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527139d738d7 ("PCI/sysfs: Convert "rom" to static attribute")

REGRESSION Ville Syrjälä 4 participants 10 messages Dec 17, 2021 – Jan 25, 2022

Subsystems (3)
x86 PCI Regressions
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Ville Syrjälä

author
#0 lore raw

Hi,

The pci sysfs "rom" file has disappeared for VGA devices. Looks to be a regression from commit 527139d738d7 ("PCI/sysfs:
Convert "rom" to static attribute").

Some kind of ordering issue between the sysfs file creation vs. pci_fixup_video() perhaps?

Signature · 2 lines
Ville Syrjälä
Intel
#1 lore raw

Hi Ville,

Thanks for the report!

Quoted 8 lines · Ville Syrjälä

Hi,

The pci sysfs "rom" file has disappeared for VGA devices. Looks to be a regression from commit 527139d738d7 ("PCI/sysfs:
Convert "rom" to static attribute").

Some kind of ordering issue between the sysfs file creation vs. pci_fixup_video() perhaps?

Can you attach your complete "lspci -vv" output? Also, which is the default device? I think there's a "boot_vga" sysfs file that shows this. "find /sys -name boot_vga | xargs grep ."

I think the relevant path is something like this:

acpi_pci_root_add

    pci_acpi_scan_root
      ...
        pci_scan_single_device
          pci_device_add
            device_add
              ...
                sysfs_create_groups
                  ...
                    if (grp->is_visible())
                      pci_dev_rom_attr_is_visible  # after 527139d738d7
                        if (pci_resource_len(pdev, PCI_ROM_RESOURCE))
                          ...
    pci_bus_add_devices
      pci_bus_add_device
        pci_fixup_device(pci_fixup_final)
          pci_fixup_video
            if (vga_default_device() ...)
              # update PCI_ROM_RESOURCE
        pci_create_sysfs_dev_files
          if (pci_resource_len(pdev, PCI_ROM_RESOURCE))
            sysfs_create_bin_file("rom")           # before 527139d738d7

Prior to 527139d738d7, we ran pci_fixup_video() in pci_bus_add_devices(). The vga_default_device() there might depend on the fact that we've discovered all the PCI devices.

After 527139d738d7, we create the "rom" file in pci_device_add(), which happens as we discover each device, so maybe we don't yet know which device is the default VGA device.

Bjorn

author
#2 lore raw
Quoted 11 lines · Bjorn Helgaas

Hi Ville,

Thanks for the report!

Quoted 6 lines · Ville Syrjälä

Hi,

The pci sysfs "rom" file has disappeared for VGA devices. Looks to be a regression from commit 527139d738d7 ("PCI/sysfs:
Convert "rom" to static attribute").

Quoted 6 lines
Quoted 2 lines

Some kind of ordering issue between the sysfs file creation vs. pci_fixup_video() perhaps?

Can you attach your complete "lspci -vv" output? Also, which is the default device? I think there's a "boot_vga" sysfs file that shows this. "find /sys -name boot_vga | xargs grep ."

All I have is Intel iGPUs so it's always 00:02.0.

$ cat /sys/bus/pci/devices/0000\:00\:02.0/boot_vga 
1
$ cat /sys/bus/pci/devices/0000\:00\:02.0/rom
cat: '/sys/bus/pci/devices/0000:00:02.0/rom': No such file or directory

I've attached the full lspci from my IVB laptop, but the problem happens on every machine (with an iGPU at least).

I presume with a discrete GPU it might not happen since they actually have a real ROM.

Quoted 35 lines

I think the relevant path is something like this:

acpi_pci_root_add

    pci_acpi_scan_root
      ...
        pci_scan_single_device
          pci_device_add
            device_add
              ...
                sysfs_create_groups
                  ...
                    if (grp->is_visible())
                      pci_dev_rom_attr_is_visible  # after 527139d738d7
                        if (pci_resource_len(pdev, PCI_ROM_RESOURCE))
                          ...
    pci_bus_add_devices
      pci_bus_add_device
        pci_fixup_device(pci_fixup_final)
          pci_fixup_video
            if (vga_default_device() ...)
              # update PCI_ROM_RESOURCE
        pci_create_sysfs_dev_files
          if (pci_resource_len(pdev, PCI_ROM_RESOURCE))
            sysfs_create_bin_file("rom")           # before 527139d738d7

Prior to 527139d738d7, we ran pci_fixup_video() in pci_bus_add_devices(). The vga_default_device() there might depend on the fact that we've discovered all the PCI devices.

After 527139d738d7, we create the "rom" file in pci_device_add(), which happens as we discover each device, so maybe we don't yet know which device is the default VGA device.

