From patchwork Sun Jul 24 01:02:21 2022 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Zhouyi Zhou X-Patchwork-Id: 12927408 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 28B7BC433EF for ; Sun, 24 Jul 2022 01:02:39 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S239077AbiGXBCi (ORCPT ); Sat, 23 Jul 2022 21:02:38 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:45992 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S238762AbiGXBCh (ORCPT ); Sat, 23 Jul 2022 21:02:37 -0400 Received: from mail-pj1-x102b.google.com (mail-pj1-x102b.google.com [IPv6:2607:f8b0:4864:20::102b]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id A226A17A82; Sat, 23 Jul 2022 18:02:35 -0700 (PDT) Received: by mail-pj1-x102b.google.com with SMTP id q43-20020a17090a17ae00b001f1f67e053cso7197236pja.4; Sat, 23 Jul 2022 18:02:35 -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=CnMePAjlxfqugbwA3tp6h6RFCc5B1OEQTh1N6m+wjeE=; b=OwoWxf6q/XqRD0WQiN+4+CVfXv4K783W9L7JdqbWGvT9EkFquACP2USzwgr1BBWZcs UgFa7nkl5dwNbRGqz0+stQx+lYc/wuvHeQFSqSLwHxd8pYFSbLbfYIUH9vDKO1CR9+FW 2yvL/KayQ4QKgWJ2HIKDPNL+qTja4CjGdVdCWaOLk7ArHY44EtypiRYybXNwi/Jdr5lq S3y39XpJqiS0QSZxK1PSq0YToPR+T28HcNP83uKyGgjrlB5Ez8y8Mk3G+alrWQ43yePF 6eidm9naEOPDsCmECj5JQW+XhHh+7nf9OCIAZMrQb8rkpUvtyNyO0mk4xO71ZW0oKIgH 8VjQ== 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=CnMePAjlxfqugbwA3tp6h6RFCc5B1OEQTh1N6m+wjeE=; b=eQ5tUWh+j2yZZhV4l63uEzJ0gUzq7XAb897/aZSNS/8r30yOUPiD5TxnBp0845rASl uOOP2qX6ZKQTMgzld2oOfqBqCaqNeDTCFxGQHPuMVhYeo0h6qc/ZZafy3EnTYUVKQSDS Gbt5QpBPQuVKJKndjQG/5biQ4f/Kyqiwe0yDUqpmPMSwkUgX+IR1QhZf0giP7hMDQpEL ih/F/ANhPSFClrzVLNA3+wMKpkfhmJhPqMaomGxDK6wj2zNLC0643iLm9p+5XGUoZtUf TcRPXHd1F6AEEnisy99e7QYs4QWOE7b931OrsE1wtwwuuLXnuhXutov4k+1YwV+h4Ueu gsTw== X-Gm-Message-State: AJIora9hIrFghx3WHHRFqE9IKAL1BYfcDHhq0mWjaei+CtWxHcGuPEdn /tiGcTe45qZ8f60VDqFWVHw= X-Google-Smtp-Source: AGRyM1vzFM2UWLBfSDMyYJQbiiyXGWXRTPwC5zsCa8kurF/e71YFSJZxsOOehXI9DiAtwv2OMMtl4Q== X-Received: by 2002:a17:90a:bc1:b0:1f2:435f:94bc with SMTP id x1-20020a17090a0bc100b001f2435f94bcmr7431584pjd.5.1658624554996; Sat, 23 Jul 2022 18:02:34 -0700 (PDT) Received: from localhost.localdomain ([194.5.48.112]) by smtp.gmail.com with ESMTPSA id u17-20020a17090341d100b001677d4a9654sm6286171ple.265.2022.07.23.18.02.28 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Sat, 23 Jul 2022 18:02:34 -0700 (PDT) From: zhouzhouyi@gmail.com To: john.ogness@linutronix.de, mpe@ellerman.id.au, benh@kernel.crashing.org, paulus@samba.org, akpm@linux-foundation.org, christophe.leroy@csgroup.eu, wangkefeng.wang@huawei.com, npiggin@gmail.com, rppt@kernel.org, aneesh.kumar@linux.ibm.com, linuxppc-dev@lists.ozlabs.org, linux-kernel@vger.kernel.org, lance@osuosl.org, paulmck@kernel.org, rcu@vger.kernel.org Cc: Zhouyi Zhou Subject: [PATCH linux-next] powerpc: init jump label early in ppc 64 Date: Sun, 24 Jul 2022 09:02:21 +0800 Message-Id: <20220724010221.17371-1-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 early_init_devtree. So we can invoke jump_label_init earlier in early_setup. We can not move setup_feature_keys backward because its subroutine cpu_feature_keys_init depend on data structures initialized in early_init_devtree. 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/setup_64.c | 13 ++++++++++++- 1 file changed, 12 insertions(+), 1 deletion(-) 2.25.1 diff --git a/arch/powerpc/kernel/setup_64.c b/arch/powerpc/kernel/setup_64.c index 2b2d0b0fbb30..bf2fb76221da 100644 --- a/arch/powerpc/kernel/setup_64.c +++ b/arch/powerpc/kernel/setup_64.c @@ -365,6 +365,9 @@ void __init early_setup(unsigned long dt_ptr) udbg_printf(" -> %s(), dt_ptr: 0x%lx\n", __func__, dt_ptr); + /* Initialise jump label because subsequent calls need it */ + jump_label_init(); + /* * Do early initialization using the flattened device * tree, such as retrieving the physical memory map or @@ -394,8 +397,15 @@ void __init early_setup(unsigned long dt_ptr) /* Apply all the dynamic patching */ apply_feature_fixups(); - setup_feature_keys(); + + /* + * All the cpu/mmu_has_feature() checks take on their correct polarity + * based on the current set of CPU/MMU features. These should be done + * only after early_init_devtree. + */ + cpu_feature_keys_init(); + mmu_feature_keys_init(); + /* Initialize the hash table or TLB handling */ early_init_mmu(); --