The same issue has been posted here: http://lists.freedesktop.org/archives/intel-gfx/2011-May/010813.html

In both cases this is in conjunction with i915 graphics. Looks also similar to this report:
http://marc.info/?l=linux-i2c&m=130331955203194&w=2
So I think there's something wrong in the i915 video driver.

Please boot with i915.modeset=0 and see if it helps.

I don't think there's any bug in the eeprom driver itself. As a matter of fact, the eeprom driver is exactly the same in kernels 2.6.38 and 2.6.39. But the eeprom driver probes many I2C buses, including the ones hanging off the video chip. The hang must happen at that time.

You should be able to reproduce the hang by loading the i2c-dev driver, installing i2c-tools, and calling i2cdetect on the i915 I2C buses. This would rule out any problem with the eeprom driver.

If anyone can bisect the kernel tree to find out the faulty commit, that would help too.

(switched to email.  Please respond via emailed reply-to-all, not via the
bugzilla web interface).

On Sat, 21 May 2011 20:17:32 GMT
bugzilla-daemon@bugzilla.kernel.org wrote:

> https://bugzilla.kernel.org/show_bug.cgi?id=35572
> 
>            Summary: eeprom module: modprobing hangs
>            Product: Other
>            Version: 2.5
>     Kernel Version: 2.6.39
>           Platform: All
>         OS/Version: Linux
>               Tree: Mainline
>             Status: NEW
>           Severity: normal
>           Priority: P1
>          Component: Modules
>         AssignedTo: other_modules@kernel-bugs.osdl.org
>         ReportedBy: markotahal@gmail.com
>         Regression: No

This is drivers/misc/eeprom/eeprom.c?

That driver doesn't really have a maintainer.  Perhaps the i2c
developers can help debug this?

> 
> modbrobing eeprom module hangs, but does not crash the kernel. Occurs with
> 2.6.39, with 2.6.38 and prev works ok.

So 2.6.38 did not have this bug?

The driver didn't change between .38 and .39.

