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=DKIMWL_WL_HIGH,DKIM_SIGNED, DKIM_VALID,HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_PATCH,MAILING_LIST_MULTI, SIGNED_OFF_BY,SPF_HELO_NONE,SPF_PASS,URIBL_BLOCKED,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 76096C433E0 for ; Fri, 19 Jun 2020 16:25:12 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 532982168B for ; Fri, 19 Jun 2020 16:25:12 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1592583912; bh=QD2dczz6KPktnBNPu/65B4VsW2BARSxk7kPZm1opUus=; h=From:To:Cc:Subject:Date:In-Reply-To:References:List-ID:From; b=ao1kve+z7cbAWhOs5wXf1z7rqYxdhtWuvQXzND0pEifYZP17GZrZnB4N6TdWjOPUx CsPt+Kg9NH8drBUHTtE09T+L0ZLv3pq8wZNcesPPo8P3NAj9NShb2AzSGeomnpZ/yu JWY5pQHSz+udYv/Gqf/jf65CR4CMNYUpkp2npjnw= Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S2390300AbgFSQZE (ORCPT ); Fri, 19 Jun 2020 12:25:04 -0400 Received: from mail.kernel.org ([198.145.29.99]:53156 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S2390285AbgFSO5o (ORCPT ); Fri, 19 Jun 2020 10:57:44 -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 307D321852; Fri, 19 Jun 2020 14:57:42 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1592578663; bh=QD2dczz6KPktnBNPu/65B4VsW2BARSxk7kPZm1opUus=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=M0cYLASW/M88F+WRo5/BeUe6CZRBtwiGMyrCn6SdXZXOkKmEe9HI5sEOPsfY6rPrk kkqk2WLjXM1T67yP276qn6td4CTUqaHIuhPkOCjDfZ0X5RE/EOjpW9gKKNICFxPnUi 7P0RShFiIT5Qj3+drK8IcmDPy/SYuyTBJSCmV3mo= From: Greg Kroah-Hartman To: linux-kernel@vger.kernel.org Cc: Greg Kroah-Hartman , stable@vger.kernel.org, Douglas Anderson , Daniel Thompson , Sasha Levin Subject: [PATCH 4.19 108/267] kgdb: Disable WARN_CONSOLE_UNLOCKED for all kgdb Date: Fri, 19 Jun 2020 16:31:33 +0200 Message-Id: <20200619141654.039649405@linuxfoundation.org> X-Mailer: git-send-email 2.27.0 In-Reply-To: <20200619141648.840376470@linuxfoundation.org> References: <20200619141648.840376470@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 From: Douglas Anderson [ Upstream commit 202164fbfa2b2ffa3e66b504e0f126ba9a745006 ] In commit 81eaadcae81b ("kgdboc: disable the console lock when in kgdb") we avoided the WARN_CONSOLE_UNLOCKED() yell when we were in kgdboc. That still works fine, but it turns out that we get a similar yell when using other I/O drivers. One example is the "I/O driver" for the kgdb test suite (kgdbts). When I enabled that I again got the same yells. Even though "kgdbts" doesn't actually interact with the user over the console, using it still causes kgdb to print to the consoles. That trips the same warning: con_is_visible+0x60/0x68 con_scroll+0x110/0x1b8 lf+0x4c/0xc8 vt_console_print+0x1b8/0x348 vkdb_printf+0x320/0x89c kdb_printf+0x68/0x90 kdb_main_loop+0x190/0x860 kdb_stub+0x2cc/0x3ec kgdb_cpu_enter+0x268/0x744 kgdb_handle_exception+0x1a4/0x200 kgdb_compiled_brk_fn+0x34/0x44 brk_handler+0x7c/0xb8 do_debug_exception+0x1b4/0x228 Let's increment/decrement the "ignore_console_lock_warning" variable all the time when we enter the debugger. This will allow us to later revert commit 81eaadcae81b ("kgdboc: disable the console lock when in kgdb"). Signed-off-by: Douglas Anderson Reviewed-by: Greg Kroah-Hartman Reviewed-by: Daniel Thompson Link: https://lore.kernel.org/r/20200507130644.v4.1.Ied2b058357152ebcc8bf68edd6f20a11d98d7d4e@changeid Signed-off-by: Daniel Thompson Signed-off-by: Sasha Levin --- kernel/debug/debug_core.c | 4 ++++ 1 file changed, 4 insertions(+) diff --git a/kernel/debug/debug_core.c b/kernel/debug/debug_core.c index 94aa9ae0007a..d2799767aab8 100644 --- a/kernel/debug/debug_core.c +++ b/kernel/debug/debug_core.c @@ -577,6 +577,8 @@ return_normal: if (kgdb_skipexception(ks->ex_vector, ks->linux_regs)) goto kgdb_restore; + atomic_inc(&ignore_console_lock_warning); + /* Call the I/O driver's pre_exception routine */ if (dbg_io_ops->pre_exception) dbg_io_ops->pre_exception(); @@ -649,6 +651,8 @@ cpu_master_loop: if (dbg_io_ops->post_exception) dbg_io_ops->post_exception(); + atomic_dec(&ignore_console_lock_warning); + if (!kgdb_single_step) { raw_spin_unlock(&dbg_slave_lock); /* Wait till all the CPUs have quit from the debugger. */ -- 2.25.1