Re: [Intel-wired-lan] [PATCH v2] e1000e: free IRQ regardless of __E1000_DOWN

From: Baicar, Tyler
Date: Tue Nov 15 2016 - 16:50:15 EST

Next message: John Stultz: "Re: [RFC][PATCH 0/3] DWC2 fixes and hacks to make things work on HiKey"
Previous message: Steven Rostedt: "Re: [PATCH 1/2] trace-cmd: Makefile - link all trace-* objects into ctracecmd.so"
In reply to: Neftin, Sasha: "Re: [Intel-wired-lan] [PATCH v2] e1000e: free IRQ regardless of __E1000_DOWN"
Messages sorted by: [ date ] [ thread ] [ subject ] [ author ]

On 11/13/2016 2:25 AM, Neftin, Sasha wrote:

On 11/13/2016 10:34 AM, Neftin, Sasha wrote:

On 11/11/2016 12:35 AM, Baicar, Tyler wrote:

Hello Sasha,

On 11/9/2016 11:19 PM, Neftin, Sasha wrote:

On 11/9/2016 11:41 PM, Tyler Baicar wrote:

Move IRQ free code so that it will happen regardless of the
__E1000_DOWN bit. Currently the e1000e driver only releases its IRQ
if the __E1000_DOWN bit is cleared. This is not sufficient because
it is possible for __E1000_DOWN to be set without releasing the IRQ.
In such a situation, we will hit a kernel bug later in e1000_remove
because the IRQ still has action since it was never freed. A
secondary bus reset can cause this case to happen.

Signed-off-by: Tyler Baicar <tbaicar@xxxxxxxxxxxxxx>
---
drivers/net/ethernet/intel/e1000e/netdev.c | 3 ++-
1 file changed, 2 insertions(+), 1 deletion(-)

diff --git a/drivers/net/ethernet/intel/e1000e/netdev.c
b/drivers/net/ethernet/intel/e1000e/netdev.c
index 7017281..36cfcb0 100644
--- a/drivers/net/ethernet/intel/e1000e/netdev.c
+++ b/drivers/net/ethernet/intel/e1000e/netdev.c
@@ -4679,12 +4679,13 @@ int e1000e_close(struct net_device *netdev)
if (!test_bit(__E1000_DOWN, &adapter->state)) {
e1000e_down(adapter, true);
- e1000_free_irq(adapter);
/* Link status message must follow this format */
pr_info("%s NIC Link is Down\n", adapter->netdev->name);
}
+ e1000_free_irq(adapter);
+
napi_disable(&adapter->napi);
e1000e_free_tx_resources(adapter->tx_ring);

I would like not recommend insert this change. This change related
driver state machine, we afraid from lot of synchronization problem and
issues.
We need keep e1000_free_irq in loop and check for 'test_bit' ready.

What do you mean here? There is no loop. If __E1000_DOWN is set then we
will never free the IRQ.

Another point, does before execute secondary bus reset your SW back up
pcie configuration space as properly?

After a secondary bus reset, the link needs to recover and go back to a
working state after 1 second.

From the callstack, the issue is happening while removing the endpoint
from the system, before applying the secondary bus reset.

The order of events is
1. remove the drivers
2. cause a secondary bus reset
3. wait 1 second

Actually, this is too much, usually link up in less than 100ms.You can
check Data Link Layer indication.

4. recover the link

callstack:
free_msi_irqs+0x6c/0x1a8
pci_disable_msi+0xb0/0x148
e1000e_reset_interrupt_capability+0x60/0x78
e1000_remove+0xc8/0x180
pci_device_remove+0x48/0x118
__device_release_driver+0x80/0x108
device_release_driver+0x2c/0x40
pci_stop_bus_device+0xa0/0xb0
pci_stop_bus_device+0x3c/0xb0
pci_stop_root_bus+0x54/0x80
acpi_pci_root_remove+0x28/0x64
acpi_bus_trim+0x6c/0xa4
acpi_device_hotplug+0x19c/0x3f4
acpi_hotplug_work_fn+0x28/0x3c
process_one_work+0x150/0x460
worker_thread+0x50/0x4b8
kthread+0xd4/0xe8
ret_from_fork+0x10/0x50

Thanks,
Tyler

Hello Tyler,
Okay, we need consult more about this suggestion.
May I ask what is setup you run? Is there NIC or on board LAN? I would
like try reproduce this issue in our lab's too.
Also, is same issue observed with same scenario and others NIC's too?
Sasha
_______________________________________________
Intel-wired-lan mailing list
Intel-wired-lan@xxxxxxxxxxxxxxxx
http://lists.osuosl.org/mailman/listinfo/intel-wired-lan

Please, specify what is device used.

