From patchwork Fri Feb 3 22:05:26 2023 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Josh Poimboeuf X-Patchwork-Id: 13128502 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 bombadil.infradead.org (bombadil.infradead.org [198.137.202.133]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.lore.kernel.org (Postfix) with ESMTPS id 367BAC61DA4 for ; Fri, 3 Feb 2023 22:31:41 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=lists.infradead.org; s=bombadil.20210309; h=Sender: Content-Transfer-Encoding:Content-Type:List-Subscribe:List-Help:List-Post: List-Archive:List-Unsubscribe:List-Id:MIME-Version:References:In-Reply-To: Message-Id:Date:Subject:Cc:To:From:Reply-To:Content-ID:Content-Description: Resent-Date:Resent-From:Resent-Sender:Resent-To:Resent-Cc:Resent-Message-ID: List-Owner; bh=k3Pi06cyq/YiZMl7BfHRox9i51QVveiZnAq8qBzy5WM=; b=iZEfKNmu1jTe7l i/SR+nUNaswwcZjl2xUHCDrH5Y0blLd7p5mcrNanx02xW+NkHpDVM8lNE5txhzDPKmr/nBPFEw6Z8 pXmAHkWY8/fkXUM1fQwNvTsv3ohW8L8sXqEQZBAoh8AHpj5mazuEmIcKecTTFN3sMAFxesUZj/0ED TiEMV+ceu1nHd28EJ4ztARITENgplAHKEyeFOmG35HNcXlh7vliUUhoQNWLnEJ2GiohlduMr6cyf9 xjKK3/W9iKwbqCzeAt3L6UAmcP5atgpK1ogmdbQHL0fBw9hK+HbuO8px2Bla8gocFyAypxAQHJIhY iiUuQ5LYKVdGOSLtXHFA==; Received: from localhost ([::1] helo=bombadil.infradead.org) by bombadil.infradead.org with esmtp (Exim 4.94.2 #2 (Red Hat Linux)) id 1pO4Zb-003sHz-8p; Fri, 03 Feb 2023 22:30:24 +0000 Received: from dfw.source.kernel.org ([139.178.84.217]) by bombadil.infradead.org with esmtps (Exim 4.94.2 #2 (Red Hat Linux)) id 1pO4CE-003jzL-2C for linux-arm-kernel@lists.infradead.org; Fri, 03 Feb 2023 22:06:18 +0000 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 A2E8962036; Fri, 3 Feb 2023 22:06:13 +0000 (UTC) Received: by smtp.kernel.org (Postfix) with ESMTPSA id 61D75C433A8; Fri, 3 Feb 2023 22:06:11 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1675461973; bh=Gy7oghtDbUapfyH6lmA7zeDcDutJ46pdh8WMl0cgvVU=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=cz/e4Tiq0/BvLDX93eISE4dEcCFBPucrGZqH4/s6/uvyLanSuD8oY7sBMKXuYt07K mhzTK34NA4E1JWXtyejdLqJNsro+yA1Yj3Uz502TOQTJjfQrpQWQsJNvWHGo5sndOU phtWnBDv3YdyzJc4hPNyl2ZLxgw8Kbshx78FoeWjgczSitx7GhnaXT9X29zcTpGQXi U01QFLtvja2ffq22rVz1PFTU+/uSTGm4lN21v5c1bGlJrZZQ1k+Db3jT20KJrVcazD dzlT0LcCZCfDKhnovvW6WCWz4JZBeYAV+6FJaLKMYf4o9dmDrEbEXRuAD7jpQl0uB+ MCNtPX36W5EEw== 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 17/22] x86/cpu: Make sure play_dead() doesn't return Date: Fri, 3 Feb 2023 14:05:26 -0800 Message-Id: <7bfd319e3ebf5a3e56d668bee7a3b981b22b1863.1675461757.git.jpoimboe@kernel.org> X-Mailer: git-send-email 2.39.0 In-Reply-To: References: MIME-Version: 1.0 X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.8.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20230203_140614_796999_D4D68184 X-CRM114-Status: UNSURE ( 9.81 ) X-CRM114-Notice: Please train this message. X-BeenThere: linux-arm-kernel@lists.infradead.org X-Mailman-Version: 2.1.34 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Sender: "linux-arm-kernel" Errors-To: linux-arm-kernel-bounces+linux-arm-kernel=archiver.kernel.org@lists.infradead.org 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)