From patchwork Thu Jul 11 23:44:00 2019 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Joel Fernandes X-Patchwork-Id: 11040969 Return-Path: Received: from mail.wl.linuxfoundation.org (pdx-wl-mail.web.codeaurora.org [172.30.200.125]) by pdx-korg-patchwork-2.web.codeaurora.org (Postfix) with ESMTP id D3921138B for ; Thu, 11 Jul 2019 23:45:09 +0000 (UTC) Received: from mail.wl.linuxfoundation.org (localhost [127.0.0.1]) by mail.wl.linuxfoundation.org (Postfix) with ESMTP id C3C0128B8A for ; Thu, 11 Jul 2019 23:45:09 +0000 (UTC) Received: by mail.wl.linuxfoundation.org (Postfix, from userid 486) id B6A4C28B90; Thu, 11 Jul 2019 23:45:09 +0000 (UTC) X-Spam-Checker-Version: SpamAssassin 3.3.1 (2010-03-16) on pdx-wl-mail.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-5.3 required=2.0 tests=BAYES_00,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,MAILING_LIST_MULTI,RCVD_IN_DNSWL_MED autolearn=ham version=3.3.1 Received: from mother.openwall.net (mother.openwall.net [195.42.179.200]) by mail.wl.linuxfoundation.org (Postfix) with SMTP id BBF9B28B8A for ; Thu, 11 Jul 2019 23:45:08 +0000 (UTC) Received: (qmail 13413 invoked by uid 550); 11 Jul 2019 23:44:46 -0000 Mailing-List: contact kernel-hardening-help@lists.openwall.com; run by ezmlm Precedence: bulk List-Post: List-Help: List-Unsubscribe: List-Subscribe: List-ID: Delivered-To: mailing list kernel-hardening@lists.openwall.com Received: (qmail 13323 invoked from network); 11 Jul 2019 23:44:45 -0000 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=joelfernandes.org; s=google; h=from:to:cc:subject:date:message-id:in-reply-to:references :mime-version:content-transfer-encoding; bh=2ZIVHYCgJL3yRIi6SYczqkcDc7iwVPEmctKSmd2Crvc=; b=weyT2Xtq2vSltoDfjRS7QyAHHP5rgF8+biSlRsYiS8lJ0ThTHGlPYRoWyR8jXC62XM l5SwCMDem7+8P/pejjNL1kUvgWDcvhvqPo2nGj5eahzpfUT6jCwtf4+D4JJiDwbxZ585 8qs6F1/k7sh09QSdaz8CSnrGSPZzQbFmNT4a4= 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:in-reply-to :references:mime-version:content-transfer-encoding; bh=2ZIVHYCgJL3yRIi6SYczqkcDc7iwVPEmctKSmd2Crvc=; b=aKsK9ptdkv4m4gnrN7+X1AsPbHUrgF2TOj0VAL3XKzGKMabNQwE55CaUOjCL9cyCi6 Wc72ASrehc9HZsrbanl4jW7XPRS38DubEiCng7CUYfeneOfNlfjDOQsKpPHWm4u8JrnD ZmiwamyCVFOF6RqE3hpj1XMce9D5Bgd3UP2zq4OujJpiPz2tK1BWJNbkmAB4vE1fpPej mwS9hR5VmWzYH1bjTkBB/NMxZFmRCqssmL+YGEioCftfY+D5bPkDORg3aKiT7yNdKle0 Mpnc2rOCpOGNDt9fTvTmHi+yLMvCyfEOCfsNH/wkL9utCJNPkh3SqTNS2cut+GbWFarh HYkg== X-Gm-Message-State: APjAAAUbIouEVp6V1lsXlGLHYkYIH1tuNpW67ohS/OwBU0V0KkT7gjs2 OjyrclVr12Eb08eGbAKvu6I= X-Google-Smtp-Source: APXvYqxf45Rt48qewS/1TxXy9teNni48bxwe3+YaybaZjyCTXYiBUvRLNPvO6nnYPvEQInHLi90qmA== X-Received: by 2002:a17:90a:3aed:: with SMTP id b100mr7900731pjc.63.1562888673741; Thu, 11 Jul 2019 16:44:33 -0700 (PDT) From: "Joel Fernandes (Google)" To: linux-kernel@vger.kernel.org Cc: "Joel Fernandes (Google)" , Alexey Kuznetsov , Bjorn Helgaas , Borislav Petkov , c0d1n61at3@gmail.com, "David S. Miller" , edumazet@google.com, Greg Kroah-Hartman , Hideaki YOSHIFUJI , "H. Peter Anvin" , Ingo Molnar , Josh Triplett , keescook@chromium.org, kernel-hardening@lists.openwall.com, Lai Jiangshan , Len Brown , linux-acpi@vger.kernel.org, linux-pci@vger.kernel.org, linux-pm@vger.kernel.org, Mathieu Desnoyers , neilb@suse.com, netdev@vger.kernel.org, oleg@redhat.com, "Paul E. McKenney" , Pavel Machek , peterz@infradead.org, "Rafael J. Wysocki" , Rasmus Villemoes , rcu@vger.kernel.org, Steven Rostedt , Tejun Heo , Thomas Gleixner , will@kernel.org, x86@kernel.org (maintainer:X86 ARCHITECTURE (32-BIT AND 64-BIT)) Subject: [PATCH v1 5/6] x86/pci: Pass lockdep condition to pcm_mmcfg_list iterator Date: Thu, 11 Jul 2019 19:44:00 -0400 Message-Id: <20190711234401.220336-6-joel@joelfernandes.org> X-Mailer: git-send-email 2.22.0.410.gd8fdbe21b5-goog In-Reply-To: <20190711234401.220336-1-joel@joelfernandes.org> References: <20190711234401.220336-1-joel@joelfernandes.org> MIME-Version: 1.0 X-Virus-Scanned: ClamAV using ClamSMTP The pcm_mmcfg_list is traversed with list_for_each_entry_rcu without a reader-lock held, because the pci_mmcfg_lock is already held. Make this known to the list macro so that it fixes new lockdep warnings that trigger due to lockdep checks added to list_for_each_entry_rcu(). Signed-off-by: Joel Fernandes (Google) --- arch/x86/pci/mmconfig-shared.c | 5 +++-- 1 file changed, 3 insertions(+), 2 deletions(-) diff --git a/arch/x86/pci/mmconfig-shared.c b/arch/x86/pci/mmconfig-shared.c index 7389db538c30..6fa42e9c4e6f 100644 --- a/arch/x86/pci/mmconfig-shared.c +++ b/arch/x86/pci/mmconfig-shared.c @@ -29,6 +29,7 @@ static bool pci_mmcfg_running_state; static bool pci_mmcfg_arch_init_failed; static DEFINE_MUTEX(pci_mmcfg_lock); +#define pci_mmcfg_lock_held() lock_is_held(&(pci_mmcfg_lock).dep_map) LIST_HEAD(pci_mmcfg_list); @@ -54,7 +55,7 @@ static void list_add_sorted(struct pci_mmcfg_region *new) struct pci_mmcfg_region *cfg; /* keep list sorted by segment and starting bus number */ - list_for_each_entry_rcu(cfg, &pci_mmcfg_list, list) { + list_for_each_entry_rcu(cfg, &pci_mmcfg_list, list, pci_mmcfg_lock_held()) { if (cfg->segment > new->segment || (cfg->segment == new->segment && cfg->start_bus >= new->start_bus)) { @@ -118,7 +119,7 @@ struct pci_mmcfg_region *pci_mmconfig_lookup(int segment, int bus) { struct pci_mmcfg_region *cfg; - list_for_each_entry_rcu(cfg, &pci_mmcfg_list, list) + list_for_each_entry_rcu(cfg, &pci_mmcfg_list, list, pci_mmcfg_lock_held()) if (cfg->segment == segment && cfg->start_bus <= bus && bus <= cfg->end_bus) return cfg;