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=-0.8 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, MAILING_LIST_MULTI,SPF_PASS 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 EC799C6778F for ; Fri, 27 Jul 2018 17:18:15 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 9DD0F208AF for ; Fri, 27 Jul 2018 17:18:15 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 9DD0F208AF Authentication-Results: mail.kernel.org; dmarc=none (p=none dis=none) header.from=perches.com Authentication-Results: mail.kernel.org; spf=none smtp.mailfrom=linux-kernel-owner@vger.kernel.org Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S2388836AbeG0SlD (ORCPT ); Fri, 27 Jul 2018 14:41:03 -0400 Received: from smtprelay0229.hostedemail.com ([216.40.44.229]:39774 "EHLO smtprelay.hostedemail.com" rhost-flags-OK-OK-OK-FAIL) by vger.kernel.org with ESMTP id S1728713AbeG0SlC (ORCPT ); Fri, 27 Jul 2018 14:41:02 -0400 Received: from filter.hostedemail.com (clb03-v110.bra.tucows.net [216.40.38.60]) by smtprelay06.hostedemail.com (Postfix) with ESMTP id 3BCAB18224D9C; Fri, 27 Jul 2018 17:18:12 +0000 (UTC) X-Session-Marker: 6A6F6540706572636865732E636F6D X-HE-Tag: waste09_8176f2ae0cf38 X-Filterd-Recvd-Size: 3682 Received: from XPS-9350 (unknown [47.151.153.53]) (Authenticated sender: joe@perches.com) by omf09.hostedemail.com (Postfix) with ESMTPA; Fri, 27 Jul 2018 17:18:09 +0000 (UTC) Message-ID: <26f07092cdde378ebb42c1034badde1b56521c36.camel@perches.com> Subject: Re: [PATCH v2 04/10] powerpc/traps: Use REG_FMT in show_signal_msg() From: Joe Perches To: LEROY Christophe , Murilo Opsfelder Araujo Cc: linuxppc-dev@lists.ozlabs.org, "Tobin C . Harding" , Sukadev Bhattiprolu , Simon Guo , Paul Mackerras , Nicholas Piggin , Michael Neuling , Michael Ellerman , "Eric W . Biederman" , Cyril Bur , Benjamin Herrenschmidt , Balbir Singh , Andrew Donnellan , Alastair D'Silva , linux-kernel@vger.kernel.org Date: Fri, 27 Jul 2018 10:18:08 -0700 In-Reply-To: <20180727184023.Horde.KRXPzZpG18uxt_B9sy_FBg5@messagerie.si.c-s.fr> References: <20180727145811.12334-1-muriloo@linux.ibm.com> <20180727145811.12334-5-muriloo@linux.ibm.com> <20180727184023.Horde.KRXPzZpG18uxt_B9sy_FBg5@messagerie.si.c-s.fr> Content-Type: text/plain; charset="ISO-8859-1" X-Mailer: Evolution 3.28.1-2 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 On Fri, 2018-07-27 at 18:40 +0200, LEROY Christophe wrote: > Murilo Opsfelder Araujo a écrit : > > > Simplify the message format by using REG_FMT as the register format. This > > avoids having two different formats and avoids checking for MSR_64BIT. > > Are you sure it is what we want ? > > Won't it change the behaviour for a 32 bits app running on a 64bits kernel ? [] > > diff --git a/arch/powerpc/kernel/traps.c b/arch/powerpc/kernel/traps.c [] > > @@ -311,17 +311,13 @@ static bool show_unhandled_signals_ratelimited(void) > > static void show_signal_msg(int signr, struct pt_regs *regs, int code, > > unsigned long addr) > > { > > - const char fmt32[] = KERN_INFO "%s[%d]: unhandled signal %d " \ > > - "at %08lx nip %08lx lr %08lx code %x\n"; > > - const char fmt64[] = KERN_INFO "%s[%d]: unhandled signal %d " \ > > - "at %016lx nip %016lx lr %016lx code %x\n"; > > - > > if (!unhandled_signal(current, signr)) > > return; > > > > - printk(regs->msr & MSR_64BIT ? fmt64 : fmt32, > > - current->comm, current->pid, signr, > > - addr, regs->nip, regs->link, code); > > + pr_info("%s[%d]: unhandled signal %d at "REG_FMT \ I think it better to use a space after the close " and also the line continuation is unnecessary. > > + " nip "REG_FMT" lr "REG_FMT" code %x\n", And spaces before the open quotes too. I'd also prefer the format on a single line: pr_info("%s[%d]: unhandled signal %d at " REG_FMT " nip " REG_FMT " lr " REG_FMT " code %x\n", > > + current->comm, current->pid, signr, addr, > > + regs->nip, regs->link, code); Seeing as these are all unsigned long, a better way to do this is to use %p and cast to pointer. This might be better anyway as this output exposes pointer addresses and instead would now use pointer hashed output. pr_info("%s[%d]: unhandled signal %d at %p nip %p lr %p code %x\n", current->comm, current->pid, signr, (void *)addr, (void *)regs->nip, (void *)regs->link, code); Use %px if you _really_ need to emit unhashed addresses. see: Documentation/core-api/printk-formats.rst