Re: [PATCH RFC] pci: Blacklist vpd access for buggy devices

From: Babu Moger
Date: Tue Jan 19 2016 - 15:39:25 EST

Hi Jordan,

On 1/19/2016 9:22 AM, Jordan_Hargrave@xxxxxxxx wrote:
> From: Babu Moger [babu.moger@xxxxxxxxxx]
> Sent: Monday, January 11, 2016 4:49 PM
> To: bhelgaas@xxxxxxxxxx
> Cc: linux-pci@xxxxxxxxxxxxxxx; linux-kernel@xxxxxxxxxxxxxxx; alexander.duyck@xxxxxxxxx; hare@xxxxxxx; mkubecek@xxxxxxxx; shane.seymour@xxxxxxx; myron.stowe@xxxxxxxxx; VenkatKumar.Duvvuru@xxxxxxxxx; Hargrave, Jordan
> Subject: Re: [PATCH RFC] pci: Blacklist vpd access for buggy devices
>
> Sorry. Missed Jordan.
>
> On 1/11/2016 3:13 PM, Babu Moger wrote:
>> Reading or Writing of PCI VPD data causes system panic.
>> We saw this problem by running "lspci -vvv" in the beginning.
>> However this can be easily reproduced by running
>> cat /sys/bus/devices/XX../vpd
>>
>> VPD length has been set as 32768 by default. Accessing vpd
>> will trigger read/write of 32k. This causes problem as we
>> could read data beyond the VPD end tag. Behaviour is un-
>> predictable when this happens. I see some other adapter doing
>> similar quirks(commit bffadffd43d4 ("PCI: fix VPD limit quirk
>> for Broadcom 5708S"))
>>
>> I see there is an attempt to fix this right way.
>> https://patchwork.ozlabs.org/patch/534843/ or
>> https://lkml.org/lkml/2015/10/23/97
>>
>> Tried to fix it this way, but problem is I dont see the proper
>> start/end TAGs(at least for this adapter) at all. The data is
>> mostly junk or zeros. This patch fixes the issue by setting the
>> vpd length to 0x80.
>>
>> Also look at the threds
>>
>> https://lkml.org/lkml/2015/11/10/557
>> https://lkml.org/lkml/2015/12/29/315
>>
>> Signed-off-by: Babu Moger <babu.moger@xxxxxxxxxx>
>> ---
>>
>> NOTE:
>> Jordan, Are you sure all the devices in PCI_VENDOR_ID_ATHEROS and
>> PCI_VENDOR_ID_ATTANSIC have this problem. You have used PCI_ANY_ID.
>> I felt it is too broad. Can you please check.
>>
>
> I don't actually have that hardware, it was a bugfix for biosdevname for RedHat. We were getting
> 'BUG: soft lockup - CPU#0 stuck for 23s!' when attempting to read the vpd area.
>
> Certainly 0x1969:0x1026 experienced this.

Ok. Thanks. I will update the patch 4/4.