Bjorn

Signature · 2 lines
Ville Syrjälä
Intel

00:00.0 Host bridge: Intel Corporation 3rd Gen Core processor DRAM Controller (rev 09)
Subsystem: Lenovo 3rd Gen Core processor DRAM Controller
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=0c <?>
Kernel driver in use: ivb_uncore

00:02.0 VGA compatible controller: Intel Corporation 3rd Gen Core processor Graphics Controller (rev 09) (prog-if 00 [VGA controller])
Subsystem: Lenovo 3rd Gen Core processor Graphics Controller
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 27
Region 0: Memory at f0000000 (64-bit, non-prefetchable) [size=4M]
Region 2: Memory at e0000000 (64-bit, prefetchable) [size=256M]
Region 4: I/O ports at 4000 [size=64]
Expansion ROM at 000c0000 [virtual] [disabled] [size=128K]
Capabilities: [90] MSI: Enable+ Count=1/1 Maskable- 64bit-
Address: fee01004 Data: 002b
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-
Capabilities: [a4] PCI Advanced Features
AFCap: TP+ FLR+
AFCtrl: FLR-
AFStatus: TP-
Kernel driver in use: i915
Kernel modules: i915

00:14.0 USB controller: Intel Corporation 7 Series/C210 Series Chipset Family USB xHCI Host Controller (rev 04) (prog-if 30 [XHCI])
Subsystem: Lenovo 7 Series/C210 Series Chipset Family USB xHCI Host Controller
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 25
Region 0: Memory at f1500000 (64-bit, non-prefetchable) [size=64K]
Capabilities: [70] Power Management version 2
Flags: PMEClk- DSI- D1- D2- AuxCurrent=375mA PME(D0-,D1-,D2-,D3hot+,D3cold+)
Status: D3 NoSoftRst+ PME-Enable+ DSel=0 DScale=0 PME-
Capabilities: [80] MSI: Enable+ Count=1/8 Maskable- 64bit+
Address: 00000000fee01004 Data: 0029
Kernel driver in use: xhci_hcd
Kernel modules: xhci_pci

00:16.0 Communication controller: Intel Corporation 7 Series/C216 Chipset Family MEI Controller #1 (rev 04)
Subsystem: Lenovo 7 Series/C216 Chipset Family MEI Controller
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 255
Region 0: Memory at f1515000 (64-bit, non-prefetchable) [size=16]
Capabilities: [50] 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: [8c] MSI: Enable- Count=1/1 Maskable- 64bit+
Address: 0000000000000000 Data: 0000

00:1a.0 USB controller: Intel Corporation 7 Series/C216 Chipset Family USB Enhanced Host Controller #2 (rev 04) (prog-if 20 [EHCI])
Subsystem: Lenovo 7 Series/C216 Chipset Family USB Enhanced Host Controller
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 16
Region 0: Memory at f151a000 (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: D3 NoSoftRst- PME-Enable+ DSel=0 DScale=0 PME-
Capabilities: [58] Debug port: BAR=1 offset=00a0
Capabilities: [98] PCI Advanced Features
AFCap: TP+ FLR+
AFCtrl: FLR-
AFStatus: TP-
Kernel driver in use: ehci-pci
Kernel modules: ehci_pci

00:1b.0 Audio device: Intel Corporation 7 Series/C216 Chipset Family High Definition Audio Controller (rev 04)
Subsystem: Lenovo 7 Series/C216 Chipset Family High Definition Audio Controller
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 28
Region 0: Memory at f1510000 (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: 00000000fee02004 Data: 0021
Capabilities: [70] Express (v1) Root Complex Integrated Endpoint, MSI 00
DevCap: MaxPayload 128 bytes, PhantFunc 0
ExtTag- RBE- FLReset+
DevCtl: CorrErr- NonFatalErr- FatalErr- UnsupReq-
RlxdOrd- ExtTag- PhantFunc- AuxPwr- NoSnoop- FLReset-
MaxPayload 128 bytes, MaxReadReq 128 bytes
DevSta: CorrErr- NonFatalErr- FatalErr- UnsupReq- AuxPwr+ TransPend-
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=22
Status: NegoPending- InProgress-
Capabilities: [130 v1] Root Complex Link
Desc: PortNumber=0f ComponentID=00 EltType=Config
Link0: Desc: TargetPort=00 TargetComponent=00 AssocRCRB- LinkType=MemMapped LinkValid+
Addr: 00000000fed1c000
Kernel driver in use: snd_hda_intel
Kernel modules: snd_hda_intel

00:1c.0 PCI bridge: Intel Corporation 7 Series/C216 Chipset Family PCI Express Root Port 1 (rev c4) (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
Interrupt: pin A routed to IRQ 16
Bus: primary=00, secondary=02, subordinate=02, sec-latency=0
I/O behind bridge: 00003000-00003fff [size=4K]
Memory behind bridge: f0d00000-f14fffff [size=8M]
Prefetchable memory behind bridge: 00000000f0400000-00000000f0bfffff [size=8M]
Secondary status: 66MHz- FastB2B- ParErr- DEVSEL=fast >TAbort- <TAbort- <MAbort- <SERR- <PERR-
BridgeCtl: Parity- SERR+ NoISA- VGA- VGA16- MAbort- >Reset- FastB2B-
PriDiscTmr- SecDiscTmr- DiscTmrStat- DiscTmrSERREn-
Capabilities: [40] Express (v2) Root Port (Slot+), MSI 00
DevCap: MaxPayload 128 bytes, PhantFunc 0
ExtTag- RBE+
DevCtl: CorrErr- NonFatalErr- FatalErr- UnsupReq-
RlxdOrd- ExtTag- PhantFunc- AuxPwr- NoSnoop-
MaxPayload 128 bytes, MaxReadReq 128 bytes
DevSta: CorrErr- NonFatalErr- FatalErr- UnsupReq- AuxPwr+ TransPend-
LnkCap: Port #1, Speed 5GT/s, Width x1, ASPM L0s L1, Exit Latency L0s <512ns, L1 <16us
ClockPM- Surprise- LLActRep+ BwNot- ASPMOptComp-
LnkCtl: ASPM L1 Enabled; RCB 64 bytes, Disabled- CommClk+
ExtSynch- ClockPM- AutWidDis- BWInt- AutBWInt-
LnkSta: Speed 2.5GT/s (downgraded), Width x1 (ok)
TrErr- Train- SlotClk+ DLActive+ BWMgmt+ ABWMgmt-
SltCap: AttnBtn- PwrCtrl- MRL- AttnInd- PwrInd- HotPlug+ Surprise+
Slot #0, PowerLimit 10.000W; 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-
RootCap: CRSVisible-
RootCtl: ErrCorrectable- ErrNon-Fatal- ErrFatal- PMEIntEna- CRSVisible-
RootSta: PME ReqID 0000, PMEStatus- PMEPending-
DevCap2: Completion Timeout: Range BC, TimeoutDis+ NROPrPrP- LTR-
10BitTagComp- 10BitTagReq- OBFF Not Supported, ExtFmt- EETLPPrefix- EmergencyPowerReduction Not Supported, EmergencyPowerReductionInit-
FRS- LN System CLS Not Supported, TPHComp- ExtTPHComp- ARIFwd-
AtomicOpsCap: Routing- 32bit- 64bit- 128bitCAS-
DevCtl2: Completion Timeout: 50us to 50ms, TimeoutDis- LTR- OBFF Disabled, ARIFwd-
AtomicOpsCtl: ReqEn- EgressBlck-
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-
Retimer- 2Retimers- CrosslinkRes: unsupported
Capabilities: [80] MSI: Enable- Count=1/1 Maskable- 64bit-
Address: 00000000 Data: 0000
Capabilities: [90] Subsystem: Lenovo 7 Series/C216 Chipset Family PCI Express Root Port 1
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-
Kernel driver in use: pcieport