Hello Sasha,
This was on a QDF2432 using an Intel PRO/1000 PT Dual Port server adapter. I have not tried
other e1000e PCIe cards, but have not seen any similar issues with Mellanox cards. I'm able to
reproduce it with just pulling the card out. Here is the lspci -vvv output for this card:

0004:00:00.0 PCI bridge: Airgo Networks, Inc. Device 0400 (prog-if 00 [Normal decode])
Physical Slot: 5
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
Interrupt: pin A routed to IRQ 297
Bus: primary=00, secondary=01, subordinate=01, sec-latency=0
I/O behind bridge: 00002000-00002fff
Memory behind bridge: 00100000-002fffff
Prefetchable memory behind bridge: 00000c0400000000-00000c04001fffff
Secondary status: 66MHz- FastB2B- ParErr- DEVSEL=fast >TAbort- <TAbort- <MAbort- <SERR- <PERR-
BridgeCtl: Parity- SERR+ NoISA- VGA- MAbort- >Reset- FastB2B-
PriDiscTmr- SecDiscTmr- DiscTmrStat- DiscTmrSERREn-
Capabilities: [40] Power Management version 3
Flags: PMEClk- DSI- D1- D2- AuxCurrent=0mA 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: 00000000397f0040 Data: 0000
Capabilities: [70] Express (v2) Root Port (Slot+), MSI 00
DevCap: MaxPayload 512 bytes, PhantFunc 0
ExtTag- RBE+
DevCtl: Report errors: Correctable+ Non-Fatal+ Fatal+ Unsupported+
RlxdOrd+ ExtTag- PhantFunc- AuxPwr- NoSnoop+
MaxPayload 256 bytes, MaxReadReq 512 bytes
DevSta: CorrErr- UncorrErr- FatalErr- UnsuppReq- AuxPwr- TransPend-
LnkCap: Port #0, Speed 5GT/s, Width x8, ASPM L0s L1, Exit Latency L0s <1us, L1 <16us
ClockPM- Surprise- LLActRep+ BwNot+ ASPMOptComp+
LnkCtl: ASPM Disabled; RCB 128 bytes Disabled- CommClk-
ExtSynch- ClockPM- AutWidDis- BWInt- AutBWInt-
LnkSta: Speed 2.5GT/s, Width x4, TrErr- Train- SlotClk+ DLActive+ BWMgmt- ABWMgmt-
SltCap: AttnBtn+ PwrCtrl+ MRL+ AttnInd+ PwrInd+ HotPlug+ Surprise+
Slot #5, PowerLimit 75.000W; Interlock+ NoCompl-
SltCtl: Enable: AttnBtn- PwrFlt- MRL- PresDet- CmdCplt- HPIrq- LinkChg-
Control: AttnInd Off, PwrInd Off, Power- Interlock-
SltSta: Status: AttnBtn- PowerFlt- MRL- CmdCplt- PresDet- Interlock-
Changed: MRL- PresDet- LinkState-
RootCtl: ErrCorrectable- ErrNon-Fatal- ErrFatal- PMEIntEna+ CRSVisible-
RootCap: CRSVisible-
RootSta: PME ReqID 0000, PMEStatus- PMEPending-
DevCap2: Completion Timeout: Range ABCD, TimeoutDis+, LTR+, OBFF Not Supported ARIFwd+
DevCtl2: Completion Timeout: 50us to 50ms, TimeoutDis-, LTR-, OBFF Disabled ARIFwd-
LnkCtl2: Target Link Speed: 5GT/s, EnterCompliance- SpeedDis-
Transmit Margin: Normal Operating Range, EnterModifiedCompliance- ComplianceSOS-
Compliance De-emphasis: -6dB
LnkSta2: Current De-emphasis Level: -3.5dB, EqualizationComplete-, EqualizationPhase1-
EqualizationPhase2-, EqualizationPhase3-, LinkEqualizationRequest-
Capabilities: [100 v2] 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: [178 v1] #19
Kernel driver in use: pcieport

