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 Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id 350A3C76196 for ; Tue, 28 Mar 2023 13:32:23 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S233264AbjC1NcW (ORCPT ); Tue, 28 Mar 2023 09:32:22 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:54174 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S233296AbjC1NcK (ORCPT ); Tue, 28 Mar 2023 09:32:10 -0400 Received: from dfw.source.kernel.org (dfw.source.kernel.org [IPv6:2604:1380:4641:c500::1]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 5404ECA2A; Tue, 28 Mar 2023 06:31:46 -0700 (PDT) Received: from smtp.kernel.org (relay.kernel.org [52.25.139.140]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by dfw.source.kernel.org (Postfix) with ESMTPS id BA6B1616F0; Tue, 28 Mar 2023 13:31:45 +0000 (UTC) Received: by smtp.kernel.org (Postfix) with ESMTPSA id 2CC97C4339C; Tue, 28 Mar 2023 13:31:45 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1680010305; bh=nrDhBG7YSqdUTZAK8NjLiILzcTDoY0sT0uFjd2gzc+k=; h=References:In-Reply-To:From:Date:Subject:To:Cc:From; b=CKeT2tkeXkhFB8flK0TF45FmW3lWHiWhzKVjRFb+QteA3qYX9mfo+OcTDzcym58P9 h3hM2ScsbHSByx+xRt6pctMZf8ntPkKVUgkHLiU4MpwtFKiYQ7Im0/LcPG5cEUvLE6 BHxzSWGn4MQ4EYiMD6wBdaNgOhK6tU6YZ/GpK4wg3iny+2MZgJwmjuZ6DS7GN+DUuw uAO7vFL1NjPil37dZ8beI1qhvy3zrKwTK5qB4ljVQUhnOAZ3QkAiAz/g83u5HTkhCg AQGnnWF5zQwyYJTnuJNVPk9UVjWwMJQRYmhAtv17yF9zc4RgSTwlzCJhRfzdnNf0KT O2ZXao2sjQeUw== Received: by mail-yw1-f169.google.com with SMTP id 00721157ae682-5419d4c340aso229506597b3.11; Tue, 28 Mar 2023 06:31:45 -0700 (PDT) X-Gm-Message-State: AAQBX9clt73CEmyV7Z1BpykTQdfaVZW4Ssu1ZtorZxjeAk6pOL1N8Yat /geAzU3t7N2wGwhIMYGUSYyIO+nanv2n1La4vQ== X-Google-Smtp-Source: AKy350adGUM1TIDE6jPN4w068hh35P4yTPslWKdtfQlrHglx6bkc9oWCDCOPHeOWPWU+0UuYolz0WEMJpGIHwbzfryI= X-Received: by 2002:a81:a908:0:b0:545:7164:49ac with SMTP id g8-20020a81a908000000b00545716449acmr7116719ywh.5.1680010304089; Tue, 28 Mar 2023 06:31:44 -0700 (PDT) MIME-Version: 1.0 References: <20220702204737.7719-1-pali@kernel.org> <20220714184130.5436-1-pali@kernel.org> <20230320205936.wd6pj3trljsduj5c@pali> <993ca7dc-1d39-6ae9-1033-838d81aeb076@nvidia.com> <3414723d-7d79-809f-e63f-35243d945b50@nvidia.com> In-Reply-To: <3414723d-7d79-809f-e63f-35243d945b50@nvidia.com> From: Rob Herring Date: Tue, 28 Mar 2023 08:31:32 -0500 X-Gmail-Original-Message-ID: Message-ID: Subject: Re: [PATCH v2] PCI: Assign PCI domain by ida_alloc() To: Jon Hunter Cc: =?UTF-8?Q?Pali_Roh=C3=A1r?= , Bjorn Helgaas , Andrew Lunn , =?UTF-8?B?TWFyZWsgQmVow7pu?= , linux-pci@vger.kernel.org, linux-kernel@vger.kernel.org, "linux-tegra@vger.kernel.org" Content-Type: text/plain; charset="UTF-8" Content-Transfer-Encoding: quoted-printable Precedence: bulk List-ID: X-Mailing-List: linux-tegra@vger.kernel.org On Wed, Mar 22, 2023 at 9:36=E2=80=AFAM Jon Hunter w= rote: > > > On 21/03/2023 18:44, Jon Hunter wrote: > > > > On 20/03/2023 20:59, Pali Roh=C3=A1r wrote: > >> Hello! > >> > >> On Monday 20 March 2023 20:26:05 Jon Hunter wrote: > >>> Hi Pali, > >>> > >>> After this change was made we are seeing the following bug > >>> report on a Tegra234 Jetson Orin board ... > >>> > >>> [ 17.172346] tegra194-pcie 141a0000.pcie: host bridge > >>> /pcie@141a0000 ranges: > >>> [ 17.172470] tegra194-pcie 141a0000.pcie: MEM > >>> 0x2800000000..0x2b27ffffff -> 0x2800000000 > >>> [ 17.172519] tegra194-pcie 141a0000.pcie: MEM > >>> 0x2b28000000..0x2b2fffffff -> 0x0040000000 > >>> [ 17.172548] tegra194-pcie 141a0000.pcie: IO > >>> 0x003a100000..0x003a1fffff -> 0x003a100000 > >>> [ 17.173449] tegra194-pcie 141a0000.pcie: iATU: unroll T, 8 ob, 2 > >>> ib, align 64K, limit 32G > >>> [ 18.279048] tegra194-pcie 141a0000.pcie: Phy link never came up > >>> [ 19.279285] tegra194-pcie 141a0000.pcie: Phy link never came up > >>> [ 19.279599] tegra194-pcie 141a0000.pcie: PCI host bridge to bus > >>> 0005:00 > >>> [ 19.279613] pci_bus 0005:00: root bus resource [bus 00-ff] > >>> [ 19.279622] pci_bus 0005:00: root bus resource [mem > >>> 0x2800000000-0x2b27ffffff pref] > >>> [ 19.279631] pci_bus 0005:00: root bus resource [mem > >>> 0x2b28000000-0x2b2fffffff] (bus address [0x40000000-0x47ffffff]) > >>> [ 19.279639] pci_bus 0005:00: root bus resource [io > >>> 0x200000-0x2fffff] (bus address [0x3a100000-0x3a1fffff]) > >>> [ 19.279687] pci 0005:00:00.0: [10de:229a] type 01 class 0x060400 > >>> [ 19.279886] pci 0005:00:00.0: PME# supported from D0 D3hot > >>> [ 19.283256] pci 0005:00:00.0: PCI bridge to [bus 01-ff] > >>> [ 19.283590] pcieport 0005:00:00.0: Adding to iommu group 26 > >>> [ 19.283991] pcieport 0005:00:00.0: PME: Signaling with IRQ 174 > >>> [ 19.284429] pcieport 0005:00:00.0: AER: enabled with IRQ 174 > >>> [ 19.285003] pci_bus 0005:01: busn_res: [bus 01-ff] is released > >>> [ 19.285591] pci 0005:00:00.0: Removing from iommu group 26 > >>> [ 19.285751] pci_bus 0005:00: busn_res: [bus 00-ff] is released > >>> [ 19.285870] > >>> =3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D= =3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D= =3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D > >>> [ 19.293351] BUG: KFENCE: use-after-free read in > >>> pci_bus_release_domain_nr+0x10/0x70 > >>> > >>> [ 19.302817] Use-after-free read at 0x000000007f3b80eb (in > >>> kfence-#115): > >>> [ 19.309677] pci_bus_release_domain_nr+0x10/0x70 > >>> [ 19.309691] dw_pcie_host_deinit+0x28/0x78 > >>> [ 19.309702] tegra_pcie_deinit_controller+0x1c/0x38 [pcie_tegra194= ] > >>> [ 19.309734] tegra_pcie_dw_probe+0x648/0xb28 [pcie_tegra194] > >>> [ 19.309752] platform_probe+0x90/0xd8 > >>> [ 19.309764] really_probe+0xb8/0x298 > >>> [ 19.309777] __driver_probe_device+0x78/0xd8 > >>> [ 19.309788] driver_probe_device+0x38/0x120 > >>> [ 19.309799] __device_attach_driver+0x94/0xe0 > >>> [ 19.309812] bus_for_each_drv+0x70/0xc8 > >>> [ 19.309822] __device_attach+0xfc/0x188 > >>> [ 19.309833] device_initial_probe+0x10/0x18 > >>> [ 19.309844] bus_probe_device+0x94/0xa0 > >>> [ 19.309854] deferred_probe_work_func+0x80/0xb8 > >>> [ 19.309864] process_one_work+0x1e0/0x348 > >>> [ 19.309882] worker_thread+0x48/0x410 > >>> [ 19.309891] kthread+0xf4/0x110 > >>> [ 19.309904] ret_from_fork+0x10/0x20 > >>> > >>> [ 19.311457] kfence-#115: 0x00000000063a155a-0x00000000ba698da8, > >>> size=3D1072, cache=3Dkmalloc-2k > >>> > >>> [ 19.311469] allocated by task 96 on cpu 10 at 19.279323s: > >>> [ 19.311562] __kmem_cache_alloc_node+0x260/0x278 > >>> [ 19.311571] kmalloc_trace+0x24/0x30 > >>> [ 19.311580] pci_alloc_bus+0x24/0xa0 > >>> [ 19.311590] pci_register_host_bridge+0x48/0x4b8 > >>> [ 19.311601] pci_scan_root_bus_bridge+0xc0/0xe8 > >>> [ 19.311613] pci_host_probe+0x18/0xc0 > >>> [ 19.311623] dw_pcie_host_init+0x2c0/0x568 > >>> [ 19.311630] tegra_pcie_dw_probe+0x610/0xb28 [pcie_tegra194] > >>> [ 19.311647] platform_probe+0x90/0xd8 > >>> [ 19.311653] really_probe+0xb8/0x298 > >>> [ 19.311663] __driver_probe_device+0x78/0xd8 > >>> [ 19.311672] driver_probe_device+0x38/0x120 > >>> [ 19.311682] __device_attach_driver+0x94/0xe0 > >>> [ 19.311694] bus_for_each_drv+0x70/0xc8 > >>> [ 