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=-12.8 required=3.0 tests=BAYES_00, DKIM_ADSP_CUSTOM_MED,DKIM_INVALID,DKIM_SIGNED,FREEMAIL_FORGED_FROMDOMAIN, FREEMAIL_FROM,HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_PATCH,MAILING_LIST_MULTI, SIGNED_OFF_BY,SPF_HELO_NONE,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 E7AA8C433E0 for ; Fri, 31 Jul 2020 12:43:14 +0000 (UTC) Received: from whitealder.osuosl.org (smtp1.osuosl.org [140.211.166.138]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPS id BBB3221D95 for ; Fri, 31 Jul 2020 12:43:14 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=fail reason="signature verification failed" (2048-bit key) header.d=gmail.com header.i=@gmail.com header.b="GMfvm+H2" DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org BBB3221D95 Authentication-Results: mail.kernel.org; dmarc=fail (p=none dis=none) header.from=gmail.com Authentication-Results: mail.kernel.org; spf=pass smtp.mailfrom=linux-kernel-mentees-bounces@lists.linuxfoundation.org Received: from localhost (localhost [127.0.0.1]) by whitealder.osuosl.org (Postfix) with ESMTP id B02FE88627; Fri, 31 Jul 2020 12:43:14 +0000 (UTC) X-Virus-Scanned: amavisd-new at osuosl.org Received: from whitealder.osuosl.org ([127.0.0.1]) by localhost (.osuosl.org [127.0.0.1]) (amavisd-new, port 10024) with ESMTP id QtBrxp5QURgJ; Fri, 31 Jul 2020 12:43:14 +0000 (UTC) Received: from lists.linuxfoundation.org (lf-lists.osuosl.org [140.211.9.56]) by whitealder.osuosl.org (Postfix) with ESMTP id 1156888606; Fri, 31 Jul 2020 12:43:14 +0000 (UTC) Received: from lf-lists.osuosl.org (localhost [127.0.0.1]) by lists.linuxfoundation.org (Postfix) with ESMTP id 0B8DDC004F; Fri, 31 Jul 2020 12:43:14 +0000 (UTC) Received: from whitealder.osuosl.org (smtp1.osuosl.org [140.211.166.138]) by lists.linuxfoundation.org (Postfix) with ESMTP id 37BB3C004D for ; Fri, 31 Jul 2020 12:43:13 +0000 (UTC) Received: from localhost (localhost [127.0.0.1]) by whitealder.osuosl.org (Postfix) with ESMTP id 206CA88606 for ; Fri, 31 Jul 2020 12:43:13 +0000 (UTC) X-Virus-Scanned: amavisd-new at osuosl.org Received: from whitealder.osuosl.org ([127.0.0.1]) by localhost (.osuosl.org [127.0.0.1]) (amavisd-new, port 10024) with ESMTP id SWobge0kYOgF for ; Fri, 31 Jul 2020 12:43:12 +0000 (UTC) X-Greylist: domain auto-whitelisted by SQLgrey-1.7.6 Received: from mail-ej1-f68.google.com (mail-ej1-f68.google.com [209.85.218.68]) by whitealder.osuosl.org (Postfix) with ESMTPS id 03238885D6 for ; Fri, 31 Jul 2020 12:43:11 +0000 (UTC) Received: by mail-ej1-f68.google.com with SMTP id o18so31264004eje.7 for ; Fri, 31 Jul 2020 05:43:11 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20161025; h=from:to:cc:subject:date:message-id:in-reply-to:references; bh=mu3KVS+jjnoE6TtDYHUGs04kgKz7VUXIOhtqaMe4L8k=; b=GMfvm+H2DwlxEhK0B+zbV8ssTcAL/5E/KjNfTanwFqrgfEUOmkR2UszOuUm7NVCrQN H2yKipSG9Y/TmMbjseu0nl0keYDGluJ3fDRpgdZMJeRxgqTstTW1wzvsWGDuVuoDlVaG bFRd5gafMnXo9eD/Euk/xm9KE8aw4gVr92jhqjEGso5l+IGn0sc4KAhJwkE5lN3sZ9Ww tLF3HFcNAuCgtTL7/81bU/WDHJahrvkMneLlHmiZpZgEuiTaOEBcpzcnrcI68OL9WVn+ 6m93gwcBBdMRa2MIn6d7Il9Aus1rFT1xzX9fJLS00rEOMyzvX5yoky8uGiW+iKYQci1j PHKA== 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; bh=mu3KVS+jjnoE6TtDYHUGs04kgKz7VUXIOhtqaMe4L8k=; b=qBLkotfm6nylWJ3fWl0ii7+4Lm39v/+6yzQv81AzB7jn91OuEzWBOY/QSc8j3VNCJo