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=-8.3 required=3.0 tests=DKIM_INVALID,DKIM_SIGNED, HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_PATCH,MAILING_LIST_MULTI,SIGNED_OFF_BY, SPF_PASS,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 7C290C43387 for ; Tue, 15 Jan 2019 15:55:01 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 3C4FA20645 for ; Tue, 15 Jan 2019 15:55:01 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=fail reason="signature verification failed" (2048-bit key) header.d=infradead.org header.i=@infradead.org header.b="VcrIzWeI" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1731258AbfAOPy7 (ORCPT ); Tue, 15 Jan 2019 10:54:59 -0500 Received: from bombadil.infradead.org ([198.137.202.133]:34556 "EHLO bombadil.infradead.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1731245AbfAOPy7 (ORCPT ); Tue, 15 Jan 2019 10:54:59 -0500 DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=infradead.org; s=bombadil.20170209; h=In-Reply-To:Content-Type:MIME-Version :References:Message-ID:Subject:Cc:To:From:Date:Sender:Reply-To: Content-Transfer-Encoding:Content-ID:Content-Description:Resent-Date: Resent-From:Resent-Sender:Resent-To:Resent-Cc:Resent-Message-ID:List-Id: List-Help:List-Unsubscribe:List-Subscribe:List-Post:List-Owner:List-Archive; bh=ZadGU3Ue9lBwLPdCvpqbXM4DriRaUkjOyxErV/tFVYw=; b=VcrIzWeIu8v+816nuswKchf7v Jp+5GVc+tOTIk4ijojXStG6Pbpm4pmqF915JFBfMVWO9WKHirygTxaqup0tFWdP7h9Cr6eOxWNEUw 1LnONXUShkJXzZZ2ea4m7BhQi3IgwKRFuqgXF5z/T9ZvtPCSINaIk6MDEDvX537e5ykuT18NVuoPa bmo0BBqCfWKo0u6GwdMlMEa3KRC+wRkju0cXTCL/y/kzh/QMLMJmFM3PnnEL4J1Xhteir4wj62QdP r3YzMIYcZXSl5b0Afk51Ltpc4DC5zqOdSbxRFt0VF/M6jyyep7MBMZLpg92xv9L/BgPe/MKYYGZG5 CxQDijRvA==; Received: from hch by bombadil.infradead.org with local (Exim 4.90_1 #2 (Red Hat Linux)) id 1gjR3G-0003bL-0G; Tue, 15 Jan 2019 15:54:54 +0000 Date: Tue, 15 Jan 2019 07:54:53 -0800 From: Christoph Hellwig To: Anup Patel Cc: Palmer Dabbelt , Albert Ou , Daniel Lezcano , Thomas Gleixner , Jason Cooper , Marc Zyngier , Christoph Hellwig , Atish Patra , linux-riscv@lists.infradead.org, linux-kernel@vger.kernel.org Subject: Re: [PATCH v4 3/5] irqchip: sifive-plic: Add warning in plic_init() if handler already present Message-ID: <20190115155453.GB13095@infradead.org> References: <20181227111821.80908-1-anup@brainfault.org> <20181227111821.80908-4-anup@brainfault.org> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20181227111821.80908-4-anup@brainfault.org> User-Agent: Mutt/1.9.2 (2017-12-15) X-SRS-Rewrite: SMTP reverse-path rewritten from by bombadil.infradead.org. See http://www.infradead.org/rpr.html Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Thu, Dec 27, 2018 at 04:48:19PM +0530, Anup Patel wrote: > We have two enteries (one for M-mode and another for S-mode) in the > interrupts-extended DT property of PLIC DT node for each HART. It is > expected that firmware/bootloader will set M-mode HWIRQ line of each > HART to 0xffffffff (i.e. -1) in interrupts-extended DT property > because Linux runs in S-mode only. > > If firmware/bootloader is buggy then it will not correctly update > interrupts-extended DT property which might result in a plic_handler > configured twice. This patch adds a warning in plic_init() if a > plic_handler is already marked present. This warning provides us > a hint about incorrectly updated interrupts-extended DT property. > > Signed-off-by: Anup Patel > Reviewed-by: Christoph Hellwig > --- > drivers/irqchip/irq-sifive-plic.c | 5 +++++ > 1 file changed, 5 insertions(+) > > diff --git a/drivers/irqchip/irq-sifive-plic.c b/drivers/irqchip/irq-sifive-plic.c > index 01bbbbffbcae..b9a0bcefe426 100644 > --- a/drivers/irqchip/irq-sifive-plic.c > +++ b/drivers/irqchip/irq-sifive-plic.c > @@ -229,6 +229,11 @@ static int __init plic_init(struct device_node *node, > > cpu = riscv_hartid_to_cpuid(hartid); > handler = per_cpu_ptr(&plic_handlers, cpu); > + if (handler->present) { > + pr_warn("handler already present for context %d.\n", i); > + continue; > + } > + Just use WARN_ON_ONCE?