From patchwork Fri May 8 12:30:03 2020 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Greg Kroah-Hartman X-Patchwork-Id: 226061 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=-6.8 required=3.0 tests=DKIMWL_WL_HIGH, DKIM_SIGNED, DKIM_VALID, HEADER_FROM_DIFFERENT_DOMAINS, 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 C6EA2C47257 for ; Fri, 8 May 2020 13:24:35 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 9149B208CA for ; Fri, 8 May 2020 13:24:35 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1588944275; bh=4461rff/8b/jph4vSDZqmbqZ71AQJeIrJYUJcwal6GM=; h=From:To:Cc:Subject:Date:In-Reply-To:References:List-ID:From; b=0cqUuzN/EJQ8jX3iIHaxxsh8rWh+jYAfTQxB+ELL4YBi0bXFL2ytUt4G60WuciGcC Jd8OCfqP1qxUdNtsWRqlVyE333xLLKs1j4afmclybGY2fd6DcWWeVJRYEB0kyTMgxB S20WG6/5cjdD1sgejbdhckg+rXfidTUJF3pJ1Jbg= Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1727788AbgEHMg1 (ORCPT ); Fri, 8 May 2020 08:36:27 -0400 Received: from mail.kernel.org ([198.145.29.99]:49634 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1727124AbgEHMg1 (ORCPT ); Fri, 8 May 2020 08:36:27 -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 9607021974; Fri, 8 May 2020 12:36:26 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1588941387; bh=4461rff/8b/jph4vSDZqmbqZ71AQJeIrJYUJcwal6GM=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=E9qxWbxl+AMW3Ep5DwYbzeQPoVCiOOBNglpdZfO2H9H+H9L68vLLJ5pLiDqoaHXuj DyaeYdIH83r7UazFja34TW0yX6Z0qtof53wPeBhtAUTltBArLJWwO4DfesohgT/NH9 ApIvFxEPFPgw2DWUDcGUx2sp8LNx+eqObiOVWdBA= From: Greg Kroah-Hartman To: linux-kernel@vger.kernel.org Cc: Greg Kroah-Hartman , stable@vger.kernel.org, Paul Burton , linux-mips@linux-mips.org, Ralf Baechle Subject: [PATCH 4.4 012/312] MIPS: smp-cps: Stop printing EJTAG exceptions to UART Date: Fri, 8 May 2020 14:30:03 +0200 Message-Id: <20200508123125.369792501@linuxfoundation.org> X-Mailer: git-send-email 2.26.2 In-Reply-To: <20200508123124.574959822@linuxfoundation.org> References: <20200508123124.574959822@linuxfoundation.org> User-Agent: quilt/0.66 MIME-Version: 1.0 Sender: stable-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: stable@vger.kernel.org From: Paul Burton commit 6609ccdc852f7bfbfa54300dd5b3cd89eb4ced6f upstream. When CONFIG_MIPS_CPS_NS16550 is enabled, some register state is dumped to the UART when an exception is taken via the BEV on secondary cores. EJTAG exceptions are architecturally expected to be handled by the BEV even when Status.BEV is 0. This effectively means that if userland executes an sdbbp instruction on a secondary core then the kernel dumps register state to the UART even though the exception is perfectly normal & expected. Prevent this by simply not dumping information to the UART for EJTAG exceptions. Fixes: 609cf6f2291a ("MIPS: CPS: Early debug using an ns16550-compatible UART") Signed-off-by: Paul Burton Cc: linux-mips@linux-mips.org Cc: linux-kernel@vger.kernel.org Patchwork: https://patchwork.linux-mips.org/patch/12341/ Signed-off-by: Ralf Baechle Signed-off-by: Greg Kroah-Hartman --- arch/mips/kernel/cps-vec.S | 1 - 1 file changed, 1 deletion(-) --- a/arch/mips/kernel/cps-vec.S +++ b/arch/mips/kernel/cps-vec.S @@ -245,7 +245,6 @@ LEAF(excep_intex) .org 0x480 LEAF(excep_ejtag) - DUMP_EXCEP("EJTAG") PTR_LA k0, ejtag_debug_handler jr k0 nop