Am Montag, den 06.12.2010, 22:15 -0700 schrieb Bjorn Helgaas:
quoted text
> In addition to the isolation ideas I suggested above, you might
> boot with "maxcpus=1" and turn on all the Kconfig memory debug
> switches.

Booting with mminit_loglevel=4 maxcpus=1 causes this to show up:

[   17.364026] usb 1-6: device descriptor read/64, error -110
[   32.579024] usb 1-6: device descriptor read/64, error -110
[   32.794012] usb 1-6: new high speed USB device using ehci_hcd and address 6
[   47.907019] usb 1-6: device descriptor read/64, error -110
[   63.121019] usb 1-6: device descriptor read/64, error -110
[   63.335022] usb 1-6: new high speed USB device using ehci_hcd and address 7
[   73.748031] usb 1-6: device not accepting address 7, error -110
[   73.861018] usb 1-6: new high speed USB device using ehci_hcd and address 8
[   84.274018] usb 1-6: device not accepting address 8, error -110
[   84.285143] hub 1-0:1.0: unable to enumerate USB device on port 6

I have nothing connected to 1-6:

Bus 005 Device 001: ID 1d6b:0001 Linux Foundation 1.1 root hub
Bus 004 Device 003: ID 046d:c20a Logitech, Inc. WingMan RumblePad
Bus 004 Device 002: ID 03eb:3301 Atmel Corp. at43301 4-Port Hub
Bus 004 Device 001: ID 1d6b:0001 Linux Foundation 1.1 root hub
Bus 003 Device 001: ID 1d6b:0001 Linux Foundation 1.1 root hub
Bus 002 Device 003: ID 046d:c062 Logitech, Inc. 
Bus 002 Device 002: ID 413c:2105 Dell Computer Corp. Model L100 Keyboard
Bus 002 Device 001: ID 1d6b:0001 Linux Foundation 1.1 root hub
Bus 001 Device 005: ID 0dda:2026 Integrated Circuit Solution, Inc. USB2.0 Card Reader
Bus 001 Device 001: ID 1d6b:0002 Linux Foundation 2.0 root hub

It shows up at the same time as the crash happens without maxcpus.
However SysRq does work in this case.

-Tobias

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