mirror of https://lore.kernel.org/lkml/
 help / color / mirror / Atom feed
From: Ding Tianhong <dingtianhong@huawei.com>
To: Eric Dumazet <eric.dumazet@gmail.com>,
	David Miller <davem@davemloft.net>
Cc: <leedom@chelsio.com>, <ashok.raj@intel.com>,
	<bhelgaas@google.com>, <helgaas@kernel.org>, <werner@chelsio.com>,
	<ganeshgr@chelsio.com>, <asit.k.mallick@intel.com>,
	<patrick.j.cramer@intel.com>, <Suravee.Suthikulpanit@amd.com>,
	<Bob.Shaw@amd.com>, <l.stach@pengutronix.de>,
	<amira@mellanox.com>, <gabriele.paoloni@huawei.com>,
	<David.Laight@aculab.com>, <jeffrey.t.kirsher@intel.com>,
	<catalin.marinas@arm.com>, <will.deacon@arm.com>,
	<mark.rutland@arm.com>, <robin.murphy@arm.com>,
	<alexander.duyck@gmail.com>,
	<linux-arm-kernel@lists.infradead.org>, <netdev@vger.kernel.org>,
	<linux-pci@vger.kernel.org>, <linux-kernel@vger.kernel.org>,
	<linuxarm@huawei.com>
Subject: Re: [PATCH v11 0/5] Add new PCI_DEV_FLAGS_NO_RELAXED_ORDERING flag
Date: Tue, 15 Aug 2017 22:45:00 +0800	[thread overview]
Message-ID: <79546d64-ea06-1723-4433-c990bda40a5b@huawei.com> (raw)
In-Reply-To: <1502805794.4936.75.camel@edumazet-glaptop3.roam.corp.google.com>



