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=-9.0 required=3.0 tests=DKIMWL_WL_HIGH,DKIM_SIGNED, DKIM_VALID,HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_PATCH,MAILING_LIST_MULTI, SIGNED_OFF_BY,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 E2CC5C04E53 for ; Wed, 15 May 2019 11:48:52 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id A77812053B for ; Wed, 15 May 2019 11:48:52 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1557920932; bh=PYIIpr7KD2zbGK2TlpSGFy1YdRRiZrztl0urGCeOIv0=; h=From:To:Cc:Subject:Date:In-Reply-To:References:List-ID:From; b=bu+tGYJLebh6ShHAhOl0iNahv1Yy6/aXSiDyQ5jgjPeMtSNOxQvowjvKX2dHfL2y8 K+bIU6MKZJDA0iiAMMMGW7jTj3lztPfQPhRYnlWjLoEByxh6O4GkQe/S/PO6n0AIck 5znlXvS6dTFsxrdBY3ZRyc4DoMu4V2N3lh2GAWKU= Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1727631AbfEOLXd (ORCPT ); Wed, 15 May 2019 07:23:33 -0400 Received: from mail.kernel.org ([198.145.29.99]:33934 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1731146AbfEOLXc (ORCPT ); Wed, 15 May 2019 07:23:32 -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 7425F206BF; Wed, 15 May 2019 11:23:31 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1557919412; bh=PYIIpr7KD2zbGK2TlpSGFy1YdRRiZrztl0urGCeOIv0=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=Qiog7j0oBpXL0jheCEGXzyPfTFxHjlGvsbAov46tktgQ6nnkFl6v3IljgF9sXXmdV qr9sJYM4i3XUfR8Zs1gAeujkMUuZelgR2cbp0Ovd/6UzYZZ97ez80N5dgiiMxf7Bzg sBDPB7F6Sov5iv3539el7YtHoDkDFX5Zvh/jFzrY= From: Greg Kroah-Hartman To: linux-kernel@vger.kernel.org Cc: Greg Kroah-Hartman , stable@vger.kernel.org, Nicholas Piggin , Michael Ellerman , Sasha Levin Subject: [PATCH 4.19 065/113] powerpc/smp: Fix NMI IPI timeout Date: Wed, 15 May 2019 12:55:56 +0200 Message-Id: <20190515090658.482728040@linuxfoundation.org> X-Mailer: git-send-email 2.21.0 In-Reply-To: <20190515090652.640988966@linuxfoundation.org> References: <20190515090652.640988966@linuxfoundation.org> User-Agent: quilt/0.66 MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit Sender: stable-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: stable@vger.kernel.org [ Upstream commit 1b5fc84aba170bdfe3533396ca9662ceea1609b7 ] 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: Sasha Levin --- arch/powerpc/kernel/smp.c | 5 +++-- 1 file changed, 3 insertions(+), 2 deletions(-) diff --git a/arch/powerpc/kernel/smp.c b/arch/powerpc/kernel/smp.c index 61c1fadbc6444..22abba5f4cf0e 100644 --- a/arch/powerpc/kernel/smp.c +++ b/arch/powerpc/kernel/smp.c @@ -499,7 +499,7 @@ int __smp_send_nmi_ipi(int cpu, void (*fn)(struct pt_regs *), u64 delay_us, bool if (delay_us) { delay_us--; if (!delay_us) - break; + goto timeout; } } @@ -510,10 +510,11 @@ int __smp_send_nmi_ipi(int cpu, void (*fn)(struct pt_regs *), u64 delay_us, bool 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; -- 2.20.1