00:1c.1 PCI bridge: Intel Corporation 7 Series/C210 Series Chipset Family PCI Express Root Port 2 (rev c4) (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
Interrupt: pin B routed to IRQ 17
Bus: primary=00, secondary=03, subordinate=03, sec-latency=0
I/O behind bridge: [disabled]
Memory behind bridge: f0c00000-f0cfffff [size=1M]
Prefetchable memory behind bridge: [disabled]
Secondary status: 66MHz- FastB2B- ParErr- DEVSEL=fast >TAbort- <TAbort- <MAbort- <SERR- <PERR-
BridgeCtl: Parity- SERR+ NoISA- VGA- VGA16- MAbort- >Reset- FastB2B-
PriDiscTmr- SecDiscTmr- DiscTmrStat- DiscTmrSERREn-
Capabilities: [40] Express (v2) Root Port (Slot+), MSI 00
DevCap: MaxPayload 128 bytes, PhantFunc 0
ExtTag- RBE+
DevCtl: CorrErr- NonFatalErr- FatalErr- UnsupReq-
RlxdOrd- ExtTag- PhantFunc- AuxPwr- NoSnoop-
MaxPayload 128 bytes, MaxReadReq 128 bytes
DevSta: CorrErr- NonFatalErr- FatalErr- UnsupReq- AuxPwr+ TransPend-
LnkCap: Port #2, Speed 5GT/s, Width x1, ASPM L0s L1, Exit Latency L0s <512ns, L1 <16us
ClockPM- Surprise- LLActRep+ BwNot- ASPMOptComp-
LnkCtl: ASPM L1 Enabled; RCB 64 bytes, Disabled- CommClk+
ExtSynch- ClockPM- AutWidDis- BWInt- AutBWInt-
LnkSta: Speed 2.5GT/s (downgraded), Width x1 (ok)
TrErr- Train- SlotClk+ DLActive+ BWMgmt+ ABWMgmt-
SltCap: AttnBtn- PwrCtrl- MRL- AttnInd- PwrInd- HotPlug- Surprise-
Slot #1, PowerLimit 10.000W; 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+
RootCap: CRSVisible-
RootCtl: ErrCorrectable- ErrNon-Fatal- ErrFatal- PMEIntEna- CRSVisible-
RootSta: PME ReqID 0000, PMEStatus- PMEPending-
DevCap2: Completion Timeout: Range BC, TimeoutDis+ NROPrPrP- LTR-
10BitTagComp- 10BitTagReq- OBFF Not Supported, ExtFmt- EETLPPrefix- EmergencyPowerReduction Not Supported, EmergencyPowerReductionInit-
FRS- LN System CLS Not Supported, TPHComp- ExtTPHComp- ARIFwd-
AtomicOpsCap: Routing- 32bit- 64bit- 128bitCAS-
DevCtl2: Completion Timeout: 50us to 50ms, TimeoutDis- LTR- OBFF Disabled, ARIFwd-
AtomicOpsCtl: ReqEn- EgressBlck-
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-
Retimer- 2Retimers- CrosslinkRes: unsupported
Capabilities: [80] MSI: Enable- Count=1/1 Maskable- 64bit-
Address: 00000000 Data: 0000
Capabilities: [90] Subsystem: Lenovo 7 Series/C210 Series Chipset Family PCI Express Root Port 2
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-
Kernel driver in use: pcieport

00:1d.0 USB controller: Intel Corporation 7 Series/C216 Chipset Family USB Enhanced Host Controller #1 (rev 04) (prog-if 20 [EHCI])
Subsystem: Lenovo 7 Series/C216 Chipset Family USB Enhanced Host Controller
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 0: Memory at f1519000 (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: D3 NoSoftRst- PME-Enable+ DSel=0 DScale=0 PME-
Capabilities: [58] Debug port: BAR=1 offset=00a0
Capabilities: [98] PCI Advanced Features
AFCap: TP+ FLR+
AFCtrl: FLR-
AFStatus: TP-
Kernel driver in use: ehci-pci
Kernel modules: ehci_pci

