For the netdev list

For the netdev list

[Tom Goetz]

[-- Attachment #1: Type: text/plain, Size: 569 bytes --]

We recently obtained a new a Lenovo Edge 0578-CTO. The r8169 driver causes instability in the system on this machine. The problem is that in rtl8169_rx_interrupt (status & 0x00001FFF) returns values less than four on this machine. This results in this line:

int pkt_size = (status & 0x00001FFF) - 4;

giving a huge packet size which causes problem when the packet is copied. For a work around we've added a patch to drop packets when we see this condition. I have attached lspci -vvv for this device and a patch for the work around we're using.

-Tom Goetz



[-- Attachment #2: r8168_lspci.log --]
[-- Type: application/octet-stream, Size: 3293 bytes --]

09:00.0 Ethernet controller: Realtek Semiconductor Co., Ltd. RTL8111/8168B PCI Express Gigabit Ethernet controller (rev 03)
	Subsystem: Lenovo Device 2131
	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 299
	Region 0: I/O ports at 4000 [size=256]
	Region 2: Memory at f0904000 (64-bit, prefetchable) [size=4K]
	Region 4: Memory at f0900000 (64-bit, prefetchable) [size=16K]
	[virtual] Expansion ROM at f0920000 [disabled] [size=128K]
	Capabilities: [40] Power Management version 3
		Flags: PMEClk- DSI- D1+ D2+ AuxCurrent=375mA PME(D0+,D1+,D2+,D3hot+,D3cold+)
		Status: D0 NoSoftRst+ PME-Enable- DSel=0 DScale=0 PME-
	Capabilities: [50] MSI: Enable+ Count=1/1 Maskable- 64bit+
		Address: 00000000fee0200c  Data: 41c8
	Capabilities: [70] Express (v2) Endpoint, MSI 01
		DevCap:	MaxPayload 256 bytes, PhantFunc 0, Latency L0s <512ns, L1 <64us
			ExtTag- AttnBtn- AttnInd- PwrInd- RBE+ FLReset-
		DevCtl:	Report errors: Correctable- Non-Fatal- Fatal- Unsupported-
			RlxdOrd+ ExtTag- PhantFunc- AuxPwr- NoSnoop-
			MaxPayload 128 bytes, MaxReadReq 4096 bytes
		DevSta:	CorrErr- UncorrErr- FatalErr- UnsuppReq- AuxPwr+ TransPend-
		LnkCap:	Port #0, Speed 2.5GT/s, Width x1, ASPM L0s L1, Latency L0 <512ns, L1 <64us
			ClockPM+ Surprise- LLActRep- BwNot-
		LnkCtl:	ASPM L1 Enabled; RCB 64 bytes Disabled- Retrain- CommClk+
			ExtSynch- ClockPM- AutWidDis- BWInt- AutBWInt-
		LnkSta:	Speed 2.5GT/s, Width x1, TrErr- Train- SlotClk+ DLActive- BWMgmt- ABWMgmt-
		DevCap2: Completion Timeout: Not Supported, TimeoutDis+
		DevCtl2: Completion Timeout: 50us to 50ms, TimeoutDis-
		LnkCtl2: Target Link Speed: 2.5GT/s, EnterCompliance- SpeedDis-, Selectable De-emphasis: -6dB
			 Transmit Margin: Normal Operating Range, EnterModifiedCompliance- ComplianceSOS-
			 Compliance De-emphasis: -6dB
		LnkSta2: Current De-emphasis Level: -6dB
	Capabilities: [ac] MSI-X: Enable- Count=4 Masked-
		Vector table: BAR=4 offset=00000000
		PBA: BAR=4 offset=00000800
	Capabilities: [cc] Vital Product Data
		Unknown small resource type 00, 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: 00, GenCap+ CGenEn- ChkCap+ ChkEn-
	Capabilities: [140 v1] Virtual Channel
		Caps:	LPEVC=0 RefClk=100ns PATEntryBits=1
		Arb:	Fixed- WRR32- WRR64- WRR128-
		Ctrl:	ArbSelect=Fixed
		Status:	InProgress-
		VC0:	Caps:	PATOffset=00 MaxTimeSlots=1 RejSnoopTrans-
			Arb:	Fixed- WRR32- WRR64- WRR128- TWRR128- WRR256-
			Ctrl:	Enable+ ID=0 ArbSelect=Fixed TC/VC=ff
			Status:	NegoPending- InProgress-
	Capabilities: [160 v1] Device Serial Number d4-00-00-00-68-4c-e0-00
	Kernel driver in use: r8169
	Kernel modules: r8169


[-- Attachment #3: rtl8169.patch --]
[-- Type: application/octet-stream, Size: 652 bytes --]

diff --git a/drivers/net/r8169.c b/drivers/net/r8169.c
index 7ffdb80..4c8ad2a 100644
--- a/drivers/net/r8169.c
+++ b/drivers/net/r8169.c
@@ -4579,6 +4579,14 @@ static int rtl8169_rx_interrupt(struct net_device *dev,
 			dma_addr_t addr = le64_to_cpu(desc->addr);
 			int pkt_size = (status & 0x00001FFF) - 4;
 
