From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1752621Ab2A2Afx (ORCPT ); Sat, 28 Jan 2012 19:35:53 -0500 Received: from mail-pw0-f46.google.com ([209.85.160.46]:60062 "EHLO mail-pw0-f46.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751980Ab2A2Afw (ORCPT ); Sat, 28 Jan 2012 19:35:52 -0500 Date: Sat, 28 Jan 2012 17:35:50 -0700 From: Grant Likely To: Sebastian Andrzej Siewior Cc: linux-kernel@vger.kernel.org, Benjamin Herrenschmidt , Thomas Gleixner , Milton Miller , Rob Herring , Stephen Rothwell , devicetree-discuss@lists.ozlabs.org, linux-arm-kernel@lists.infradead.org, linuxppc-dev@lists.ozlabs.org Subject: Re: [PATCH v3 22/25] irq_domain/x86: Convert x86 (embedded) to use common irq_domain Message-ID: <20120129003550.GA21385@ponder.secretlab.ca> References: <1327700179-17454-1-git-send-email-grant.likely@secretlab.ca> <1327700179-17454-23-git-send-email-grant.likely@secretlab.ca> <20120128164405.GA20763@linutronix.de> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20120128164405.GA20763@linutronix.de> User-Agent: Mutt/1.5.21 (2010-09-15) Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Sat, Jan 28, 2012 at 05:44:05PM +0100, Sebastian Andrzej Siewior wrote: > * Grant Likely | 2012-01-27 14:36:16 [-0700]: > > >This patch removes the x86-specific definition of irq_domain and replaces > >it with the common implementation. > > I pulled your devicetree/next tree. After this patch I get: > > |Hierarchical RCU implementation. > |NR_IRQS:2304 nr_irqs:256 16 > |------------[ cut here ]------------ > |WARNING: at /home/bigeasy/work/shiva/git/linux-2.6-tip/kernel/irq/irqdomain.c:114 irq_domain_add_legacy+0x75/0x150() > |Modules linked in: > |Pid: 0, comm: swapper/0 Not tainted 3.3.0-rc1+ #65 > |Call Trace: > | [] ? printk+0x18/0x1a > | [] warn_slowpath_common+0x6d/0xa0 > | [] ? irq_domain_add_legacy+0x75/0x150 > | [] ? irq_domain_add_legacy+0x75/0x150 > | [] warn_slowpath_null+0x1d/0x20 > | [] irq_domain_add_legacy+0x75/0x150 > | [] x86_add_irq_domains+0x96/0xd6 > | [] init_IRQ+0x8/0x33 > | [] start_kernel+0x191/0x2e1 > | [] ? loglevel+0x2b/0x2b > | [] i386_start_kernel+0x81/0x86 > |---[ end trace 4eaa2a86a8e2da22 ]--- > |------------[ cut here ]------------ > |kernel BUG at /home/bigeasy/work/shiva/git/linux-2.6-tip/arch/x86/kernel/devicetree.c:367! > > The warning is comming from this piece in irq_domain_add_legacy() > |for (i = 0; i < size; i++) { > | int irq = first_irq + i; > | struct irq_data *irq_data = irq_get_irq_data(irq); > | > | if (WARN_ON(!irq_data || irq_data->domain)) { > > irq_data is NULL here. > > | mutex_unlock(&irq_domain_mutex); > | of_node_put(domain->of_node); > | kfree(domain); > | return NULL; > | } > | } > | > > This is not always the case. arch_early_irq_init() in [0] sets up the > first 16 entries. The reminaing few (there is a toal of 24 irqs for > first ioapic and a second ioapic) are not initialized. This happens > later via ->xlate, ioapic_xlate() => io_apic_setup_irq_pin() => > alloc_irq_and_cfg_at() calls irq_set_chip_data() on demand. > > [0] arch/x86/kernel/apic/io_apic.c That's not going to work then. The irqs must not be set up in ->xlate. They need to be set up either before creating the irq_domain, or in the .map hook. Inside the map hook is preferred, but having some configured and some not at initialization time does make it difficult g.