From mboxrd@z Thu Jan 1 00:00:00 1970 From: Grant Likely Subject: Re: [PATCH v3 22/25] irq_domain/x86: Convert x86 (embedded) to use common irq_domain Date: Sat, 28 Jan 2012 17:35:50 -0700 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-Transfer-Encoding: 7bit Return-path: Content-Disposition: inline In-Reply-To: <20120128164405.GA20763-hfZtesqFncYOwBW4kG4KsQ@public.gmane.org> List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Errors-To: devicetree-discuss-bounces+gldd-devicetree-discuss=m.gmane.org-uLR06cmDAlY/bJ5BZ2RsiQ@public.gmane.org Sender: devicetree-discuss-bounces+gldd-devicetree-discuss=m.gmane.org-uLR06cmDAlY/bJ5BZ2RsiQ@public.gmane.org To: Sebastian Andrzej Siewior Cc: Stephen Rothwell , devicetree-discuss-uLR06cmDAlY/bJ5BZ2RsiQ@public.gmane.org, linux-kernel-u79uwXL29TY76Z2rM5mHXA@public.gmane.org, Rob Herring , Milton Miller , Thomas Gleixner , linuxppc-dev-uLR06cmDAlY/bJ5BZ2RsiQ@public.gmane.org, linux-arm-kernel-IAPFreCvJWM7uuMidbF8XUB+6BGkLq7r@public.gmane.org List-Id: devicetree@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.