00:1f.0 ISA bridge: Intel Corporation QS77 Express Chipset LPC Controller (rev 04)
Subsystem: Lenovo QS77 Express Chipset LPC Controller
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 driver in use: lpc_ich
Kernel modules: lpc_ich

00:1f.2 SATA controller: Intel Corporation 7 Series Chipset Family 6-port SATA Controller [AHCI mode] (rev 04) (prog-if 01 [AHCI 1.0])

	Subsystem: Lenovo 7 Series Chipset Family 6-port SATA Controller [AHCI mode]
	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 24
	Region 0: I/O ports at 4088 [size=8]
	Region 1: I/O ports at 4094 [size=4]
	Region 2: I/O ports at 4080 [size=8]
	Region 3: I/O ports at 4090 [size=4]
	Region 4: I/O ports at 4060 [size=32]
	Region 5: Memory at f1518000 (32-bit, non-prefetchable) [size=2K]
	Capabilities: [80] MSI: Enable+ Count=1/1 Maskable- 64bit-
		Address: fee01004  Data: 0025
	Capabilities: [70] 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: [a8] SATA HBA v1.0 BAR4 Offset=00000004
	Capabilities: [b0] PCI Advanced Features
		AFCap: TP+ FLR+
		AFCtrl: FLR-
		AFStatus: TP-
	Kernel driver in use: ahci

00:1f.3 SMBus: Intel Corporation 7 Series/C216 Chipset Family SMBus Controller (rev 04)
Subsystem: Lenovo 7 Series/C216 Chipset Family SMBus Controller
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 C routed to IRQ 18
Region 0: Memory at f1514000 (64-bit, non-prefetchable) [size=256]
Region 4: I/O ports at efa0 [size=32]
Kernel driver in use: i801_smbus
Kernel modules: i2c_i801

02:00.0 System peripheral: Ricoh Co Ltd MMC/SD Host Controller (rev 07) (prog-if 01)
Subsystem: Lenovo MMC/SD Host Controller
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 16
Region 0: Memory at f0d00000 (32-bit, non-prefetchable) [size=256]
Capabilities: [50] MSI: Enable- Count=1/1 Maskable- 64bit+
Address: 0000000000000000 Data: 0000
Capabilities: [78] 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: [80] Express (v1) Endpoint, MSI 00
DevCap: MaxPayload 128 bytes, PhantFunc 0, Latency L0s unlimited, L1 unlimited
ExtTag- AttnBtn+ AttnInd+ PwrInd+ RBE+ FLReset- SlotPowerLimit 10.000W
DevCtl: CorrErr- NonFatalErr- FatalErr- UnsupReq-
RlxdOrd+ ExtTag- PhantFunc- AuxPwr- NoSnoop+
MaxPayload 128 bytes, MaxReadReq 512 bytes
DevSta: CorrErr+ NonFatalErr- FatalErr- UnsupReq+ AuxPwr- TransPend-
LnkCap: Port #1, Speed 2.5GT/s, Width x1, ASPM L0s L1, Exit Latency L0s <4us, L1 unlimited
ClockPM+ Surprise- LLActRep- BwNot- ASPMOptComp-
LnkCtl: ASPM L1 Enabled; RCB 64 bytes, Disabled- CommClk+
ExtSynch- ClockPM+ AutWidDis- BWInt- AutBWInt-
LnkSta: Speed 2.5GT/s (ok), Width x1 (ok)
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=ff
Status: NegoPending- InProgress-
Capabilities: [800 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- AdvNonFatalErr+
CEMsk: RxErr- BadTLP- BadDLLP- Rollover- Timeout- AdvNonFatalErr+
AERCap: First Error Pointer: 00, ECRCGenCap+ ECRCGenEn- ECRCChkCap+ ECRCChkEn-
MultHdrRecCap- MultHdrRecEn- TLPPfxPres- HdrLogCap-
HeaderLog: 00000000 00000000 00000000 00000000
Kernel driver in use: sdhci-pci
Kernel modules: sdhci_pci

03:00.0 Network controller: Intel Corporation Centrino Advanced-N 6205 [Taylor Peak] (rev 96)
Subsystem: Intel Corporation Centrino Advanced-N 6205 [Taylor Peak]
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 26
Region 0: Memory at f0c00000 (64-bit, non-prefetchable) [size=8K]
Capabilities: [c8] 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: [d0] MSI: Enable+ Count=1/1 Maskable- 64bit+
Address: 00000000fee01004 Data: 002a
Capabilities: [e0] Express (v1) Endpoint, MSI 00
DevCap: MaxPayload 128 bytes, PhantFunc 0, Latency L0s <512ns, L1 unlimited
ExtTag- AttnBtn- AttnInd- PwrInd- RBE+ FLReset+ SlotPowerLimit 0.000W
DevCtl: CorrErr- NonFatalErr- FatalErr- UnsupReq-
RlxdOrd+ ExtTag- PhantFunc- AuxPwr- NoSnoop+ FLReset-
MaxPayload 128 bytes, MaxReadReq 128 bytes
DevSta: CorrErr- NonFatalErr- FatalErr- UnsupReq- AuxPwr+ TransPend-
LnkCap: Port #0, Speed 2.5GT/s, Width x1, ASPM L0s L1, Exit Latency L0s <4us, L1 <32us
ClockPM+ Surprise- LLActRep- BwNot- ASPMOptComp-
LnkCtl: ASPM L1 Enabled; RCB 64 bytes, Disabled- CommClk+
ExtSynch- ClockPM+ AutWidDis- BWInt- AutBWInt-
LnkSta: Speed 2.5GT/s (ok), Width x1 (ok)
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- AdvNonFatalErr-
CEMsk: RxErr- BadTLP- BadDLLP- Rollover- Timeout- AdvNonFatalErr+
AERCap: First Error Pointer: 00, ECRCGenCap- ECRCGenEn- ECRCChkCap- ECRCChkEn-
MultHdrRecCap- MultHdrRecEn- TLPPfxPres- HdrLogCap-
HeaderLog: 00000000 00000000 00000000 00000000
Capabilities: [140 v1] Device Serial Number 84-3a-4b-ff-ff-46-a9-10
Kernel driver in use: iwlwifi
Kernel modules: iwlwifi

