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 Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id 2743BC433EF for ; Wed, 20 Apr 2022 14:06:14 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1379330AbiDTOI5 (ORCPT ); Wed, 20 Apr 2022 10:08:57 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:55116 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1379319AbiDTOIt (ORCPT ); Wed, 20 Apr 2022 10:08:49 -0400 Received: from mail-pj1-x1034.google.com (mail-pj1-x1034.google.com [IPv6:2607:f8b0:4864:20::1034]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 29F19433A9 for ; Wed, 20 Apr 2022 07:06:03 -0700 (PDT) Received: by mail-pj1-x1034.google.com with SMTP id s14-20020a17090a880e00b001caaf6d3dd1so5049077pjn.3 for ; Wed, 20 Apr 2022 07:06:03 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20210112; h=from:to:cc:subject:date:message-id:in-reply-to:references :mime-version:content-transfer-encoding; bh=2BbdN1kr5sGoIGX1dtNP33lYM00rauT2fciX5GfBZWk=; b=qPaGt8W1SqBUdOv9jbIxxS6ZyJAG8y3H45tHU2B/Rku9YW/MdoizmUnnz/k3hzJuFL PwKCyUmQuU00oINndtdwHZGGA9NeIIp4Ja7sCeCsbVIxJx/6vqgyB2Wm5sUvQsUWqYur 5XrzKb6MyXbu3tr/UpAj6JhAP06wKMWV63FSUCkG9AMYgMGPXfTHQ5PHuZqReyCIoQCa eqlk9W1RBcZV6naDaBUkwHO/hpuNEy2xvG02iPOa9acTWBJb1tned1CLlL2IYSmTyaej 2CPr3alR9H1u8xODMebyeOSV5SuwemSA5rHLqGmq1RboRqULztcVquB/DVby9RpXMCBU Vl+g== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20210112; h=x-gm-message-state:from:to:cc:subject:date:message-id:in-reply-to :references:mime-version:content-transfer-encoding; bh=2BbdN1kr5sGoIGX1dtNP33lYM00rauT2fciX5GfBZWk=; b=mGs3wqf1/TKQl5EC7hNRTj7GnsB8PfRrkko54boblKRZEZAYGkuFj3ia0Nf2dlr5N1 AUm+N4MAq2AGPaSBMt9xPpWD7eUWkKvdkCAfGML5v76PJzG0ktFCkvEzHeYTUAaENuhh I889ZZpi4V9d/E1K/pDY/Q0Ow9PtB9vFbPLnzAIkpuUzE1arPiSiS/tPfWocjKIsgHyU YTkKlemDnUyGya4WEU5rigFtT3DMO6g8kaCCSQkeKH5YlwLdunlvfw8VQULWCpa3cxGh LCf+jz0fT+2b1aw6sXJ8MRiu8O0sN8EASb4P56Neap9b6Mh3pbk4cV5cFgpvMOy2TQXq GHwg== X-Gm-Message-State: AOAM533pIHv3KxjOyLink1ii9JLEj0F8QOmfsAhnbo0xB0arJlRvZ7ot y1LEMA7IqNLxfDP33+sG9zlkjb3PfQ== X-Google-Smtp-Source: ABdhPJy93n7MJeCi0rQR1oa0d4fp/Wo2Zw8s/BAo8O+6HmRdt6k0l6D5iy/e9DK4uqrR9bVmfGDL/Q== X-Received: by 2002:a17:90b:350e:b0:1d2:b6e2:1000 with SMTP id ls14-20020a17090b350e00b001d2b6e21000mr4702893pjb.199.1650463562517; Wed, 20 Apr 2022 07:06:02 -0700 (PDT) Received: from piliu.users.ipa.redhat.com ([209.132.188.80]) by smtp.gmail.com with ESMTPSA id br10-20020a056a00440a00b0050a777cd10csm10959178pfb.91.2022.04.20.07.06.00 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Wed, 20 Apr 2022 07:06:02 -0700 (PDT) From: Pingfan Liu To: linux-kernel@vger.kernel.org Cc: Pingfan Liu , Thomas Gleixner , "Rafael J. Wysocki" Subject: [PATCH 6/9] pm/irq: make for_each_irq_desc() safe of irq_desc release Date: Wed, 20 Apr 2022 22:05:18 +0800 Message-Id: <20220420140521.45361-7-kernelfans@gmail.com> X-Mailer: git-send-email 2.31.1 In-Reply-To: <20220420140521.45361-1-kernelfans@gmail.com> References: <20220420140521.45361-1-kernelfans@gmail.com> MIME-Version: 1.0 Content-Transfer-Encoding: 8bit Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org The invloved context is no a RCU read section. Furthermore there may be more than one task at this point. Hence it demands a measure to prevent irq_desc from freeing. Use irq_lock_sparse to serve the protection purpose. Signed-off-by: Pingfan Liu Cc: Thomas Gleixner Cc: "Rafael J. Wysocki" To: linux-kernel@vger.kernel.org --- kernel/irq/pm.c | 3 +++ 1 file changed, 3 insertions(+) diff --git a/kernel/irq/pm.c b/kernel/irq/pm.c index ca71123a6130..4b67a4c7de3c 100644 --- a/kernel/irq/pm.c +++ b/kernel/irq/pm.c @@ -133,6 +133,7 @@ void suspend_device_irqs(void) struct irq_desc *desc; int irq; + irq_lock_sparse(); for_each_irq_desc(irq, desc) { unsigned long flags; bool sync; @@ -146,6 +147,7 @@ void suspend_device_irqs(void) if (sync) synchronize_irq(irq); } + irq_unlock_sparse(); } EXPORT_SYMBOL_GPL(suspend_device_irqs); @@ -186,6 +188,7 @@ static void resume_irqs(bool want_early) struct irq_desc *desc; int irq; + /* The early resume stage is free of irq_desc release */ for_each_irq_desc(irq, desc) { unsigned long flags; bool is_early = desc->action && -- 2.31.1