Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S262820AbVEOMIG (ORCPT ); Sun, 15 May 2005 08:08:06 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S262819AbVEOMIG (ORCPT ); Sun, 15 May 2005 08:08:06 -0400 Received: from caramon.arm.linux.org.uk ([212.18.232.186]:54034 "EHLO caramon.arm.linux.org.uk") by vger.kernel.org with ESMTP id S262820AbVEOMHt (ORCPT ); Sun, 15 May 2005 08:07:49 -0400 Date: Sun, 15 May 2005 13:07:42 +0100 From: Russell King To: Andi Kleen Cc: Dave Jones , akpm@osdl.org, linux-kernel@vger.kernel.org Subject: Re: tickle nmi watchdog whilst doing serial writes. Message-ID: <20050515130742.A29619@flint.arm.linux.org.uk> Mail-Followup-To: Andi Kleen , Dave Jones , akpm@osdl.org, linux-kernel@vger.kernel.org References: <20050513184806.GA24166@redhat.com> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline User-Agent: Mutt/1.2.5.1i In-Reply-To: ; from ak@muc.de on Sun, May 15, 2005 at 01:38:02PM +0200 Sender: linux-kernel-owner@vger.kernel.org X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 1176 Lines: 30 On Sun, May 15, 2005 at 01:38:02PM +0200, Andi Kleen wrote: > Dave Jones writes: > > > > #include > > #include > > @@ -2099,8 +2100,10 @@ static inline void wait_for_xmitr(struct > > if (up->port.flags & UPF_CONS_FLOW) { > > tmout = 1000000; > > while (--tmout && > > - ((serial_in(up, UART_MSR) & UART_MSR_CTS) == 0)) > > + ((serial_in(up, UART_MSR) & UART_MSR_CTS) == 0)) { > > udelay(1); > > + touch_nmi_watchdog(); > > Note that touch_nmi_watchdog is not exported on i386 - Linus vetoed > that some time ago. The real fix of course is to use schedule_timeout(), > but that might break printk() with interrupts off :/ Not to mention printk() from atomic contexts and panic(). No, schedule_timeout() is _not_ a "real fix" but a kludge. -- Russell King Linux kernel 2.6 ARM Linux - http://www.arm.linux.org.uk/ maintainer of: 2.6 Serial core - 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/