PHJ7BpA+2R7QmBjFRnj1uffsMaQg7Ut7IVmFZdCEKkwjYqTBurZZDKQg+m9gwGNE1mvT naabwy47hYINJYfa3rBG9i4KuHaCdTy5Y8LeQ+v8ZKNmLceWq2huMFwQeqWbarFnKhbS E/vPtXWnI8YZCoKOBZV58hilFLXOreSRRu55pGoRy29lf6dkKiqvf88lkc2naheq82dV og24jW3P5UtTm5CemNaP7cY2svsyorKEePBYmNq1WyMFH0WOvUv/6wmLhWAqS80F02Np xlsg== X-Gm-Message-State: AOAM531IIhIJrymc6rDrDVJRbufOeSf5DCEBvU283l9pYBEeVkNNvl9F ClMERdkTFtRZEuRvsqJ5ojQ= X-Google-Smtp-Source: ABdhPJzFvrIqdL0TTLhGyuFNtlAocl0tVTusk/30IvWSRwDYeEoMZH80mm/NNJqy7fAqpVg+0+r2Gg== X-Received: by 2002:a17:906:26d6:: with SMTP id u22mr4066761ejc.271.1596199390289; Fri, 31 Jul 2020 05:43:10 -0700 (PDT) Received: from net.saheed (95C84E0A.dsl.pool.telekom.hu. [149.200.78.10]) by smtp.gmail.com with ESMTPSA id g23sm8668514ejb.24.2020.07.31.05.43.09 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Fri, 31 Jul 2020 05:43:09 -0700 (PDT) From: "Saheed O. Bolarinwa" To: helgaas@kernel.org Date: Fri, 31 Jul 2020 13:43:26 +0200 Message-Id: <20200731114329.100848-2-refactormyself@gmail.com> X-Mailer: git-send-email 2.18.4 In-Reply-To: <20200731114329.100848-1-refactormyself@gmail.com> References: <20200731114329.100848-1-refactormyself@gmail.com> Cc: "Saheed O. Bolarinwa" , linux-kernel@vger.kernel.org, linux-pci@vger.kernel.org, linux-kernel-mentees@lists.linuxfoundation.org Subject: [Linux-kernel-mentees] [PATCH v4 09/12] PCI/PM: Check if pcie_capability_read_*() reads ~0 X-BeenThere: linux-kernel-mentees@lists.linuxfoundation.org X-Mailman-Version: 2.1.15 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , MIME-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Errors-To: linux-kernel-mentees-bounces@lists.linuxfoundation.org Sender: "Linux-kernel-mentees" On failure pcie_capability_read_*() sets it's last parameter, val to 0. However, with Patch 12/12, it is possible that val is set to ~0 on failure. This would introduce a bug because (x & x) == (~0 & x). Since ~0 is an invalid value in here, Add extra check for ~0 to ensure success or failure. pci_enable_atomic_ops_to_root(): Continue looping through the device heirarchy on failure. pcie_wait_for_link_delay(): Add extra check for ~0 to the condition for breaking out of the loop. Delay only on success otherwise report error and return false. pcie_bandwidth_available(): On read failure move up the device heirarchy and continue. pcie_get_speed_cap(): On read failure, report error and return PCI_SPEED_UNKNOWN Suggested-by: Bjorn Helgaas Signed-off-by: Saheed O. Bolarinwa --- drivers/pci/pci.c | 34 ++++++++++++++++++++++++---------- 1 file changed, 24 insertions(+), 10 deletions(-) diff --git a/drivers/pci/pci.c b/drivers/pci/pci.c index c9338f914a0e..1dd3659f1388 100644 --- a/drivers/pci/pci.c +++ b/drivers/pci/pci.c @@ -3216,7 +3216,7 @@ void pci_configure_ari(struct pci_dev *dev) return; pcie_capability_read_dword(bridge, PCI_EXP_DEVCAP2, &cap); - if (!(cap & PCI_EXP_DEVCAP2_ARI)) + if ((cap == (u32)~0) || !(cap & PCI_EXP_DEVCAP2_ARI)) return; if (pci_find_ext_capability(dev, PCI_EXT_CAP_ID_ARI)) { @@ -3635,13 +3635,13 @@ int pci_enable_atomic_ops_to_root(struct pci_dev *dev, u32 cap_mask) /* Ensure switch ports support AtomicOp routing */ case PCI_EXP_TYPE_UPSTREAM: case PCI_EXP_TYPE_DOWNSTREAM: - if (!