#3 lore raw

Hi Ville,

Thank you for letting us know, and sincere apologies for troubles!

[...]

Quoted 18 lines
Quoted 10 lines
Quoted 6 lines

The pci sysfs "rom" file has disappeared for VGA devices. Looks to be a regression from commit 527139d738d7 ("PCI/sysfs:
Convert "rom" to static attribute").

Some kind of ordering issue between the sysfs file creation vs. pci_fixup_video() perhaps?

Can you attach your complete "lspci -vv" output? Also, which is the default device? I think there's a "boot_vga" sysfs file that shows this. "find /sys -name boot_vga | xargs grep ."

All I have is Intel iGPUs so it's always 00:02.0.

$ cat /sys/bus/pci/devices/0000\:00\:02.0/boot_vga 
1
$ cat /sys/bus/pci/devices/0000\:00\:02.0/rom
cat: '/sys/bus/pci/devices/0000:00:02.0/rom': No such file or directory
Quoted 5 lines

I've attached the full lspci from my IVB laptop, but the problem happens on every machine (with an iGPU at least).

I presume with a discrete GPU it might not happen since they actually have a real ROM.

Admittedly, the automated testing I was running before the patch was released didn't catch this. I primarily focused on trying to catch the race condition related to the ROM attribute creation.

I need to look into how to properly address this problem as if we were to revert the ROM attribute changes, then we would introduce the race condition we've had back.

Again, apologies for troubles this caused!

Krzysztof

#4 lore raw
Quoted 33 lines · Krzysztof Wilczyński

Hi Ville,

Thank you for letting us know, and sincere apologies for troubles!

[...]

Quoted 18 lines
Quoted 10 lines
Quoted 6 lines

The pci sysfs "rom" file has disappeared for VGA devices. Looks to be a regression from commit 527139d738d7 ("PCI/sysfs:
Convert "rom" to static attribute").

Some kind of ordering issue between the sysfs file creation vs. pci_fixup_video() perhaps?

Can you attach your complete "lspci -vv" output? Also, which is the default device? I think there's a "boot_vga" sysfs file that shows this. "find /sys -name boot_vga | xargs grep ."

All I have is Intel iGPUs so it's always 00:02.0.

$ cat /sys/bus/pci/devices/0000\:00\:02.0/boot_vga 
1
$ cat /sys/bus/pci/devices/0000\:00\:02.0/rom
cat: '/sys/bus/pci/devices/0000:00:02.0/rom': No such file or directory
Quoted 5 lines

I've attached the full lspci from my IVB laptop, but the problem happens on every machine (with an iGPU at least).

I presume with a discrete GPU it might not happen since they actually have a real ROM.

Admittedly, the automated testing I was running before the patch was released didn't catch this. I primarily focused on trying to catch the race condition related to the ROM attribute creation.

Quoted 5 lines

I need to look into how to properly address this problem as if we were to revert the ROM attribute changes, then we would introduce the race condition we've had back.

Again, apologies for troubles this caused!

What's the status of this regression and getting it fixed? It looks like there was no progress for quite a while. Could anyone please provide a status update?

Ciao, Thorsten (wearing his 'Linux kernel regression tracker' hat)

P.S.: As a Linux kernel regression tracker I'm getting a lot of reports on my table. I can only look briefly into most of them. Unfortunately therefore I sometimes will get things wrong or miss something important. I hope that's not the case here; if you think it is, don't hesitate to tell me about it in a public reply, that's in everyone's interest.

BTW, I have no personal interest in this issue, which is tracked using regzbot, my Linux kernel regression tracking bot
(https://linux-regtracking.leemhuis.info/regzbot/). I'm only posting this mail to get things rolling again and hence don't need to be CC on all further activities wrt to this regression.

#regzbot poke

#5 lore raw
Quoted 38 lines · Thorsten Leemhuis
Quoted 37 lines · Krzysztof Wilczyński

Hi Ville,

Thank you for letting us know, and sincere apologies for troubles!

[...]

Quoted 18 lines
Quoted 10 lines
Quoted 6 lines

The pci sysfs "rom" file has disappeared for VGA devices. Looks to be a regression from commit 527139d738d7 ("PCI/sysfs:
Convert "rom" to static attribute").

Some kind of ordering issue between the sysfs file creation vs. pci_fixup_video() perhaps?

Can you attach your complete "lspci -vv" output? Also, which is the default device? I think there's a "boot_vga" sysfs file that shows this. "find /sys -name boot_vga | xargs grep ."

