Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1755100AbaA1Ogg (ORCPT ); Tue, 28 Jan 2014 09:36:36 -0500 Received: from mail-ea0-f169.google.com ([209.85.215.169]:32897 "EHLO mail-ea0-f169.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1754635AbaA1Ogf (ORCPT ); Tue, 28 Jan 2014 09:36:35 -0500 Message-ID: <52E7C06F.3010205@linaro.org> Date: Tue, 28 Jan 2014 14:36:31 +0000 From: Julien Grall User-Agent: Mozilla/5.0 (X11; Linux i686; rv:17.0) Gecko/20131104 Icedove/17.0.10 MIME-Version: 1.0 To: Stefano Stabellini CC: David Vrabel , linux-kernel@vger.kernel.org, konrad.wilk@oracle.com, boris.ostrovsky@oracle.com, xen-devel@lists.xenproject.org, ian.campbell@citrix.com, patches@linaro.org Subject: Re: [PATCH] xen/events: xen_evtchn_fifo_init can be called very late References: <1390869269-12502-1-git-send-email-julien.grall@linaro.org> <52E787FA.3080105@citrix.com> In-Reply-To: Content-Type: text/plain; charset=ISO-8859-1 Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On 01/28/2014 02:30 PM, Stefano Stabellini wrote: > On Tue, 28 Jan 2014, David Vrabel wrote: >> On 28/01/14 00:34, Julien Grall wrote: >>> On ARM, xen_init_IRQ (which calls xen_evtchn_fifo_init) is called after >>> all CPUs are online. It would mean that the notifier will never be called. >> >> Why does ARM call xen_init_IRQ() so late? Is it possible to call it >> earlier when only the boot CPU is online? There are problems with >> attempting to init FIFO event channels after all CPUs are online. >> >> If evtchn_fifo_init_control_block(cpu) fails on anything other than the >> first CPU, that CPU will be unable to receive any events. Xen will have >> been switched to FIFO mode and it is not possible to revert back to >> 2-level mode. > > We simply didn't need to be called that early. > Most of xen_guest_init could be moved to an early_initcall, if that is > necessary. > I'm actually working on a patch to move xen_init_IRQ() in early_initcall. -- Julien Grall -- 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/