Adjunct is the output of dmidecode (: I didn't try setting "try_handoff" to 0, but I think behavior is predictable since in that case the kernel will never reach the pci_write in question. I found a kernel compiling option named "Enable PCI quirk workarounds". It seems what i've been looking for (i mean, disabling of it), at least while i have this buggy bios... 2014-05-29 11:46 GMT-03:00 Alan Stern <stern@xxxxxxxxxxxxxxxxxxx>: > On Wed, 28 May 2014, Leandro Liptak wrote: > >> > If you comment out the pci_write and plug in a USB device, like a flash >> > drive, does it work okay? >> > >> > Have you checked for any BIOS updates available from the manufacturer? >> > This really sounds like a bug in the BIOS. >> >> Yes, any plugged USB device seems to work ok! I didn't find any BIOS >> update.. So I don't know if this line of code is really necessary at >> all, perhaps it could be a configuration option at kernel compilation >> time (?) > > It really is necessary. It is documented in section 5.1 of the EHCI > specification. If your computer hangs then your computer is not > compliant with the spec. This is undoubtedly caused by a BIOS bug. > > What happens if you initialize try_handoff (at the start of the > functionn) to 0 instead of 1, and leave the pci_write unchanged? > > Also, can you post the output from dmidecode? > > Alan Stern >
# dmidecode 2.11 SMBIOS 2.6 present. 36 structures occupying 1377 bytes. Table at 0x000DC010. Handle 0x0000, DMI type 0, 24 bytes BIOS Information Vendor: Phoenix Technologies LTD Version: 6.00 Release Date: 03/22/2011 Address: 0xE8000 Runtime Size: 96 kB ROM Size: 1024 kB Characteristics: ISA is supported PCI is supported PNP is supported BIOS is upgradeable BIOS shadowing is allowed ESCD support is available Boot from CD is supported Selectable boot is supported BIOS ROM is socketed EDD is supported Print screen service is supported (int 5h) 8042 keyboard services are supported (int 9h) Serial services are supported (int 14h) Printer services are supported (int 17h) CGA/mono video services are supported (int 10h) USB legacy is supported Smart battery is supported BIOS boot specification is supported Targeted content distribution is supported Handle 0x0001, DMI type 1, 27 bytes System Information Manufacturer: HASEE Product Name: E200 Version: Revision A Serial Number: 0123456789 UUID: Not Present Wake-up Type: Power Switch SKU Number: 1234567890 Family: 1234567890 Handle 0x0002, DMI type 2, 17 bytes Base Board Information Manufacturer: HASEE Product Name: E210 Version: Revision B Serial Number: 400 Asset Tag: PTL Nanjing Features: Board is a hosting board Board is replaceable Location In Chassis: Not Applicable Chassis Handle: 0x0003 Type: Motherboard Contained Object Handles: 1 0x0000 Handle 0x0003, DMI type 3, 21 bytes Chassis Information Manufacturer: No Enclosure Type: Other Lock: Not Present Version: N/A Serial Number: None Asset Tag: No Asset Tag Boot-up State: Safe Power Supply State: Safe Thermal State: Safe Security Status: None OEM Information: 0x00001234 Height: Unspecified Number Of Power Cords: Unspecified Contained Elements: 0 Handle 0x0004, DMI type 4, 42 bytes Processor Information Socket Designation: CPU 1 Type: Central Processor Family: Other Manufacturer: Intel ID: CA 06 01 00 FF FB EB BF Version: C1 Voltage: 1.8 V External Clock: 200 MHz Max Speed: 1800 MHz Current Speed: 1800 MHz Status: Populated, Enabled Upgrade: Socket LGA775 L1 Cache Handle: 0x0005 L2 Cache Handle: 0x0006 L3 Cache Handle: Not Provided Serial Number: Not Specified Asset Tag: Not Specified Part Number: Not Specified Core Count: 2 Core