> Confirmed by other user, the bug
> reported in Arch can be found here: 
> https://bugs.archlinux.org/24376
> 
> my HW: 
> i686, archlinux kernel (no relevant patch, almost same as mainline :
> ftp://ftp.archlinux.org/other/kernel26/patch-2.6.39-1-ARCH.bz2 ), 
> 
> 
> part from dmesg when modprobing eeprom:
>  57.222509] tg3 0000:02:00.0: eth0: Flow control is on for TX and on for RX
> [   57.223449] ADDRCONF(NETDEV_CHANGE): eth0: link becomes ready
> [   67.936739] eth0: no IPv6 routers present
> [   93.797133] ip_tables: (C) 2000-2006 Netfilter Core Team
> [   94.057661] nf_conntrack version 0.5.0 (16384 buckets, 65536 max)
> [  106.272909] EXT4-fs (sda4): re-mounted. Opts: commit=0
> [  106.957966] EXT4-fs (sda9): re-mounted. Opts: commit=0
> [  107.181605] EXT4-fs (sda2): re-mounted. Opts: commit=0
> [  107.331670] EXT4-fs (sda12): re-mounted. Opts: commit=0
> [  136.933416] [drm] GMBUS timed out, falling back to bit banging on pin 0
> [i915 gmbus disabled]
> [  136.986739] [drm] GMBUS timed out, falling back to bit banging on pin 0
> [i915 gmbus disabled]
> [  137.043440] [drm] GMBUS timed out, falling back to bit banging on pin 0
> [i915 gmbus disabled]
> [  137.096738] [drm] GMBUS timed out, falling back to bit banging on pin 0
> [i915 gmbus disabled]
> [  137.150067] [drm] GMBUS timed out, falling back to bit banging on pin 0
> [i915 gmbus disabled]
> [  137.203415] [drm] GMBUS timed out, falling back to bit banging on pin 0
> [i915 gmbus disabled]
> [  137.256761] [drm] GMBUS timed out, falling back to bit banging on pin 0
> [i915 gmbus disabled]
> [  137.310101] [drm] GMBUS timed out, falling back to bit banging on pin 0
> [i915 gmbus disabled]
> [  137.523400] [drm] GMBUS timed out, falling back to bit banging on pin 4
> [i915 gmbus dpc]
> [  178.299024] kwin_opengl_tes[3439]: segfault at 2c ip b70a5c48 sp bfb90520
> error 4 in i915_dri.so[b706c000+35b000]
> [  213.183783] process `skype' is using obsolete setsockopt SO_BSDCOMPAT
> 
> 
> 
> 
> lspci -vvv
> 00:00.0 Host bridge: Intel Corporation Mobile 945GME Express Memory
> Controller
> Hub (rev 03)
>         Subsystem: Lenovo Device 386f
>         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
>         Capabilities: [e0] Vendor Specific Information: Len=09 <?>
>         Kernel driver in use: agpgart-intel
>         Kernel modules: intel-agp
> 
> 00:02.0 VGA compatible controller: Intel Corporation Mobile 945GME Express
> Integrated Graphics Controller (rev 03) (prog-if 00 [VGA controller])
>         Subsystem: Lenovo Device 3870
>         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 16
>         Region 0: Memory at f0300000 (32-bit, non-prefetchable) [size=512K]
>         Region 1: I/O ports at 1800 [size=8]
>         Region 2: Memory at d0000000 (32-bit, prefetchable) [size=256M]
>         Region 3: Memory at f0400000 (32-bit, non-prefetchable) [size=256K]
>         Expansion ROM at <unassigned> [disabled]
>         Capabilities: [90] MSI: Enable- Count=1/1 Maskable- 64bit-
>                 Address: 00000000  Data: 0000
>         Capabilities: [d0] 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-
>         Kernel driver in use: i915
>         Kernel modules: i915
> 
> 00:02.1 Display controller: Intel Corporation Mobile 945GM/GMS/GME,
> 943/940GML
> Express Integrated Graphics Controller (rev 03)
>         Subsystem: Lenovo Device 3870
>         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
>         Region 0: Memory at f0380000 (32-bit, non-prefetchable) [size=512K]
>         Capabilities: [d0] 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-
> 
> 00:1b.0 Audio device: Intel Corporation N10/ICH 7 Family High Definition
> Audio
> Controller (rev 02)
>         Subsystem: Lenovo Device 3bf8
>         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 43
>         Region 0: Memory at f0440000 (64-bit, non-prefetchable) [size=16K]
>         Capabilities: [50] Power Management version 2
>                 Flags: PMEClk- DSI- D1- D2- AuxCurrent=55mA
> PME(D0+,D1-,D2-,D3hot+,D3cold+)
>                 Status: D0 NoSoftRst- PME-Enable- DSel=0 DScale=0 PME-
>         Capabilities: [60] MSI: Enable+ Count=1/1 Maskable- 64bit+
>                 Address: 00000000fee0300c  Data: 4179
>         Capabilities: [70] Express (v1) Root Complex Integrated Endpoint, MSI
> 00
>                 DevCap: MaxPayload 128 bytes, PhantFunc 0, Latency L0s <64ns,
> L1 <1us
>                         ExtTag- RBE- FLReset-
>                 DevCtl: Report errors: Correctable- Non-Fatal- Fatal-
> Unsupported-
>                         RlxdOrd- ExtTag- PhantFunc- AuxPwr- NoSnoop+
>                         MaxPayload 128 bytes, MaxReadReq 128 bytes
>                 DevSta: CorrErr- UncorrErr- FatalErr- UnsuppReq- AuxPwr+
> TransPend-
>                 LnkCap: Port #0, Speed unknown, Width x0, ASPM unknown,
>                 Latency
> L0 <64ns, L1 <1us
>                         ClockPM- Surprise- LLActRep- BwNot-
>                 LnkCtl: ASPM Disabled; Disabled- Retrain- CommClk-
>                         ExtSynch- ClockPM- AutWidDis- BWInt- AutBWInt-
>                 LnkSta: Speed unknown, Width x0, TrErr- Train- SlotClk-
> DLActive- BWMgmt- ABWMgmt-
>         Capabilities: [100 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=01
>                         Status: NegoPending- InProgress-
>                 VC1:    Caps:   PATOffset=00 MaxTimeSlots=1 RejSnoopTrans-
>                         Arb:    Fixed- WRR32- WRR64- WRR128- TWRR128- WRR256-
>                         Ctrl:   Enable+ ID=1 ArbSelect=Fixed TC/VC=80
>                         Status: NegoPending- InProgress-
>         Capabilities: [130 v1] Root Complex Link
>                 Desc:   PortNumber=0f ComponentID=02 EltType=Config
>                 Link0:  Desc:   TargetPort=00 TargetComponent=02 AssocRCRB-
> LinkType=MemMapped LinkValid+
>                         Addr:   00000000fed1c000
>         Kernel driver in use: HDA Intel
>         Kernel modules: snd-hda-intel
> 
> 00:1c.0 PCI bridge: Intel Corporation N10/ICH 7 Family PCI Express Port 1
> (rev
> 02) (prog-if 00 [Normal decode])
>         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
>         Bus: primary=00, secondary=02, subordinate=02, sec-latency=0
>         I/O behind bridge: 00002000-00002fff
>         Memory behind bridge: f0100000-f01fffff
>         Prefetchable memory behind bridge: 00000000f0000000-00000000f00fffff
>         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] Express (v1) Root Port (Slot+), MSI 00
>                 DevCap: MaxPayload 128 bytes, PhantFunc 0, Latency L0s
> unlimited, L1 unlimited
>                         ExtTag- RBE- FLReset-
>                 DevCtl: Report errors: Correctable- Non-Fatal- Fatal-
> Unsupported-
>                         RlxdOrd- ExtTag- PhantFunc- AuxPwr- NoSnoop-
>                         MaxPayload 128 bytes, MaxReadReq 128 bytes
>                 DevSta: CorrErr+ UncorrErr- FatalErr- UnsuppReq- AuxPwr+
> TransPend-
>                 LnkCap: Port #1, Speed 2.5GT/s, Width x1, ASPM L0s L1,
>                 Latency
> L0 <256ns, L1 <4us
>                         ClockPM- Surprise- LLActRep+ BwNot-
>                 LnkCtl: ASPM L0s 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-
>                 SltCap: AttnBtn- PwrCtrl- MRL- AttnInd- PwrInd- HotPlug+
> Surprise+
>                         Slot #2, PowerLimit 6.500W; Interlock- NoCompl-
>                 SltCtl: Enable: AttnBtn- PwrFlt- MRL- PresDet+ CmdCplt-
>                 HPIrq-
> LinkChg-
>                         Control: AttnInd Unknown, PwrInd Unknown, 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-
>         Capabilities: [80] MSI: Enable+ Count=1/1 Maskable- 64bit-
>                 Address: fee0300c  Data: 4151
>         Capabilities: [90] Subsystem: Intel Corporation Device 1999
>         Capabilities: [a0] 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: [100 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=01
>                         Status: NegoPending- InProgress-
>                 VC1:    Caps:   PATOffset=00 MaxTimeSlots=1 RejSnoopTrans-
>                         Arb:    Fixed+ WRR32- WRR64- WRR128- TWRR128- WRR256-
>                         Ctrl:   Enable- ID=0 ArbSelect=Fixed TC/VC=00
>                         Status: NegoPending- InProgress-
>         Capabilities: [180 v1] Root Complex Link
>                 Desc:   PortNumber=01 ComponentID=02 EltType=Config
>                 Link0:  Desc:   TargetPort=00 TargetComponent=02 AssocRCRB-
> LinkType=MemMapped LinkValid+
>                         Addr:   00000000fed1c001
>         Kernel driver in use: pcieport
>         Kernel modules: shpchp
> 
> 00:1c.1 PCI bridge: Intel Corporation N10/ICH 7 Family PCI Express Port 2
> (rev
> 02) (prog-if 00 [Normal decode])
>         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
>         Bus: primary=00, secondary=03, subordinate=03, sec-latency=0
>         I/O behind bridge: 00004000-00004fff
>         Memory behind bridge: 80200000-803fffff
>         Prefetchable memory behind bridge: 0000000080400000-00000000805fffff
>         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] Express (v1) Root Port (Slot+), MSI 00
>                 DevCap: MaxPayload 128 bytes, PhantFunc 0, Latency L0s
> unlimited, L1 unlimited
>                         ExtTag- RBE- FLReset-
>                 DevCtl: Report errors: Correctable- Non-Fatal- Fatal-
> Unsupported-
>                         RlxdOrd- ExtTag- PhantFunc- AuxPwr- NoSnoop-
>                         MaxPayload 128 bytes, MaxReadReq 128 bytes
>                 DevSta: CorrErr- UncorrErr- FatalErr- UnsuppReq- AuxPwr+
> TransPend-
>                 LnkCap: Port #2, Speed 2.5GT/s, Width x1, ASPM L0s L1,
>                 Latency
> L0 <1us, L1 <4us
>                         ClockPM- Surprise- LLActRep+ BwNot-
>                 LnkCtl: ASPM Disabled; RCB 64 bytes Disabled- Retrain-
>                 CommClk-
>                         ExtSynch- ClockPM- AutWidDis- BWInt- AutBWInt-
>                 LnkSta: Speed 2.5GT/s, Width x0, TrErr- Train- SlotClk+
> DLActive- BWMgmt- ABWMgmt-
>                 SltCap: AttnBtn- PwrCtrl- MRL- AttnInd- PwrInd- HotPlug+
> Surprise+
>                         Slot #3, PowerLimit 6.500W; Interlock- NoCompl-
>                 SltCtl: Enable: AttnBtn- PwrFlt- MRL- PresDet+ CmdCplt-
>                 HPIrq-
> LinkChg-
>                         Control: AttnInd Unknown, PwrInd Unknown, 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-
>         Capabilities: [80] MSI: Enable+ Count=1/1 Maskable- 64bit-
>                 Address: fee0300c  Data: 4159
>         Capabilities: [90] Subsystem: Intel Corporation Device 1999
>         Capabilities: [a0] 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: [100 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-
>                 VC1:    Caps:   PATOffset=00 MaxTimeSlots=1 RejSnoopTrans-
>                         Arb:    Fixed+ WRR32- WRR64- WRR128- TWRR128- WRR256-
>                         Ctrl:   Enable- ID=0 ArbSelect=Fixed TC/VC=00
>                         Status: NegoPending- InProgress-
>         Capabilities: [180 v1] Root Complex Link
>                 Desc:   PortNumber=02 ComponentID=02 EltType=Config
>                 Link0:  Desc:   TargetPort=00 TargetComponent=02 AssocRCRB-
> LinkType=MemMapped LinkValid+
>                         Addr:   00000000fed1c001
>         Kernel driver in use: pcieport
>         Kernel modules: shpchp
> 
> 00:1c.2 PCI bridge: Intel Corporation N10/ICH 7 Family PCI Express Port 3
> (rev
> 02) (prog-if 00 [Normal decode])
>         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
>         Bus: primary=00, secondary=04, subordinate=04, sec-latency=0
>         I/O behind bridge: 00003000-00003fff
>         Memory behind bridge: f0200000-f02fffff
>         Prefetchable memory behind bridge: 0000000080000000-00000000801fffff
