From patchwork Tue Jul 25 11:39:38 2023 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Igor Mammedov X-Patchwork-Id: 13326338 X-Patchwork-Delegate: bhelgaas@google.com 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 4535BC001E0 for ; Tue, 25 Jul 2023 11:40:53 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S234983AbjGYLkw (ORCPT ); Tue, 25 Jul 2023 07:40:52 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:46922 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S234965AbjGYLkm (ORCPT ); Tue, 25 Jul 2023 07:40:42 -0400 Received: from us-smtp-delivery-124.mimecast.com (us-smtp-delivery-124.mimecast.com [170.10.129.124]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 6A95CA0 for ; Tue, 25 Jul 2023 04:39:52 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=redhat.com; s=mimecast20190719; t=1690285191; h=from:from:reply-to:subject:subject:date:date:message-id:message-id: to:to:cc:cc:mime-version:mime-version:content-type:content-type: content-transfer-encoding:content-transfer-encoding: in-reply-to:in-reply-to:references:references; bh=WOPLGXJyHcm8uItFp881KDB1MO8xx1vwf3DX/HVbIqA=; b=V/DNqq90KrgB4G6+GGNicZUmn7g9tFgsCWcJK7KlTtDcxX4htgU3nxNPRkwoX+t+lmE/HE G6eDeILnKuLCe6tC1xSqYrrLTX+4EImdlRqD12/eHZH+OrqPUbfCK+dxp0PYzgOKpCsO3R prcEaHfBWL5dOXi6tE9OiBjHZYpDGmU= Received: from mimecast-mx02.redhat.com (mimecast-mx02.redhat.com [66.187.233.88]) by relay.mimecast.com with ESMTP with STARTTLS (version=TLSv1.2, cipher=TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384) id us-mta-353-geGf6MLaOEGavSKJSuucHA-1; Tue, 25 Jul 2023 07:39:45 -0400 X-MC-Unique: geGf6MLaOEGavSKJSuucHA-1 Received: from smtp.corp.redhat.com (int-mx02.intmail.prod.int.rdu2.redhat.com [10.11.54.2]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by mimecast-mx02.redhat.com (Postfix) with ESMTPS id EFCF680027F; Tue, 25 Jul 2023 11:39:44 +0000 (UTC) Received: from dell-r430-03.lab.eng.brq2.redhat.com (dell-r430-03.lab.eng.brq2.redhat.com [10.37.153.18]) by smtp.corp.redhat.com (Postfix) with ESMTP id 186844094DC0; Tue, 25 Jul 2023 11:39:43 +0000 (UTC) From: Igor Mammedov To: linux-kernel@vger.kernel.org Cc: terraluna977@gmail.com, bhelgaas@google.com, linux-pci@vger.kernel.org, imammedo@redhat.com, mst@redhat.com Subject: [RFC 3/3] acpipcihp: use __pci_bus_assign_resources() if bus doesn't have bridge Date: Tue, 25 Jul 2023 13:39:38 +0200 Message-Id: <20230725113938.2277420-4-imammedo@redhat.com> In-Reply-To: <20230725113938.2277420-1-imammedo@redhat.com> References: <20230725113938.2277420-1-imammedo@redhat.com> MIME-Version: 1.0 X-Scanned-By: MIMEDefang 3.1 on 10.11.54.2 Precedence: bulk List-ID: X-Mailing-List: linux-pci@vger.kernel.org Commit [1] switched hotplug to pci_assign_unassigned_bridge_resources() which requires bridge being available, however in S3 suspend/resume cycle acpipcihp might receive device check event from firmware and in case bus->self == NULL, it would make kernel crash with NULL pointer dereference. The issue was triggered on Dell Inspiron 7352/0W6WV0 laptop with following sequence: 1. suspend to RAM 2. wake up 3. suspend to RAM. which immediately wakes up and following backtrace is observed: [ 612.277651] BUG: kernel NULL pointer dereference, address: 0000000000000018 [...] [ 612.277735] Call Trace: [ 612.277739] [ 612.277741] ? __die+0x1a/0x60 [ 612.277749] ? page_fault_oops+0x158/0x430 [ 612.277755] ? prb_read_valid+0x12/0x20 [ 612.277759] ? console_unlock+0x4d/0x100 [ 612.277765] ? __irq_work_queue_local+0x27/0x60 [ 612.277771] ? irq_work_queue+0x2b/0x50 [ 612.277776] ? exc_page_fault+0x357/0x600 [ 612.277781] ? dev_printk_emit+0x7e/0xa0 [ 612.277786] ? asm_exc_page_fault+0x22/0x30 [ 612.277792] ? __pfx_pci_conf1_read+0x10/0x10 [ 612.277798] ? pci_assign_unassigned_bridge_resources+0x1f/0x260 [ 612.277804] ? pcibios_allocate_dev_resources+0x3c/0x2a0 [ 612.277809] enable_slot+0x21f/0x3e0 [ 612.277816] acpiphp_hotplug_notify+0x13d/0x260 [ 612.277822] ? __pfx_acpiphp_hotplug_notify+0x10/0x10 [ 612.277827] acpi_device_hotplug+0xbc/0x540 [ 612.277834] acpi_hotplug_work_fn+0x15/0x20 [ 612.277839] process_one_work+0x1f7/0x370 [ 612.277845] worker_thread+0x45/0x3b0 [ 612.277850] ? __pfx_worker_thread+0x10/0x10 [ 612.277854] kthread+0xdc/0x110 [ 612.277860] ? __pfx_kthread+0x10/0x10 [ 612.277866] ret_from_fork+0x28/0x40 [ 612.277871] ? __pfx_kthread+0x10/0x10 [ 612.277876] ret_from_fork_asm+0x1b/0x30 Fix it by reverting to __pci_bus_assign_resources() usage instead of pci_assign_unassigned_bridge_resources() when bus doesn't have bridge assigned to it. 1) 40613da52b13fb21 (PCI: acpiphp: Reassign resources on bridge if necessary) Signed-off-by: Igor Mammedov --- v2: fix inverted bus->self condition --- drivers/pci/hotplug/acpiphp_glue.c | 11 ++++++++++- 1 file changed, 10 insertions(+), 1 deletion(-) diff --git a/drivers/pci/hotplug/acpiphp_glue.c b/drivers/pci/hotplug/acpiphp_glue.c index c0ffb1389fda..816555ab9171 100644 --- a/drivers/pci/hotplug/acpiphp_glue.c +++ b/drivers/pci/hotplug/acpiphp_glue.c @@ -499,6 +499,7 @@ pci_info(bus, "enable_slot bus: bridge: %d, bus->self: %p\n", bridge, bus->self) acpiphp_native_scan_bridge(dev); } } else { + LIST_HEAD(add_list); int max, pass; acpiphp_rescan_slot(slot); @@ -512,10 +513,18 @@ pci_info(bus, "enable_slot bus: bridge: %d, bus->self: %p\n", bridge, bus->self) if (pass && dev->subordinate) { check_hotplug_bridge(slot, dev); pcibios_resource_survey_bus(dev->subordinate); + if (!bus->self) + __pci_bus_size_bridges(dev->subordinate, &add_list); } } } - pci_assign_unassigned_bridge_resources(bus->self); + if (bus->self) { +pci_info(bus->self, "enable_slot: pci_assign_unassigned_bridge_resources:\n"); + pci_assign_unassigned_bridge_resources(bus->self); + } else { +pci_info(bus, "enable_slot: __pci_bus_assign_resources:\n"); + __pci_bus_assign_resources(bus, &add_list, NULL); + } } acpiphp_sanitize_bus(bus);