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=-3.8 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 autolearn=no 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 C1DD2C433DF for ; Tue, 9 Jun 2020 04:31:48 +0000 (UTC) Received: from kanga.kvack.org (kanga.kvack.org [205.233.56.17]) by mail.kernel.org (Postfix) with ESMTP id 7958220810 for ; Tue, 9 Jun 2020 04:31:48 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (1024-bit key) header.d=kernel.org header.i=@kernel.org header.b="FcWbFgmS" DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 7958220810 Authentication-Results: mail.kernel.org; dmarc=none (p=none dis=none) header.from=linux-foundation.org Authentication-Results: mail.kernel.org; spf=pass smtp.mailfrom=owner-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix) id 218856B0095; Tue, 9 Jun 2020 00:31:48 -0400 (EDT) Received: by kanga.kvack.org (Postfix, from userid 40) id 1EF816B0098; Tue, 9 Jun 2020 00:31:48 -0400 (EDT) X-Delivered-To: int-list-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix, from userid 63042) id 1066A6B0099; Tue, 9 Jun 2020 00:31:48 -0400 (EDT) X-Delivered-To: linux-mm@kvack.org Received: from forelay.hostedemail.com (smtprelay0088.hostedemail.com [216.40.44.88]) by kanga.kvack.org (Postfix) with ESMTP id E8AFA6B0095 for ; Tue, 9 Jun 2020 00:31:47 -0400 (EDT) Received: from smtpin06.hostedemail.com (10.5.19.251.rfc1918.com [10.5.19.251]) by forelay01.hostedemail.com (Postfix) with ESMTP id B72F21804C532 for ; Tue, 9 Jun 2020 04:31:47 +0000 (UTC) X-FDA: 76908400254.06.root52_2310fe926dbf Received: from filter.hostedemail.com (10.5.16.251.rfc1918.com [10.5.16.251]) by smtpin06.hostedemail.com (Postfix) with ESMTP id 9125C10039241 for ; Tue, 9 Jun 2020 04:31:47 +0000 (UTC) X-HE-Tag: root52_2310fe926dbf X-Filterd-Recvd-Size: 4312 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by imf04.hostedemail.com (Postfix) with ESMTP for ; Tue, 9 Jun 2020 04:31:47 +0000 (UTC) Received: from localhost.localdomain (c-73-231-172-41.hsd1.ca.comcast.net [73.231.172.41]) (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 0C27920801; Tue, 9 Jun 2020 04:31:46 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1591677106; bh=OhXKBgI77oSHenNLXruiNsmSJ/BHqveVoN0zmm2NtYk=; h=Date:From:To:Subject:In-Reply-To:From; b=FcWbFgmSD/AUoQ3fvlCnYth8ggWKQSBjWg33TdJF6xYa2T2qt/+RVrerC3JWEOJRM +Thq3lZDiEFYINGw3JtCvrrKaaGkjJVRIGoLokwHNxRL28+k6NtDUkX4qWB5NkRB/n gep7fk/k3ddcw0TvK4np6ABfhTFA8RMAtwHj2hxY= Date: Mon, 08 Jun 2020 21:31:45 -0700 From: Andrew Morton To: akpm@linux-foundation.org, anton.ivanov@cambridgegreys.com, dima@arista.com, jdike@addtoit.com, linux-mm@kvack.org, mm-commits@vger.kernel.org, richard@nod.at, torvalds@linux-foundation.org Subject: [patch 36/93] um: add show_stack_loglvl() Message-ID: <20200609043145.T93ds4yjt%akpm@linux-foundation.org> In-Reply-To: <20200608212922.5b7fa74ca3f4e2444441b7f9@linux-foundation.org> User-Agent: s-nail v14.8.16 X-Rspamd-Queue-Id: 9125C10039241 X-Spamd-Result: default: False [0.00 / 100.00] X-Rspamd-Server: rspam05 X-Bogosity: Ham, tests=bogofilter, spamicity=0.000000, version=1.2.4 Sender: owner-linux-mm@kvack.org Precedence: bulk X-Loop: owner-majordomo@kvack.org List-ID: From: Dmitry Safonov Subject: um: add show_stack_loglvl() Currently, the log-level of show_stack() depends on a platform realization. It creates situations where the headers are printed with lower log level or higher than the stacktrace (depending on a platform or user). Furthermore, it forces the logic decision from user to an architecture side. In result, some users as sysrq/kdb/etc are doing tricks with temporary rising console_loglevel while printing their messages. And in result it not only may print unwanted messages from other CPUs, but also omit printing at all in the unlucky case where the printk() was deferred. Introducing log-level parameter and KERN_UNSUPPRESSED [1] seems an easier approach than introducing more printk buffers. Also, it will consolidate printings with headers. Introduce show_stack_loglvl(), that eventually will substitute show_stack(). [1]: https://lore.kernel.org/lkml/20190528002412.1625-1-dima@arista.com/T/#u Link: http://lkml.kernel.org/r/20200418201944.482088-37-dima@arista.com Signed-off-by: Dmitry Safonov Cc: Anton Ivanov Cc: Jeff Dike Cc: Richard Weinberger Signed-off-by: Andrew Morton --- arch/um/kernel/sysrq.c | 24 ++++++++++++++++-------- 1 file changed, 16 insertions(+), 8 deletions(-) --- a/arch/um/kernel/sysrq.c~um-add-show_stack_loglvl +++ a/arch/um/kernel/sysrq.c @@ -17,7 +17,9 @@ static void _print_addr(void *data, unsigned long address, int reliable) { - pr_info(" [<%08lx>] %s%pS\n", address, reliable ? "" : "? ", + const char *loglvl = data; + + printk("%s [<%08lx>] %s%pS\n", loglvl, address, reliable ? "" : "? ", (void *)address); } @@ -25,7 +27,8 @@ static const struct stacktrace_ops stack .address = _print_addr }; -void show_stack(struct task_struct *task, unsigned long *stack) +void show_stack_loglvl(struct task_struct *task, unsigned long *stack, + const char *loglvl) { struct pt_regs *segv_regs = current->thread.segv_regs; int i; @@ -39,17 +42,22 @@ void show_stack(struct task_struct *task if (!stack) stack = get_stack_pointer(task, segv_regs); - pr_info("Stack:\n"); + printk("%sStack:\n", loglvl); for (i = 0; i < 3 * STACKSLOTS_PER_LINE; i++) { if (kstack_end(stack)) break; if (i && ((i % STACKSLOTS_PER_LINE) == 0)) - pr_cont("\n"); + printk("%s\n", loglvl); pr_cont(" %08lx", *stack++); } - pr_cont("\n"); + printk("%s\n", loglvl); + + printk("%sCall Trace:\n", loglvl); + dump_trace(current, &stackops, (void *)loglvl); + printk("%s\n", loglvl); +} - pr_info("Call Trace:\n"); - dump_trace(current, &stackops, NULL); - pr_info("\n"); +void show_stack(struct task_struct *task, unsigned long *stack) +{ + show_stack_loglvl(task, stack, KERN_INFO); } _