>         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] Express (v1) Root Port (Slot+), MSI 00
>                 DevCap: MaxPayload 128 bytes, PhantFunc 0, Latency L0s
> unlimited, L1 unlimited
>                         ExtTag- RBE- FLReset-
>                 DevCtl: Report errors: Correctable- Non-Fatal- Fatal-
> Unsupported-
>                         RlxdOrd- ExtTag- PhantFunc- AuxPwr- NoSnoop-
>                         MaxPayload 128 bytes, MaxReadReq 128 bytes
>                 DevSta: CorrErr- UncorrErr- FatalErr- UnsuppReq- AuxPwr+
> TransPend-
>                 LnkCap: Port #3, Speed 2.5GT/s, Width x1, ASPM L0s L1,
>                 Latency
> L0 <256ns, L1 <4us
>                         ClockPM- Surprise- LLActRep+ BwNot-
>                 LnkCtl: ASPM L0s 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-
>                 SltCap: AttnBtn- PwrCtrl- MRL- AttnInd- PwrInd- HotPlug+
> Surprise+
>                         Slot #4, PowerLimit 6.500W; Interlock- NoCompl-
>                 SltCtl: Enable: AttnBtn- PwrFlt- MRL- PresDet+ CmdCplt-
>                 HPIrq-
> LinkChg-
>                         Control: AttnInd Unknown, PwrInd Unknown, 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-
>         Capabilities: [80] MSI: Enable+ Count=1/1 Maskable- 64bit-
>                 Address: fee0300c  Data: 4161
>         Capabilities: [90] Subsystem: Intel Corporation Device 1999
>         Capabilities: [a0] 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: [100 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=01
>                         Status: NegoPending- InProgress-
>                 VC1:    Caps:   PATOffset=00 MaxTimeSlots=1 RejSnoopTrans-
>                         Arb:    Fixed+ WRR32- WRR64- WRR128- TWRR128- WRR256-
>                         Ctrl:   Enable- ID=0 ArbSelect=Fixed TC/VC=00
>                         Status: NegoPending- InProgress-
>         Capabilities: [180 v1] Root Complex Link
>                 Desc:   PortNumber=03 ComponentID=02 EltType=Config
>                 Link0:  Desc:   TargetPort=00 TargetComponent=02 AssocRCRB-
> LinkType=MemMapped LinkValid+
>                         Addr:   00000000fed1c001
>         Kernel driver in use: pcieport
>         Kernel modules: shpchp
> 
> 00:1d.0 USB Controller: Intel Corporation N10/ICH 7 Family USB UHCI
> Controller
> #1 (rev 02) (prog-if 00 [UHCI])
>         Subsystem: Lenovo Device 3807
>         Control: I/O+ Mem- BusMaster- SpecCycle- MemWINV- VGASnoop- ParErr-
> Stepping- SERR- FastB2B- DisINTx-
>         Status: Cap- 66MHz- UDF- FastB2B+ ParErr- DEVSEL=medium >TAbort-
> <TAbort- <MAbort- >SERR- <PERR- INTx-
>         Interrupt: pin A routed to IRQ 23
>         Region 4: I/O ports at 1820 [size=32]
>         Kernel driver in use: uhci_hcd
>         Kernel modules: uhci-hcd
> 
> 00:1d.1 USB Controller: Intel Corporation N10/ICH 7 Family USB UHCI
> Controller
> #2 (rev 02) (prog-if 00 [UHCI])
>         Subsystem: Lenovo Device 3808
>         Control: I/O+ Mem- BusMaster- SpecCycle- MemWINV- VGASnoop- ParErr-
> Stepping- SERR- FastB2B- DisINTx-
>         Status: Cap- 66MHz- UDF- FastB2B+ ParErr- DEVSEL=medium >TAbort-
> <TAbort- <MAbort- >SERR- <PERR- INTx-
>         Interrupt: pin B routed to IRQ 19
>         Region 4: I/O ports at 1840 [size=32]
>         Kernel driver in use: uhci_hcd
>         Kernel modules: uhci-hcd
> 
> 00:1d.2 USB Controller: Intel Corporation N10/ICH 7 Family USB UHCI
> Controller
> #3 (rev 02) (prog-if 00 [UHCI])
>         Subsystem: Lenovo Device 3809
>         Control: I/O+ Mem- BusMaster+ SpecCycle- MemWINV- VGASnoop- ParErr-
> Stepping- SERR- FastB2B- DisINTx-
>         Status: Cap- 66MHz- UDF- FastB2B+ ParErr- DEVSEL=medium >TAbort-
> <TAbort- <MAbort- >SERR- <PERR- INTx-
>         Latency: 0
>         Interrupt: pin C routed to IRQ 18
>         Region 4: I/O ports at 1860 [size=32]
>         Kernel driver in use: uhci_hcd
>         Kernel modules: uhci-hcd
> 
> 00:1d.3 USB Controller: Intel Corporation N10/ICH 7 Family USB UHCI
> Controller
> #4 (rev 02) (prog-if 00 [UHCI])
>         Subsystem: Lenovo Device 380a
>         Control: I/O+ Mem- BusMaster+ SpecCycle- MemWINV- VGASnoop- ParErr-
> Stepping- SERR- FastB2B- DisINTx-
>         Status: Cap- 66MHz- UDF- FastB2B+ ParErr- DEVSEL=medium >TAbort-
> <TAbort- <MAbort- >SERR- <PERR- INTx-
>         Latency: 0
>         Interrupt: pin D routed to IRQ 16
>         Region 4: I/O ports at 1880 [size=32]
>         Kernel driver in use: uhci_hcd
>         Kernel modules: uhci-hcd
> 
> 00:1d.7 USB Controller: Intel Corporation N10/ICH 7 Family USB2 EHCI
> Controller
> (rev 02) (prog-if 20 [EHCI])
>         Subsystem: Lenovo Device 380b
>         Control: I/O- Mem+ BusMaster+ SpecCycle- MemWINV- VGASnoop- ParErr-
> Stepping- SERR- FastB2B- DisINTx-
>         Status: Cap+ 66MHz- UDF- FastB2B+ ParErr- DEVSEL=medium >TAbort-
> <TAbort- <MAbort- >SERR- <PERR- INTx-
>         Latency: 0
>         Interrupt: pin A routed to IRQ 23
>         Region 0: Memory at f0644000 (32-bit, non-prefetchable) [size=1K]
>         Capabilities: [50] Power Management version 2
>                 Flags: PMEClk- DSI- D1- D2- AuxCurrent=375mA
> PME(D0+,D1-,D2-,D3hot+,D3cold+)
>                 Status: D0 NoSoftRst- PME-Enable- DSel=0 DScale=0 PME-
>         Capabilities: [58] Debug port: BAR=1 offset=00a0
>         Kernel driver in use: ehci_hcd
>         Kernel modules: ehci-hcd
> 
> 00:1e.0 PCI bridge: Intel Corporation 82801 Mobile PCI Bridge (rev e2)
> (prog-if
> 01 [Subtractive decode])
>         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
>         Bus: primary=00, secondary=05, subordinate=05, sec-latency=32
>         I/O behind bridge: 0000f000-00000fff
>         Memory behind bridge: fff00000-000fffff
>         Prefetchable memory behind bridge: 00000000fff00000-00000000000fffff
>         Secondary status: 66MHz- FastB2B+ ParErr- DEVSEL=medium >TAbort-
> <TAbort- <MAbort+ <SERR- <PERR-
>         BridgeCtl: Parity- SERR- NoISA- VGA- MAbort- >Reset- FastB2B-
>                 PriDiscTmr- SecDiscTmr- DiscTmrStat- DiscTmrSERREn-
>         Capabilities: [50] Subsystem: Lenovo Device 380c
> 
> 00:1f.0 ISA bridge: Intel Corporation 82801GBM (ICH7-M) LPC Interface Bridge
> (rev 02)
>         Subsystem: Lenovo Device 380d
>         Control: I/O+ Mem+ BusMaster+ SpecCycle- MemWINV- VGASnoop- ParErr-
> Stepping- SERR- FastB2B- DisINTx-
>         Status: Cap+ 66MHz- UDF- FastB2B- ParErr- DEVSEL=medium >TAbort-
> <TAbort- <MAbort- >SERR- <PERR- INTx-
>         Latency: 0
>         Capabilities: [e0] Vendor Specific Information: Len=0c <?>
>         Kernel modules: intel-rng, leds-ss4200, iTCO_wdt
> 
> 00:1f.1 IDE interface: Intel Corporation 82801G (ICH7 Family) IDE Controller
> (rev 02) (prog-if 8a [Master SecP PriP])
>         Subsystem: Lenovo Device 3810
>         Control: I/O+ Mem- BusMaster+ SpecCycle- MemWINV- VGASnoop- ParErr-
> Stepping- SERR- FastB2B- DisINTx-
>         Status: Cap- 66MHz- UDF- FastB2B+ ParErr- DEVSEL=medium >TAbort-
> <TAbort- <MAbort- >SERR- <PERR- INTx+
>         Latency: 0
>         Interrupt: pin B routed to IRQ 19
>         Region 0: I/O ports at 01f0 [size=8]
>         Region 1: I/O ports at 03f4 [size=1]
>         Region 2: I/O ports at 0170 [size=8]
>         Region 3: I/O ports at 0374 [size=1]
>         Region 4: I/O ports at 1810 [size=16]
>         Kernel driver in use: ata_piix
>         Kernel modules: piix, ata_piix
> 
> 00:1f.2 IDE interface: Intel Corporation 82801GBM/GHM (ICH7 Family) SATA IDE
> Controller (rev 02) (prog-if 8f [Master SecP SecO PriP PriO])
>         Subsystem: Lenovo Device 3835
>         Control: I/O+ Mem+ BusMaster+ SpecCycle- MemWINV- VGASnoop- ParErr-
> Stepping- SERR- FastB2B- DisINTx-
>         Status: Cap+ 66MHz+ UDF- FastB2B+ ParErr- DEVSEL=medium >TAbort-
> <TAbort- <MAbort- >SERR- <PERR- INTx-
>         Latency: 0
>         Interrupt: pin B routed to IRQ 19
>         Region 0: I/O ports at 18c8 [size=8]
>         Region 1: I/O ports at 18c0 [size=4]
>         Region 2: I/O ports at 18a8 [size=8]
>         Region 3: I/O ports at 180c [size=4]
>         Region 4: I/O ports at 18b0 [size=16]
>         Region 5: Memory at f0644400 (32-bit, non-prefetchable) [size=1K]
>         Capabilities: [70] 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-
>         Kernel driver in use: ata_piix
>         Kernel modules: ata_piix
> 
> 00:1f.3 SMBus: Intel Corporation N10/ICH 7 Family SMBus Controller (rev 02)
>         Subsystem: Lenovo Device 380f
>         Control: I/O+ Mem- BusMaster- SpecCycle- MemWINV- VGASnoop- ParErr-
> Stepping- SERR- FastB2B- DisINTx-
>         Status: Cap- 66MHz- UDF- FastB2B+ ParErr- DEVSEL=medium >TAbort-
> <TAbort- <MAbort- >SERR- <PERR- INTx-
>         Interrupt: pin B routed to IRQ 19
>         Region 4: I/O ports at 18e0 [size=32]
>         Kernel driver in use: i801_smbus
>         Kernel modules: i2c-i801
> 
> 02:00.0 Ethernet controller: Broadcom Corporation NetLink BCM5906M Fast
> Ethernet PCI Express (rev 02)
>         Subsystem: Lenovo IdeaPad S10e
>         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 44
>         Region 0: Memory at f0100000 (64-bit, non-prefetchable) [size=64K]
>         Expansion ROM at <ignored> [disabled]
>         Capabilities: [48] 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] Vital Product Data
>                 End
>         Capabilities: [58] Vendor Specific Information: Len=78 <?>
>         Capabilities: [e8] MSI: Enable+ Count=1/1 Maskable- 64bit+
>                 Address: 00000000fee0300c  Data: 4199
>         Capabilities: [d0] Express (v1) Endpoint, MSI 00
>                 DevCap: MaxPayload 128 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 4096 bytes
>                 DevSta: CorrErr+ UncorrErr- FatalErr- UnsuppReq- AuxPwr+
> TransPend-
>                 LnkCap: Port #0, Speed 2.5GT/s, Width x1, ASPM L0s L1,
>                 Latency
> L0 <4us, L1 <64us
>                         ClockPM+ Surprise- LLActRep- BwNot-
>                 LnkCtl: ASPM L0s 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-
>         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: [13c 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=01
>                         Status: NegoPending- InProgress-
>         Capabilities: [160 v1] Device Serial Number 00-23-8b-ff-fe-40-d5-e4
>         Kernel driver in use: tg3
>         Kernel modules: tg3
> 
> 04:00.0 Network controller: Broadcom Corporation BCM4312 802.11b/g LP-PHY
> (rev
> 01)
>         Subsystem: Broadcom Corporation Device 04b5
>         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 18
>         Region 0: Memory at f0200000 (64-bit, non-prefetchable) [size=16K]
>         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=2 PME-
>         Capabilities: [58] Vendor Specific Information: Len=78 <?>
>         Capabilities: [e8] MSI: Enable- Count=1/1 Maskable- 64bit+
>                 Address: 0000000000000000  Data: 0000
>         Capabilities: [d0] Express (v1) Endpoint, MSI 00
>                 DevCap: MaxPayload 128 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 128 bytes
>                 DevSta: CorrErr+ UncorrErr+ FatalErr- UnsuppReq+ AuxPwr-
> TransPend-
>                 LnkCap: Port #0, Speed 2.5GT/s, Width x1, ASPM L0s L1,
>                 Latency
> L0 <4us, L1 <64us
>                         ClockPM+ Surprise- LLActRep- BwNot-
>                 LnkCtl: ASPM L0s 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-
>         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: [13c 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=01
>                         Status: NegoPending- InProgress-
>         Capabilities: [160 v1] Device Serial Number 2e-19-00-ff-ff-91-00-21
>         Capabilities: [16c v1] Power Budgeting <?>
>         Kernel driver in use: b43-pci-bridge
>         Kernel modules: ssb
> 
> 
> 
> Thank you and please let me know if i can provide more info to debug. 
> Regards, Mark

