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=-0.8 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS autolearn=no 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 CBE09C433DF for ; Wed, 8 Jul 2020 13:34:08 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 91B3A20786 for ; Wed, 8 Jul 2020 13:34:08 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1729690AbgGHNeH (ORCPT ); Wed, 8 Jul 2020 09:34:07 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:41664 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1729436AbgGHNeG (ORCPT ); Wed, 8 Jul 2020 09:34:06 -0400 X-Greylist: delayed 420 seconds by postgrey-1.37 at lindbergh.monkeyblade.net; Wed, 08 Jul 2020 06:34:06 PDT Received: from mailout1.hostsharing.net (mailout1.hostsharing.net [IPv6:2a01:37:1000::53df:5fcc:0]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 7E0F1C061A0B for ; Wed, 8 Jul 2020 06:34:06 -0700 (PDT) Received: from h08.hostsharing.net (h08.hostsharing.net [83.223.95.28]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (Client CN "*.hostsharing.net", Issuer "COMODO RSA Domain Validation Secure Server CA" (not verified)) by mailout1.hostsharing.net (Postfix) with ESMTPS id 517EB10190FA4; Wed, 8 Jul 2020 15:27:04 +0200 (CEST) Received: from localhost (unknown [87.130.102.138]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits)) (No client certificate requested) by h08.hostsharing.net (Postfix) with ESMTPSA id 0F1416106EC8; Wed, 8 Jul 2020 15:27:04 +0200 (CEST) X-Mailbox-Line: From 40dc1c5997ecc8784fc98706c5321f9d48240310 Mon Sep 17 00:00:00 2001 Message-Id: From: Lukas Wunner Date: Wed, 8 Jul 2020 14:48:47 +0200 Subject: [PATCH 0/3] Fix races on device removal To: Greg Kroah-Hartman Cc: "Rafael J. Wysocki" , Dan Williams , Geert Uytterhoeven , Pantelis Antoniou , Alexander Duyck , Mark Brown , linux-kernel@vger.kernel.org Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Prevent dynamic SPI device addition below a controller which is being removed. To do so, set the controller's "dead" flag using kill_device() (patch [3/3]). Serialize access to a device's "dead" flag with a newly introduced rw_semaphore in lieu of the device_lock to avoid deadlocks occurring with the new use case (patch [2/3]). Add a missing check for the "dead" flag upon driver binding (patch [1/3]). Lukas Wunner (3): driver core: Avoid binding drivers to dead devices driver core: Use rwsem for kill_device() serialization driver core: Avoid adding children below a dead parent drivers/base/base.h | 2 ++ drivers/base/core.c | 47 ++++++++++++++++++++++++++++++++------------ drivers/base/dd.c | 12 ++++++++++- drivers/nvdimm/bus.c | 8 +------- drivers/spi/spi.c | 3 +++ 5 files changed, 51 insertions(+), 21 deletions(-) -- 2.27.0