Am 25.02.2013 21:54, schrieb Alan Stern:
> Sarah (and anyone else who's interested):
>
> A while ago I wrote about a hardware bug in my Intel ICH5 and ICH8 EHCI
> controllers. You pointed out that these are rather old components, not
> being used in current systems, which is quite true.
>
> Now I have figured out a simple way for anyone to test for this bug in
> any EHCI controller, without the need for a g-zero gadget. It's a
> two-part procedure:
>
> Apply the patch below (which is written for vanilla 3.8) and
> load the resulting driver. The patch adds an explicit test
> to ehci-hcd for detecting the bug.
>
> Then plug in an ordinary USB flash drive and run the attached
> program (as root), giving it the device path for the flash
> drive as the single command-line argument. For example:
>
> sudo ./ehci-test /dev/bus/usb/002/003
>
> The program won't do anything bad to the flash drive; it just reads the
> first 256 KB of data over and over again, now and then unlinking an URB
> to try and trigger the bug. If the program works right, it will print
> out a loop counter every hundred iterations. If it runs for 1000
> iterations with no error messages in the kernel log, you may consider
> that the controller has passed the test. This should take under a
> minute, depending on the hardware speed.
>
> The program won't stop by itself unless something goes wrong. You can
> kill it with ^C or more simply by unplugging the flash drive. (If you
> want to be safe, make sure there are no mounted filesystems on the
> drive before running the test program.)
>
> If the hardware bug is detected, the kernel patch will print error
> messages to the system log. For example, when I run the test on the
> Intel controller in this computer, I get:
>
> [ 150.019441] usb-storage 3-8:1.0: disconnect by usbfs
> [ 150.271190] ehci-pci 0000:00:1d.7: EHCI hardware bug detected: 00008d00 80008d00
> [ 150.591089] ehci-pci 0000:00:1d.7: EHCI hardware bug detected: 00008d00 80008d00
> [ 151.538560] ehci-pci 0000:00:1d.7: EHCI hardware bug detected: 00008d00 80008d00
> [ 151.857569] ehci-pci 0000:00:1d.7: EHCI hardware bug detected: 00008d00 80008d00
> [ 152.018886] ehci-pci 0000:00:1d.7: EHCI hardware bug detected: 00008d00 80008d00
> [ 152.179810] ehci-pci 0000:00:1d.7: EHCI hardware bug detected: 80008d00 00008d00
> [ 153.211804] ehci-pci 0000:00:1d.7: EHCI hardware bug detected: 00008d00 80008d00
> [ 153.374497] ehci-pci 0000:00:1d.7: EHCI hardware bug detected: 00008d00 80008d00
> [ 153.770443] ehci-pci 0000:00:1d.7: EHCI hardware bug detected: 80008d00 00008d00
> [ 154.247861] ehci-pci 0000:00:1d.7: EHCI hardware bug detected: 82008d80 00008d00
> [ 154.566912] ehci-pci 0000:00:1d.7: EHCI hardware bug detected: 82008d80 00008d00
> [ 155.359101] ehci-pci 0000:00:1d.7: EHCI hardware bug detected: 00008d00 80008d00
> [ 155.838132] ehci-pci 0000:00:1d.7: EHCI hardware bug detected: 00008d00 80008d00
> [ 156.791107] ehci-pci 0000:00:1d.7: EHCI hardware bug detected: 80008d00 00008d00
> [ 157.267620] ehci-pci 0000:00:1d.7: EHCI hardware bug detected: 00008d00 80008d00
> [ 159.252057] ehci-pci 0000:00:1d.7: EHCI hardware bug detected: 80008d00 00008d00
> [ 159.886048] ehci-pci 0000:00:1d.7: EHCI hardware bug detected: 80008d00 00008d00
> [ 160.206625] ehci-pci 0000:00:1d.7: EHCI hardware bug detected: 02008d80 80008d00
> ...
>
> You get the idea. The values in the two columns on the right are
> always supposed to be equal; when they aren't it indicates that the
> controller has done a DMA write at a time when ehci-hcd isn't expecting
> one to happen.