One thing you could try is to modprobe the driver and then from another
terminal, do a `ps aux' and see if the modprobe is in "R", "D" or "S"
state.  Then do an

	echo t > /proc/sysrq-trigger

(or "echo w" if it was in D state) and then run "dmesg -s 1000000 >
foo", then send us the backtrace for that stuck modprobe instance. 
Please ensure that your email client doesn't wordwrap the trace!

Thanks.

On Wed, 1 Jun 2011 14:42:40 -0700
Andrew Morton <akpm@linux-foundation.org> wrote:

> (switched to email.  Please respond via emailed reply-to-all, not via the
> bugzilla web interface).
> 
> On Sat, 21 May 2011 20:17:32 GMT
> bugzilla-daemon@bugzilla.kernel.org wrote:
> 
> > https://bugzilla.kernel.org/show_bug.cgi?id=35572

whoa, that's creepy.  The report is ten days old, but in the two-minute
window between me reading it and then sending this email, Jean
responded in bugzilla.

Still, the backtrace might be useful.

Hello, 

thank you for advice to debug, the things I tried follow..

On Wednesday 01 of June 2011 23:42:40 Andrew Morton wrote:
> (switched to email.  Please respond via emailed reply-to-all, not via the
> bugzilla web interface).
> 
> On Sat, 21 May 2011 20:17:32 GMT
> 
> bugzilla-daemon@bugzilla.kernel.org wrote:
> > https://bugzilla.kernel.org/show_bug.cgi?id=35572
> > 
> >            Summary: eeprom module: modprobing hangs
> >            Product: Other
> >            Version: 2.5
> >     
> >     Kernel Version: 2.6.39
> >     
> >           Platform: All
> >         
> >         OS/Version: Linux
> >         
> >               Tree: Mainline
> >             
> >             Status: NEW
> >           
> >           Severity: normal
> >           Priority: P1
> >          
> >          Component: Modules
> >         
> >         AssignedTo: other_modules@kernel-bugs.osdl.org
> >         ReportedBy: markotahal@gmail.com
> >         Regression: No
> 
> This is drivers/misc/eeprom/eeprom.c?
> 
> That driver doesn't really have a maintainer.  Perhaps the i2c
> developers can help debug this?
> 
> > modbrobing eeprom module hangs, but does not crash the kernel. Occurs
> > with 2.6.39, with 2.6.38 and prev works ok.
> 
> So 2.6.38 did not have this bug?
> 
> The driver didn't change between .38 and .39.
Yes, it works ok on 2.6.38 kernel. Someone above suggested it might be related to i915 driver(?)
> 
> > Confirmed by other user, the bug
> > reported in Arch can be found here:
> > https://bugs.archlinux.org/24376
> > ....
> > Thank you and please let me know if i can provide more info to debug.
> > Regards, Mark
> 
> One thing you could try is to modprobe the driver and then from another
> terminal, do a `ps aux' and see if the modprobe is in "R", "D" or "S"
> state.  Then do an
modprobe is in D+ state.
> 
>       echo t > /proc/sysrq-trigger
> 
> (or "echo w" if it was in D state) and then run "dmesg -s 1000000 >
> foo", then send us the backtrace for that stuck modprobe instance.
> Please ensure that your email client doesn't wordwrap the trace!
I'm attaching the whole backtrace and adding the interesting part here too:
Thank you, Mark

PS: Is there a way to kill the modprobe process? ctrl+c nor kill -9 work for me, so i have to reboot every time.
 
