Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1757218Ab1FFNMW (ORCPT ); Mon, 6 Jun 2011 09:12:22 -0400 Received: from merlin.infradead.org ([205.233.59.134]:43655 "EHLO merlin.infradead.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1757124Ab1FFNMV convert rfc822-to-8bit (ORCPT ); Mon, 6 Jun 2011 09:12:21 -0400 Subject: Re: [debug patch] printk: Add a printk killswitch to robustify NMI watchdog messages From: Peter Zijlstra To: Ingo Molnar Cc: Arne Jansen , Linus Torvalds , mingo@redhat.com, hpa@zytor.com, linux-kernel@vger.kernel.org, efault@gmx.de, npiggin@kernel.dk, akpm@linux-foundation.org, frank.rowand@am.sony.com, tglx@linutronix.de, linux-tip-commits@vger.kernel.org In-Reply-To: <20110606131024.GA7386@elte.hu> References: <4DEB933C.1070900@die-jansens.de> <20110605151323.GA30590@elte.hu> <20110605152641.GA31124@elte.hu> <20110605153218.GA31471@elte.hu> <4DEBA9CC.4090503@die-jansens.de> <4DEBB05C.8090506@die-jansens.de> <4DEBB3DA.8060001@die-jansens.de> <20110605172052.GA1036@elte.hu> <4DEBBFF9.2030101@die-jansens.de> <20110605185957.GA3452@elte.hu> <20110606131024.GA7386@elte.hu> Content-Type: text/plain; charset="UTF-8" Content-Transfer-Encoding: 8BIT Date: Mon, 06 Jun 2011 15:12:08 +0200 Message-ID: <1307365928.2322.103.camel@twins> Mime-Version: 1.0 X-Mailer: Evolution 2.30.3 Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 1308 Lines: 42 On Mon, 2011-06-06 at 15:10 +0200, Ingo Molnar wrote: > diff --git a/kernel/printk.c b/kernel/printk.c > index 3518539..1b9d2be 100644 > --- a/kernel/printk.c > +++ b/kernel/printk.c > @@ -859,7 +859,6 @@ asmlinkage int vprintk(const char *fmt, va_list args) > zap_locks(); > } > > - lockdep_off(); At the very least you should also do: s/raw_local_irq_/local_irq/ on this function. > spin_lock(&logbuf_lock); > printk_cpu = this_cpu; > > @@ -947,7 +946,7 @@ asmlinkage int vprintk(const char *fmt, va_list args) > * Try to acquire and then immediately release the > * console semaphore. The release will do all the > * actual magic (print out buffers, wake up klogd, > - * etc). > + * etc). > * > * The console_trylock_for_printk() function > * will release 'logbuf_lock' regardless of whether it > @@ -956,7 +955,6 @@ asmlinkage int vprintk(const char *fmt, va_list args) > if (console_trylock_for_printk(this_cpu)) > console_unlock(); > > - lockdep_on(); > out_restore_irqs: > raw_local_irq_restore(flags); > -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/