From patchwork Tue Feb 14 07:05:51 2023 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Josh Poimboeuf X-Patchwork-Id: 56716 Return-Path: Delivered-To: ouuuleilei@gmail.com Received: by 2002:adf:eb09:0:0:0:0:0 with SMTP id s9csp2811397wrn; Mon, 13 Feb 2023 23:10:31 -0800 (PST) X-Google-Smtp-Source: AK7set8QMPXdAQe+CnzJSVlZXzYnExEEh/FxoFBA5csTGuOtj+HstaygKiEwuK0d/kmQWnNOHF+F X-Received: by 2002:a17:906:6d4:b0:87a:6a63:9014 with SMTP id v20-20020a17090606d400b0087a6a639014mr1996003ejb.20.1676358630909; Mon, 13 Feb 2023 23:10:30 -0800 (PST) ARC-Seal: i=1; a=rsa-sha256; t=1676358630; cv=none; d=google.com; s=arc-20160816; b=O14nhVR2zfsJIieqYsKmjBSajkPqEI8E1wbxsIjWfAS8pkCM/h61ZnP8cq0owca/qK 33X1o6KXTB3PDETEJ6JTGJ3B3zvdnnUQofKRi0Z3lqX6cqJa0wCOVj875IxxiQyx2aBZ 2HCHmZAYo4uLJpPF/Sp1ARDNJpxihIv5kF/yByMbDgjNOUXl3XxJyYimqbxKirYWdfD9 Am1FQneKOuaXX7OQoCs+RvC7hpHD/VSV3QMCuq+x+gre2kw2ZFUd7we4m88OkuusZ8hz BK5hklBB4vN7AFMtSIaSjlzgbQULu8vDZxuMfz2mPeWIskxLEb+0ZzBWo1aghk5rwxup tJhw== ARC-Message-Signature: i=1; a=rsa-sha256; c=relaxed/relaxed; d=google.com; s=arc-20160816; h=list-id:precedence:content-transfer-encoding:mime-version :references:in-reply-to:message-id:date:subject:cc:to:from :dkim-signature; bh=8TXarIzc8qU8pMPcxxD8pX0UhCr86PFNRnbPrfFBbZE=; b=DRK2QEBDeS8wNNG4iQJhtYBxZu/TD1rCYFe9l8XBTxmJ39DM43yw9j21XbqfyaiFWQ +wAsHGHalWL+ufG/veIm5Fjvxg7AqRdxeJ8S3toxkLK1MAGHnQySnlWZfbK7hqq2YWjD Zd7y9kzA+1XPwO7rpF4AG3Mif//mfweQPg4ISsMqCwKtnq9UIxo+qWDXsfvm7NA4dDI5 tkCJfhb6vHojUBjksVnOxOJ0iDFjqXqV0Mk37eXyCJCiWotBY6i1ac7g34RFpogzywZX giMrratje2Gz6wOY4N7ggmGlUz1kgAkDcFQfBnj+rOAEl5ufJ5cKk3VSHUZAvAutZL5e FKTg== ARC-Authentication-Results: i=1; mx.google.com; dkim=pass header.i=@kernel.org header.s=k20201202 header.b=fcUSoKqU; spf=pass (google.com: domain of linux-kernel-owner@vger.kernel.org designates 2620:137:e000::1:20 as permitted sender) smtp.mailfrom=linux-kernel-owner@vger.kernel.org; dmarc=pass (p=NONE sp=NONE dis=NONE) header.from=kernel.org Received: from out1.vger.email (out1.vger.email. [2620:137:e000::1:20]) by mx.google.com with ESMTP id t27-20020a170906c39b00b00878582add5esi13707216ejz.177.2023.02.13.23.10.04; Mon, 13 Feb 2023 23:10:30 -0800 (PST) Received-SPF: pass (google.com: domain of linux-kernel-owner@vger.kernel.org designates 2620:137:e000::1:20 as permitted sender) client-ip=2620:137:e000::1:20; Authentication-Results: mx.google.com; dkim=pass header.i=@kernel.org header.s=k20201202 header.b=fcUSoKqU; spf=pass (google.com: domain of linux-kernel-owner@vger.kernel.org designates 2620:137:e000::1:20 as permitted sender) smtp.mailfrom=linux-kernel-owner@vger.kernel.org; dmarc=pass (p=NONE sp=NONE dis=NONE) header.from=kernel.org Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S231895AbjBNHJT (ORCPT + 99 others); Tue, 14 Feb 2023 02:09:19 -0500 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:51750 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S231937AbjBNHHp (ORCPT ); Tue, 14 Feb 2023 02:07:45 -0500 Received: from dfw.source.kernel.org (dfw.source.kernel.org [IPv6:2604:1380:4641:c500::1]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 80FEC18A82; Mon, 13 Feb 2023 23:07:25 -0800 (PST) Received: from smtp.kernel.org (relay.kernel.org [52.25.139.140]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by dfw.source.kernel.org (Postfix) with ESMTPS id AC6136147B; Tue, 14 Feb 2023 07:07:20 +0000 (UTC) Received: by smtp.kernel.org (Postfix) with ESMTPSA id 68B3EC433AA; Tue, 14 Feb 2023 07:07:18 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1676358440; bh=lVxYhY4OwwDPhm8BTwwcRy+JxjuJw8OgWEbHa0amaW4=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=fcUSoKqULJqLPku9lRFSHdbPaNeODYe/R1sZzjrR3VRHqcq59Tm9wERqJ6PlHQrjn 5GeWqya8mNwLITuoLWSAvRpjgR3SdVziUkPO9YsYEIi1QSukk7EUS9aKdkfWfOxlAO wYjLK997WLSPPi0UzLKNSA6lD26mGt+cEcDEsvqdQMTTD3geXcDD/U9CExxmKiegju C8HPMNKcuZCM+retZCnUY1hx60pKE2mQSPyq6ne+xt6jgv18ltv46AT4IlPKwLgjF+ KccGkJXMroepuqfZj6Fbx4rYWNFKt9XuiLi9CgivFSVeZiuhzrxK+XEv+28NZ52XHL ujubifvv+6/4A== From: Josh Poimboeuf To: linux-kernel@vger.kernel.org Cc: jgross@suse.com, richard.henderson@linaro.org, ink@jurassic.park.msu.ru, mattst88@gmail.com, linux-alpha@vger.kernel.org, linux@armlinux.org.uk, linux-arm-kernel@lists.infradead.org, catalin.marinas@arm.com, will@kernel.org, guoren@kernel.org, linux-csky@vger.kernel.org, linux-ia64@vger.kernel.org, chenhuacai@kernel.org, kernel@xen0n.name, loongarch@lists.linux.dev, f.fainelli@gmail.com, bcm-kernel-feedback-list@broadcom.com, tsbogend@alpha.franken.de, linux-mips@vger.kernel.org, jiaxun.yang@flygoat.com, mpe@ellerman.id.au, npiggin@gmail.com, christophe.leroy@csgroup.eu, linuxppc-dev@lists.ozlabs.org, ysato@users.sourceforge.jp, dalias@libc.org, linux-sh@vger.kernel.org, davem@davemloft.net, sparclinux@vger.kernel.org, tglx@linutronix.de, mingo@redhat.com, bp@alien8.de, dave.hansen@linux.intel.com, x86@kernel.org, hpa@zytor.com, chris@zankel.net, jcmvbkbc@gmail.com, linux-xtensa@linux-xtensa.org, peterz@infradead.org, juri.lelli@redhat.com, vincent.guittot@linaro.org, dietmar.eggemann@arm.com, rostedt@goodmis.org, bsegall@google.com, mgorman@suse.de, bristot@redhat.com, vschneid@redhat.com, paulmck@kernel.org Subject: [PATCH v2 17/24] x86/cpu: Make sure play_dead() doesn't return Date: Mon, 13 Feb 2023 23:05:51 -0800 Message-Id: <11e6ac1cf10f92967882926e3ac16287b50642f2.1676358308.git.jpoimboe@kernel.org> X-Mailer: git-send-email 2.39.1 In-Reply-To: References: MIME-Version: 1.0 Content-type: text/plain X-Spam-Status: No, score=-4.4 required=5.0 tests=BAYES_00,DKIMWL_WL_HIGH, DKIM_SIGNED,DKIM_VALID,DKIM_VALID_AU,DKIM_VALID_EF,RCVD_IN_DNSWL_MED, SPF_HELO_NONE,SPF_PASS autolearn=ham autolearn_force=no version=3.4.6 X-Spam-Checker-Version: SpamAssassin 3.4.6 (2021-04-09) on lindbergh.monkeyblade.net Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org X-getmail-retrieved-from-mailbox: =?utf-8?q?INBOX?= X-GMAIL-THRID: =?utf-8?q?1757789427273575886?= X-GMAIL-MSGID: =?utf-8?q?1757789427273575886?= After commit 076cbf5d2163 ("x86/xen: don't let xen_pv_play_dead() return"), play_dead() never returns. Make that more explicit with a BUG(). BUG() is preferable to unreachable() because BUG() is a more explicit failure mode and avoids undefined behavior like falling off the edge of the function into whatever code happens to be next. Signed-off-by: Josh Poimboeuf --- arch/x86/include/asm/smp.h | 1 + 1 file changed, 1 insertion(+) diff --git a/arch/x86/include/asm/smp.h b/arch/x86/include/asm/smp.h index b4dbb20dab1a..8f628e08b25a 100644 --- a/arch/x86/include/asm/smp.h +++ b/arch/x86/include/asm/smp.h @@ -96,6 +96,7 @@ static inline void __cpu_die(unsigned int cpu) static inline void play_dead(void) { smp_ops.play_dead(); + BUG(); } static inline void smp_send_reschedule(int cpu)