-----------------------------------------------
[  462.667305] hda-intel: IRQ timing workaround is activated for card #0. Suggest a bigger bdl_pos_adj.
[  770.753437] [drm] GMBUS timed out, falling back to bit banging on pin 0 [i915 gmbus disabled]
[  770.806696] [drm] GMBUS timed out, falling back to bit banging on pin 0 [i915 gmbus disabled]
[  770.860064] [drm] GMBUS timed out, falling back to bit banging on pin 0 [i915 gmbus disabled]
[  770.913400] [drm] GMBUS timed out, falling back to bit banging on pin 0 [i915 gmbus disabled]
[  770.966721] [drm] GMBUS timed out, falling back to bit banging on pin 0 [i915 gmbus disabled]
[  771.020018] [drm] GMBUS timed out, falling back to bit banging on pin 0 [i915 gmbus disabled]
[  771.073382] [drm] GMBUS timed out, falling back to bit banging on pin 0 [i915 gmbus disabled]
[  771.126696] [drm] GMBUS timed out, falling back to bit banging on pin 0 [i915 gmbus disabled]
[  771.340045] [drm] GMBUS timed out, falling back to bit banging on pin 4 [i915 gmbus dpc]
[  961.296817] INFO: task modprobe:4538 blocked for more than 120 seconds.
[  961.296831] "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
[  961.296843] modprobe        D e1001bec     0  4538   4495 0x00000000
[  961.296865]  e1001bfc 00000086 00000002 e1001bec 00000001 e1001c63 e1001b72 e1001b76
[  961.296894]  00000000 33343030 ab3291d1 00000001 f14c2c00 e1001c30 00000001 c14e1440
[  961.296921]  f657ca00 c14e1440 f657c440 f4e6c000 f5862f70 e1001bc8 c11ad279 e1001bfc
[  961.296949] Call Trace:
[  961.296977]  [<c11ad279>] ? format_decode+0x319/0x380
[  961.296993]  [<c11af1aa>] ? vsnprintf+0x2ea/0x3d0
[  961.297060]  [<c132f1ed>] __mutex_lock_slowpath+0x10d/0x2b0
[  961.297133]  [<c132f39b>] mutex_lock+0xb/0x20
[  961.297188]  [<f805820d>] i2c_add_adapter+0x2d/0xa0 [i2c_core]
[  961.297239]  [<f806b90d>] __i2c_bit_add_bus+0x17d/0x2f0 [i2c_algo_bit]
[  961.297291]  [<f80581e0>] ? i2c_add_numbered_adapter+0xd0/0xd0 [i2c_core]
[  961.297342]  [<f806ba9d>] i2c_bit_add_bus+0xd/0x10 [i2c_algo_bit]
[  961.297415]  [<f82cd52b>] intel_gpio_create+0x11b/0x170 [i915]
[  961.297517]  [<f82ce4aa>] gmbus_xfer+0xbca/0xdf0 [i915]
[  961.297599]  [<f80583c5>] i2c_transfer+0x85/0xb0 [i2c_core]
[  961.297653]  [<f80586c4>] i2c_smbus_xfer+0x234/0x540 [i2c_core]
[  961.297671]  [<c11a0001>] ? blk_throtl_work+0x291/0x4d0
[  961.297687]  [<c131515b>] ? klist_add_tail+0x3b/0x50
[  961.297703]  [<c124c0df>] ? put_device+0xf/0x20
[  961.297718]  [<c124d123>] ? device_add+0x73/0x5f0
[  961.297788]  [<f8058f99>] i2c_default_probe+0xe9/0x130 [i2c_core]
[  961.297830]  [<c124c335>] ? device_for_each_child+0x45/0x50
[  961.297907]  [<f8059153>] i2c_do_add_adapter+0x173/0x260 [i2c_core]
[  961.297933]  [<c11a8fd8>] ? kobject_uevent_env+0xf8/0x430
[  961.297955]  [<c11a8e90>] ? add_uevent_var+0xc0/0xc0
[  961.298034]  [<f8059630>] ? i2c_del_adapter+0x1f0/0x1f0 [i2c_core]
[  961.298110]  [<f8059652>] __process_new_driver+0x22/0x2b [i2c_core]
[  961.298136]  [<c124e8e1>] bus_for_each_dev+0x41/0x70
[  961.298210]  [<f8059630>] ? i2c_del_adapter+0x1f0/0x1f0 [i2c_core]
[  961.298286]  [<f80577ab>] i2c_for_each_dev+0x2b/0x50 [i2c_core]
[  961.298365]  [<f8059630>] ? i2c_del_adapter+0x1f0/0x1f0 [i2c_core]
[  961.298441]  [<f80593bf>] i2c_register_driver+0x4f/0xa0 [i2c_core]
[  961.298470]  [<c1066c65>] ? notifier_call_chain.isra.0+0x45/0x60
[  961.298500]  [<f8710012>] eeprom_init+0x12/0x14 [eeprom]
[  961.298524]  [<c1001120>] do_one_initcall+0x30/0x170
[  961.298572]  [<f8710000>] ? 0xf870ffff
[  961.298599]  [<c107b453>] sys_init_module+0xe03/0x1a20
[  961.298738]  [<c1330edf>] sysenter_do_call+0x12/0x28
[ 1081.296837] INFO: task modprobe:4538 blocked for more than 120 seconds.
[ 1081.296855] "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
[ 1081.296871] modprobe        D e1001bec     0  4538   4495 0x00000000
[ 1081.296898]  e1001bfc 00000086 00000002 e1001bec 00000001 e1001c63 e1001b72 e1001b76
[ 1081.296938]  00000000 33343030 ab3291d1 00000001 f14c2c00 e1001c30 00000001 c14e1440
[ 1081.296980]  f657ca00 c14e1440 f657c440 f4e6c000 f5862f70 e1001bc8 c11ad279 e1001bfc
[ 1081.297019] Call Trace:
[ 1081.297055]  [<c11ad279>] ? format_decode+0x319/0x380
[ 1081.297079]  [<c11af1aa>] ? vsnprintf+0x2ea/0x3d0
[ 1081.297165]  [<c132f1ed>] __mutex_lock_slowpath+0x10d/0x2b0
[ 1081.297283]  [<c132f39b>] mutex_lock+0xb/0x20
[ 1081.297362]  [<f805820d>] i2c_add_adapter+0x2d/0xa0 [i2c_core]
[ 1081.297437]  [<f806b90d>] __i2c_bit_add_bus+0x17d/0x2f0 [i2c_algo_bit]
[ 1081.297515]  [<f80581e0>] ? i2c_add_numbered_adapter+0xd0/0xd0 [i2c_core]
[ 1081.297584]  [<f806ba9d>] i2c_bit_add_bus+0xd/0x10 [i2c_algo_bit]
[ 1081.297665]  [<f82cd52b>] intel_gpio_create+0x11b/0x170 [i915]
[ 1081.297767]  [<f82ce4aa>] gmbus_xfer+0xbca/0xdf0 [i915]
[ 1081.297867]  [<f80583c5>] i2c_transfer+0x85/0xb0 [i2c_core]
[ 1081.298032]  [<f80586c4>] i2c_smbus_xfer+0x234/0x540 [i2c_core]
[ 1081.298052]  [<c11a0001>] ? blk_throtl_work+0x291/0x4d0
[ 1081.298068]  [<c131515b>] ? klist_add_tail+0x3b/0x50
[ 1081.298084]  [<c124c0df>] ? put_device+0xf/0x20
[ 1081.298099]  [<c124d123>] ? device_add+0x73/0x5f0
[ 1081.298168]  [<f8058f99>] i2c_default_probe+0xe9/0x130 [i2c_core]
[ 1081.298185]  [<c124c335>] ? device_for_each_child+0x45/0x50
[ 1081.298239]  [<f8059153>] i2c_do_add_adapter+0x173/0x260 [i2c_core]
[ 1081.298258]  [<c11a8fd8>] ? kobject_uevent_env+0xf8/0x430
[ 1081.298273]  [<c11a8e90>] ? add_uevent_var+0xc0/0xc0
[ 1081.298329]  [<f8059630>] ? i2c_del_adapter+0x1f0/0x1f0 [i2c_core]
[ 1081.298381]  [<f8059652>] __process_new_driver+0x22/0x2b [i2c_core]
[ 1081.298399]  [<c124e8e1>] bus_for_each_dev+0x41/0x70
[ 1081.298452]  [<f8059630>] ? i2c_del_adapter+0x1f0/0x1f0 [i2c_core]
[ 1081.298505]  [<f80577ab>] i2c_for_each_dev+0x2b/0x50 [i2c_core]
[ 1081.298557]  [<f8059630>] ? i2c_del_adapter+0x1f0/0x1f0 [i2c_core]
[ 1081.298610]  [<f80593bf>] i2c_register_driver+0x4f/0xa0 [i2c_core]
[ 1081.298629]  [<c1066c65>] ? notifier_call_chain.isra.0+0x45/0x60
[ 1081.298647]  [<f8710012>] eeprom_init+0x12/0x14 [eeprom]
[ 1081.298663]  [<c1001120>] do_one_initcall+0x30/0x170
[ 1081.298697]  [<f8710000>] ? 0xf870ffff
[ 1081.298714]  [<c107b453>] sys_init_module+0xe03/0x1a20
[ 1081.298825]  [<c1330edf>] sysenter_do_call+0x12/0x28
[ 1201.296846] INFO: task modprobe:4538 blocked for more than 120 seconds.
[ 1201.296859] "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
[ 1201.296872] modprobe        D e1001bec     0  4538   4495 0x00000000
[ 1201.296893]  e1001bfc 00000086 00000002 e1001bec 00000001 e1001c63 e1001b72 e1001b76
[ 1201.296922]  00000000 33343030 ab3291d1 00000001 f14c2c00 e1001c30 00000001 c14e1440
[ 1201.296949]  f657ca00 c14e1440 f657c440 f4e6c000 f5862f70 e1001bc8 c11ad279 e1001bfc
[ 1201.296977] Call Trace:
[ 1201.297005]  [<c11ad279>] ? format_decode+0x319/0x380
[ 1201.297021]  [<c11af1aa>] ? vsnprintf+0x2ea/0x3d0
[ 1201.297090]  [<c132f1ed>] __mutex_lock_slowpath+0x10d/0x2b0
[ 1201.297164]  [<c132f39b>] mutex_lock+0xb/0x20
[ 1201.297231]  [<f805820d>] i2c_add_adapter+0x2d/0xa0 [i2c_core]
[ 1201.297370]  [<f806b90d>] __i2c_bit_add_bus+0x17d/0x2f0 [i2c_algo_bit]
[ 1201.297426]  [<f80581e0>] ? i2c_add_numbered_adapter+0xd0/0xd0 [i2c_core]
[ 1201.297477]  [<f806ba9d>] i2c_bit_add_bus+0xd/0x10 [i2c_algo_bit]
[ 1201.297550]  [<f82cd52b>] intel_gpio_create+0x11b/0x170 [i915]
[ 1201.297653]  [<f82ce4aa>] gmbus_xfer+0xbca/0xdf0 [i915]
[ 1201.297737]  [<f80583c5>] i2c_transfer+0x85/0xb0 [i2c_core]
[ 1201.297791]  [<f80586c4>] i2c_smbus_xfer+0x234/0x540 [i2c_core]
[ 1201.297809]  [<c11a0001>] ? blk_throtl_work+0x291/0x4d0
[ 1201.297826]  [<c131515b>] ? klist_add_tail+0x3b/0x50
[ 1201.297841]  [<c124c0df>] ? put_device+0xf/0x20
[ 1201.297856]  [<c124d123>] ? device_add+0x73/0x5f0
[ 1201.297927]  [<f8058f99>] i2c_default_probe+0xe9/0x130 [i2c_core]
