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=-13.1 required=3.0 tests=BAYES_00,DKIMWL_WL_HIGH, DKIM_SIGNED,DKIM_VALID,DKIM_VALID_AU,INCLUDES_PATCH,MAILING_LIST_MULTI, SIGNED_OFF_BY,SPF_HELO_NONE,SPF_PASS,USER_AGENT_GIT 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 CF8FBC433E7 for ; Mon, 12 Oct 2020 19:03:28 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 8A3BF21D6C for ; Mon, 12 Oct 2020 19:03:28 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1602529408; bh=GxyUJ336LKwVyiU9N8vXJbaW07K1JUB7kHNAeeWC/Ts=; h=From:To:Cc:Subject:Date:In-Reply-To:References:List-ID:From; b=lahb5aZHde2R0Qnau2W69mqGvTiBladd58Vn2xcSFGy3F8sxEh2tW5pCIPkA7niPo d95pPht8a8SP5hSBQXt3ZAGNIqW1S8n0UnSjzfy52FKP4TlmU31TKIxIFDgvZN4CWi WouvVYvke8DOgMuNddtsPcBsglVnuHS68XA7rXRo= Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S2390847AbgJLTD1 (ORCPT ); Mon, 12 Oct 2020 15:03:27 -0400 Received: from mail.kernel.org ([198.145.29.99]:52586 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S2390144AbgJLTDK (ORCPT ); Mon, 12 Oct 2020 15:03:10 -0400 Received: from sasha-vm.mshome.net (c-73-47-72-35.hsd1.nh.comcast.net [73.47.72.35]) (using TLSv1.2 with cipher ECDHE-RSA-AES128-GCM-SHA256 (128/128 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPSA id BE94421BE5; Mon, 12 Oct 2020 19:03:08 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1602529389; bh=GxyUJ336LKwVyiU9N8vXJbaW07K1JUB7kHNAeeWC/Ts=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=fkMuuLDwZ9RTuK4sRq/SVAfPIhq4Mthc6s5UQy4GtJ+CMnfrYzmcbQ+TrzwY/+ZYA tcaJrkSgbl56sR3QFuykZrlMa4RISaPB0f+p00XCM+O7VSYYAvob+ID3gOXITBLOop QSSTE3Ia48yAm6GWQZ9uaQdnM5JcPmSlUPuYewbA= From: Sasha Levin To: linux-kernel@vger.kernel.org, stable@vger.kernel.org Cc: Marc Zyngier , Linus Walleij , Sasha Levin , linux-gpio@vger.kernel.org Subject: [PATCH AUTOSEL 5.8 23/24] gpio: pca953x: Survive spurious interrupts Date: Mon, 12 Oct 2020 15:02:38 -0400 Message-Id: <20201012190239.3279198-23-sashal@kernel.org> X-Mailer: git-send-email 2.25.1 In-Reply-To: <20201012190239.3279198-1-sashal@kernel.org> References: <20201012190239.3279198-1-sashal@kernel.org> MIME-Version: 1.0 X-stable: review X-Patchwork-Hint: Ignore Content-Transfer-Encoding: 8bit Precedence: bulk List-ID: X-Mailing-List: linux-gpio@vger.kernel.org From: Marc Zyngier [ Upstream commit 8b81edd80baf12d64420daff1759380aa9a14998 ] The pca953x driver never checks the result of irq_find_mapping(), which returns 0 when no mapping is found. When a spurious interrupt is delivered (which can happen under obscure circumstances), the kernel explodes as it still tries to handle the error code as a real interrupt. Handle this particular case and warn on spurious interrupts. Signed-off-by: Marc Zyngier Link: https://lore.kernel.org/r/20201005140217.1390851-1-maz@kernel.org Signed-off-by: Linus Walleij Signed-off-by: Sasha Levin --- drivers/gpio/gpio-pca953x.c | 17 +++++++++++++++-- 1 file changed, 15 insertions(+), 2 deletions(-) diff --git a/drivers/gpio/gpio-pca953x.c b/drivers/gpio/gpio-pca953x.c index 11c3bbd105f11..1de182b85e4c4 100644 --- a/drivers/gpio/gpio-pca953x.c +++ b/drivers/gpio/gpio-pca953x.c @@ -821,8 +821,21 @@ static irqreturn_t pca953x_irq_handler(int irq, void *devid) ret = pca953x_irq_pending(chip, pending); mutex_unlock(&chip->i2c_lock); - for_each_set_bit(level, pending, gc->ngpio) - handle_nested_irq(irq_find_mapping(gc->irq.domain, level)); + if (ret) { + ret = 0; + + for_each_set_bit(level, pending, gc->ngpio) { + int nested_irq = irq_find_mapping(gc->irq.domain, level); + + if (unlikely(nested_irq <= 0)) { + dev_warn_ratelimited(gc->parent, "unmapped interrupt %d\n", level); + continue; + } + + handle_nested_irq(nested_irq); + ret = 1; + } + } return IRQ_RETVAL(ret); } -- 2.25.1