If a PXE client only wants to find out the size of a file, it will
open the file and then abort the transfer by sending a TFTP ERROR packet.
The ERROR packet should cause qemu to terminate the session. If not,
the sessions will soon run out and cause timeouts in the client.
Also, if a TFTP session already exists with same IP/UDP port, it
should be terminated when a new RRQ is received, instead of creating a
duplicate (which will never be used).
A patch for gPXE to send the ERROR packet is also being submitted to
gPXE. Together they resolve slowness/hanging when booting pxegrub from
qemu's internal TFTP server. The patch from Milan Plzik to return
after sending OACK is also required for a complete fix.
Signed-off-by: Thomas Horsten <thomas@horsten.com>
Signed-off-by: Milan Plzik <milan.plzik@gmail.com>
Signed-off-by: Anthony Liguori <aliguori@us.ibm.com>
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