[ 1201.297944]  [<c124c335>] ? device_for_each_child+0x45/0x50
[ 1201.297998]  [<f8059153>] i2c_do_add_adapter+0x173/0x260 [i2c_core]
[ 1201.298016]  [<c11a8fd8>] ? kobject_uevent_env+0xf8/0x430
[ 1201.298031]  [<c11a8e90>] ? add_uevent_var+0xc0/0xc0
[ 1201.298089]  [<f8059630>] ? i2c_del_adapter+0x1f0/0x1f0 [i2c_core]
[ 1201.298144]  [<f8059652>] __process_new_driver+0x22/0x2b [i2c_core]
[ 1201.298161]  [<c124e8e1>] bus_for_each_dev+0x41/0x70
[ 1201.298215]  [<f8059630>] ? i2c_del_adapter+0x1f0/0x1f0 [i2c_core]
[ 1201.298268]  [<f80577ab>] i2c_for_each_dev+0x2b/0x50 [i2c_core]
[ 1201.298332]  [<f8059630>] ? i2c_del_adapter+0x1f0/0x1f0 [i2c_core]
[ 1201.298408]  [<f80593bf>] i2c_register_driver+0x4f/0xa0 [i2c_core]
[ 1201.298436]  [<c1066c65>] ? notifier_call_chain.isra.0+0x45/0x60
[ 1201.298464]  [<f8710012>] eeprom_init+0x12/0x14 [eeprom]
[ 1201.298487]  [<c1001120>] do_one_initcall+0x30/0x170
[ 1201.298534]  [<f8710000>] ? 0xf870ffff
[ 1201.298560]  [<c107b453>] sys_init_module+0xe03/0x1a20
[ 1201.298727]  [<c1330edf>] sysenter_do_call+0x12/0x28
[ 1206.700674] SysRq : Show Blocked State
[ 1206.700688]   task                PC stack   pid father
[ 1206.700880] modprobe        D e1001bec     0  4538   4495 0x00000000
[ 1206.700897]  e1001bfc 00000086 00000002 e1001bec 00000001 e1001c63 e1001b72 e1001b76
[ 1206.700916]  00000000 33343030 ab3291d1 00000001 f14c2c00 e1001c30 00000001 c14e1440
[ 1206.700934]  f657ca00 c14e1440 f657c440 f4e6c000 f5862f70 e1001bc8 c11ad279 e1001bfc
[ 1206.700954] Call Trace:
[ 1206.700974]  [<c11ad279>] ? format_decode+0x319/0x380
[ 1206.700986]  [<c11af1aa>] ? vsnprintf+0x2ea/0x3d0
[ 1206.701046]  [<c132f1ed>] __mutex_lock_slowpath+0x10d/0x2b0
[ 1206.701127]  [<c132f39b>] mutex_lock+0xb/0x20
[ 1206.701178]  [<f805820d>] i2c_add_adapter+0x2d/0xa0 [i2c_core]
[ 1206.701227]  [<f806b90d>] __i2c_bit_add_bus+0x17d/0x2f0 [i2c_algo_bit]
[ 1206.701277]  [<f80581e0>] ? i2c_add_numbered_adapter+0xd0/0xd0 [i2c_core]
[ 1206.701325]  [<f806ba9d>] i2c_bit_add_bus+0xd/0x10 [i2c_algo_bit]
[ 1206.701388]  [<f82cd52b>] intel_gpio_create+0x11b/0x170 [i915]
[ 1206.701485]  [<f82ce4aa>] gmbus_xfer+0xbca/0xdf0 [i915]
[ 1206.701570]  [<f80583c5>] i2c_transfer+0x85/0xb0 [i2c_core]
[ 1206.701620]  [<f80586c4>] i2c_smbus_xfer+0x234/0x540 [i2c_core]
[ 1206.701636]  [<c11a0001>] ? blk_throtl_work+0x291/0x4d0
[ 1206.701649]  [<c131515b>] ? klist_add_tail+0x3b/0x50
[ 1206.701660]  [<c124c0df>] ? put_device+0xf/0x20
[ 1206.701671]  [<c124d123>] ? device_add+0x73/0x5f0
[ 1206.701737]  [<f8058f99>] i2c_default_probe+0xe9/0x130 [i2c_core]
[ 1206.701751]  [<c124c335>] ? device_for_each_child+0x45/0x50
[ 1206.701799]  [<f8059153>] i2c_do_add_adapter+0x173/0x260 [i2c_core]
[ 1206.701814]  [<c11a8fd8>] ? kobject_uevent_env+0xf8/0x430
[ 1206.701826]  [<c11a8e90>] ? add_uevent_var+0xc0/0xc0
[ 1206.701876]  [<f8059630>] ? i2c_del_adapter+0x1f0/0x1f0 [i2c_core]
[ 1206.701924]  [<f8059652>] __process_new_driver+0x22/0x2b [i2c_core]
[ 1206.701939]  [<c124e8e1>] bus_for_each_dev+0x41/0x70
[ 1206.701986]  [<f8059630>] ? i2c_del_adapter+0x1f0/0x1f0 [i2c_core]
[ 1206.702035]  [<f80577ab>] i2c_for_each_dev+0x2b/0x50 [i2c_core]
[ 1206.702084]  [<f8059630>] ? i2c_del_adapter+0x1f0/0x1f0 [i2c_core]
[ 1206.702132]  [<f80593bf>] i2c_register_driver+0x4f/0xa0 [i2c_core]
[ 1206.702149]  [<c1066c65>] ? notifier_call_chain.isra.0+0x45/0x60
[ 1206.702163]  [<f8710012>] eeprom_init+0x12/0x14 [eeprom]
[ 1206.702176]  [<c1001120>] do_one_initcall+0x30/0x170
[ 1206.702204]  [<f8710000>] ? 0xf870ffff
[ 1206.702218]  [<c107b453>] sys_init_module+0xe03/0x1a20
[ 1206.702338]  [<c1330edf>] sysenter_do_call+0x12/0x28
[ 1206.702354] Sched Debug Version: v0.10, 2.6.39-ARCH #1
[ 1206.702363] ktime                                   : 1206702.352548
[ 1206.702371] sched_clk                               : 1205697.782307
[ 1206.702379] cpu_clk                                 : 1206702.350662
[ 1206.702386] jiffies                                 : 272010
[ 1206.702392] sched_clock_stable                      : 0
[ 1206.702398] 
[ 1206.702401] sysctl_sched
[ 1206.702407]   .sysctl_sched_latency                    : 12.000000
[ 1206.702415]   .sysctl_sched_min_granularity            : 1.500000
[ 1206.702423]   .sysctl_sched_wakeup_granularity         : 2.000000
[ 1206.702430]   .sysctl_sched_child_runs_first           : 0
[ 1206.702436]   .sysctl_sched_features                   : 7279
[ 1206.702444]   .sysctl_sched_tunable_scaling            : 1 (logaritmic)
[ 1206.702452] 
[ 1206.702455] cpu#0, 1596.132 MHz
[ 1206.702460]   .nr_running                    : 3
[ 1206.702466]   .load                          : 2729
[ 1206.702472]   .nr_switches                   : 1666116
[ 1206.702478]   .nr_load_updates               : 220382
[ 1206.702484]   .nr_uninterruptible            : 1
[ 1206.702490]   .next_balance                  : 0.272012
[ 1206.702497]   .curr->pid                     : 4201
[ 1206.702505]   .clock                         : 1206700.465859
[ 1206.702511]   .cpu_load[0]                   : 541
[ 1206.702517]   .cpu_load[1]                   : 516
[ 1206.702523]   .cpu_load[2]                   : 322
[ 1206.702529]   .cpu_load[3]                   : 197
[ 1206.702536]   .cpu_load[4]                   : 144
[ 1206.702545] 
[ 1206.702547] cfs_rq[0]:/autogroup-37
[ 1206.702554]   .exec_clock                    : 0.000000
[ 1206.702562]   .MIN_vruntime                  : 0.000001
[ 1206.702569]   .min_vruntime                  : 4993.594736
[ 1206.702576]   .max_vruntime                  : 0.000001
[ 1206.702583]   .spread                        : 0.000000
[ 1206.702590]   .spread0                       : -892796.751521
[ 1206.702597]   .nr_spread_over                : 0
[ 1206.702603]   .nr_running                    : 1
[ 1206.702610]   .load                          : 1024
[ 1206.702617]   .load_avg                      : 0.000000
[ 1206.702624]   .load_period                   : 9.999999
[ 1206.702630]   .load_contrib                  : 0
[ 1206.702637]   .load_tg                       : 0
[ 1206.702645]   .se->exec_start                : 1206700.465859
[ 1206.702652]   .se->vruntime                  : 897784.646895
[ 1206.702660]   .se->sum_exec_runtime          : 4949.823694
[ 1206.702666]   .se->load.weight               : 1024
[ 1206.702675] 
[ 1206.702678] cfs_rq[0]:/autogroup-20
[ 1206.702684]   .exec_clock                    : 0.000000
[ 1206.702692]   .MIN_vruntime                  : 0.000001
[ 1206.702699]   .min_vruntime                  : 82651.825963
[ 1206.702706]   .max_vruntime                  : 0.000001
[ 1206.702713]   .spread                        : 0.000000
[ 1206.702721]   .spread0                       : -815138.520294
[ 1206.702727]   .nr_spread_over                : 0
[ 1206.702733]   .nr_running                    : 0
[ 1206.702740]   .load                          : 0
[ 1206.702747]   .load_avg                      : 6057.359872
[ 1206.702754]   .load_period                   : 9.071832
[ 1206.702760]   .load_contrib                  : 667
[ 1206.702767]   .load_tg                       : 1574
[ 1206.702775]   .se->exec_start                : 1206700.003418
[ 1206.702783]   .se->vruntime                  : 897790.346257
[ 1206.702790]   .se->sum_exec_runtime          : 82669.707003
[ 1206.702797]   .se->load.weight               : 2
[ 1206.702805] 
[ 1206.702808] cfs_rq[0]:/autogroup-32
[ 1206.702814]   .exec_clock                    : 0.000000
[ 1206.702822]   .MIN_vruntime                  : 289034.537793
[ 1206.702829]   .min_vruntime                  : 289035.678598
[ 1206.702837]   .max_vruntime                  : 289034.537793
[ 1206.702844]   .spread                        : 0.000000
[ 1206.702852]   .spread0                       : -608754.667659
[ 1206.702858]   .nr_spread_over                : 0
[ 1206.702865]   .nr_running                    : 1