On 2017/8/15 22:03, Eric Dumazet wrote:
> On Tue, 2017-08-15 at 06:58 -0700, Eric Dumazet wrote:
>> On Mon, 2017-08-14 at 22:15 -0700, David Miller wrote:
>>> From: Ding Tianhong <dingtianhong@huawei.com>
>>> Date: Tue, 15 Aug 2017 11:23:22 +0800
>>>
>>>> Some devices have problems with Transaction Layer Packets with the Relaxed
>>>> Ordering Attribute set.  This patch set adds a new PCIe Device Flag,
>>>> PCI_DEV_FLAGS_NO_RELAXED_ORDERING, a set of PCI Quirks to catch some known
>>>> devices with Relaxed Ordering issues, and a use of this new flag by the
>>>> cxgb4 driver to avoid using Relaxed Ordering with problematic Root Complex
>>>> Ports.
>>>  ...
>>>
>>> Series applied, thanks.
>>
>> I got a NULL deref in pci_find_pcie_root_port()
>>
> 
> This was :
> 
> [    4.241029] BUG: unable to handle kernel NULL pointer dereference at 0000000000000050
> [    4.247001] IP: pci_find_pcie_root_port+0x62/0x80
> [    4.253011] PGD 0 
> [    4.253011] P4D 0 
> [    4.253011] 
> [    4.258013] Oops: 0000 [#1] SMP DEBUG_PAGEALLOC
> [    4.262015] Modules linked in:
> [    4.265005] CPU: 31 PID: 1 Comm: swapper/0 Not tainted 4.13.0-dbx-DEV #316
> [    4.271002] Hardware name: Intel RML,PCH/Iota_QC_19, BIOS 2.40.0 06/22/2016
> [    4.279002] task: ffffa2ee38cfa040 task.stack: ffffa51ec0004000
> [    4.285001] RIP: 0010:pci_find_pcie_root_port+0x62/0x80
> [    4.290012] RSP: 0000:ffffa51ec0007ab8 EFLAGS: 00010246
> [    4.295003] RAX: 0000000000000000 RBX: ffffa2ee36bae000 RCX: 0000000000000006
> [    4.303002] RDX: 000000000000081c RSI: ffffa2ee38cfa8c8 RDI: ffffa2ee36bae000
> [    4.310013] RBP: ffffa51ec0007b58 R08: 0000000000000001 R09: 0000000000000000
> [    4.317001] R10: 0000000000000000 R11: 0000000000000000 R12: ffffa51ec0007ad0
> [    4.324005] R13: ffffa2ee36bae098 R14: 0000000000000002 R15: ffffa2ee37204818
> [    4.331002] FS:  0000000000000000(0000) GS:ffffa2ee3fcc0000(0000) knlGS:0000000000000000
> [    4.339002] CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
> [    4.345001] CR2: 0000000000000050 CR3: 000000401000f000 CR4: 00000000001406e0
> [    4.351002] Call Trace:
> [    4.354012]  ? pci_configure_device+0x19f/0x570
> [    4.359002]  ? pci_conf1_read+0xb8/0xf0
> [    4.363002]  ? raw_pci_read+0x23/0x40
> [    4.366011]  ? pci_read+0x2c/0x30
> [    4.370014]  ? pci_read_config_word+0x67/0x70
> [    4.374012]  pci_device_add+0x28/0x230
> [    4.378012]  ? pci_vpd_f0_read+0x50/0x80
> [    4.382014]  pci_scan_single_device+0x96/0xc0
> [    4.386012]  pci_scan_slot+0x79/0xf0
> [    4.389001]  pci_scan_child_bus+0x31/0x180
> [    4.394014]  acpi_pci_root_create+0x1c6/0x240
> [    4.398013]  pci_acpi_scan_root+0x15f/0x1b0
> [    4.402012]  acpi_pci_root_add+0x2e6/0x400
> [    4.406012]  ? acpi_evaluate_integer+0x37/0x60
> [    4.411002]  acpi_bus_attach+0xdf/0x200
> [    4.415002]  acpi_bus_attach+0x6a/0x200
> [    4.418014]  acpi_bus_attach+0x6a/0x200
> [    4.422013]  acpi_bus_scan+0x38/0x70
> [    4.426011]  acpi_scan_init+0x10c/0x271
> [    4.429001]  acpi_init+0x2fa/0x348
> [    4.433004]  ? acpi_sleep_proc_init+0x2d/0x2d
> [    4.437001]  do_one_initcall+0x43/0x169
> [    4.441001]  kernel_init_freeable+0x1d0/0x258
> [    4.445003]  ? rest_init+0xe0/0xe0
> [    4.449001]  kernel_init+0xe/0x150
> [    4.451002]  ret_from_fork+0x27/0x40
> [    4.457004] Code: 85 d2 74 27 80 7a 4a 00 74 21 48 89 d0 48 89 c2 f6 80 1b 09 00 00 10 74 07 48 8b 90 a0 0a 00 00 48 8b 52 10 48 83 7a 10 00 75 d0 <0f> b7 50 50 5d 81 e2 f0 00 00 00 83 fa 40 ba 00 00 00 00 48 0f 
> [    4.474012] RIP: pci_find_pcie_root_port+0x62/0x80 RSP: ffffa51ec0007ab8
> [    4.481004] CR2: 0000000000000050
> [    4.484001] ---[ end trace 6f9be6a057581199 ]---
> [    4.488001] Kernel panic - not syncing: Fatal exception
> [    4.494013] Rebooting in 10 seconds..
> [    4.494013] ACPI MEMORY or I/O RESET_REG.
> 
>>
>> This local hack seems to fix the issue.
>>
>> diff --git a/drivers/pci/pci.c b/drivers/pci/pci.c
>> index af0cc3456dc1b48b1325c06c5edd2ca8cc22a640..cfd8eb5a3d0ba8347d44952ffab28d9c761044d3 100644
>> --- a/drivers/pci/pci.c
>> +++ b/drivers/pci/pci.c
>> @@ -522,7 +522,7 @@ struct pci_dev *pci_find_pcie_root_port(struct pci_dev *dev)
>>                 bridge = pci_upstream_bridge(bridge);
>>         }
>>  
>> -       if (pci_pcie_type(highest_pcie_bridge) != PCI_EXP_TYPE_ROOT_PORT)
>> +       if (highest_pcie_bridge && pci_pcie_type(highest_pcie_bridge) != PCI_EXP_TYPE_ROOT_PORT)
>>                 return NULL;
>>  
>>         return highest_pcie_bridge;
> 

It is very strange that I could not reproduce this problem on my server which is Xeon 2690v3,
but it is really a obviously issue when the dev could not find a upstream bridge in the
pci_find_pcie_root_port(), so the better way is just like your did in this patch. Thanks.