19.311702] __device_attach+0xfc/0x188 > >>> [ 19.311713] device_initial_probe+0x10/0x18 > >>> [ 19.311724] bus_probe_device+0x94/0xa0 > >>> [ 19.311733] deferred_probe_work_func+0x80/0xb8 > >>> [ 19.311743] process_one_work+0x1e0/0x348 > >>> [ 19.311753] worker_thread+0x48/0x410 > >>> [ 19.311763] kthread+0xf4/0x110 > >>> [ 19.311771] ret_from_fork+0x10/0x20 > >>> > >>> [ 19.311782] freed by task 96 on cpu 10 at 19.285833s: > >>> [ 19.311799] release_pcibus_dev+0x30/0x40 > >>> [ 19.311808] device_release+0x30/0x90 > >>> [ 19.311814] kobject_put+0xa8/0x120 > >>> [ 19.311832] device_unregister+0x20/0x30 > >>> [ 19.311839] pci_remove_bus+0x78/0x88 > >>> [ 19.311850] pci_remove_root_bus+0x5c/0x98 > >>> [ 19.311860] dw_pcie_host_deinit+0x28/0x78 > >>> [ 19.311866] tegra_pcie_deinit_controller+0x1c/0x38 [pcie_tegra194= ] > >>> [ 19.311883] tegra_pcie_dw_probe+0x648/0xb28 [pcie_tegra194] > >>> [ 19.311900] platform_probe+0x90/0xd8 > >>> [ 19.311906] really_probe+0xb8/0x298 > >>> [ 19.311916] __driver_probe_device+0x78/0xd8 > >>> [ 19.311926] driver_probe_device+0x38/0x120 > >>> [ 19.311936] __device_attach_driver+0x94/0xe0 > >>> [ 19.311947] bus_for_each_drv+0x70/0xc8 > >>> [ 19.311956] __device_attach+0xfc/0x188 > >>> [ 19.311966] device_initial_probe+0x10/0x18 > >>> [ 19.311976] bus_probe_device+0x94/0xa0 > >>> [ 19.311985] deferred_probe_work_func+0x80/0xb8 > >>> [ 19.311995] process_one_work+0x1e0/0x348 > >>> [ 19.312005] worker_thread+0x48/0x410 > >>> [ 19.312014] kthread+0xf4/0x110 > >>> [ 19.312022] ret_from_fork+0x10/0x20 > >> > >> Based on the above trace it looks like a double free of "pp->bridge" > >> structure. > >> > >> Also, which kernel version are you using? Because from above third > >> trace it looks like that dw_pcie_host_deinit() calls first > >> pci_remove_root_bus() function and then (from first strace) it also > >> calls pci_bus_release_domain_nr() function. It's all the same stack trace. The struct pci_bus is a struct device which is released first and then accessed by of_pci_bus_release_domain_nr(). > > I have definitely seen this with v6.2. I was doing some more testing an= d > > now it appears that the issue is somewhat intermittent. So now I am n= o > > longer confident that reverting this change does fix it. The backtrace > > made it seem like this is a likely candidate, but I need to do more > > testing. > > > OK, so I have done some more testing. I found that if I build the > Tegra194 PCIe driver into the kernel, then I can reproduce the above > 100%. I guess by loading early there is more chance of a probe deferral. > With that I verified that the issue is seen on v6.2 (as I previously > observed) and on v6.3-rc3. Reverting this commit on top of v6.3-rc3 > fixes this and I no longer see the problem. > > Let me know if you have any thoughts on how to fix this. Does this fix it?: diff --git a/drivers/pci/remove.c b/drivers/pci/remove.c index 0145aef1b930..22d39e12b236 100644 --- a/drivers/pci/remove.c +++ b/drivers/pci/remove.c @@ -157,8 +157,6 @@ void pci_remove_root_bus(struct pci_bus *bus) list_for_each_entry_safe(child, tmp, &bus->devices, bus_list) pci_remove_bus_device(child); - pci_remove_bus(bus); - host_bridge->bus =3D NULL; #ifdef CONFIG_PCI_DOMAINS_GENERIC /* Release domain_nr if it was dynamically allocated */ @@ -166,6 +164,9 @@ void pci_remove_root_bus(struct pci_bus *bus) pci_bus_release_domain_nr(bus, host_bridge->dev.parent); #endif + pci_remove_bus(bus); + host_bridge->bus =3D NULL; + /* remove the host bridge */ device_del(&host_bridge->dev); }