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=-8.8 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, INCLUDES_PATCH,MAILING_LIST_MULTI,SIGNED_OFF_BY,SPF_HELO_NONE,SPF_PASS, USER_AGENT_GIT autolearn=ham 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 6E177C4321A for ; Tue, 11 Jun 2019 14:13:31 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 4C6D6205ED for ; Tue, 11 Jun 2019 14:13:31 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S2389804AbfFKONa (ORCPT ); Tue, 11 Jun 2019 10:13:30 -0400 Received: from mx2.suse.de ([195.135.220.15]:44176 "EHLO mx1.suse.de" rhost-flags-OK-OK-OK-FAIL) by vger.kernel.org with ESMTP id S2388728AbfFKON1 (ORCPT ); Tue, 11 Jun 2019 10:13:27 -0400 X-Virus-Scanned: by amavisd-new at test-mx.suse.de Received: from relay2.suse.de (unknown [195.135.220.254]) by mx1.suse.de (Postfix) with ESMTP id 32FF0AF8C; Tue, 11 Jun 2019 14:13:26 +0000 (UTC) From: Miroslav Benes To: jpoimboe@redhat.com, jikos@kernel.org, pmladek@suse.com Cc: joe.lawrence@redhat.com, kamalesh@linux.vnet.ibm.com, live-patching@vger.kernel.org, linux-kernel@vger.kernel.org, Miroslav Benes Subject: [PATCH v4 3/3] livepatch: Remove duplicate warning about missing reliable stacktrace support Date: Tue, 11 Jun 2019 16:13:20 +0200 Message-Id: <20190611141320.25359-4-mbenes@suse.cz> X-Mailer: git-send-email 2.21.0 In-Reply-To: <20190611141320.25359-1-mbenes@suse.cz> References: <20190611141320.25359-1-mbenes@suse.cz> MIME-Version: 1.0 Content-Transfer-Encoding: 8bit Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org From: Petr Mladek WARN_ON_ONCE() could not be called safely under rq lock because of console deadlock issues. Moreover WARN_ON_ONCE() is superfluous in klp_check_stack(), because stack_trace_save_tsk_reliable() cannot return -ENOSYS thanks to klp_have_reliable_stack() check in klp_try_switch_task(). Signed-off-by: Petr Mladek [ mbenes: changelog edited ] Signed-off-by: Miroslav Benes --- kernel/livepatch/transition.c | 1 - 1 file changed, 1 deletion(-) diff --git a/kernel/livepatch/transition.c b/kernel/livepatch/transition.c index 7e7ef04689d1..cdf318d86dd6 100644 --- a/kernel/livepatch/transition.c +++ b/kernel/livepatch/transition.c @@ -247,7 +247,6 @@ static int klp_check_stack(struct task_struct *task, char *err_buf) int ret, nr_entries; ret = stack_trace_save_tsk_reliable(task, entries, ARRAY_SIZE(entries)); - WARN_ON_ONCE(ret == -ENOSYS); if (ret < 0) { snprintf(err_buf, STACK_ERR_BUF_SIZE, "%s: %s:%d has an unreliable stack\n", -- 2.21.0