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7.260. usbredir

Updated usbredir packages that fix several bugs and add various enhancements are now available for Red Hat Enterprise Linux 6.
The usbredir packages provide a protocol for redirection of USB traffic from a single USB device to a different virtual machine then the one to which the USB device is attached. The usbredir packages contain a number of libraries to help implement support for usbredir.


The usbredir packages have been upgraded to upstream version 0.5.1, which provides a number of bug fixes and enhancements over the previous version. (BZ#842356)

Bug Fixes

Due to a bug in the libusbredirhost library, handling of timeouts for bulk transfers did not work correctly. Consequently, traffic of USB ACM serial port devices, such as PSTN modems and SmartCard readers, could not be properly redirected. With this update, no timeout is set on the usb-host side for these devices and the traffic redirection works as expected.
The usbredir code was allocating an unlimited amount of write buffers. Consequently, when a USB webcam produced data faster then it could be written out, the write queue grew boundlessly and the remote-viewer utility used an enormous amount of RAM. The underlying source code has been modified so that usbredir now checks how large the write queue is and drops isochronous data packets when the queue is too long.


Support for live migration of SPICE USB redirection requires support for state serialization. This update adds this missing support to the libusbredirparser library.
All users of usbredir are advised to upgrade to these updated packages, which fix these bugs and add these enhancements.