[ 1206.702871]   .load                          : 1024
[ 1206.702877]   .load_avg                      : 2606.827683
[ 1206.702884]   .load_period                   : 7.060708
[ 1206.702891]   .load_contrib                  : 394
[ 1206.702897]   .load_tg                       : 909
[ 1206.702905]   .se->exec_start                : 1206699.263284
[ 1206.702913]   .se->vruntime                  : 897785.937817
[ 1206.702920]   .se->sum_exec_runtime          : 472433.308035
[ 1206.702927]   .se->load.weight               : 681
[ 1206.702934] 
[ 1206.702936] cfs_rq[0]:/
[ 1206.702942]   .exec_clock                    : 0.000000
[ 1206.702950]   .MIN_vruntime                  : 897784.346257
[ 1206.702958]   .min_vruntime                  : 897790.346257
[ 1206.702965]   .max_vruntime                  : 897785.937817
[ 1206.702972]   .spread                        : 1.591560
[ 1206.702979]   .spread0                       : 0.000000
[ 1206.702986]   .nr_spread_over                : 0
[ 1206.702993]   .nr_running                    : 3
[ 1206.702999]   .load                          : 2729
[ 1206.703006]   .load_avg                      : 0.000000
[ 1206.703013]   .load_period                   : 0.000000
[ 1206.703019]   .load_contrib                  : 0
[ 1206.703026]   .load_tg                       : 0
[ 1206.703033] 
[ 1206.703036] runnable tasks:
[ 1206.703039]             task   PID         tree-key  switches  prio     exec-runtime         sum-exec        sum-sleep
[ 1206.703044] ----------------------------------------------------------------------------------------------------------
[ 1206.703161]          firefox  3926    289034.537793    264413   120               0               0               0.000000               0.000000               0.000000 /autogroup-32
[ 1206.703205] R           bash  4201      4993.594736       118   120               0               0               0.000000               0.000000               0.000000 /autogroup-37
[ 1206.703232]      kworker/0:3  4750    897784.346257      2597   120               0               0               0.000000               0.000000               0.000000 /
[ 1206.703256] 
[ 1206.703258] cpu#1, 1596.132 MHz
[ 1206.703264]   .nr_running                    : 3
[ 1206.703270]   .load                          : 1478
[ 1206.703277]   .nr_switches                   : 1715530
[ 1206.703283]   .nr_load_updates               : 200464
[ 1206.703290]   .nr_uninterruptible            : 0
[ 1206.703296]   .next_balance                  : 0.272020
[ 1206.703302]   .curr->pid                     : 3005
[ 1206.703310]   .clock                         : 1206703.243963
[ 1206.703316]   .cpu_load[0]                   : 1478
[ 1206.703322]   .cpu_load[1]                   : 1026
[ 1206.703328]   .cpu_load[2]                   : 633
[ 1206.703334]   .cpu_load[3]                   : 397
[ 1206.703340]   .cpu_load[4]                   : 292
[ 1206.703349] 
[ 1206.703351] cfs_rq[1]:/autogroup-20
[ 1206.703357]   .exec_clock                    : 0.000000
[ 1206.703365]   .MIN_vruntime                  : 0.000001
[ 1206.703372]   .min_vruntime                  : 72584.908065
[ 1206.703379]   .max_vruntime                  : 0.000001
[ 1206.703386]   .spread                        : 0.000000
[ 1206.703393]   .spread0                       : -825205.438192
[ 1206.703400]   .nr_spread_over                : 0
[ 1206.703406]   .nr_running                    : 0
[ 1206.703412]   .load                          : 1024
[ 1206.703419]   .load_avg                      : 4124.161792
[ 1206.703427]   .load_period                   : 5.380653
[ 1206.703432]   .load_contrib                  : 774
[ 1206.703438]   .load_tg                       : 1441
[ 1206.703446]   .se->exec_start                : 1206703.408312
[ 1206.703454]   .se->vruntime                  : 919383.747396
[ 1206.703461]   .se->sum_exec_runtime          : 72594.153351
[ 1206.703467]   .se->load.weight               : 620
[ 1206.703475] 
[ 1206.703478] cfs_rq[1]:/autogroup-9
[ 1206.703485]   .exec_clock                    : 0.000000
[ 1206.703492]   .MIN_vruntime                  : 0.000001
[ 1206.703499]   .min_vruntime                  : 4998.478127
[ 1206.703506]   .max_vruntime                  : 0.000001
[ 1206.703513]   .spread                        : 0.000000
[ 1206.703516]   .spread0                       : -892791.868130
[ 1206.703516]   .nr_spread_over                : 0
[ 1206.703516]   .nr_running                    : 0
[ 1206.703516]   .load                          : 0
[ 1206.703516]   .load_avg                      : 1279.999872
[ 1206.703516]   .load_period                   : 8.070143
[ 1206.703516]   .load_contrib                  : 158
[ 1206.703516]   .load_tg                       : 158
[ 1206.703516]   .se->exec_start                : 1206681.362771
[ 1206.703516]   .se->vruntime                  : 919375.864455
[ 1206.703516]   .se->sum_exec_runtime          : 2512.975151
[ 1206.703516]   .se->load.weight               : 2
[ 1206.703516] 
[ 1206.703516] cfs_rq[1]:/autogroup-32
[ 1206.703516]   .exec_clock                    : 0.000000
[ 1206.703516]   .MIN_vruntime                  : 287717.141074
[ 1206.703516]   .min_vruntime                  : 287720.953312
[ 1206.703516]   .max_vruntime                  : 287717.141074
[ 1206.703516]   .spread                        : 0.000000
[ 1206.703516]   .spread0                       : -610069.392945
[ 1206.703516]   .nr_spread_over                : 0
[ 1206.703516]   .nr_running                    : 2
[ 1206.703516]   .load                          : 2048
[ 1206.703516]   .load_avg                      : 2929.511347
[ 1206.703516]   .load_period                   : 5.367701
[ 1206.703516]   .load_contrib                  : 515
[ 1206.703516]   .load_tg                       : 909
[ 1206.703516]   .se->exec_start                : 1206703.534125
[ 1206.703516]   .se->vruntime                  : 919387.199619
[ 1206.703516]   .se->sum_exec_runtime          : 464780.243939
[ 1206.703516]   .se->load.weight               : 858
[ 1206.703516] 
[ 1206.703516] cfs_rq[1]:/
[ 1206.703516]   .exec_clock                    : 0.000000
[ 1206.703516]   .MIN_vruntime                  : 919383.908395
[ 1206.703516]   .min_vruntime                  : 919387.199619
[ 1206.703516]   .max_vruntime                  : 919383.908395
[ 1206.703516]   .spread                        : 0.000000
[ 1206.703516]   .spread0                       : 21596.853362
[ 1206.703516]   .nr_spread_over                : 0
[ 1206.703516]   .nr_running                    : 2
[ 1206.703516]   .load                          : 1478
[ 1206.703516]   .load_avg                      : 0.000000
[ 1206.703516]   .load_period                   : 0.000000
[ 1206.703516]   .load_contrib                  : 0
[ 1206.703516]   .load_tg                       : 0
[ 1206.703516] 
[ 1206.703516] runnable tasks:
[ 1206.703516]             task   PID         tree-key  switches  prio     exec-runtime         sum-exec        sum-sleep
[ 1206.703516] ----------------------------------------------------------------------------------------------------------
[ 1206.703516]                X  3005     72585.005702    398233   120               0               0               0.000000               0.000000               0.000000 /autogroup-20
[ 1206.703516] R           kwin  3673    287716.183317    287687   120               0               0               0.000000               0.000000               0.000000 /autogroup-32
[ 1206.703516]          konsole  3749    287717.141074     12943   120               0               0               0.000000               0.000000               0.000000 /autogroup-32
[ 1206.703516]
-----------------------------------------------
> 
> Thanks.

