From patchwork Tue Mar 10 12:41:03 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: 229664 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,URIBL_BLOCKED,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 035B3C10F27 for ; Tue, 10 Mar 2020 13:07:14 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id C285424693 for ; Tue, 10 Mar 2020 13:07:13 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1583845633; bh=lpS2d4UyXs4LMetf32AMMVWsLsmUh3rne8btWWb2Yjg=; h=From:To:Cc:Subject:Date:In-Reply-To:References:List-ID:From; b=XD45CyW7HUmyckRanx5r5qhiJTV+OvykLfz/WvEchVylryWeRzfkXcuMpHNpEAMRc Yf5pttjs1/VhX/bKKBTMh129Y1yBNZa+FhsJ/FkQxr9g3FcbRFVIIVHWLz44VJZCcH aPQwEjDW5uAYseU6vo0B/vP5csUCt7CzBjxfTTsU= Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1730928AbgCJNHN (ORCPT ); Tue, 10 Mar 2020 09:07:13 -0400 Received: from mail.kernel.org ([198.145.29.99]:52800 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1730918AbgCJNHJ (ORCPT ); Tue, 10 Mar 2020 09:07:09 -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 AB47C208E4; Tue, 10 Mar 2020 13:07:08 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1583845629; bh=lpS2d4UyXs4LMetf32AMMVWsLsmUh3rne8btWWb2Yjg=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=q16rQIXAWehqjpENCizvaSSFW0Paam/Ph30M1WTsRymfRfsP8d+9zVy+Q0qkwYtI0 swzWoKfYkKLxlCMSfYxSQUmeSTo/Mb3bL8tQv5Y/6BN/jYbIuhvmLWqzCZPWN64Qk/ n3pJdE+mJHJOvlVYsRMEFrIKekuCtusYx0pLhveE= From: Greg Kroah-Hartman To: linux-kernel@vger.kernel.org Cc: Greg Kroah-Hartman , stable@vger.kernel.org, "Steven Rostedt (VMware)" Subject: [PATCH 4.14 042/126] tracing: Disable trace_printk() on post poned tests Date: Tue, 10 Mar 2020 13:41:03 +0100 Message-Id: <20200310124207.018321580@linuxfoundation.org> X-Mailer: git-send-email 2.25.1 In-Reply-To: <20200310124203.704193207@linuxfoundation.org> References: <20200310124203.704193207@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: Steven Rostedt (VMware) commit 78041c0c9e935d9ce4086feeff6c569ed88ddfd4 upstream. The tracing seftests checks various aspects of the tracing infrastructure, and one is filtering. If trace_printk() is active during a self test, it can cause the filtering to fail, which will disable that part of the trace. To keep the selftests from failing because of trace_printk() calls, trace_printk() checks the variable tracing_selftest_running, and if set, it does not write to the tracing buffer. As some tracers were registered earlier in boot, the selftest they triggered would fail because not all the infrastructure was set up for the full selftest. Thus, some of the tests were post poned to when their infrastructure was ready (namely file system code). The postpone code did not set the tracing_seftest_running variable, and could fail if a trace_printk() was added and executed during their run. Cc: stable@vger.kernel.org Fixes: 9afecfbb95198 ("tracing: Postpone tracer start-up tests till the system is more robust") Signed-off-by: Steven Rostedt (VMware) Signed-off-by: Greg Kroah-Hartman --- kernel/trace/trace.c | 2 ++ 1 file changed, 2 insertions(+) --- a/kernel/trace/trace.c +++ b/kernel/trace/trace.c @@ -1543,6 +1543,7 @@ static __init int init_trace_selftests(v pr_info("Running postponed tracer tests:\n"); + tracing_selftest_running = true; list_for_each_entry_safe(p, n, &postponed_selftests, list) { ret = run_tracer_selftest(p->type); /* If the test fails, then warn and remove from available_tracers */ @@ -1561,6 +1562,7 @@ static __init int init_trace_selftests(v list_del(&p->list); kfree(p); } + tracing_selftest_running = false; out: mutex_unlock(&trace_types_lock);