Enabled: 2 Thread Count: 4 Characteristics: 64-bit capable Handle 0x0005, DMI type 7, 19 bytes Cache Information Socket Designation: L1 Cache Configuration: Enabled, Socketed, Level 1 Operational Mode: Write Back Location: Internal Installed Size: 24 kB Maximum Size: 24 kB Supported SRAM Types: Burst Pipeline Burst Asynchronous Installed SRAM Type: Asynchronous Speed: Unknown Error Correction Type: Single-bit ECC System Type: Data Associativity: Other Handle 0x0006, DMI type 7, 19 bytes Cache Information Socket Designation: L2 Cache Configuration: Enabled, Socketed, Level 2 Operational Mode: Write Back Location: Internal Installed Size: 512 kB Maximum Size: 512 kB Supported SRAM Types: Burst Pipeline Burst Asynchronous Installed SRAM Type: Burst Speed: Unknown Error Correction Type: Single-bit ECC System Type: Unified Associativity: 8-way Set-associative Handle 0x0007, DMI type 8, 9 bytes Port Connector Information Internal Reference Designator: J8A2 Internal Connector Type: 9 Pin Dual Inline (pin 10 cut) External Reference Designator: COM 1 External Connector Type: DB-9 male Port Type: Serial Port 16550A Compatible Handle 0x0008, DMI type 8, 9 bytes Port Connector Information Internal Reference Designator: J7A1 Internal Connector Type: None External Reference Designator: Keyboard External Connector Type: Circular DIN-8 male Port Type: Keyboard Port Handle 0x0009, DMI type 8, 9 bytes Port Connector Information Internal Reference Designator: J7A1 Internal Connector Type: None External Reference Designator: PS/2 Mouse External Connector Type: Circular DIN-8 male Port Type: Keyboard Port Handle 0x000A, DMI type 9, 17 bytes System Slot Information Designation: PCI Slot #1 - J1B1 Type: 32-bit PCI Current Usage: Available Length: Long ID: 2 Characteristics: 5.0 V is provided 3.3 V is provided Bus Address: 0000:11:00.0 Handle 0x000B, DMI type 9, 17 bytes System Slot Information Designation: PCIe Slot #1 - J2D1 Type: 32-bit PCI Express Current Usage: Available Length: Long ID: 10 Characteristics: 5.0 V is provided 3.3 V is provided Bus Address: 0000:16:00.0 Handle 0x000C, DMI type 9, 17 bytes System Slot Information Designation: PCIe Slot #2 - J2C1 Type: 32-bit PCI Express Current Usage: Available Length: Long ID: 9 Characteristics: 5.0 V is provided 3.3 V is provided Bus Address: 0000:15:00.0 Handle 0x000D, DMI type 9, 17 bytes System Slot Information Designation: PCIe Slot #3 - J3C1 Type: 32-bit PCI Express Current Usage: In Use Length: Long ID: 8 Characteristics: 5.0 V is provided 3.3 V is provided Bus Address: 0000:14:00.0 Handle 0x000E, DMI type 9, 17 bytes System Slot Information Designation: PCIe Slot #4 - J4C1 Type: 32-bit PCI Express Current Usage: In Use Length: Long ID: 7 Characteristics: 5.0 V is provided 3.3 V is provided Bus Address: 0000:13:00.0 Handle 0x000F, DMI type 10, 6 bytes On Board Device Information Type: Sound Status: Disabled Description: ADI1886 Handle 0x0010, DMI type 11, 5 bytes OEM Strings String 1: This is the Intel x35 String 2: Customer Reference Board Handle 0x0011, DMI type 12, 5 bytes System Configuration Options Option 1: Jumper settings can be described here. Handle 0x0012, DMI type 15, 29 bytes System Event Log Area Length: 64 bytes Header Start Offset: 0x0000 Header Length: 16 bytes Data Start Offset: 0x0010 Access Method: General-purpose non-volatile data functions Access Address: 0x0000 Status: Valid, Not Full Change Token: 0x0000001F Header Format: Type 1 Supported Log Type Descriptors: 3 Descriptor 1: POST error Data Format 1: POST results bitmap Descriptor 2: Single-bit ECC memory error Data Format 2: Multiple-event