From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1753123AbdLBPyq (ORCPT ); Sat, 2 Dec 2017 10:54:46 -0500 Received: from omzsmtpe03.verizonbusiness.com ([199.249.25.208]:8230 "EHLO omzsmtpe03.verizonbusiness.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752977AbdLBPy3 (ORCPT ); Sat, 2 Dec 2017 10:54:29 -0500 From: alexander.levin@verizon.com Cc: Jason Baron , Linus Torvalds , Peter Zijlstra , Steven Rostedt , Thomas Gleixner , Ingo Molnar , alexander.levin@verizon.com X-Host: endeavour.tdc.vzwcorp.com To: "linux-kernel@vger.kernel.org" , "stable@vger.kernel.org" Subject: [PATCH AUTOSEL for 4.4 14/20] jump_label: Invoke jump_label_test() via early_initcall() Thread-Topic: [PATCH AUTOSEL for 4.4 14/20] jump_label: Invoke jump_label_test() via early_initcall() Thread-Index: AQHTa4Wg6XSNn5My60+3N40omrPFEw== Date: Sat, 2 Dec 2017 15:52:59 +0000 Message-ID: <20171202155243.7774-14-alexander.levin@verizon.com> References: <20171202155243.7774-1-alexander.levin@verizon.com> In-Reply-To: <20171202155243.7774-1-alexander.levin@verizon.com> Accept-Language: en-US Content-Language: en-US X-MS-Has-Attach: X-MS-TNEF-Correlator: x-ms-exchange-messagesentrepresentingtype: 1 x-ms-exchange-transport-fromentityheader: Hosted x-originating-ip: [10.144.60.250] Content-Type: text/plain; charset="iso-8859-1" MIME-Version: 1.0 Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Transfer-Encoding: 8bit X-MIME-Autoconverted: from quoted-printable to 8bit by nfs id vB2FugbD018400 From: Jason Baron [ Upstream commit 92ee46efeb505ead3ab06d3c5ce695637ed5f152 ] Fengguang Wu reported that running the rcuperf test during boot can cause the jump_label_test() to hit a WARN_ON(). The issue is that the core jump label code relies on kernel_text_address() to detect when it can no longer update branches that may be contained in __init sections. The kernel_text_address() in turn assumes that if the system_state variable is greter than or equal to SYSTEM_RUNNING then __init sections are no longer valid (since the assumption is that they have been freed). However, when rcuperf is setup to run in early boot it can call kernel_power_off() which sets the system_state to SYSTEM_POWER_OFF. Since rcuperf initialization is invoked via a module_init(), we can make the dependency of jump_label_test() needing to complete before rcuperf explicit by calling it via early_initcall(). Reported-by: Fengguang Wu Signed-off-by: Jason Baron Acked-by: Paul E. McKenney Cc: Linus Torvalds Cc: Peter Zijlstra Cc: Steven Rostedt Cc: Thomas Gleixner Link: http://lkml.kernel.org/r/1510609727-2238-1-git-send-email-jbaron@akamai.com Signed-off-by: Ingo Molnar Signed-off-by: Sasha Levin --- kernel/jump_label.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/kernel/jump_label.c b/kernel/jump_label.c index 453ec4232852..e863b2339174 100644 --- a/kernel/jump_label.c +++ b/kernel/jump_label.c @@ -553,7 +553,7 @@ static __init int jump_label_test(void) return 0; } -late_initcall(jump_label_test); +early_initcall(jump_label_test); #endif /* STATIC_KEYS_SELFTEST */ #endif /* HAVE_JUMP_LABEL */ -- 2.11.0