Regards
Tianhong

> 
> 
> .
> 

      reply	other threads:[~2017-08-15 14:49 UTC|newest]

Thread overview: 10+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2017-08-15  3:23 Ding Tianhong
2017-08-15  3:23 ` [PATCH v11 1/5] PCI: Disable PCIe Relaxed Ordering if unsupported Ding Tianhong
2017-08-15  3:23 ` [PATCH v11 2/5] PCI: Disable Relaxed Ordering for some Intel processors Ding Tianhong
2017-08-15  3:23 ` [PATCH v11 3/5] PCI: Disable Relaxed Ordering Attributes for AMD A1100 Ding Tianhong
2017-08-15  3:23 ` [PATCH v11 4/5] net/cxgb4: Use new PCI_DEV_FLAGS_NO_RELAXED_ORDERING flag Ding Tianhong
2017-08-15  3:23 ` [PATCH v11 5/5] net/cxgb4vf: " Ding Tianhong
2017-08-15  5:15 ` [PATCH v11 0/5] Add " David Miller
2017-08-15 13:58   ` Eric Dumazet
2017-08-15 14:03     ` Eric Dumazet
2017-08-15 14:45       ` Ding Tianhong [this message]

Reply instructions:

You may reply publicly to this message via plain-text email
using any one of the following methods:

* Save the following mbox file, import it into your mail client,
  and reply-to-all from there: mbox

  Avoid top-posting and favor interleaved quoting:
  https://en.wikipedia.org/wiki/Posting_style#Interleaved_style

* Reply using the --to, --cc, and --in-reply-to
  switches of git-send-email(1):

  git send-email \
    --in-reply-to=79546d64-ea06-1723-4433-c990bda40a5b@huawei.com \
    --to=dingtianhong@huawei.com \
    --cc=Bob.Shaw@amd.com \
    --cc=David.Laight@aculab.com \
    --cc=Suravee.Suthikulpanit@amd.com \
    --cc=alexander.duyck@gmail.com \
    --cc=amira@mellanox.com \
    --cc=ashok.raj@intel.com \
    --cc=asit.k.mallick@intel.com \
    --cc=bhelgaas@google.com \
    --cc=catalin.marinas@arm.com \
    --cc=davem@davemloft.net \
    --cc=eric.dumazet@gmail.com \
    --cc=gabriele.paoloni@huawei.com \
    --cc=ganeshgr@chelsio.com \
    --cc=helgaas@kernel.org \
    --cc=jeffrey.t.kirsher@intel.com \
    --cc=l.stach@pengutronix.de \
    --cc=leedom@chelsio.com \
    --cc=linux-arm-kernel@lists.infradead.org \
    --cc=linux-kernel@vger.kernel.org \
    --cc=linux-pci@vger.kernel.org \
    --cc=linuxarm@huawei.com \
    --cc=mark.rutland@arm.com \
    --cc=netdev@vger.kernel.org \
    --cc=patrick.j.cramer@intel.com \
    --cc=robin.murphy@arm.com \
    --cc=werner@chelsio.com \
    --cc=will.deacon@arm.com \
    /path/to/YOUR_REPLY

  https://kernel.org/pub/software/scm/git/docs/git-send-email.html

* If your mail client supports setting the In-Reply-To header
  via mailto: links, try the mailto: link
Be sure your reply has a Subject: header at the top and a blank line before the message body.
This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox

all inboxes | Powered by JetHome®