Descriptor 3: Multi-bit ECC memory error Data Format 3: Multiple-event Handle 0x0013, DMI type 16, 15 bytes Physical Memory Array Location: System Board Or Motherboard Use: System Memory Error Correction Type: None Maximum Capacity: 2 GB Error Information Handle: Not Provided Number Of Devices: 2 Handle 0x0014, DMI type 17, 28 bytes Memory Device Array Handle: 0x0013 Error Information Handle: Not Provided Total Width: 64 bits Data Width: 64 bits Size: 2048 MB Form Factor: SODIMM Set: 1 Locator: J6G1 Bank Locator: DIMM 0 Type: DDR3 Type Detail: Synchronous Speed: 800 MHz Manufacturer: 04CB Serial Number: 141B0000 Asset Tag: 1212 Part Number: AD73I1B0873EV Rank: Unknown Handle 0x0015, DMI type 17, 28 bytes Memory Device Array Handle: 0x0013 Error Information Handle: Not Provided Total Width: Unknown Data Width: Unknown Size: No Module Installed Form Factor: SODIMM Set: 1 Locator: J6G2 Bank Locator: DIMM 1 Type: DDR3 Type Detail: Synchronous Speed: 800 MHz Manufacturer: Serial Number: Asset Tag: Part Number: Rank: Unknown Handle 0x0016, DMI type 19, 15 bytes Memory Array Mapped Address Starting Address: 0x00000000000 Ending Address: 0x0007FFFFFFF Range Size: 2 GB Physical Array Handle: 0x0013 Partition Width: 2 Handle 0x0017, DMI type 20, 19 bytes Memory Device Mapped Address Starting Address: 0x00000000000 Ending Address: 0x0007FFFFFFF Range Size: 2 GB Physical Device Handle: 0x0014 Memory Array Mapped Address Handle: 0x0016 Partition Row Position: Unknown Interleave Position: Unknown Interleaved Data Depth: Unknown Handle 0x0018, DMI type 20, 19 bytes Memory Device Mapped Address Starting Address: 0x0007FFFFC00 Ending Address: 0x0007FFFFFFF Range Size: 1 kB Physical Device Handle: 0x0015 Memory Array Mapped Address Handle: 0x0016 Partition Row Position: Unknown Interleave Position: Unknown Interleaved Data Depth: Unknown Handle 0x0019, DMI type 23, 13 bytes System Reset Status: Enabled Watchdog Timer: Present Boot Option: Do Not Reboot Boot Option On Limit: Do Not Reboot Reset Count: Unknown Reset Limit: Unknown Timer Interval: Unknown Timeout: Unknown Handle 0x001A, DMI type 24, 5 bytes Hardware Security Power-On Password Status: Disabled Keyboard Password Status: Unknown Administrator Password Status: Disabled Front Panel Reset Status: Unknown Handle 0x001B, DMI type 25, 9 bytes System Power Controls Next Scheduled Power-on: 12-31 23:59:59 Handle 0x001C, DMI type 26, 20 bytes Voltage Probe Description: Voltage Probe Location: Processor Status: OK Maximum Value: Unknown Minimum Value: Unknown Resolution: Unknown Tolerance: Unknown Accuracy: Unknown OEM-specific Information: 0x00000000 Handle 0x001D, DMI type 27, 12 bytes Cooling Device Temperature Probe Handle: 0x001E Type: Fan Status: OK OEM-specific Information: 0x00000000 Handle 0x001E, DMI type 28, 20 bytes Temperature Probe Description: Temperature Probe Location: Processor Status: OK Maximum Value: Unknown Minimum Value: Unknown Resolution: Unknown Tolerance: Unknown Accuracy: Unknown OEM-specific Information: 0x00000000 Handle 0x001F, DMI type 29, 20 bytes Electrical Current Probe Description: Electrical Current Probe Location: Processor Status: OK Maximum Value: Unknown Minimum Value: Unknown Resolution: Unknown Tolerance: Unknown Accuracy: Unknown OEM-specific Information: 0x00000000 Handle 0x0020, DMI type 30, 6 bytes Out-of-band Remote Access Manufacturer Name: Intel Inbound Connection: Disabled Outbound Connection: Enabled Handle 0x0021, DMI type 32, 20 bytes System Boot Information Status: <OUT OF SPEC> Handle 0x0022, DMI type 126, 4 bytes Inactive Handle 0x0023, DMI type 127, 4 bytes End Of Table