All I have is Intel iGPUs so it's always 00:02.0.

$ cat /sys/bus/pci/devices/0000\:00\:02.0/boot_vga 
1
$ cat /sys/bus/pci/devices/0000\:00\:02.0/rom
cat: '/sys/bus/pci/devices/0000:00:02.0/rom': No such file or directory
Quoted 5 lines

I've attached the full lspci from my IVB laptop, but the problem happens on every machine (with an iGPU at least).

I presume with a discrete GPU it might not happen since they actually have a real ROM.

Admittedly, the automated testing I was running before the patch was released didn't catch this. I primarily focused on trying to catch the race condition related to the ROM attribute creation.

I need to look into how to properly address this problem as if we were to revert the ROM attribute changes, then we would introduce the race condition we've had back.

Quoted 5 lines
Quoted 1 line

Again, apologies for troubles this caused!

What's the status of this regression and getting it fixed? It looks like there was no progress for quite a while. Could anyone please provide a status update?

What a coincidence. Krzysztof and I chatted about this yesterday. No progress to report yet, but we are working on it.

Bjorn

#6 lore raw
Quoted 39 lines · Bjorn Helgaas
Quoted 38 lines · Thorsten Leemhuis
Quoted 37 lines · Krzysztof Wilczyński

Hi Ville,

Thank you for letting us know, and sincere apologies for troubles!

[...]

Quoted 18 lines
Quoted 10 lines
Quoted 6 lines

The pci sysfs "rom" file has disappeared for VGA devices. Looks to be a regression from commit 527139d738d7 ("PCI/sysfs:
Convert "rom" to static attribute").

Some kind of ordering issue between the sysfs file creation vs. pci_fixup_video() perhaps?

Can you attach your complete "lspci -vv" output? Also, which is the default device? I think there's a "boot_vga" sysfs file that shows this. "find /sys -name boot_vga | xargs grep ."

All I have is Intel iGPUs so it's always 00:02.0.

$ cat /sys/bus/pci/devices/0000\:00\:02.0/boot_vga 
1
$ cat /sys/bus/pci/devices/0000\:00\:02.0/rom
cat: '/sys/bus/pci/devices/0000:00:02.0/rom': No such file or directory
Quoted 5 lines

I've attached the full lspci from my IVB laptop, but the problem happens on every machine (with an iGPU at least).

I presume with a discrete GPU it might not happen since they actually have a real ROM.

Admittedly, the automated testing I was running before the patch was released didn't catch this. I primarily focused on trying to catch the race condition related to the ROM attribute creation.

I need to look into how to properly address this problem as if we were to revert the ROM attribute changes, then we would introduce the race condition we've had back.

Quoted 8 lines
Quoted 5 lines
Quoted 1 line

Again, apologies for troubles this caused!

What's the status of this regression and getting it fixed? It looks like there was no progress for quite a while. Could anyone please provide a status update?

What a coincidence. Krzysztof and I chatted about this yesterday. No progress to report yet, but we are working on it.

Many thx for the update! Ciao, Thorsten

#7 lore raw
In reply to Ville Syrjälä
Quoted 20 lines · Ville Syrjälä
Quoted 11 lines · Bjorn Helgaas
Quoted 6 lines · Ville Syrjälä

The pci sysfs "rom" file has disappeared for VGA devices. Looks to be a regression from commit 527139d738d7 ("PCI/sysfs:
Convert "rom" to static attribute").

Some kind of ordering issue between the sysfs file creation vs. pci_fixup_video() perhaps?

Can you attach your complete "lspci -vv" output? Also, which is the default device? I think there's a "boot_vga" sysfs file that shows this. "find /sys -name boot_vga | xargs grep ."

All I have is Intel iGPUs so it's always 00:02.0.

$ cat /sys/bus/pci/devices/0000\:00\:02.0/boot_vga 
1
$ cat /sys/bus/pci/devices/0000\:00\:02.0/rom
cat: '/sys/bus/pci/devices/0000:00:02.0/rom': No such file or directory
Quoted 38 lines

I've attached the full lspci from my IVB laptop, but the problem happens on every machine (with an iGPU at least).

I presume with a discrete GPU it might not happen since they actually have a real ROM.

Quoted 32 lines

I think the relevant path is something like this:

acpi_pci_root_add

    pci_acpi_scan_root
      ...
        pci_scan_single_device
          pci_device_add
            device_add
              ...
                sysfs_create_groups
                  ...
                    if (grp->is_visible())
                      pci_dev_rom_attr_is_visible  # after 527139d738d7
                        if (pci_resource_len(pdev, PCI_ROM_RESOURCE))
                          ...
    pci_bus_add_devices
      pci_bus_add_device
        pci_fixup_device(pci_fixup_final)
          pci_fixup_video
            if (vga_default_device() ...)
              # update PCI_ROM_RESOURCE
        pci_create_sysfs_dev_files
          if (pci_resource_len(pdev, PCI_ROM_RESOURCE))
            sysfs_create_bin_file("rom")           # before 527139d738d7

Prior to 527139d738d7, we ran pci_fixup_video() in pci_bus_add_devices(). The vga_default_device() there might depend on the fact that we've discovered all the PCI devices.

After 527139d738d7, we create the "rom" file in pci_device_add(), which happens as we discover each device, so maybe we don't yet know which device is the default VGA device.

Thanks, Ville!

