Epson V500 USB BOGUS urb flags Windows VM with kernel 3.14.4-100 f19
After install of Fedora f19 kernel 3.14.4-100.fc19.x86_64 in late May, a Windows 2000 virtual machine under VirtualBox 4.3.12 r93733 running support software for a USB Epson V500 scanner has started to get continuous (about 2 per second) kernel WARNING messages indicating a problem with "BOGUS urb flags" from usb_submit_urb: "WARNING: CPU: 0 PID: 16621 at drivers/usb/core/urb.c:476 usb_submit_urb+0x28d/0x5c0() ... BOGUS urb flags, 1 --> 0"
This happens as long as the VM is up and the V500 scanner is powered-up and connected to the VM once the USB has first been recognized by WIN2K and the device driver installed even when both WIN2K and the scanner are sitting idle (device driver dependency from a re-install of the software in a cloned machine). The original VM with the problem had been running for several years under different releases of Fedora and different releases of VirtualBox with no problem.
Temporarily reverting to my previous kernel 3.13.11-100.fc19.x86_64 causes the problem to disappear (for both of the previously mentioned VirtualBox releases).
I reported the problem to Fedora bugzilla, but since I can only recreate the problem using a VirtualBox VM, got predictable response that it is a problem with VirtualBox drivers even though a kernel change started the symptoms. Subsequent testing shows V500 scanner hardware works without any logged warnings, both from "iscan" native Linux scanner package and from a just-built Windows 2000 QEMU/KVM virtual machine running the same Windows software as on the VirtualBox Win2K VM. Circumstantial evidence would appear to point to some kind of VirtualBox incompatibility with the recent 3.14.4-100 kernel.