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=-10.0 required=3.0 tests=DKIMWL_WL_HIGH,DKIM_SIGNED, DKIM_VALID,HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_PATCH,MAILING_LIST_MULTI, SIGNED_OFF_BY,SPF_PASS,URIBL_BLOCKED,USER_AGENT_MUTT 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 EB4A8C43441 for ; Tue, 27 Nov 2018 10:11:40 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id B3C5F208E7 for ; Tue, 27 Nov 2018 10:11:40 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (1024-bit key) header.d=kernel.org header.i=@kernel.org header.b="W9mOuB7B" DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org B3C5F208E7 Authentication-Results: mail.kernel.org; dmarc=none (p=none dis=none) header.from=linuxfoundation.org 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 S1730472AbeK0VJC (ORCPT ); Tue, 27 Nov 2018 16:09:02 -0500 Received: from mail.kernel.org ([198.145.29.99]:57518 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1730295AbeK0VJC (ORCPT ); Tue, 27 Nov 2018 16:09:02 -0500 Received: from localhost (5356596B.cm-6-7b.dynamic.ziggo.nl [83.86.89.107]) (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 2CEA92086B; Tue, 27 Nov 2018 10:11:38 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1543313498; bh=JNdGem/T1QP+a7tc9O9rXdoxyYdSyHTwkHvh2tp3FNI=; h=Date:From:To:Cc:Subject:References:In-Reply-To:From; b=W9mOuB7BocF2/gthMGEcFGdJimAwMmdS2purhkp7yu6c+lEmpVHKPmnj2yvzX70aX o5HTa4wcWUlAdRtZftZ/+/dnO7bgtJeEDBna7OiI2Ou3q/2wmIwf0TxsBYJoNqHdfM YnSeg8tj6cq/migdAtn+I8/mIrogiV8RdY3SNrFo= Date: Tue, 27 Nov 2018 11:11:35 +0100 From: Greg KH To: Mark Tomlinson Cc: linux-kernel@vger.kernel.org Subject: Re: [PATCH RESEND] tty/sysrq: Do not call sync directly from sysrq_do_reset() Message-ID: <20181127101135.GA15856@kroah.com> References: <20181126205723.14478-1-mark.tomlinson@alliedtelesis.co.nz> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20181126205723.14478-1-mark.tomlinson@alliedtelesis.co.nz> User-Agent: Mutt/1.11.0 (2018-11-25) Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Tue, Nov 27, 2018 at 09:57:23AM +1300, Mark Tomlinson wrote: > sysrq_do_reset() is called in softirq context, so it cannot call > sync() directly. Instead, call orderly_reboot(), which creates a work > item to run /sbin/reboot, or do emergency_sync and restart if the > command fails. > > Signed-off-by: Mark Tomlinson > --- > drivers/tty/sysrq.c | 3 +-- > 1 file changed, 1 insertion(+), 2 deletions(-) > > diff --git a/drivers/tty/sysrq.c b/drivers/tty/sysrq.c > index ad1ee5d01b53..f2ca32c1ad7c 100644 > --- a/drivers/tty/sysrq.c > +++ b/drivers/tty/sysrq.c > @@ -660,8 +660,7 @@ static void sysrq_do_reset(struct timer_list *t) > > state->reset_requested = true; > > - ksys_sync(); > - kernel_restart(NULL); > + orderly_reboot(); Is this something new? Why haven't we had reports of this failing in the past? Or has something changed recently to cause this to now be needed? thanks, greg k-h