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=-9.8 required=3.0 tests=DKIM_INVALID,DKIM_SIGNED, INCLUDES_PATCH,MAILING_LIST_MULTI,SIGNED_OFF_BY,SPF_HELO_NONE,SPF_PASS, USER_AGENT_GIT autolearn=unavailable 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 7D9C0C432C1 for ; Tue, 24 Sep 2019 17:33:25 +0000 (UTC) Received: from lists.ozlabs.org (lists.ozlabs.org [203.11.71.2]) (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 03C5D20872 for ; Tue, 24 Sep 2019 17:33:24 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=fail reason="signature verification failed" (1024-bit key) header.d=kernel.org header.i=@kernel.org header.b="CU/8tEwn" DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 03C5D20872 Authentication-Results: mail.kernel.org; dmarc=fail (p=none dis=none) header.from=kernel.org Authentication-Results: mail.kernel.org; spf=pass smtp.mailfrom=linuxppc-dev-bounces+linuxppc-dev=archiver.kernel.org@lists.ozlabs.org Received: from bilbo.ozlabs.org (lists.ozlabs.org [IPv6:2401:3900:2:1::3]) by lists.ozlabs.org (Postfix) with ESMTP id 46d7ZV69ZnzDqM5 for ; Wed, 25 Sep 2019 03:33:22 +1000 (AEST) Authentication-Results: lists.ozlabs.org; spf=pass (mailfrom) smtp.mailfrom=kernel.org (client-ip=198.145.29.99; helo=mail.kernel.org; envelope-from=sashal@kernel.org; receiver=) Authentication-Results: lists.ozlabs.org; dmarc=pass (p=none dis=none) header.from=kernel.org Authentication-Results: lists.ozlabs.org; dkim=pass (1024-bit key; unprotected) header.d=kernel.org header.i=@kernel.org header.b="CU/8tEwn"; dkim-atps=neutral Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by lists.ozlabs.org (Postfix) with ESMTPS id 46d6Vf3byszDqCs for ; Wed, 25 Sep 2019 02:44:58 +1000 (AEST) Received: from sasha-vm.mshome.net (c-73-47-72-35.hsd1.nh.comcast.net [73.47.72.35]) (using TLSv1.2 with cipher ECDHE-RSA-AES128-GCM-SHA256 (128/128 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPSA id B741C20872; Tue, 24 Sep 2019 16:44:55 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1569343496; bh=RdsNbSOkE3LWk5h3UxRp2TIjnw+1N5nQg2cMQy0ytRU=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=CU/8tEwncJKB25fxVc3mZDkxYU31DWVS9QxpECHVh/zW1YtmMT+5veRJ1onvo503x a7D+oXwV3vNazl2Eo0v79JbBuiO1nEIZ8FdfOQaV95wkI5wk4cek/zz7h2LAsrkl4F 7pXorNFx9b4niCHU085CxqnmM4DXMHTPdn+HFgqo= From: Sasha Levin To: linux-kernel@vger.kernel.org, stable@vger.kernel.org Subject: [PATCH AUTOSEL 5.3 71/87] powerpc/pseries: correctly track irq state in default idle Date: Tue, 24 Sep 2019 12:41:27 -0400 Message-Id: <20190924164144.25591-71-sashal@kernel.org> X-Mailer: git-send-email 2.20.1 In-Reply-To: <20190924164144.25591-1-sashal@kernel.org> References: <20190924164144.25591-1-sashal@kernel.org> MIME-Version: 1.0 X-stable: review X-Patchwork-Hint: Ignore Content-Transfer-Encoding: 8bit X-BeenThere: linuxppc-dev@lists.ozlabs.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: Linux on PowerPC Developers Mail List List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Cc: Nathan Lynch , linuxppc-dev@lists.ozlabs.org, Sasha Levin Errors-To: linuxppc-dev-bounces+linuxppc-dev=archiver.kernel.org@lists.ozlabs.org Sender: "Linuxppc-dev" From: Nathan Lynch [ Upstream commit 92c94dfb69e350471473fd3075c74bc68150879e ] prep_irq_for_idle() is intended to be called before entering H_CEDE (and it is used by the pseries cpuidle driver). However the default pseries idle routine does not call it, leading to mismanaged lazy irq state when the cpuidle driver isn't in use. Manifestations of this include: * Dropped IPIs in the time immediately after a cpu comes online (before it has installed the cpuidle handler), making the online operation block indefinitely waiting for the new cpu to respond. * Hitting this WARN_ON in arch_local_irq_restore(): /* * We should already be hard disabled here. We had bugs * where that wasn't the case so let's dbl check it and * warn if we are wrong. Only do that when IRQ tracing * is enabled as mfmsr() can be costly. */ if (WARN_ON_ONCE(mfmsr() & MSR_EE)) __hard_irq_disable(); Call prep_irq_for_idle() from pseries_lpar_idle() and honor its result. Fixes: 363edbe2614a ("powerpc: Default arch idle could cede processor on pseries") Signed-off-by: Nathan Lynch Signed-off-by: Michael Ellerman Link: https://lore.kernel.org/r/20190910225244.25056-1-nathanl@linux.ibm.com Signed-off-by: Sasha Levin --- arch/powerpc/platforms/pseries/setup.c | 3 +++ 1 file changed, 3 insertions(+) diff --git a/arch/powerpc/platforms/pseries/setup.c b/arch/powerpc/platforms/pseries/setup.c index f5940cc71c372..63462e96cf0ee 100644 --- a/arch/powerpc/platforms/pseries/setup.c +++ b/arch/powerpc/platforms/pseries/setup.c @@ -316,6 +316,9 @@ static void pseries_lpar_idle(void) * low power mode by ceding processor to hypervisor */ + if (!prep_irq_for_idle()) + return; + /* Indicate to hypervisor that we are idle. */ get_lppaca()->idle = 1; -- 2.20.1