>
> 09:00.0 Ethernet controller: Atheros Communications AR8121/AR8113/AR8114 Gigabit or Fast Ethernet (rev b0)
> Subsystem: Atheros Communications AR8121/AR8113/AR8114 Gigabit or Fast Ethernet
> Control: I/O+ Mem+ BusMaster+ SpecCycle- MemWINV- VGASnoop- ParErr- Stepping- SERR- FastB2B- DisINTx+
> Status: Cap+ 66MHz- UDF- FastB2B- ParErr- DEVSEL=fast >TAbort- <TAbort- <MAbort- >SERR- <PERR- INTx-
> Latency: 0, Cache Line Size: 64 bytes
> Interrupt: pin A routed to IRQ 46
> Region 0: Memory at c0300000 (64-bit, non-prefetchable) [size=256K]
> Region 2: I/O ports at 3000 [size=128]
> Capabilities: [40] Power Management version 2
> Flags: PMEClk- DSI- D1- D2- AuxCurrent=0mA PME(D0-,D1-,D2-,D3hot+,D3cold+)
> Status: D0 NoSoftRst- PME-Enable- DSel=0 DScale=0 PME-
> Capabilities: [48] MSI: Enable+ Count=1/1 Maskable- 64bit+
> Address: 00000000fee0300c Data: 41a1
> Capabilities: [58] Express (v1) Endpoint, MSI 00
> DevCap: MaxPayload 4096 bytes, PhantFunc 0, Latency L0s <4us, L1 unlimited
> ExtTag- AttnBtn+ AttnInd+ PwrInd+ RBE- FLReset-
> DevCtl: Report errors: Correctable- Non-Fatal- Fatal- Unsupported-
> RlxdOrd- ExtTag- PhantFunc- AuxPwr- NoSnoop-
> MaxPayload 128 bytes, MaxReadReq 512 bytes
> DevSta: CorrErr- UncorrErr+ FatalErr- UnsuppReq+ AuxPwr+ TransPend-
> LnkCap: Port #0, Speed 2.5GT/s, Width x1, ASPM L0s, Latency L0 unlimited, L1 unlimited
> ClockPM- Surprise- LLActRep- BwNot-
> LnkCtl: ASPM Disabled; RCB 64 bytes Disabled- Retrain- CommClk+
> ExtSynch- ClockPM- AutWidDis- BWInt- AutBWInt-
> LnkSta: Speed 2.5GT/s, Width x1, TrErr- Train- SlotClk+ DLActive- BWMgmt- ABWMgmt-
> Capabilities: [6c] Vital Product Data
> Unknown small resource type 0b, will not decode more.
> Capabilities: [100 v1] Advanced Error Reporting
> UESta: DLP- SDES- TLP- FCP- CmpltTO- CmpltAbrt- UnxCmplt- RxOF- MalfTLP- ECRC- UnsupReq+ ACSViol-
> UEMsk: DLP- SDES- TLP- FCP- CmpltTO- CmpltAbrt- UnxCmplt- RxOF- MalfTLP- ECRC- UnsupReq- ACSViol-
> UESvrt: DLP+ SDES- TLP- FCP+ CmpltTO- CmpltAbrt- UnxCmplt- RxOF+ MalfTLP+ ECRC- UnsupReq- ACSViol-
> CESta: RxErr- BadTLP- BadDLLP- Rollover- Timeout- NonFatalErr-
> CEMsk: RxErr- BadTLP- BadDLLP- Rollover- Timeout- NonFatalErr-
> AERCap: First Error Pointer: 14, GenCap+ CGenEn- ChkCap+ ChkEn-
> Capabilities: [180 v1] Device Serial Number ff-2e-05-c3-00-23-8b-ff
> Kernel driver in use: ATL1E
> 00: 69 19 26 10 07 04 10 00 b0 00 00 02 10 00 00 00
> 10: 04 00 30 c0 00 00 00 00 01 30 00 00 00 00 00 00
> 20: 00 00 00 00 00 00 00 00 00 00 00 00 69 19 26 10
> 30: 00 00 00 00 40 00 00 00 00 00 00 00 0a 01 00 00
> 40: 01 48 02 c0 00 00 00 00 05 58 81 00 0c 30 e0 fe
> 50: 00 00 00 00 a1 41 00 00 10 6c 01 00 85 7f 04 05
> 60: 00 20 1a 00 11 f4 03 00 40 00 11 10 03 00 00 80
> 70: 5a ff 88 14 00 00 00 00 00 00 00 00 00 00 00 00
> 80: 00 00 00 00 69 19 26 10 00 00 00 00 00 00 00 00
> 90: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
> a0: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
> b0: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
> c0: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
> d0: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
> e0: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
> f0: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
>
>> drivers/pci/quirks.c | 41 +++++++++++++++++++++++++++++++++++++++++
>> 1 files changed, 41 insertions(+), 0 deletions(-)
>>
>> diff --git a/drivers/pci/quirks.c b/drivers/pci/quirks.c
>> index b03373f..8abcee5 100644
>> --- a/drivers/pci/quirks.c
>> +++ b/drivers/pci/quirks.c
>> @@ -2123,6 +2123,47 @@ static void quirk_via_cx700_pci_parking_caching(struct pci_dev *dev)
>> DECLARE_PCI_FIXUP_FINAL(PCI_VENDOR_ID_VIA, 0x324e, quirk_via_cx700_pci_parking_caching);
>>
>> /*
>> + * A read/write to sysfs entry ('/sys/bus/pci/devices/<id>/vpd')
>> + * will dump 32k of data. The default length is set as 32768.
>> + * Reading a full 32k will cause an access beyond the VPD end tag.
>> + * The system behaviour at that point is mostly unpredictable.
>> + * Apparently, some vendors have not implemented this VPD headers properly.
>> + * Adding a generic function disable vpd data for these buggy adapters
>> + * Add the DECLARE_PCI_FIXUP_FINAL line below with the specific with
>> + * vendor and device of interest to use this quirk.
>> + */
>> +static void quirk_blacklist_vpd(struct pci_dev *dev)
>> +{
>> + if (dev->vpd) {
>> + dev->vpd->len = 0;
>> + dev_warn(&dev->dev, "PCI vpd access has been disabled due to firmware bug\n");
>> + }
>> +}
>> +
>> +DECLARE_PCI_FIXUP_FINAL(PCI_VENDOR_ID_LSI_LOGIC, 0x0060,
>> + quirk_blacklist_vpd);
>> +DECLARE_PCI_FIXUP_FINAL(PCI_VENDOR_ID_LSI_LOGIC, 0x007c,
>> + quirk_blacklist_vpd);
>> +DECLARE_PCI_FIXUP_FINAL(PCI_VENDOR_ID_LSI_LOGIC, 0x0413,
>> + quirk_blacklist_vpd);
>> +DECLARE_PCI_FIXUP_FINAL(PCI_VENDOR_ID_LSI_LOGIC, 0x0078,
>> + quirk_blacklist_vpd);
>> +DECLARE_PCI_FIXUP_FINAL(PCI_VENDOR_ID_LSI_LOGIC, 0x0079,
>> + quirk_blacklist_vpd);
>> +DECLARE_PCI_FIXUP_FINAL(PCI_VENDOR_ID_LSI_LOGIC, 0x0073,
>> + quirk_blacklist_vpd);
>> +DECLARE_PCI_FIXUP_FINAL(PCI_VENDOR_ID_LSI_LOGIC, 0x0071,
>> + quirk_blacklist_vpd);
>> +DECLARE_PCI_FIXUP_FINAL(PCI_VENDOR_ID_LSI_LOGIC, 0x005b,
>> + quirk_blacklist_vpd);
>> +DECLARE_PCI_FIXUP_FINAL(PCI_VENDOR_ID_LSI_LOGIC, 0x002f,
>> + quirk_blacklist_vpd);
>> +DECLARE_PCI_FIXUP_FINAL(PCI_VENDOR_ID_LSI_LOGIC, 0x005d,
>> + quirk_blacklist_vpd);
>> +DECLARE_PCI_FIXUP_FINAL(PCI_VENDOR_ID_LSI_LOGIC, 0x005f,
>> + quirk_blacklist_vpd);
>> +
>> +/*
>> * For Broadcom 5706, 5708, 5709 rev. A nics, any read beyond the
>> * VPD end tag will hang the device. This problem was initially
>> * observed when a vpd entry was created in sysfs
>>