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 X-Spam-Level: X-Spam-Status: No, score=-2.2 required=3.0 tests=DKIMWL_WL_HIGH,DKIM_SIGNED, DKIM_VALID,HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI,SPF_HELO_NONE, SPF_PASS,UNPARSEABLE_RELAY,URIBL_BLOCKED,USER_AGENT_SANE_2 autolearn=no autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 12532C432C0 for ; Tue, 26 Nov 2019 13:22:41 +0000 (UTC) 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 mail.kernel.org (Postfix) with ESMTPS id CAC0120727 for ; Tue, 26 Nov 2019 13:22:40 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (2048-bit key) header.d=lists.infradead.org header.i=@lists.infradead.org header.b="TSnxMAlJ"; dkim=fail reason="signature verification failed" (1024-bit key) header.d=mediatek.com header.i=@mediatek.com header.b="fTbR+yoo" DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org CAC0120727 Authentication-Results: mail.kernel.org; dmarc=fail (p=none dis=none) header.from=mediatek.com Authentication-Results: mail.kernel.org; spf=none smtp.mailfrom=linux-arm-kernel-bounces+infradead-linux-arm-kernel=archiver.kernel.org@lists.infradead.org DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=lists.infradead.org; s=bombadil.20170209; h=Sender: Content-Transfer-Encoding:Content-Type:Cc:List-Subscribe:List-Help:List-Post: List-Archive:List-Unsubscribe:List-Id:MIME-Version:References:In-Reply-To: Date:To:From:Subject:Message-ID:Reply-To:Content-ID:Content-Description: Resent-Date:Resent-From:Resent-Sender:Resent-To:Resent-Cc:Resent-Message-ID: List-Owner; bh=t+NvuNBo8OluvA3GBW/4WVekbWlDGPfm2COGFUmKBJI=; b=TSnxMAlJc26j1t BzOV2+3t/nbYPk7QU5Pl1a1UKiw4Mwpx0W66jEKuBt+C1B/H0s2H2Vwcf4KGAZYmaR4f5kVW67lDv bcMBSfdHc4QE7qdCees8+9suZ0N7YpzAkNc/MvlqECS4qLQXOzUjpMUiPutVct2o7oAPPEFlX5QxR UqBxMTVhIbZ3YZx/PEoVPb8h9jSX3zCyOwUYXCslYiu5xXo2PAfNxcIg8EKEZHS7bG4s8vWq4SZrl SCUwNEMHEPRI1YGNUK1JC0gaOmDAkgCwdxJY2dOJS2kL3//LZjwEtF/7JNxj0rIkXq7WvMHGxrUDe RDKyhADmPlza5/RlQemA==; Received: from localhost ([127.0.0.1] helo=bombadil.infradead.org) by bombadil.infradead.org with esmtp (Exim 4.92.3 #3 (Red Hat Linux)) id 1iZand-0001AG-64; Tue, 26 Nov 2019 13:22:37 +0000 Received: from mailgw02.mediatek.com ([216.200.240.185]) by bombadil.infradead.org with esmtps (Exim 4.92.3 #3 (Red Hat Linux)) id 1iZamj-00075j-5G; Tue, 26 Nov 2019 13:21:42 +0000 X-UUID: d3b3bd13d20f497fa05fe903a6ec3ebc-20191126 DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=mediatek.com; s=dk; h=Content-Transfer-Encoding:MIME-Version:Content-Type:References:In-Reply-To:Date:CC:To:From:Subject:Message-ID; bh=WlPnUjC0Phkva1NreMCotJOZ/GKrJRhduHCPYVkHaA0=; b=fTbR+yooKFztBsSCvuDvMAttoEjWpz/cVcLKPpJ0EKQDKoVquDsLw2z6NDMp4LE8xBsTaUIdyaWLDrnkeuz/7PjepOy4ZfdEqmF5PeXP9dKNECa7JVUnL5cjvKLdK8Xg6pEdDnGpD9cuvGStTSGBN/wHZNXXBlA0fvIAWj10pg0=; X-UUID: d3b3bd13d20f497fa05fe903a6ec3ebc-20191126 Received: from mtkcas66.mediatek.inc [(172.29.193.44)] by mailgw02.mediatek.com (envelope-from ) (musrelay.mediatek.com ESMTP with TLS) with ESMTP id 378892954; Tue, 26 Nov 2019 05:21:29 -0800 Received: from mtkmbs07n1.mediatek.inc (172.21.101.16) by MTKMBS62DR.mediatek.inc (172.29.94.18) with Microsoft SMTP Server (TLS) id 15.0.1395.4; Tue, 26 Nov 2019 05:11:40 -0800 Received: from mtkcas09.mediatek.inc (172.21.101.178) by mtkmbs07n1.mediatek.inc (172.21.101.16) with Microsoft SMTP Server (TLS) id 15.0.1395.4; Tue, 26 Nov 2019 21:11:27 +0800 Received: from [172.21.84.99] (172.21.84.99) by mtkcas09.mediatek.inc (172.21.101.73) with Microsoft SMTP Server id 15.0.1395.4 via Frontend Transport; Tue, 26 Nov 2019 21:12:01 +0800 Message-ID: <1574773890.12247.23.camel@mtksdccf07> Subject: Re: [PATCH 1/1] sched: panic, when call schedule with preemption disable From: Kathleen Chang To: Peter Zijlstra Date: Tue, 26 Nov 2019 21:11:30 +0800 In-Reply-To: <20191121123048.GQ4097@hirez.programming.kicks-ass.net> References: <1574323985-24193-1-git-send-email-yt.chang@mediatek.com> <20191121123048.GQ4097@hirez.programming.kicks-ass.net> X-Mailer: Evolution 3.2.3-0ubuntu6 MIME-Version: 1.0 X-MTK: N X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.8.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20191126_052141_236933_F2ACDFD3 X-CRM114-Status: UNSURE ( 7.26 ) X-CRM114-Notice: Please train this message. X-BeenThere: linux-arm-kernel@lists.infradead.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Cc: Matthias Brugger , linux-mediatek@lists.infradead.org, linux-kernel@vger.kernel.org, wsd_upstream@mediatek.com, linux-arm-kernel@lists.infradead.org Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Sender: "linux-arm-kernel" Errors-To: linux-arm-kernel-bounces+infradead-linux-arm-kernel=archiver.kernel.org@lists.infradead.org On Thu, 2019-11-21 at 13:30 +0100, Peter Zijlstra wrote: > On Thu, Nov 21, 2019 at 04:13:05PM +0800, YT Chang wrote: > > When preemption is disable, call schedule() is incorrect behavior. > > Suggest to panic directly rather than depend on panic_on_warn. > > Why!? 1. Panic directly will easily find the root cause. Call scheduling in atomic affects not only performance but also system stability. ex: Call scheduling in IRQ will result in IRQ enable after schedule() 2. A lot of warnings depend on panic_on_warn. It is not practical to set panic_on_warn=1. _______________________________________________ linux-arm-kernel mailing list linux-arm-kernel@lists.infradead.org http://lists.infradead.org/mailman/listinfo/linux-arm-kernel