>
> I'd be interested to hear the results of testing on a variety of
> controllers. (This computer also has an NEC EHCI controller, and that
> one does not have the bug.) Do the EHCI controllers on current Intel
> chipsets pass the test? What about other vendors?
>
> Thanks to all who try it out and report their results.
>
> Alan Stern
Here is the result of your test procedure (fix applied, running kernel
3.9-rc1) for the following device:
00:02.1 USB controller [0c03]: NVIDIA Corporation MCP61 USB 2.0
Controller [10de:03f2] (rev a2) (prog-if 20 [EHCI])
Subsystem: ASUSTeK Computer Inc. Device [1043:8234]
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 (750ns min, 250ns max)
Interrupt: pin B routed to IRQ 22
Region 0: Memory at fe02e000 (32-bit, non-prefetchable) [size=256]
Capabilities: [44] Debug port: BAR=1 offset=0098
Capabilities: [80] 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: ehci-pci
=> dmesg output:
[ 207.965961] ehci-pci 0000:00:02.1: EHCI hardware bug detected:
80008d00 00008d00
[ 208.020904] ehci-pci 0000:00:02.1: EHCI hardware bug detected:
82008d80 00008d00
[ 208.198698] ehci-pci 0000:00:02.1: EHCI hardware bug detected:
80008d00 00009d00
[ 208.201699] ehci-pci 0000:00:02.1: EHCI hardware bug detected:
82008d80 00009d00
[ 208.227968] ehci-pci 0000:00:02.1: EHCI hardware bug detected:
00008d00 80008d00
[ 208.230453] ehci-pci 0000:00:02.1: EHCI hardware bug detected:
80008d00 00008d00
[ 208.264518] ehci-pci 0000:00:02.1: EHCI hardware bug detected:
00008d00 80008d00
[ 208.287447] ehci-pci 0000:00:02.1: EHCI hardware bug detected:
02008d80 80008d00
[ 208.398602] ehci-pci 0000:00:02.1: EHCI hardware bug detected:
82008d80 00008d00
[ 208.406755] ehci-pci 0000:00:02.1: EHCI hardware bug detected:
80008d00 00008d00
[ 208.456527] ehci-pci 0000:00:02.1: EHCI hardware bug detected:
02008d80 80008d00
[ 208.460998] ehci-pci 0000:00:02.1: EHCI hardware bug detected:
80008d00 00009d00
[ 208.497597] ehci-pci 0000:00:02.1: EHCI hardware bug detected:
80008d00 00008d00
[ 208.556599] ehci-pci 0000:00:02.1: EHCI hardware bug detected:
82008d80 00008d00
[ 208.560598] ehci-pci 0000:00:02.1: EHCI hardware bug detected:
80008d00 00009d00
[ 208.563607] ehci-pci 0000:00:02.1: EHCI hardware bug detected:
82008d80 00008d00
[ 208.651304] ehci-pci 0000:00:02.1: EHCI hardware bug detected:
00008d00 80008d00
[ 208.692580] ehci-pci 0000:00:02.1: EHCI hardware bug detected:
82008d80 00008d00
[ 208.692936] ehci-pci 0000:00:02.1: EHCI hardware bug detected:
82008d80 00008d00
[ 208.788225] ehci-pci 0000:00:02.1: EHCI hardware bug detected:
80008d00 82008d80
[ 208.831607] ehci-pci 0000:00:02.1: EHCI hardware bug detected:
80008d00 00008d00
[ 208.851212] ehci-pci 0000:00:02.1: EHCI hardware bug detected:
80008d00 00008d00
[ 208.862448] ehci-pci 0000:00:02.1: EHCI hardware bug detected:
82008d80 00008d00
[ 208.919208] ehci-pci 0000:00:02.1: EHCI hardware bug detected:
02008d80 80009d00
[ 208.968208] ehci-pci 0000:00:02.1: EHCI hardware bug detected:
82008d80 00009d00
[ 208.980844] ehci-pci 0000:00:02.1: EHCI hardware bug detected:
02008d80 80008d00
[ 209.138456] ehci-pci 0000:00:02.1: EHCI hardware bug detected:
82008d80 00008d00
Regards,
Frank
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