFe+RQeWc+++1IoHfZ0JoItyJbPfXXRTpS0qWsXUrTQXWIEos 8cYiZOmtHeOSMocjC1s1c+r8ETAPR9K01L3iXW32a9KMKJXRNhNeziEqB /Px9ZwkoS4DBGQsOPu1+I7JkiOR6lYVweVFwcp/cwr+fS8y/VlaBBTbY8 y/MICqH9qE4IL5zEuOp/mAIZijjbwovwznb6eGO3f38MGN1VS3V/Vd1UV Qv3ESVojcv7xgz+Za0bslJ6zvT7NN7M0XuOpJvffOyaXVrB/eqhZ6JLGd g==; X-IronPort-AV: E=McAfee;i="6500,9779,10647"; a="399682281" X-IronPort-AV: E=Sophos;i="5.98,256,1673942400"; d="scan'208";a="399682281" Received: from orsmga008.jf.intel.com ([10.7.209.65]) by orsmga104.jf.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 13 Mar 2023 01:04:41 -0700 X-ExtLoop1: 1 X-IronPort-AV: E=McAfee;i="6500,9779,10647"; a="708784876" X-IronPort-AV: E=Sophos;i="5.98,256,1673942400"; d="scan'208";a="708784876" Received: from qiuxu-clx.sh.intel.com ([10.239.53.105]) by orsmga008-auth.jf.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 13 Mar 2023 01:04:34 -0700 From: Qiuxu Zhuo To: "Paul E. McKenney" , Frederic Weisbecker , Joel Fernandes , Josh Triplett , Neeraj Upadhyay , Davidlohr Bueso Cc: Qiuxu Zhuo , Steven Rostedt , Mathieu Desnoyers , Lai Jiangshan , rcu@vger.kernel.org, linux-kernel@vger.kernel.org Subject: [PATCH 1/1] rcu/rcuscale: Stop kfree_scale_thread thread(s) after unloading rcuscale Date: Mon, 13 Mar 2023 16:04:03 +0800 Message-Id: <20230313080403.89290-1-qiuxu.zhuo@intel.com> X-Mailer: git-send-email 2.17.1 Precedence: bulk List-ID: X-Mailing-List: rcu@vger.kernel.org When running the 'kfree_rcu_test' test case with commands [1] the call trace [2] was thrown. This was because the kfree_scale_thread thread(s) still run after unloading rcuscale and torture modules. Fix the call trace by invoking kfree_scale_cleanup() when removing the rcuscale module. [1] modprobe torture modprobe rcuscale kfree_rcu_test=1 // After some time rmmod rcuscale rmmod torture [2] BUG: unable to handle page fault for address: ffffffffc0601a87 #PF: supervisor instruction fetch in kernel mode #PF: error_code(0x0010) - not-present page PGD 11de4f067 P4D 11de4f067 PUD 11de51067 PMD 112f4d067 PTE 0 Oops: 0010 [#1] PREEMPT SMP NOPTI CPU: 1 PID: 1798 Comm: kfree_scale_thr Not tainted 6.3.0-rc1-rcu+ #1 Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 0.0.0 02/06/2015 RIP: 0010:0xffffffffc0601a87 Code: Unable to access opcode bytes at 0xffffffffc0601a5d. RSP: 0018:ffffb25bc2e57e18 EFLAGS: 00010297 RAX: 0000000000000000 RBX: ffffffffc061f0b6 RCX: 0000000000000000 RDX: 0000000000000000 RSI: ffffffff962fd0de RDI: ffffffff962fd0de RBP: ffffb25bc2e57ea8 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000001 R11: 0000000000000001 R12: 0000000000000000 R13: 0000000000000000 R14: 000000000000000a R15: 00000000001c1dbe FS: 0000000000000000(0000) GS:ffff921fa2200000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: ffffffffc0601a5d CR3: 000000011de4c006 CR4: 0000000000370ee0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Call Trace: ? kvfree_call_rcu+0xf0/0x3a0 ? kthread+0xf3/0x120 ? kthread_complete_and_exit+0x20/0x20 ? ret_from_fork+0x1f/0x30 Modules linked in: rfkill sunrpc ... [last unloaded: torture] CR2: ffffffffc0601a87 ---[ end trace 0000000000000000 ]--- Fixes: e6e78b004fa7 ("rcuperf: Add kfree_rcu() performance Tests") Signed-off-by: Qiuxu Zhuo Reviewed-by: Joel Fernandes (Google) --- kernel/rcu/rcuscale.c | 7 +++++++ 1 file changed, 7 insertions(+) diff --git a/kernel/rcu/rcuscale.c b/kernel/rcu/rcuscale.c index 91fb5905a008..5e580cd08c58 100644 --- a/kernel/rcu/rcuscale.c +++ b/kernel/rcu/rcuscale.c @@ -522,6 +522,8 @@ rcu_scale_print_module_parms(struct rcu_scale_ops *cur_ops, const char *tag) scale_type, tag, nrealreaders, nrealwriters, verbose, shutdown); } +static void kfree_scale_cleanup(void); + static void rcu_scale_cleanup(void) { @@ -542,6 +544,11 @@ rcu_scale_cleanup(void) if (gp_exp && gp_async) SCALEOUT_ERRSTRING("No expedited async GPs, so went with async!"); + if (kfree_rcu_test) { + kfree_scale_cleanup(); + return; + } + if (torture_cleanup_begin()) return; if (!cur_ops) {