+			if ((status & 0x00001FFF) < 4) {
+				dev->stats.rx_dropped++;
+				dev->stats.rx_length_errors++;
+				rtl8169_mark_to_asic(desc, rx_buf_sz);
+				printk("%s: bad packet length!\n", __FUNCTION__);
+				continue;
+			}
+
 			/*
 			 * The driver does not support incoming fragmented
 			 * frames. They are seen as a symptom of over-mtu

Re: For the netdev list

[Francois Romieu]

Tom Goetz <tom.goetz@virtualcomputer.com> :
> We recently obtained a new a Lenovo Edge 0578-CTO. The r8169 driver causes
> instability in the system on this machine. The problem is that in
> rtl8169_rx_interrupt (status & 0x00001FFF) returns values less than four

This is unexpected. :o(

[...]
> For a work around we've added a patch to drop packets when we see this
> condition. I have attached lspci -vvv for this device and a patch for the
> work around we're using.

Thank you for debugging.

Can you grep for the XID of the device in the kernel's dmesg and specify
a bit of context for the problem (MTU ? features enabled through ethtool ?
kernel version ?) ?

-- 
Ueimor

Re: For the netdev list

[Tom Goetz]

On May 7, 2011, at 2:26 PM, Francois Romieu wrote:

> Tom Goetz <tom.goetz@virtualcomputer.com> :
>> We recently obtained a new a Lenovo Edge 0578-CTO. The r8169 driver causes
>> instability in the system on this machine. The problem is that in
>> rtl8169_rx_interrupt (status & 0x00001FFF) returns values less than four
> 
> This is unexpected. :o(
> 
> [...]
>> For a work around we've added a patch to drop packets when we see this
>> condition. I have attached lspci -vvv for this device and a patch for the
>> work around we're using.
> 
> Thank you for debugging.
> 
> Can you grep for the XID of the device in the kernel's dmesg and specify
> a bit of context for the problem (MTU ? features enabled through ethtool ?
> kernel version ?) ?

This is 2.6.38 PVOPs Dom0 on Xen. The distro is Ubuntu 11.04. We have not had issues with this driver in the past. This is a new issue with the Lenovo Edge.

Here's a log fragment with the XID and output from ifconfig and ethtool:

[    3.197341] r8169 Gigabit Ethernet driver 2.3LK-NAPI loaded
[    3.197387] xen: registering gsi 17 triggering 0 polarity 1
[    3.197394] xen_map_pirq_gsi: returning irq 17 for gsi 17
[    3.197397] xen: --> irq=17
[    3.197406] Already setup the GSI :17
[    3.197412] r8169 0000:09:00.0: PCI INT A -> GSI 17 (level, low) -> IRQ 17
[    3.197524] r8169 0000:09:00.0: setting latency timer to 64
[    3.197990] r8169 0000:09:00.0: eth0: RTL8168d/8111d at 0xffffc9001117c000, e8:9a:8f:0c:6c:62, XID 083000c0 IRQ 299

eth0      Link encap:Ethernet  HWaddr e8:9a:8f:0c:6c:62  
          UP BROADCAST RUNNING MULTICAST  MTU:1500  Metric:1
          RX packets:1138 errors:0 dropped:0 overruns:0 frame:0
          TX packets:284 errors:0 dropped:0 overruns:0 carrier:0
          collisions:0 txqueuelen:1000 
          RX bytes:183700 (183.7 KB)  TX bytes:107686 (107.6 KB)
          Interrupt:43 Base address:0xc000 

root@edge-11-04:~# ethtool eth0
Settings for eth0:
	Supported ports: [ TP MII ]
	Supported link modes:   10baseT/Half 10baseT/Full 
	                        100baseT/Half 100baseT/Full 
	                        1000baseT/Half 1000baseT/Full 
	Supports auto-negotiation: Yes
	Advertised link modes:  10baseT/Half 10baseT/Full 
	                        100baseT/Half 100baseT/Full 
	                        1000baseT/Half 1000baseT/Full 
	Advertised pause frame use: No
	Advertised auto-negotiation: Yes
	Link partner advertised link modes:  10baseT/Half 10baseT/Full 
	                                     100baseT/Half 100baseT/Full 
	                                     1000baseT/Full 
	Link partner advertised pause frame use: No
	Link partner advertised auto-negotiation: Yes
	Speed: 1000Mb/s
	Duplex: Full
	Port: MII
	PHYAD: 0
	Transceiver: internal
	Auto-negotiation: on
	Supports Wake-on: pumbg
	Wake-on: g
	Current message level: 0x00000033 (51)
			       drv probe ifdown ifup
	Link detected: yes

-Tom