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=-9.1 required=3.0 tests=DKIMWL_WL_MED,DKIM_SIGNED, DKIM_VALID,HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_PATCH,MAILING_LIST_MULTI, SIGNED_OFF_BY,SPF_PASS,URIBL_BLOCKED,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 B724EECDE47 for ; Thu, 8 Nov 2018 16:47:55 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 7B8B4206BA for ; Thu, 8 Nov 2018 16:47:55 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (2048-bit key) header.d=bgdev-pl.20150623.gappssmtp.com header.i=@bgdev-pl.20150623.gappssmtp.com header.b="LkBD1Mmr" DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 7B8B4206BA Authentication-Results: mail.kernel.org; dmarc=none (p=none dis=none) header.from=bgdev.pl Authentication-Results: mail.kernel.org; spf=none smtp.mailfrom=linux-kernel-owner@vger.kernel.org Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1727037AbeKICYN (ORCPT ); Thu, 8 Nov 2018 21:24:13 -0500 Received: from mail-wr1-f65.google.com ([209.85.221.65]:43620 "EHLO mail-wr1-f65.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726421AbeKICYM (ORCPT ); Thu, 8 Nov 2018 21:24:12 -0500 Received: by mail-wr1-f65.google.com with SMTP id y3-v6so21681819wrh.10 for ; Thu, 08 Nov 2018 08:47:52 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=bgdev-pl.20150623.gappssmtp.com; s=20150623; h=from:to:cc:subject:date:message-id:mime-version :content-transfer-encoding; bh=Wi3RtwoU7gFjKqwR0o2e4Ytwq9fzaxAaDuVQ7ukHVnA=; b=LkBD1MmrAnQ18ZGE33LMrYtO9FAKIcBFgeFfsKePaGfnlFWOkP12lsoOraoRrwCH+8 tAt/zibmuRv+MYGrTZPKMRDIDx3g9tsqNMFXyAGcIlSLzynNbRicdybcfruMaeTMTagh 9vDLlEpZkoN0MmlodsQ4pPmtulZ3FuiMCGuPNDDDgAIhVgbWb6D7H2di64WcucNsSHTR LU2iEwzdwdlVb0Ox8L4J7mMUinX7aZ4QJP1Lxt9qTCghd4k5EG3EOR2R0likn/cgiPbo j9heTuDFAm9sQL77zPt8QJ60Ed4cAL9WqdL5irtqy/cSuWIvNQtkN63QEYAKiivQklHY aaIA== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:from:to:cc:subject:date:message-id:mime-version :content-transfer-encoding; bh=Wi3RtwoU7gFjKqwR0o2e4Ytwq9fzaxAaDuVQ7ukHVnA=; b=PgpwGKi+OXcIdBlj/Bk1h9mXi1JQnbib4tRxw9eF0bBHSaCTCswbX4CD5rLvhixFp8 vzpjLh7KoF/XFiRUveKlb5uMQJL+2W+Y7ROmY/gZ1N+7EoAq9vR6+0s8KcCdwx81x1GQ 9/JDhSD2okrSjwP1j7EPjKd8eBE3+AZDmnVZLj9+JxODMRb1Fw8pFgEr0ufxJORNyVnd 5gQpjLdbn060bSc0587uWPhnFkAMTTYSae4x1HhnvFrDVbZ/LZr6ILQJH+ONAtYzUPKL AQFeDYo0aD7z6y/tfvHFVNi2+bGT83v7eHQqNNseir0CGSvdOwv4kwwsc+FHi7J5BT/7 qUUA== X-Gm-Message-State: AGRZ1gLCJCqbxf8ElojwrxQ1rG+8t0gBc0Zy3ljATiG55AT9xX3qniR3 Zsl0N2YvNXtwfbzOT+/tQPjBKvNV/LY= X-Google-Smtp-Source: AJdET5cT0aS20yaRcn68Fu4pRE7/SRhCWL1nI4bJYbfVpf4Qccfd4XY0C3kMscgWaBgRp7pIrRrbng== X-Received: by 2002:a5d:4406:: with SMTP id z6-v6mr4918103wrq.294.1541695671774; Thu, 08 Nov 2018 08:47:51 -0800 (PST) Received: from debian-brgl.lan ([2a01:cb1d:af:5b00:6d6c:8493:1ab5:dad7]) by smtp.gmail.com with ESMTPSA id i7-v6sm2810606wrb.3.2018.11.08.08.47.50 (version=TLS1_2 cipher=ECDHE-RSA-AES128-GCM-SHA256 bits=128/128); Thu, 08 Nov 2018 08:47:51 -0800 (PST) From: Bartosz Golaszewski To: Thomas Gleixner , =?UTF-8?q?Uwe=20Kleine-K=C3=B6nig?= Cc: linux-kernel@vger.kernel.org, Bartosz Golaszewski Subject: [PATCH] irq/irq_sim: add locking Date: Thu, 8 Nov 2018 17:47:48 +0100 Message-Id: <20181108164748.31222-1-brgl@bgdev.pl> X-Mailer: git-send-email 2.19.1 MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Two threads can try to fire the irq_sim with different offsets and will end up fighting for the irq_work asignment. To fix it: add a mutex and lock it before firing. Suggested-by: Uwe Kleine-König Signed-off-by: Bartosz Golaszewski --- include/linux/irq_sim.h | 1 + kernel/irq/irq_sim.c | 5 +++++ 2 files changed, 6 insertions(+) diff --git a/include/linux/irq_sim.h b/include/linux/irq_sim.h index 630a57e55db6..676bfa0c12b9 100644 --- a/include/linux/irq_sim.h +++ b/include/linux/irq_sim.h @@ -29,6 +29,7 @@ struct irq_sim { int irq_base; unsigned int irq_count; struct irq_sim_irq_ctx *irqs; + struct mutex lock; }; int irq_sim_init(struct irq_sim *sim, unsigned int num_irqs); diff --git a/kernel/irq/irq_sim.c b/kernel/irq/irq_sim.c index dd20d0d528d4..2f06c24b51a0 100644 --- a/kernel/irq/irq_sim.c +++ b/kernel/irq/irq_sim.c @@ -74,6 +74,7 @@ int irq_sim_init(struct irq_sim *sim, unsigned int num_irqs) } init_irq_work(&sim->work_ctx.work, irq_sim_handle_irq); + mutex_init(&sim->lock); sim->irq_count = num_irqs; return sim->irq_base; @@ -142,10 +143,14 @@ EXPORT_SYMBOL_GPL(devm_irq_sim_init); */ void irq_sim_fire(struct irq_sim *sim, unsigned int offset) { + mutex_lock(&sim->lock); + if (sim->irqs[offset].enabled) { sim->work_ctx.irq = irq_sim_irqnum(sim, offset); irq_work_queue(&sim->work_ctx.work); } + + mutex_unlock(&sim->lock); } EXPORT_SYMBOL_GPL(irq_sim_fire); -- 2.19.1