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=-6.0 required=3.0 tests=DKIMWL_WL_HIGH,DKIM_SIGNED, DKIM_VALID,HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI,SIGNED_OFF_BY, SPF_PASS,URIBL_BLOCKED,USER_AGENT_GIT autolearn=ham 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 97FD5C43381 for ; Fri, 22 Mar 2019 12:20:22 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 685982054F for ; Fri, 22 Mar 2019 12:20:22 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1553257222; bh=Yd4XKdz279nw0qA7eEqCnG0WpXu/VQclymmCuea5HJY=; h=From:To:Cc:Subject:Date:In-Reply-To:References:List-ID:From; b=LWwSgxb+wTfaCYBneGpS1mQSENbiLvspVVRbv8Ljim4GOJ8jNAM8vQbazt3AOmCF6 aXGIzAIr9gJP0ao1LpAuhT/5fX6YBV5RwUUyWzVaP9300yiKMqHDTzoSH4g3K1Gz+T wYWBy462Bgr6q9xPYrI5XzOHRBLUW601OgvLww/E= Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S2390723AbfCVMUV (ORCPT ); Fri, 22 Mar 2019 08:20:21 -0400 Received: from mail.kernel.org ([198.145.29.99]:59250 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S2390707AbfCVMUR (ORCPT ); Fri, 22 Mar 2019 08:20:17 -0400 Received: from localhost (83-86-89-107.cable.dynamic.v4.ziggo.nl [83.86.89.107]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPSA id 153502054F; Fri, 22 Mar 2019 12:20:15 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1553257216; bh=Yd4XKdz279nw0qA7eEqCnG0WpXu/VQclymmCuea5HJY=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=Xz6qNKm1XTVZ7KCHUCO9utTzA2vv6r2k04qPUNCMRYpwUmPSbsLQ3WldVhg1Mt8pu MASzm8O506AeBpqAN8c5QYryhqGM60/tG/X/U8/XNMt12uTow9RnO68VsdzQMcffPH JjfeSbOsTJF9IOxWk5g0PfDoGxVmZ8QW9AlLjsz0= From: Greg Kroah-Hartman To: linux-kernel@vger.kernel.org Cc: Greg Kroah-Hartman , stable@vger.kernel.org, Nicholas Piggin , Michael Ellerman Subject: [PATCH 5.0 166/238] powerpc/smp: Fix NMI IPI timeout Date: Fri, 22 Mar 2019 12:16:25 +0100 Message-Id: <20190322111308.096317512@linuxfoundation.org> X-Mailer: git-send-email 2.21.0 In-Reply-To: <20190322111258.383569278@linuxfoundation.org> References: <20190322111258.383569278@linuxfoundation.org> User-Agent: quilt/0.65 X-stable: review X-Patchwork-Hint: ignore MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org 5.0-stable review patch. If anyone has any objections, please let me know. ------------------ From: Nicholas Piggin commit 1b5fc84aba170bdfe3533396ca9662ceea1609b7 upstream. The NMI IPI timeout logic is broken, if __smp_send_nmi_ipi() times out on the first condition, delay_us will be zero which will send it into the second spin loop with no timeout so it will spin forever. Fixes: 5b73151fff63 ("powerpc: NMI IPI make NMI IPIs fully sychronous") Cc: stable@vger.kernel.org # v4.19+ Signed-off-by: Nicholas Piggin Signed-off-by: Michael Ellerman Signed-off-by: Greg Kroah-Hartman --- arch/powerpc/kernel/smp.c | 5 +++-- 1 file changed, 3 insertions(+), 2 deletions(-) --- a/arch/powerpc/kernel/smp.c +++ b/arch/powerpc/kernel/smp.c @@ -519,7 +519,7 @@ int __smp_send_nmi_ipi(int cpu, void (*f if (delay_us) { delay_us--; if (!delay_us) - break; + goto timeout; } } @@ -530,10 +530,11 @@ int __smp_send_nmi_ipi(int cpu, void (*f if (delay_us) { delay_us--; if (!delay_us) - break; + goto timeout; } } +timeout: if (!cpumask_empty(&nmi_ipi_pending_mask)) { /* Timeout waiting for CPUs to call smp_handle_nmi_ipi */ ret = 0;