-- 

Marek Otahal :o)

Created attachment 60542 [details]
dmesg after modprobe and sysrq+w

On Thu, 2 Jun 2011 17:53:42 +0200, Marek Otahal wrote:
> I'm attaching the whole backtrace and adding the interesting part here too:
> Thank you, Mark
> 
> PS: Is there a way to kill the modprobe process? ctrl+c nor kill -9 work for
> me, so i have to reboot every time.

I don't think there is another way, sorry.

> -----------------------------------------------
> [  462.667305] hda-intel: IRQ timing workaround is activated for card #0.
> Suggest a bigger bdl_pos_adj.
> [  770.753437] [drm] GMBUS timed out, falling back to bit banging on pin 0
> [i915 gmbus disabled]
> [  770.806696] [drm] GMBUS timed out, falling back to bit banging on pin 0
> [i915 gmbus disabled]
> [  770.860064] [drm] GMBUS timed out, falling back to bit banging on pin 0
> [i915 gmbus disabled]
> [  770.913400] [drm] GMBUS timed out, falling back to bit banging on pin 0
> [i915 gmbus disabled]
> [  770.966721] [drm] GMBUS timed out, falling back to bit banging on pin 0
> [i915 gmbus disabled]
> [  771.020018] [drm] GMBUS timed out, falling back to bit banging on pin 0
> [i915 gmbus disabled]
> [  771.073382] [drm] GMBUS timed out, falling back to bit banging on pin 0
> [i915 gmbus disabled]
> [  771.126696] [drm] GMBUS timed out, falling back to bit banging on pin 0
> [i915 gmbus disabled]
> [  771.340045] [drm] GMBUS timed out, falling back to bit banging on pin 4
> [i915 gmbus dpc]
> [  961.296817] INFO: task modprobe:4538 blocked for more than 120 seconds.
> [  961.296831] "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables
> this message.
> [  961.296843] modprobe        D e1001bec     0  4538   4495 0x00000000
> [  961.296865]  e1001bfc 00000086 00000002 e1001bec 00000001 e1001c63
> e1001b72 e1001b76
> [  961.296894]  00000000 33343030 ab3291d1 00000001 f14c2c00 e1001c30
> 00000001 c14e1440
> [  961.296921]  f657ca00 c14e1440 f657c440 f4e6c000 f5862f70 e1001bc8
> c11ad279 e1001bfc
> [  961.296949] Call Trace:
> [  961.296977]  [<c11ad279>] ? format_decode+0x319/0x380
> [  961.296993]  [<c11af1aa>] ? vsnprintf+0x2ea/0x3d0
> [  961.297060]  [<c132f1ed>] __mutex_lock_slowpath+0x10d/0x2b0
> [  961.297133]  [<c132f39b>] mutex_lock+0xb/0x20
> [  961.297188]  [<f805820d>] i2c_add_adapter+0x2d/0xa0 [i2c_core]
> [  961.297239]  [<f806b90d>] __i2c_bit_add_bus+0x17d/0x2f0 [i2c_algo_bit]
> [  961.297291]  [<f80581e0>] ? i2c_add_numbered_adapter+0xd0/0xd0 [i2c_core]
> [  961.297342]  [<f806ba9d>] i2c_bit_add_bus+0xd/0x10 [i2c_algo_bit]
> [  961.297415]  [<f82cd52b>] intel_gpio_create+0x11b/0x170 [i915]
> [  961.297517]  [<f82ce4aa>] gmbus_xfer+0xbca/0xdf0 [i915]
> [  961.297599]  [<f80583c5>] i2c_transfer+0x85/0xb0 [i2c_core]
> [  961.297653]  [<f80586c4>] i2c_smbus_xfer+0x234/0x540 [i2c_core]
> [  961.297671]  [<c11a0001>] ? blk_throtl_work+0x291/0x4d0
> [  961.297687]  [<c131515b>] ? klist_add_tail+0x3b/0x50
> [  961.297703]  [<c124c0df>] ? put_device+0xf/0x20
> [  961.297718]  [<c124d123>] ? device_add+0x73/0x5f0
> [  961.297788]  [<f8058f99>] i2c_default_probe+0xe9/0x130 [i2c_core]
> [  961.297830]  [<c124c335>] ? device_for_each_child+0x45/0x50
> [  961.297907]  [<f8059153>] i2c_do_add_adapter+0x173/0x260 [i2c_core]
> [  961.297933]  [<c11a8fd8>] ? kobject_uevent_env+0xf8/0x430
> [  961.297955]  [<c11a8e90>] ? add_uevent_var+0xc0/0xc0
> [  961.298034]  [<f8059630>] ? i2c_del_adapter+0x1f0/0x1f0 [i2c_core]
> [  961.298110]  [<f8059652>] __process_new_driver+0x22/0x2b [i2c_core]
> [  961.298136]  [<c124e8e1>] bus_for_each_dev+0x41/0x70
> [  961.298210]  [<f8059630>] ? i2c_del_adapter+0x1f0/0x1f0 [i2c_core]
> [  961.298286]  [<f80577ab>] i2c_for_each_dev+0x2b/0x50 [i2c_core]
> [  961.298365]  [<f8059630>] ? i2c_del_adapter+0x1f0/0x1f0 [i2c_core]
> [  961.298441]  [<f80593bf>] i2c_register_driver+0x4f/0xa0 [i2c_core]
> [  961.298470]  [<c1066c65>] ? notifier_call_chain.isra.0+0x45/0x60
> [  961.298500]  [<f8710012>] eeprom_init+0x12/0x14 [eeprom]
> [  961.298524]  [<c1001120>] do_one_initcall+0x30/0x170
> [  961.298572]  [<f8710000>] ? 0xf870ffff
> [  961.298599]  [<c107b453>] sys_init_module+0xe03/0x1a20
> [  961.298738]  [<c1330edf>] sysenter_do_call+0x12/0x28

OK, I see what's going on. This is a deadlock on i2c-core's main mutex
(drivers/i2c/i2c-core.c:core_lock). It is taken a first time by the
eeprom driver, to walk all the i2c adapters in search for supported
devices. Then it is taken a second time by the i915 driver, when it
attempts to register a new i2c adapter in the middle of the operation.

This only happens with the eeprom driver because legacy device
detection is only enabled on i915 for class I2C_CLASS_DDC, which in
turn is only set by the eeprom driver.

This only happens with the i915 driver, because it attempts to create a
new i2c adapter in the middle of a transaction. This is very uncommon,
the i2c core was never designed for this.

I suspect that the regression is caused by
8f9a3f9b63b8cd3f03be9dc53533f90bd4120e5f. Before this commit, the
software bit-banged interface was created earlier. So I would suggest
that we revert this commit from 2.6.39 and upstream for the time being.

For the long term, I think that the i2c implementation of i915 should
be reworked. Having two i2c adapters per actual bus, one for hardware
controlled and one for software controlled, is confusing and dangerous.
And creating a bus on the fly in the middle of a transaction is just as
bad. If you really can't instantiate only the one you need, then you
should instantiate the software controlled one (i2c_bit_add_adapter),
then update the algorithm to switch to hardware controlled where
possible, and ultimately undo that update if the hardware controller
turns out to be non-working. I can't write the code as I don't have any
supported piece of hardware and I'm not familiar with the code, but I
can help review any patch if you want.

On Thu, 2 Jun 2011 16:17:42 +0200, Jean Delvare <khali@linux-fr.org> wrote:
> For the long term, I think that the i2c implementation of i915 should
> be reworked. Having two i2c adapters per actual bus, one for hardware
> controlled and one for software controlled, is confusing and dangerous.
> And creating a bus on the fly in the middle of a transaction is just as
> bad. If you really can't instantiate only the one you need, then you
> should instantiate the software controlled one (i2c_bit_add_adapter),
> then update the algorithm to switch to hardware controlled where
> possible, and ultimately undo that update if the hardware controller
> turns out to be non-working. I can't write the code as I don't have any
> supported piece of hardware and I'm not familiar with the code, but I
> can help review any patch if you want.

Reading email, in reverse order...

Thanks Jean, I will try to do you've outlined.
-Chris

Created attachment 60812 [details]
Fix for kernel 2.6.39

Patch : https://bugzilla.kernel.org/attachment.cgi?id=60812
Handled-By : Jean Delvare <khali@linux-fr.org>

Fix merged for 3.0-rc4:
 http://git.kernel.org/linus/826c7e4147f902737b281e8a5a7d7aa33fd63316

A patch referencing this bug report has been merged in Linux v3.4-rc1:

commit c3dfefa0a6d235bd465309e12f4c56ea16e71111
Author: Daniel Vetter <daniel.vetter@ffwll.ch>
Date:   Tue Feb 14 22:37:25 2012 +0100

    drm/i915: reenable gmbus on gen3+ again

A patch referencing a commit referencing this bug report has been merged in Linux v3.4-rc3:

commit 6a562e3daee217ce99fe0e31150acd89a5b22606
Author: Daniel Vetter <daniel.vetter@ffwll.ch>
Date:   Mon Apr 9 21:10:38 2012 +0200

    Revert "drm/i915: reenable gmbus on gen3+ again"

A patch referencing a commit referencing this bug report has been merged in Linux v3.6-rc3:

commit f1a2f5b7c5f0941d23eef0a095c0b99bf8d051e6
Author: Jani Nikula <jani.nikula@intel.com>
Date:   Mon Aug 13 13:22:35 2012 +0300

    drm/i915: fall back to bit-banging if GMBUS fails in CRT EDID reads