And with verbose logging (level 8).

[...]
|dfbf9000| USB MSC vendor='WD' product='Elements 10B8' rev='1012' type=0 removable=0
|dfbf9000| scsi_is_ready (drive=0x000f5c40)
|dfbf9000| ehci_send_pipe qh=0x0009ed80 dir=0 data=0xdfbf9e45 size=31
|dfbfe000| ehci_send_pipe qh=0x0009ef00 dir=128 data=0xdfbfeed2 size=18
|dfbf9000| ehci_send_pipe qh=0x0009ee00 dir=128 data=0xdfbf9e38 size=13
|dfbfe000| ehci_send_pipe qh=0x0009ef00 dir=128 data=0xdfbfee38 size=13
|dfbf9000| ehci_send_pipe qh=0x0009ed80 dir=0 data=0xdfbf9e45 size=31
|dfbfe000| Device reports MEDIUM NOT PRESENT
|dfbfe000| scsi_is_ready returned -1
|dfbfe000| Unable to configure USB MSC drive.
|dfbfe000| phys_free f5c70 (detail=0xdfc08fe0)
|dfbfe000| Unable to configure USB MSC device.
|dfbfe000| phys_free dfc090f0 (detail=0xdfc090c0)
|dfbfe000| phys_free dfc05400 (detail=0xdfc04e40)
\dfbfe000/ End thread
phys_free dfbfe000 (detail=0xdfc04e10)
|dfbf9000| ehci_send_pipe qh=0x0009ee00 dir=128 data=0xdfbf9ed2 size=18
|dfc02000| ehci_free_pipes 0xdfc057b0
|dfbf9000| ehci_send_pipe qh=0x0009ee00 dir=128 data=0xdfbf9e38 size=13
|dfc02000| phys_free dfc08f00 (detail=0xdfc08f70)
|dfc02000| phys_free 9ee80 (detail=0xdfc09060)
|dfc02000| phys_free 9ef00 (detail=0xdfc09090)
Wcall16 with invalid stack
[hangs here]


On Wed, Dec 23, 2015 at 4:05 PM, Tobias Diedrich <tobiasdiedrich@gmail.com> wrote:
Hi,

I've attached a WD Elements 2TB drive to my pcengines APU1 as external storage and just found that with the disk attached SeaBIOS crashes on boot. :/
The controller is USB2, not USB3.

Both the stock rom "Build 4/5/2014 (current production)" and a self-compiled coreboot rom with SeaBIOS master from git (rel-1.9.0-43-g76327b9) exhibit the same issue.

I'm not sure if http://www.seabios.org/pipermail/seabios/2015-November/009910.html is the same issue since it doesn't have log messages and doesn't seem to complain about it not booting at all. 

Cheers,
Tobias