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=-10.1 required=3.0 tests=DKIMWL_WL_HIGH,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,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 42737C433DF for ; Tue, 9 Jun 2020 01:05:54 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 148EA20774 for ; Tue, 9 Jun 2020 01:05:54 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1591664754; bh=5Ku1WPXj1uoC+3mWt0Zai9p6vknK3/wtHVVZgtl6akY=; h=From:To:Cc:Subject:Date:In-Reply-To:References:List-ID:From; b=UhBNlKMWEI8oCNULiTRgtECQ45OEIyXhpIdC7QlP03zX4BC4ilVnoFDu1yaVs13Ro XmluwPFlbPanklt5ZcqlgH4zhZM7EAKwsBNtgQNBz2F9eovwDQeM1NnbQ+yRi240VZ ySYJq14/ia5weam7LGKv2w22Y+q9G5uY5WgNio4o= Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1728110AbgFIBFO (ORCPT ); Mon, 8 Jun 2020 21:05:14 -0400 Received: from mail.kernel.org ([198.145.29.99]:51154 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1727843AbgFHXHS (ORCPT ); Mon, 8 Jun 2020 19:07:18 -0400 Received: from sasha-vm.mshome.net (c-73-47-72-35.hsd1.nh.comcast.net [73.47.72.35]) (using TLSv1.2 with cipher ECDHE-RSA-AES128-GCM-SHA256 (128/128 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPSA id C833220897; Mon, 8 Jun 2020 23:07:17 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1591657638; bh=5Ku1WPXj1uoC+3mWt0Zai9p6vknK3/wtHVVZgtl6akY=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=ZjKqVt3QAuH6HFxBh1A1wLsSxcyA8sc9uFXuYuQyZwTn7jetmWcdmxdHcoXtzgilX ZDH7/hx/DOuNf9TYmUSzjsPtXmVcFXziTKy18wvKM2EOSItGcurviivcVB+nDIetRT dVuStyQ9OG7rqdfBdUeoJGez3Q/qDWnOcv2lBBGU= From: Sasha Levin To: linux-kernel@vger.kernel.org, stable@vger.kernel.org Cc: Douglas Anderson , Daniel Thompson , Sasha Levin , kgdb-bugreport@lists.sourceforge.net Subject: [PATCH AUTOSEL 5.7 056/274] kgdb: Prevent infinite recursive entries to the debugger Date: Mon, 8 Jun 2020 19:02:29 -0400 Message-Id: <20200608230607.3361041-56-sashal@kernel.org> X-Mailer: git-send-email 2.25.1 In-Reply-To: <20200608230607.3361041-1-sashal@kernel.org> References: <20200608230607.3361041-1-sashal@kernel.org> MIME-Version: 1.0 X-stable: review X-Patchwork-Hint: Ignore 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 3ca676e4ca60d1834bb77535dafe24169cadacef ] If we detect that we recursively entered the debugger we should hack our I/O ops to NULL so that the panic() in the next line won't actually cause another recursion into the debugger. The first line of kgdb_panic() will check this and return. Signed-off-by: Douglas Anderson Reviewed-by: Daniel Thompson Link: https://lore.kernel.org/r/20200507130644.v4.6.I89de39f68736c9de610e6f241e68d8dbc44bc266@changeid Signed-off-by: Daniel Thompson Signed-off-by: Sasha Levin --- kernel/debug/debug_core.c | 1 + 1 file changed, 1 insertion(+) diff --git a/kernel/debug/debug_core.c b/kernel/debug/debug_core.c index 950dc667c823..d47c7d6656cd 100644 --- a/kernel/debug/debug_core.c +++ b/kernel/debug/debug_core.c @@ -532,6 +532,7 @@ static int kgdb_reenter_check(struct kgdb_state *ks) if (exception_level > 1) { dump_stack(); + kgdb_io_module_registered = false; panic("Recursive entry to debugger"); } -- 2.25.1