(cap & PCI_EXP_DEVCAP2_ATOMIC_ROUTE)) + if ((cap == (u32)~0) || !(cap & PCI_EXP_DEVCAP2_ATOMIC_ROUTE)) return -EINVAL; break; /* Ensure root port supports all the sizes we care about */ case PCI_EXP_TYPE_ROOT_PORT: - if ((cap & cap_mask) != cap_mask) + if ((cap == (u32)~0) || ((cap & cap_mask) != cap_mask) return -EINVAL; break; } @@ -3650,7 +3650,7 @@ int pci_enable_atomic_ops_to_root(struct pci_dev *dev, u32 cap_mask) if (pci_pcie_type(bridge) == PCI_EXP_TYPE_UPSTREAM) { pcie_capability_read_dword(bridge, PCI_EXP_DEVCTL2, &ctl2); - if (ctl2 & PCI_EXP_DEVCTL2_ATOMIC_EGRESS_BLOCK) + if ((ctl2 != (u32)~0) && (ctl2 & PCI_EXP_DEVCTL2_ATOMIC_EGRESS_BLOCK)) return -EINVAL; } @@ -4512,7 +4512,7 @@ bool pcie_has_flr(struct pci_dev *dev) return false; pcie_capability_read_dword(dev, PCI_EXP_DEVCAP, &cap); - return cap & PCI_EXP_DEVCAP_FLR; + return ((cap != (u32)~0) && (cap & PCI_EXP_DEVCAP_FLR)); } EXPORT_SYMBOL_GPL(pcie_has_flr); @@ -4672,19 +4672,19 @@ static bool pcie_wait_for_link_delay(struct pci_dev *pdev, bool active, for (;;) { pcie_capability_read_word(pdev, PCI_EXP_LNKSTA, &lnk_status); ret = !!(lnk_status & PCI_EXP_LNKSTA_DLLLA); - if (ret == active) + if ((lnk_status != (u16)~0) && (ret == active)) break; if (timeout <= 0) break; msleep(10); timeout -= 10; } - if (active && ret) + if ((lnk_status != (u16)~0) && active && ret) msleep(delay); - else if (ret != active) + else if ((lnk_status == (u16)~0) || (ret != active)) pci_info(pdev, "Data Link Layer Link Active not %s in 1000 msec\n", active ? "set" : "cleared"); - return ret == active; + return ((lnk_status != (u16)~0) && (ret == active)); } /** @@ -5773,6 +5773,11 @@ u32 pcie_bandwidth_available(struct pci_dev *dev, struct pci_dev **limiting_dev, while (dev) { pcie_capability_read_word(dev, PCI_EXP_LNKSTA, &lnksta); + if (lnksta == (u16)~0) { + dev = pci_upstream_bridge(dev); + continue; + } + next_speed = pcie_link_speed[lnksta & PCI_EXP_LNKSTA_CLS]; next_width = (lnksta & PCI_EXP_LNKSTA_NLW) >> PCI_EXP_LNKSTA_NLW_SHIFT; @@ -5819,12 +5824,21 @@ enum pci_bus_speed pcie_get_speed_cap(struct pci_dev *dev) * where only 2.5 GT/s and 5.0 GT/s speeds were defined. */ pcie_capability_read_dword(dev, PCI_EXP_LNKCAP2, &lnkcap2); + if (lnkcap2 == (u32)~0) { + dev_err(dev, "Read link speed capability has failed.\n"); + return PCI_SPEED_UNKNOWN; + } /* PCIe r3.0-compliant */ if (lnkcap2) return PCIE_LNKCAP2_SLS2SPEED(lnkcap2); pcie_capability_read_dword(dev, PCI_EXP_LNKCAP, &lnkcap); + if (lnkcap == (u32)~0) { + dev_err(dev, "Read link speed capability has failed.\n"); + return PCI_SPEED_UNKNOWN; + } + if ((lnkcap & PCI_EXP_LNKCAP_SLS) == PCI_EXP_LNKCAP_SLS_5_0GB) return PCIE_SPEED_5_0GT; else if ((lnkcap & PCI_EXP_LNKCAP_SLS) == PCI_EXP_LNKCAP_SLS_2_5GB) @@ -5846,7 +5860,7 @@ enum pcie_link_width pcie_get_width_cap(struct pci_dev *dev) u32 lnkcap; pcie_capability_read_dword(dev, PCI_EXP_LNKCAP, &lnkcap); - if (lnkcap) + if (lnkcap && (lnkcap != (u32)~0)) return (lnkcap & PCI_EXP_LNKCAP_MLW) >> 4; return PCIE_LNK_WIDTH_UNKNOWN; -- 2.18.4 _______________________________________________ Linux-kernel-mentees mailing list Linux-kernel-mentees@lists.linuxfoundation.org https://lists.linuxfoundation.org/mailman/listinfo/linux-kernel-mentees