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=-8.8 required=3.0 tests=BAYES_00,DKIMWL_WL_HIGH, DKIM_SIGNED,DKIM_VALID,HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_PATCH, MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS,URIBL_BLOCKED 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 EE99FC433DB for ; Mon, 22 Feb 2021 10:00:45 +0000 (UTC) Received: from merlin.infradead.org (merlin.infradead.org [205.233.59.134]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPS id 9CA2B614A5 for ; Mon, 22 Feb 2021 10:00:45 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 9CA2B614A5 Authentication-Results: mail.kernel.org; dmarc=fail (p=none dis=none) header.from=arm.com Authentication-Results: mail.kernel.org; spf=none smtp.mailfrom=linux-arm-kernel-bounces+linux-arm-kernel=archiver.kernel.org@lists.infradead.org DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=lists.infradead.org; s=merlin.20170209; h=Sender:Content-Transfer-Encoding: Content-Type:Cc:List-Subscribe:List-Help:List-Post:List-Archive: List-Unsubscribe:List-Id:In-Reply-To:MIME-Version:References:Message-ID: Subject:To:From:Date:Reply-To:Content-ID:Content-Description:Resent-Date: Resent-From:Resent-Sender:Resent-To:Resent-Cc:Resent-Message-ID:List-Owner; bh=RCauGH3L2vm3Lw3qbqq+PZQTq+gQSN+C6Rt9cnL7d98=; b=deqdM8w0nydBLi5Fv7hoTnPF3 161vuDNwaRpi9trFJ//sa2LxQ9STEmT3gBHK0plzFYwvYEmq0bBTVoyqUUu6E8omk01ElEhrzI1F2 PqfsrzA2HAjwTB08V47THzMGeZ+hYhKI6umMslLCEzbHuxBElHDQVExaYD4/us0VunjWzPFz+GTFg vxtx1FdFPps50oefSOpBaHvCwy+cF2wL613SuQL/RlUCELGck6P9JO0e3pDDZe9jcIyrLrb//+aIs S2uDfrXy3tjvdOlf2XDgx3DN/VmaLR1eW0aLU+yDbvQXRow+DTTlWe8IhcKWZ9J0YodaWqB61rb+H ihoCVWihA==; Received: from localhost ([::1] helo=merlin.infradead.org) by merlin.infradead.org with esmtp (Exim 4.92.3 #3 (Red Hat Linux)) id 1lE805-0003xD-Fe; Mon, 22 Feb 2021 09:59:33 +0000 Received: from foss.arm.com ([217.140.110.172]) by merlin.infradead.org with esmtp (Exim 4.92.3 #3 (Red Hat Linux)) id 1lE802-0003vx-Ef for linux-arm-kernel@lists.infradead.org; Mon, 22 Feb 2021 09:59:31 +0000 Received: from usa-sjc-imap-foss1.foss.arm.com (unknown [10.121.207.14]) by usa-sjc-mx-foss1.foss.arm.com (Postfix) with ESMTP id C65E4ED1; Mon, 22 Feb 2021 01:59:25 -0800 (PST) Received: from C02TD0UTHF1T.local (unknown [10.57.51.127]) by usa-sjc-imap-foss1.foss.arm.com (Postfix) with ESMTPSA id B2C873F73B; Mon, 22 Feb 2021 01:59:23 -0800 (PST) Date: Mon, 22 Feb 2021 09:59:13 +0000 From: Mark Rutland To: linux-arm-kernel@lists.infradead.org, linux-kernel@vger.kernel.org Subject: Re: [PATCH 5/8] arm64: irq: add a default handle_irq panic function Message-ID: <20210222095913.GA70951@C02TD0UTHF1T.local> References: <20210219113904.41736-1-mark.rutland@arm.com> <20210219113904.41736-6-mark.rutland@arm.com> MIME-Version: 1.0 Content-Disposition: inline In-Reply-To: <20210219113904.41736-6-mark.rutland@arm.com> X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.8.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20210222_045930_588558_CFC6BFA1 X-CRM114-Status: GOOD ( 17.06 ) X-BeenThere: linux-arm-kernel@lists.infradead.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Cc: catalin.marinas@arm.com, marcan@marcan.st, james.morse@arm.com, maz@kernel.org, tglx@linutronix.de, will@kernel.org Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Sender: "linux-arm-kernel" Errors-To: linux-arm-kernel-bounces+linux-arm-kernel=archiver.kernel.org@lists.infradead.org On Fri, Feb 19, 2021 at 11:39:01AM +0000, Mark Rutland wrote: > If we accidentally unmask IRQs before we've registered an IRQ > controller, handle_arch_irq will be NULL, and the IRQ exception handler > will branch to a bogus address. > > To make this easier to debug, this patch initialises handle_arch_irq to > a default handler which will panic(), making such problems easier to > debug. When we add support for FIQ handlers, we can follow the same > approach. > -void (*handle_arch_irq)(struct pt_regs *) __ro_after_init; > +void default_handle_irq(struct pt_regs *regs) > +{ > + panic("IRQ taken without a registered IRQ controller\n"); > +} The kbuild test robot pointed out that this should be static (likewise with default_handle_fiq in patch 8), since it's only used within this file, so I've updated that in my branch. Mark. > + > +void (*handle_arch_irq)(struct pt_regs *) __ro_after_init = default_handle_irq; > > int __init set_handle_irq(void (*handle_irq)(struct pt_regs *)) > { > - if (handle_arch_irq) > + if (handle_arch_irq != default_handle_irq) > return -EBUSY; > > handle_arch_irq = handle_irq; > @@ -87,7 +92,7 @@ void __init init_IRQ(void) > init_irq_stacks(); > init_irq_scs(); > irqchip_init(); > - if (!handle_arch_irq) > + if (handle_arch_irq == default_handle_irq) > panic("No interrupt controller found."); > > if (system_uses_irq_prio_masking()) { > -- > 2.11.0 > _______________________________________________ linux-arm-kernel mailing list linux-arm-kernel@lists.infradead.org http://lists.infradead.org/mailman/listinfo/linux-arm-kernel