From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1751441AbdJCWKr (ORCPT ); Tue, 3 Oct 2017 18:10:47 -0400 Received: from mail.kernel.org ([198.145.29.99]:45954 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1750841AbdJCWKo (ORCPT ); Tue, 3 Oct 2017 18:10:44 -0400 DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org EDF06218CA Authentication-Results: mail.kernel.org; dmarc=none (p=none dis=none) header.from=goodmis.org Authentication-Results: mail.kernel.org; spf=none smtp.mailfrom=rostedt@goodmis.org Date: Tue, 3 Oct 2017 18:10:41 -0400 From: Steven Rostedt To: Peter Zijlstra Cc: pmladek@suse.com, sergey.senozhatsky@gmail.com, linux-kernel@vger.kernel.org, mingo@kernel.org, tglx@linutronix.de, Jason Wessel Subject: Re: [PATCH 1/3] printk: Fix kdb_trap_printk placement Message-ID: <20171003181041.6b64e905@gandalf.local.home> In-Reply-To: <20170928122513.328354788@infradead.org> References: <20170928121823.430053219@infradead.org> <20170928122513.328354788@infradead.org> X-Mailer: Claws Mail 3.14.0 (GTK+ 2.24.31; x86_64-pc-linux-gnu) MIME-Version: 1.0 Content-Type: text/plain; charset=US-ASCII Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Thu, 28 Sep 2017 14:18:24 +0200 Peter Zijlstra wrote: > Some people figured vprintk_emit() makes for a nice API and exported > it, bypassing the kdb trap. > > This still leaves vprintk_nmi() outside of the kbd reach, should that > be fixed too? I believe the vprintk_nmi() just buffers the prints, and doesn't send it out. I'm guessing not then. > > Cc: Jason Wessel > Signed-off-by: Peter Zijlstra (Intel) > --- > kernel/printk/printk.c | 18 ++++++------------ > 1 file changed, 6 insertions(+), 12 deletions(-) > > --- a/kernel/printk/printk.c > +++ b/kernel/printk/printk.c > @@ -1811,6 +1811,11 @@ asmlinkage int vprintk_emit(int facility > int printed_len; > bool in_sched = false; > > +#ifdef CONFIG_KGDB_KDB > + if (unlikely(kdb_trap_printk && kdb_printf_cpu < 0)) > + return vkdb_printf(KDB_MSGSRC_PRINTK, fmt, args); > +#endif > + > if (level == LOGLEVEL_SCHED) { > level = LOGLEVEL_DEFAULT; > in_sched = true; > @@ -1903,18 +1908,7 @@ EXPORT_SYMBOL(printk_emit); > > int vprintk_default(const char *fmt, va_list args) > { > - int r; > - > -#ifdef CONFIG_KGDB_KDB > - /* Allow to pass printk() to kdb but avoid a recursion. */ > - if (unlikely(kdb_trap_printk && kdb_printf_cpu < 0)) { > - r = vkdb_printf(KDB_MSGSRC_PRINTK, fmt, args); > - return r; > - } > -#endif > - r = vprintk_emit(0, LOGLEVEL_DEFAULT, NULL, 0, fmt, args); > - > - return r; Hmm, what was with the return r before?? Anyway, Reviewed-by: Steven Rostedt (VMware) > + return vprintk_emit(0, LOGLEVEL_DEFAULT, NULL, 0, fmt, args); > } > EXPORT_SYMBOL_GPL(vprintk_default); > >