Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id 25F01C4332F for ; Wed, 24 Nov 2021 12:43:06 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S244056AbhKXMqM (ORCPT ); Wed, 24 Nov 2021 07:46:12 -0500 Received: from mail.kernel.org ([198.145.29.99]:41826 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1345211AbhKXMlG (ORCPT ); Wed, 24 Nov 2021 07:41:06 -0500 Received: by mail.kernel.org (Postfix) with ESMTPSA id 64DDE61216; Wed, 24 Nov 2021 12:24:40 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=linuxfoundation.org; s=korg; t=1637756680; bh=xqVALZlNQfC1BHtDBPx9Qlj03SZPArGR0HpXbatcAuw=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=nNPiRKUTPV0WBeg/R/nL3yE/spIuW04ssySUGqmcW6GE5OeQWicAY/Xie27sl1YFl 9oXJif7Hi90g5ATpeXjvXcF2oboQzZ3Woi4IVvSO/3JiwOmzE7H+sOd8jeJMc9T47v sx1KZ1pqXl8/9gce4JlsIJgbkc7bZyZdNYFDnqoc= From: Greg Kroah-Hartman To: linux-kernel@vger.kernel.org Cc: Greg Kroah-Hartman , stable@vger.kernel.org, Jackie Liu , Krzysztof Kozlowski , Sasha Levin Subject: [PATCH 4.14 140/251] ARM: s3c: irq-s3c24xx: Fix return value check for s3c24xx_init_intc() Date: Wed, 24 Nov 2021 12:56:22 +0100 Message-Id: <20211124115715.127598283@linuxfoundation.org> X-Mailer: git-send-email 2.34.0 In-Reply-To: <20211124115710.214900256@linuxfoundation.org> References: <20211124115710.214900256@linuxfoundation.org> User-Agent: quilt/0.66 MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org From: Jackie Liu [ Upstream commit 2aa717473ce96c93ae43a5dc8c23cedc8ce7dd9f ] The s3c24xx_init_intc() returns an error pointer upon failure, not NULL. let's add an error pointer check in s3c24xx_handle_irq. s3c_intc[0] is not NULL or ERR, we can simplify the code. Fixes: 1f629b7a3ced ("ARM: S3C24XX: transform irq handling into a declarative form") Signed-off-by: Jackie Liu Link: https://lore.kernel.org/r/20210901123557.1043953-1-liu.yun@linux.dev Signed-off-by: Krzysztof Kozlowski Signed-off-by: Sasha Levin --- drivers/irqchip/irq-s3c24xx.c | 22 ++++++++++++++++++---- 1 file changed, 18 insertions(+), 4 deletions(-) diff --git a/drivers/irqchip/irq-s3c24xx.c b/drivers/irqchip/irq-s3c24xx.c index c25ce5af091ad..e92ab62cc87d9 100644 --- a/drivers/irqchip/irq-s3c24xx.c +++ b/drivers/irqchip/irq-s3c24xx.c @@ -368,11 +368,25 @@ static inline int s3c24xx_handle_intc(struct s3c_irq_intc *intc, asmlinkage void __exception_irq_entry s3c24xx_handle_irq(struct pt_regs *regs) { do { - if (likely(s3c_intc[0])) - if (s3c24xx_handle_intc(s3c_intc[0], regs, 0)) - continue; + /* + * For platform based machines, neither ERR nor NULL can happen here. + * The s3c24xx_handle_irq() will be set as IRQ handler iff this succeeds: + * + * s3c_intc[0] = s3c24xx_init_intc() + * + * If this fails, the next calls to s3c24xx_init_intc() won't be executed. + * + * For DT machine, s3c_init_intc_of() could set the IRQ handler without + * setting s3c_intc[0] only if it was called with num_ctrl=0. There is no + * such code path, so again the s3c_intc[0] will have a valid pointer if + * set_handle_irq() is called. + * + * Therefore in s3c24xx_handle_irq(), the s3c_intc[0] is always something. + */ + if (s3c24xx_handle_intc(s3c_intc[0], regs, 0)) + continue; - if (s3c_intc[2]) + if (!IS_ERR_OR_NULL(s3c_intc[2])) if (s3c24xx_handle_intc(s3c_intc[2], regs, 64)) continue; -- 2.33.0