0004:01:00.0 Ethernet controller: Intel Corporation 82571EB Gigabit Ethernet Controller (rev 06)
Subsystem: Intel Corporation PRO/1000 PT Dual Port Server Adapter
Physical Slot: 5-1
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: 128 bytes
Interrupt: pin A routed to IRQ 299
Region 0: Memory at c0100100000 (32-bit, non-prefetchable) [size=128K]
Region 1: Memory at c0100120000 (32-bit, non-prefetchable) [size=128K]
Region 2: I/O ports at 1000 [size=32]
Expansion ROM at c0100140000 [disabled] [size=128K]
Capabilities: [c8] 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=1 PME-
Capabilities: [d0] MSI: Enable+ Count=1/1 Maskable- 64bit+
Address: 00000000397f0040 Data: 0000
Capabilities: [e0] Express (v1) Endpoint, MSI 00
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 256 bytes, MaxReadReq 512 bytes
DevSta: CorrErr- UncorrErr- FatalErr- UnsuppReq- AuxPwr+ TransPend-
LnkCap: Port #8, Speed 2.5GT/s, Width x4, ASPM L0s, Exit Latency L0s <4us, L1 <64us
ClockPM- Surprise- LLActRep- BwNot- ASPMOptComp-
LnkCtl: ASPM Disabled; RCB 64 bytes Disabled- CommClk-
ExtSynch- ClockPM- AutWidDis- BWInt- AutBWInt-
LnkSta: Speed 2.5GT/s, Width x4, TrErr- Train- SlotClk+ DLActive- BWMgmt- ABWMgmt-
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: [140 v1] Device Serial Number 68-05-ca-ff-ff-3e-5b-7a
Kernel driver in use: e1000e

0004:01:00.1 Ethernet controller: Intel Corporation 82571EB Gigabit Ethernet Controller (rev 06)
Subsystem: Intel Corporation PRO/1000 PT Dual Port Server Adapter
Physical Slot: 5-1
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: 128 bytes
Interrupt: pin B routed to IRQ 301
Region 0: Memory at c0100160000 (32-bit, non-prefetchable) [size=128K]
Region 1: Memory at c0100180000 (32-bit, non-prefetchable) [size=128K]
Region 2: I/O ports at 1020 [size=32]
Expansion ROM at c01001a0000 [disabled] [size=128K]
Capabilities: [c8] 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=1 PME-
Capabilities: [d0] MSI: Enable+ Count=1/1 Maskable- 64bit+
Address: 00000000397f0040 Data: 0000
Capabilities: [e0] Express (v1) Endpoint, MSI 00
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 256 bytes, MaxReadReq 512 bytes
DevSta: CorrErr- UncorrErr- FatalErr- UnsuppReq- AuxPwr+ TransPend-
LnkCap: Port #8, Speed 2.5GT/s, Width x4, ASPM L0s, Exit Latency L0s <4us, L1 <64us
ClockPM- Surprise- LLActRep- BwNot- ASPMOptComp-
LnkCtl: ASPM Disabled; RCB 64 bytes Disabled- CommClk-
ExtSynch- ClockPM- AutWidDis- BWInt- AutBWInt-
LnkSta: Speed 2.5GT/s, Width x4, TrErr- Train- SlotClk+ DLActive- BWMgmt- ABWMgmt-
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: [140 v1] Device Serial Number 68-05-ca-ff-ff-3e-5b-7a
Kernel driver in use: e1000e

Thanks,
Tyler

--
Qualcomm Datacenter Technologies, Inc. as an affiliate of Qualcomm Technologies, Inc.
Qualcomm Technologies, Inc. is a member of the Code Aurora Forum,
a Linux Foundation Collaborative Project.

Next message: John Stultz: "Re: [RFC][PATCH 0/3] DWC2 fixes and hacks to make things work on HiKey"
Previous message: Steven Rostedt: "Re: [PATCH 1/2] trace-cmd: Makefile - link all trace-* objects into ctracecmd.so"
In reply to: Neftin, Sasha: "Re: [Intel-wired-lan] [PATCH v2] e1000e: free IRQ regardless of __E1000_DOWN"
Messages sorted by: [ date ] [ thread ] [ subject ] [ author ]