From patchwork Tue Jul 26 01:57:47 2022 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Zhouyi Zhou X-Patchwork-Id: 12928560 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 09F58C43334 for ; Tue, 26 Jul 2022 01:58:04 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S230426AbiGZB6D (ORCPT ); Mon, 25 Jul 2022 21:58:03 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:45522 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S229853AbiGZB6D (ORCPT ); Mon, 25 Jul 2022 21:58:03 -0400 Received: from mail-pf1-x434.google.com (mail-pf1-x434.google.com [IPv6:2607:f8b0:4864:20::434]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 2068A22519; Mon, 25 Jul 2022 18:58:02 -0700 (PDT) Received: by mail-pf1-x434.google.com with SMTP id b9so11993873pfp.10; Mon, 25 Jul 2022 18:58:02 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20210112; h=from:to:cc:subject:date:message-id:mime-version :content-transfer-encoding; bh=iELE13c5EAmybvD3Vh3mx4VeAxK4EXpiqxVffBI81To=; b=hH8GmYmD/tKCI/+MEIhSwd5KFqMYKkKOz1hEtp2hdShCDxhvKsknHGDpRBp8lijY7E yLnEK1GRc5eXIUi1EAEQIhzSW0Jyt3UGgu+nFT2np7RbPZQRYIqWKU8b9wcy4F6NDQyo WNLuxFvy/K6w1B+fk/tQolzjUN94Q+7VIJskLksBaE082A9kIE9iTPCX5xfrE4r9Xxt/ eh8s/ZTqFvIB/RgMeqyb0G7MzlfzwE80cmMMrDhTcJAtoWGtpt762gW/nx5DTq+/43ld T1itpR8LXvzjA3CJm/I1IjbJBk1pfW1ZGLNFPVW1SD+6lqSRQaHklBBlzgo6bzQSDHFZ jRCA== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20210112; h=x-gm-message-state:from:to:cc:subject:date:message-id:mime-version :content-transfer-encoding; bh=iELE13c5EAmybvD3Vh3mx4VeAxK4EXpiqxVffBI81To=; b=KfPmIzTqgFOXsCx83G7H2Kx8MzXmh4A4lwnAGJsWUFVb31Uqtqfh0P3Y3qwXyh69IV uXl1EPU+3DJvyXrrQgYK5qR1cavmN6YVFxonGqUYvlSTnhvIcaFjwCrbGLvzYcw+XxZT yTWcrVIYt1vRizKKLSZLvcYL23a6gjajNPwf8HqDMbCSYpZ31OH+j0JGJStlAfpmLOHB ybWLIEy3+tV5oBdMeFDaT5dfqeJqGBmljEiTaX/2oV3QFMUkAHoceZOmxDKnI3/YypPg Rv40MXcwZw5dsCCDywiiVDMU3S723ArbRUiNbqhj+F2jrJzQhUHIhT5ZE0bVQcSJHkId 1p9Q== X-Gm-Message-State: AJIora/nAF7MstDnAH8UzQPgeXKQ0LfdU/VoUEFZ+WUGqPlW3FloKymW L21Fj145HxutLti2fp13d/Y= X-Google-Smtp-Source: AGRyM1tX4TMBHZh0Kr9SwjeR5NUak/R8xzZVbqkNwX1Satxy5I0Vkzs5ymcvGmZs7wWgHJjL9C8XCQ== X-Received: by 2002:a05:6a00:1a49:b0:528:6ea0:14e2 with SMTP id h9-20020a056a001a4900b005286ea014e2mr15078153pfv.22.1658800681435; Mon, 25 Jul 2022 18:58:01 -0700 (PDT) Received: from localhost.localdomain ([194.5.48.100]) by smtp.gmail.com with ESMTPSA id p2-20020a170902780200b00168dadc7354sm9966560pll.78.2022.07.25.18.57.54 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Mon, 25 Jul 2022 18:58:00 -0700 (PDT) From: zhouzhouyi@gmail.com To: mpe@ellerman.id.au, benh@kernel.crashing.org, paulus@samba.org, frank.rowand@sony.com, robh@kernel.org, christophe.leroy@csgroup.eu, npiggin@gmail.com, nick.child@ibm.com, adobriyan@gmail.com, clg@kaod.org, linuxppc-dev@lists.ozlabs.org, linux-kernel@vger.kernel.org, lance@osuosl.org, paulmck@kernel.org, rcu@vger.kernel.org, john.ogness@linutronix.de Cc: Zhouyi Zhou Subject: [PATCH linux-next v2] powerpc: init jump label early in ppc 64 Date: Tue, 26 Jul 2022 09:57:47 +0800 Message-Id: <20220726015747.11754-1-zhouzhouyi@gmail.com> X-Mailer: git-send-email 2.25.1 MIME-Version: 1.0 Precedence: bulk List-ID: X-Mailing-List: rcu@vger.kernel.org From: Zhouyi Zhou In ppc 64, invoke jump_label_init in setup_feature_keys is too late because static key will be used in subroutine of parse_early_param which is again subroutine of early_init_devtree. So we invoke jump_label_init just before parse_early_param in early_init_devtree. Suggested-by: Michael Ellerman Signed-off-by: Zhouyi Zhou --- Dear PPC developers I found this bug when trying to do rcutorture tests in ppc VM of Open Source Lab of Oregon State University. qemu-system-ppc64 -nographic -smp cores=8,threads=1 -net none -M pseries -nodefaults -device spapr-vscsi -serial file:/home/ubuntu/linux-next/tools/testing/selftests/rcutorture/res/2022.07.19-01.18.42-torture/results-rcutorture/TREE03/console.log -m 512 -kernel /home/ubuntu/linux-next/tools/testing/selftests/rcutorture/res/2022.07.19-01.18.42-torture/results-rcutorture/TREE03/vmlinux -append "debug_boot_weak_hash panic=-1 console=ttyS0 rcupdate.rcu_cpu_stall_suppress_at_boot=1 torture.disable_onoff_at_boot rcupdate.rcu_task_stall_timeout=30000 rcutorture.onoff_interval=200 rcutorture.onoff_holdoff=30 rcutree.gp_preinit_delay=12 rcutree.gp_init_delay=3 rcutree.gp_cleanup_delay=3 rcutree.kthread_prio=2 threadirqs tree.use_softirq=0 rcutorture.n_barrier_cbs=4 rcutorture.stat_interval=15 rcutorture.shutdown_secs=420 rcutorture.test_no_idle_hz=1 rcutorture.verbose=1" console.log report following WARN: [ 0.000000][ T0] static_key_enable_cpuslocked(): static key '0xc000000002953260' used before call to jump_label_init()^M [ 0.000000][ T0] WARNING: CPU: 0 PID: 0 at kernel/jump_label.c:166 static_key_enable_cpuslocked+0xfc/0x120^M [ 0.000000][ T0] Modules linked in:^M [ 0.000000][ T0] CPU: 0 PID: 0 Comm: swapper Not tainted 5.19.0-rc5-next-20220708-dirty #131^M [ 0.000000][ T0] NIP: c00000000038068c LR: c000000000380688 CTR: c000000000186ac0^M [ 0.000000][ T0] REGS: c000000002867930 TRAP: 0700 Not tainted (5.19.0-rc5-next-20220708-dirty)^M [ 0.000000][ T0] MSR: 8000000000022003 CR: 24282224 XER: 20040000^M [ 0.000000][ T0] CFAR: 0000000000000730 IRQMASK: 1 ^M [ 0.000000][ T0] GPR00: c000000000380688 c000000002867bd0 c000000002868d00 0000000000000065 ^M [ 0.000000][ T0] GPR04: 0000000000000001 0000000000000000 0000000000000080 000000000000000d ^M [ 0.000000][ T0] GPR08: 0000000000000000 0000000000000000 c0000000027fd000 000000000000000f ^M [ 0.000000][ T0] GPR12: c000000000186ac0 c000000002082280 0000000000000003 000000000000000d ^M [ 0.000000][ T0] GPR16: 0000000002cc00d0 0000000000000000 c000000002082280 0000000000000001 ^M [ 0.000000][ T0] GPR20: c000000002080942 0000000000000000 0000000000000000 0000000000000000 ^M [ 0.000000][ T0] GPR24: 0000000000000000 c0000000010d6168 0000000000000000 c0000000020034c8 ^M [ 0.000000][ T0] GPR28: 0000002800000000 0000000000000000 c000000002080942 c000000002953260 ^M [ 0.000000][ T0] NIP [c00000000038068c] static_key_enable_cpuslocked+0xfc/0x120^M [ 0.000000][ T0] LR [c000000000380688] static_key_enable_cpuslocked+0xf8/0x120^M [ 0.000000][ T0] Call Trace:^M [ 0.000000][ T0] [c000000002867bd0] [c000000000380688] static_key_enable_cpuslocked+0xf8/0x120 (unreliable)^M [ 0.000000][ T0] [c000000002867c40] [c000000000380810] static_key_enable+0x30/0x50^M [ 0.000000][ T0] [c000000002867c70] [c000000002030314] setup_forced_irqthreads+0x28/0x40^M [ 0.000000][ T0] [c000000002867c90] [c000000002003568] do_early_param+0xa0/0x108^M [ 0.000000][ T0] [c000000002867d10] [c000000000175340] parse_args+0x290/0x4e0^M [ 0.000000][ T0] [c000000002867e10] [c000000002003c74] parse_early_options+0x48/0x5c^M [ 0.000000][ T0] [c000000002867e30] [c000000002003ce0] parse_early_param+0x58/0x84^M [ 0.000000][ T0] [c000000002867e60] [c000000002009878] early_init_devtree+0xd4/0x518^M [ 0.000000][ T0] [c000000002867f10] [c00000000200aee0] early_setup+0xb4/0x214^M After this fix, the WARN does not show again. Kind Regards Zhouyi -- arch/powerpc/kernel/prom.c | 7 +++++++ 1 file changed, 7 insertions(+) 2.25.1 diff --git a/arch/powerpc/kernel/prom.c b/arch/powerpc/kernel/prom.c index 1066b072db35..bfe170ed6b12 100644 --- a/arch/powerpc/kernel/prom.c +++ b/arch/powerpc/kernel/prom.c @@ -751,7 +751,13 @@ void __init early_init_devtree(void *params) early_init_dt_scan_root(); early_init_dt_scan_memory_ppc(); + /* + * As generic code authors expect to be able to use static keys + * in early_param() handlers, we initialize the static keys just + * before parsing early params (it's fine to call jump_label_init + * more than once). + */ + jump_label_init(); parse_early_param(); /* make sure we've parsed cmdline for mem= before this */ --