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 5BC4CC433EF for ; Wed, 20 Apr 2022 14:05:48 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1379282AbiDTOIc (ORCPT ); Wed, 20 Apr 2022 10:08:32 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:54778 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1379228AbiDTOI3 (ORCPT ); Wed, 20 Apr 2022 10:08:29 -0400 Received: from mail-pf1-x42a.google.com (mail-pf1-x42a.google.com [IPv6:2607:f8b0:4864:20::42a]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id D86E73E0DD for ; Wed, 20 Apr 2022 07:05:42 -0700 (PDT) Received: by mail-pf1-x42a.google.com with SMTP id z16so2031254pfh.3 for ; Wed, 20 Apr 2022 07:05:42 -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=XOKJyrS8QtzQoeHSOkLR7Y1klkfAcATQqfMHIhBU3dw=; b=ZX3TjlWVIUa6DvnJkhrX3gVqjsqt6eo7qvybPLa7T6oIsBDQw7Mb0r7DCJog0kL2Ol UH0MM6WRaZpuwbYQKyYfRLfEjhOsTDGfL4Bpga8Bv5xTUWvAWbWWcSd8XejK2Pd5cVf6 hGkgMpxNaZq5N7U69xre+mNALmWV1kex7FWpXVXvpPwDYweXGLrLQQaVXgM+1M8gER/z rUqaOucEHqdNVbx5YKuzMOL3zJ4XqLPkZ7/8kc+3mgeBpAOh0vo4LgmU1s51Al+K2kO7 hMHMYe0j+XJA0PIpN7aQJV+9W2BxmpwpyNQ/JNT9qTpbfaBjPcewH+6wHkwtTG/FmEEC BG/Q== 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=XOKJyrS8QtzQoeHSOkLR7Y1klkfAcATQqfMHIhBU3dw=; b=SJa5QR6+nhbqhfIhDJPckvn167oY2Fy/tFAAuCMJyoKBrxOlwglnMPY+jNPM0zzSRc i7bh3iHUE5pz3AqyY+PZ55i7EAiOBkg4y0E71cYX6/X5XBop8MUajvL+d+4sG1388nmI aBGt2KDwRcvrur6lXT3z+PLLfbEGDCx1x1FBXPOUKmDSYDbrPYjyuqEBnUvtzxI539Q5 APu0SPPHvlnH1fmjnvAZFEJtbKs/Snm5YMqcsgROnQMVY5sfihhOtcFzsonoY26Gkv11 HxGEIlXajfWY5qclqyvS8hNCPMpUfHw9YDJieTO0ngACZRkLnH26hQd6sNCMYAC2Qa7G HgIw== X-Gm-Message-State: AOAM531ik6cJh8hxL425JKhCy+qqvOiaetAonSlu6hgnL30gnzacu/gJ rwQJ49ZjIk6Kb/2s44X51Cy3z2rOiA== X-Google-Smtp-Source: ABdhPJwZ2FrncAHnqzoABz25ayfNH+RftLyH/2iLGiBMZpb5Jq/7i0nzYWrvg1eeYSh1pcTSPB0Erw== X-Received: by 2002:a63:ec46:0:b0:381:81c4:ebbd with SMTP id r6-20020a63ec46000000b0038181c4ebbdmr19418649pgj.534.1650463542277; Wed, 20 Apr 2022 07:05:42 -0700 (PDT) Received: from piliu.users.ipa.redhat.com ([209.132.188.80]) by smtp.gmail.com with ESMTPSA id br10-20020a056a00440a00b0050a777cd10csm10959178pfb.91.2022.04.20.07.05.40 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Wed, 20 Apr 2022 07:05:42 -0700 (PDT) From: Pingfan Liu To: linux-kernel@vger.kernel.org Cc: Pingfan Liu , Thomas Gleixner Subject: [PATCH 1/9] irq/irqdesc: put the lock at the exact place in irq_sysfs_init() Date: Wed, 20 Apr 2022 22:05:13 +0800 Message-Id: <20220420140521.45361-2-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 sparse_irq_lock is used to protect irq_desc, and furthermore irq_sysfs_init() is called only once, so put irq_lock_sparse() at the exact place, where the race condition may start. Signed-off-by: Pingfan Liu Cc: Thomas Gleixner To: linux-kernel@vger.kernel.org --- kernel/irq/irqdesc.c | 7 +++---- 1 file changed, 3 insertions(+), 4 deletions(-) diff --git a/kernel/irq/irqdesc.c b/kernel/irq/irqdesc.c index 939d21cd55c3..8d0982233277 100644 --- a/kernel/irq/irqdesc.c +++ b/kernel/irq/irqdesc.c @@ -312,15 +312,14 @@ static int __init irq_sysfs_init(void) struct irq_desc *desc; int irq; - /* Prevent concurrent irq alloc/free */ - irq_lock_sparse(); - irq_kobj_base = kobject_create_and_add("irq", kernel_kobj); if (!irq_kobj_base) { - irq_unlock_sparse(); return -ENOMEM; } + /* Prevent concurrent irq alloc/free */ + irq_lock_sparse(); + /* Add the already allocated interrupts */ for_each_irq_desc(irq, desc) irq_sysfs_add(irq, desc); -- 2.31.1