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 C1948C433E0 for ; Fri, 19 Jun 2020 16:11:10 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 9C0812168B for ; Fri, 19 Jun 2020 16:11:10 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1592583070; bh=BswtJRKHutJLb0chTOqQLF44TaQNCFggqTRlWcKon54=; h=From:To:Cc:Subject:Date:In-Reply-To:References:List-ID:From; b=2CbZzSrtXwpnV5cbMq1p7qwJUw1FASXZZ/2ESDsvqrQ38J5JmtpD/8rQDukP4hhkD nCr1LoiPf1BLspUYvDVDWYPRXcZY2BQBATQ2iJFzfZ4n8Nz5kn2NWF9RhVJvbogyci izaIIdaYEQ3KXkfr+1Ag11P3VLdTn0AFNp7DyfKs= Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S2392063AbgFSQLB (ORCPT ); Fri, 19 Jun 2020 12:11:01 -0400 Received: from mail.kernel.org ([198.145.29.99]:35294 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S2391409AbgFSPGP (ORCPT ); Fri, 19 Jun 2020 11:06:15 -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 90A5521974; Fri, 19 Jun 2020 15:06:14 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1592579175; bh=BswtJRKHutJLb0chTOqQLF44TaQNCFggqTRlWcKon54=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=vX2I66Xp7hqcfGnCGSEO1/Otbnn5QnYNJlB02TBxvLpRKXFzpLrSD/m8dXt217g2g buJPzRfR6/xpgGIAre7d6xsxFUU9GvxElAkKoyu0Zq6qrXgvDHA45QcSgDHk0ukp9g S1KaihWrzs9xPM4juBEbUMjRElBfwAjQ4Qz38Z2M= 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 5.4 036/261] kgdb: Disable WARN_CONSOLE_UNLOCKED for all kgdb Date: Fri, 19 Jun 2020 16:30:47 +0200 Message-Id: <20200619141651.643978819@linuxfoundation.org> X-Mailer: git-send-email 2.27.0 In-Reply-To: <20200619141649.878808811@linuxfoundation.org> References: <20200619141649.878808811@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 f76d6f77dd5e..d0d557c0ceff 100644 --- a/kernel/debug/debug_core.c +++ b/kernel/debug/debug_core.c @@ -634,6 +634,8 @@ 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(); @@ -706,6 +708,8 @@ 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