From mboxrd@z Thu Jan 1 00:00:00 1970 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 2178EC05027 for ; Mon, 6 Feb 2023 10:13:57 +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:In-Reply-To:MIME-Version:References: Message-ID:Subject:Cc:To:From:Date:Reply-To:Content-ID:Content-Description: Resent-Date:Resent-From:Resent-Sender:Resent-To:Resent-Cc:Resent-Message-ID: List-Owner; bh=znM6Wsq6HIhWt/yeUU9uhFFvgxuf1rmAWaU2xLIOCBw=; b=BiJnaPoisWbOZa mjAnPsz/eKJbvnZqFI2tIu+NOLph+x52sgAfonDA9DPoQRg7xdtyS1QPwiZZ+o8MrHnhs3ssP2DZt OQcEKg6A/TN61iNY8hFw6oTJBMN1/XlQy98uWF4ajcNcf+J8lo6dpHvNeY1UkrQZoM4Nbp6lVF1+r u/nWlM8fwVBROPkLLDvE5FQVvlqSaXE2wryjmhmoYwV6hlflL0IsUadNzQWbPb/Phv+HMF0/SYy5f 6bxwkg7775N6WJJNiyS08Kcv7s2aVW0JmmgxRJ2f7SkKSDYAcsM+I6hwkA1okr9mktyNksDinY0ng mEYeSuhO4HqNF3bMOJPg==; Received: from localhost ([::1] helo=bombadil.infradead.org) by bombadil.infradead.org with esmtp (Exim 4.94.2 #2 (Red Hat Linux)) id 1pOyUd-0083mt-F7; Mon, 06 Feb 2023 10:12:59 +0000 Received: from foss.arm.com ([217.140.110.172]) by bombadil.infradead.org with esmtp (Exim 4.94.2 #2 (Red Hat Linux)) id 1pOyUR-0083mG-US for linux-arm-kernel@lists.infradead.org; Mon, 06 Feb 2023 10:12:49 +0000 Received: from usa-sjc-imap-foss1.foss.arm.com (unknown [10.121.207.14]) by usa-sjc-mx-foss1.foss.arm.com (Postfix) with ESMTP id AF90016F3; Mon, 6 Feb 2023 02:13:26 -0800 (PST) Received: from bogus (unknown [10.57.12.205]) by usa-sjc-imap-foss1.foss.arm.com (Postfix) with ESMTPSA id 12FBE3F71E; Mon, 6 Feb 2023 02:12:41 -0800 (PST) Date: Mon, 6 Feb 2023 10:12:39 +0000 From: Sudeep Holla To: Kazuki Cc: linux-pm@vger.kernel.org, linux-kernel@vger.kernel.org, linux-arm-kernel@lists.infradead.org, Sudeep Holla , "Rafael J. Wysocki" , Daniel Lezcano , Lorenzo Pieralisi , Hector Martin , Sven Peter , Len Brown , Pavel Machek Subject: Re: s2idle breaks on machines without cpuidle support Message-ID: <20230206101239.dret3fv65cnzpken@bogus> References: <20230204152747.drte4uitljzngdt6@kazuki-mac> MIME-Version: 1.0 Content-Disposition: inline In-Reply-To: <20230204152747.drte4uitljzngdt6@kazuki-mac> X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.8.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20230206_021248_063535_B96D7169 X-CRM114-Status: GOOD ( 17.84 ) 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: , Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Sender: "linux-arm-kernel" Errors-To: linux-arm-kernel-bounces+linux-arm-kernel=archiver.kernel.org@lists.infradead.org Hi Kazaki, On Sun, Feb 05, 2023 at 12:27:47AM +0900, Kazuki wrote: > > Hi everyone, > > s2idle is blocked on machines without proper cpuidle support here > in kernel/sched/idle.c: > > > if (cpuidle_not_available(drv, dev)) { > > tick_nohz_idle_stop_tick(); > > > default_idle_call(); > > goto exit_idle; > > } > > > /* > > * Suspend-to-idle ("s2idle") is a system state in which all user space > > * has been frozen, all I/O devices have been suspended and the only > > However, there are 2 problems with this approach: > > 1. The suspend framework does not expect this, and continues to suspend the > machine, which causes machines without proper cpuidle support to break when > suspending What do you mean by break ? More details on the observation would be helpful. > 2. Suspend actually works on ARM64 machines even without proper > cpuidle (PSCI cpuidle) since they support wfi, so the assumption here is wrong > on such machines > Sorry I am bit confused here. Your point (2) contradicts the $subject. > I'm not exactly sure how to figure this out, and my attempts have all led to an > unbootable kernel, so I've cc'ed the relevant people and hopefully we can find a > solution to this problem. > Again, since s2idle is userspace driven, I don't understand what do you mean by unbootable kernel in the context of s2idle. -- Regards, Sudeep _______________________________________________ linux-arm-kernel mailing list linux-arm-kernel@lists.infradead.org http://lists.infradead.org/mailman/listinfo/linux-arm-kernel