I think this is happening because the iGPU has no ROM BAR, so pci_resource_len(PCI_ROM_RESOURCE) is 0 when we run pci_dev_rom_attr_is_visible(). Prior to 527139d738d7, we also used pci_resource_len(PCI_ROM_RESOURCE), but pci_fixup_video() had been run, and it filled in the ROM resource with the shadow ROM start and size.

Can you collect the dmesg output with "pci=earlydump"? I think that will show zeros at PCI_ROM_ADDRESS for your 00:02.0 device.

And can you try the test patch below? I reproduced the problem in qemu by instrumenting to clear the VGA ROM BAR, and moving the pci_fixup_video() quirk earlier makes it run before pci_dev_rom_attr_is_visible(), which fixes the problem for me.

arch/x86/pci/fixup.c +2 -2
index 2edd86649468..615a76d70019 100644
@@ -353,8 +353,8 @@ static void pci_fixup_video(struct pci_dev *pdev)
 		}
 	}
 }
-DECLARE_PCI_FIXUP_CLASS_FINAL(PCI_ANY_ID, PCI_ANY_ID,
-				PCI_CLASS_DISPLAY_VGA, 8, pci_fixup_video);
+DECLARE_PCI_FIXUP_CLASS_HEADER(PCI_ANY_ID, PCI_ANY_ID,
+			       PCI_CLASS_DISPLAY_VGA, 8, pci_fixup_video);
 
 
 static const struct dmi_system_id msi_k8t_dmi_table[] = {
author Tested-by
#8 lore raw
Quoted 69 lines · Bjorn Helgaas
Quoted 20 lines · Ville Syrjälä
Quoted 11 lines · Bjorn Helgaas
Quoted 6 lines · Ville Syrjälä

The pci sysfs "rom" file has disappeared for VGA devices. Looks to be a regression from commit 527139d738d7 ("PCI/sysfs:
Convert "rom" to static attribute").

Some kind of ordering issue between the sysfs file creation vs. pci_fixup_video() perhaps?

Can you attach your complete "lspci -vv" output? Also, which is the default device? I think there's a "boot_vga" sysfs file that shows this. "find /sys -name boot_vga | xargs grep ."

All I have is Intel iGPUs so it's always 00:02.0.

$ cat /sys/bus/pci/devices/0000\:00\:02.0/boot_vga 
1
$ cat /sys/bus/pci/devices/0000\:00\:02.0/rom
cat: '/sys/bus/pci/devices/0000:00:02.0/rom': No such file or directory
Quoted 38 lines

I've attached the full lspci from my IVB laptop, but the problem happens on every machine (with an iGPU at least).

I presume with a discrete GPU it might not happen since they actually have a real ROM.

Quoted 32 lines

I think the relevant path is something like this:

acpi_pci_root_add

    pci_acpi_scan_root
      ...
        pci_scan_single_device
          pci_device_add
            device_add
              ...
                sysfs_create_groups
                  ...
                    if (grp->is_visible())
                      pci_dev_rom_attr_is_visible  # after 527139d738d7
                        if (pci_resource_len(pdev, PCI_ROM_RESOURCE))
                          ...
    pci_bus_add_devices
      pci_bus_add_device
        pci_fixup_device(pci_fixup_final)
          pci_fixup_video
            if (vga_default_device() ...)
              # update PCI_ROM_RESOURCE
        pci_create_sysfs_dev_files
          if (pci_resource_len(pdev, PCI_ROM_RESOURCE))
            sysfs_create_bin_file("rom")           # before 527139d738d7

Prior to 527139d738d7, we ran pci_fixup_video() in pci_bus_add_devices(). The vga_default_device() there might depend on the fact that we've discovered all the PCI devices.

After 527139d738d7, we create the "rom" file in pci_device_add(), which happens as we discover each device, so maybe we don't yet know which device is the default VGA device.

Thanks, Ville!

I think this is happening because the iGPU has no ROM BAR, so pci_resource_len(PCI_ROM_RESOURCE) is 0 when we run pci_dev_rom_attr_is_visible(). Prior to 527139d738d7, we also used pci_resource_len(PCI_ROM_RESOURCE), but pci_fixup_video() had been run, and it filled in the ROM resource with the shadow ROM start and size.

Quoted 2 lines

Can you collect the dmesg output with "pci=earlydump"? I think that will show zeros at PCI_ROM_ADDRESS for your 00:02.0 device.

Yeah no real ROM on these:
pci 0000:00:02.0: config space:
00000000: 86 80 26 01 07 00 90 00 09 00 00 03 00 00 00 00 00000010: 04 00 00 f0 00 00 00 00 0c 00 00 e0 00 00 00 00 00000020: 01 50 00 00 00 00 00 00 00 00 00 00 aa 17 da 21 00000030: 00 00 00 00 90 00 00 00 00 00 00 00 0b 01 00 00 00000040: 09 00 0c 01 9e 61 00 e2 90 00 08 14 00 00 00 00 00000050: 11 02 00 00 11 00 00 00 00 00 00 00 01 00 a0 db 00000060: 00 00 02 00 00 00 00 00 00 00 00 00 00 00 00 00 00000070: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00000080: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00000090: 05 d0 00 00 00 00 00 00 00 00 00 00 00 00 00 00 000000a0: 00 00 00 00 13 00 06 03 00 00 00 00 00 00 00 00 000000b0: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 000000c0: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 000000d0: 01 a4 22 00 00 00 00 00 00 00 00 00 00 00 00 00 000000e0: 00 00 00 00 00 00 00 00 00 80 00 00 00 00 00 00 000000f0: 00 00 00 00 00 00 00 00 00 00 06 00 18 60 ef da pci 0000:00:02.0: [8086:0126] type 00 class 0x030000 pci 0000:00:02.0: reg 0x10: [mem 0xf0000000-0xf03fffff 64bit] pci 0000:00:02.0: reg 0x18: [mem 0xe0000000-0xefffffff 64bit pref] pci 0000:00:02.0: reg 0x20: [io 0x5000-0x503f]

Quoted 11 lines

And can you try the test patch below? I reproduced the problem in qemu by instrumenting to clear the VGA ROM BAR, and moving the pci_fixup_video() quirk earlier makes it run before pci_dev_rom_attr_is_visible(), which fixes the problem for me.

arch/x86/pci/fixup.c +0 -0
index 2edd86649468..615a76d70019 100644

arch/x86/pci/fixup.c static void pci_fixup_video(struct pci_dev *pdev) · line 360

Quoted 10 lines
arch/x86/pci/fixup.c +2 -2
@@ -353,8 +353,8 @@ static void pci_fixup_video(struct pci_dev *pdev)
 		}
 	}
 }
-DECLARE_PCI_FIXUP_CLASS_FINAL(PCI_ANY_ID, PCI_ANY_ID,
-				PCI_CLASS_DISPLAY_VGA, 8, pci_fixup_video);
+DECLARE_PCI_FIXUP_CLASS_HEADER(PCI_ANY_ID, PCI_ANY_ID,
+			       PCI_CLASS_DISPLAY_VGA, 8, pci_fixup_video);
 
 
 static const struct dmi_system_id msi_k8t_dmi_table[] = {

pci=earlydump now reports:
pci 0000:00:02.0: Video device with shadowed ROM at [mem 0x000c0000-0x000dffff]
and poking it via sysfs works fine.

Tested-by Ville Syrjälä <[email protected]>
Signature · 2 lines
Ville Syrjälä
Intel
#9 lore raw
In reply to Ville Syrjälä
Quoted 8 lines · Ville Syrjälä

Hi,

The pci sysfs "rom" file has disappeared for VGA devices. Looks to be a regression from commit 527139d738d7 ("PCI/sysfs:
Convert "rom" to static attribute").

Some kind of ordering issue between the sysfs file creation vs. pci_fixup_video() perhaps?

[TLDR: adding this regression to regzbot; most text you find below is compiled from a few templates paragraphs some of you might have seen already.]

Hi, this is your Linux kernel regression tracker speaking.

Thanks for the report.

Adding the regression mailing list to the list of recipients, as it should be in the loop for all regressions, as explained here:
https://www.kernel.org/doc/html/latest/admin-guide/reporting-issues.html

To be sure this issue doesn't fall through the cracks unnoticed, I'm adding it to regzbot, my Linux kernel regression tracking bot:

#regzbot ^introduced 527139d738d7
#regzbot title pci: the pci sysfs "rom" file has disappeared for VGA devices #regzbot ignore-activity

Reminder: when fixing the issue, please add a 'Link:' tag with the URL to the report (the parent of this mail), as explained in 'Documentaiton/process/submitting-patches.rst'. Regzbot then will automatically mark the regression as resolved once the fix lands in the appropriate tree. For more details about regzbot see footer.

Sending this to everyone that got the initial report, to make all aware of the tracking. I also hope that messages like this motivate people to directly get at least the regression mailing list and ideally even regzbot involved when dealing with regressions, as messages like this wouldn't be needed then.

Don't worry, I'll send further messages wrt to this regression just to the lists (with a tag in the subject so people can filter them away), as long as they are intended just for regzbot. With a bit of luck no such messages will be needed anyway.

Ciao, Thorsten (wearing his 'Linux kernel regression tracker' hat).

P.S.: As a Linux kernel regression tracker I'm getting a lot of reports on my table. I can only look briefly into most of them. Unfortunately therefore I sometimes will get things wrong or miss something important. I hope that's not the case here; if you think it is, don't hesitate to tell me about it in a public reply. That's in everyone's interest, as what I wrote above might be misleading to everyone reading this; any suggestion I gave thus might sent someone reading this down the wrong rabbit hole, which none of us wants.

BTW, I have no personal interest in this issue, which is tracked using regzbot, my Linux kernel regression tracking bot
(https://linux-regtracking.leemhuis.info/regzbot/). I'm only posting this mail to get things rolling again and hence don't need to be CC on all further activities wrt to this regression.

---
Additional information about regzbot:

If you want to know more about regzbot, check out its web-interface, the getting start guide, and/or the references documentation:

https://linux-regtracking.leemhuis.info/regzbot/
https://gitlab.com/knurd42/regzbot/-/blob/main/docs/getting_started.md
https://gitlab.com/knurd42/regzbot/-/blob/main/docs/reference.md

The last two documents will explain how you can interact with regzbot yourself if your want to.

Hint for reporters: when reporting a regression it's in your interest to tell #regzbot about it in the report, as that will ensure the regression gets on the radar of regzbot and the regression tracker. That's in your interest, as they will make sure the report won't fall through the cracks unnoticed.

Hint for developers: you normally don't need to care about regzbot once it's involved. Fix the issue as you normally would, just remember to include a 'Link:' tag to the report in the commit message, as explained in Documentation/process/submitting-patches.rst
That aspect was recently was made more explicit in commit 1f57bd42b77c:
https://git.kernel.org/linus/1f57bd42b77c