Red Hat Bugzilla – Bug 797854
host can't receive characters if disconnect to TCP socket then re-connect again
Last modified: 2014-07-21 08:54:23 EDT
Description of problem: boot a guest with TCP socket backend, transmit characters from guest to host via port, host could receive characters. Disconnect netcat in host by ctrl-c, re-connect again, transmit again from guest, host can't receive characters. *Re-send* in guest, host receives the characters. Version-Release number of selected component (if applicable): host: # rpm -q qemu-kvm;uname -r qemu-kvm-0.12.1.2-2.231.el6.x86_64 2.6.32-235.el6.x86_64 guest: 2.6.32-236.el6.x86_64 How reproducible: 100% Steps to Reproduce: 1. boot with tcp socket as backend: -chardev socket,id=charchannel1,host=127.0.0.1,port=5555,server,nowait -device virtserialport,bus=virtio-serial0.0,chardev=charchannel1,id=channel1,name=tcp.com.redhat.rhevm.vdsm # cat /sys/kernel/debug/virtio-ports/vport0p2 name: tcp.com.redhat.rhevm.vdsm guest_connected: 0 host_connected: 0 outvq_full: 0 bytes_sent: 0 bytes_received: 0 bytes_discarded: 0 is_console: no console_vtermno: 2185810413 2. nc 127.0.0.1 5555 # cat /sys/kernel/debug/virtio-ports/vport0p2 name: tcp.com.redhat.rhevm.vdsm guest_connected: 0 host_connected: 1 outvq_full: 0 bytes_sent: 0 bytes_received: 0 bytes_discarded: 0 is_console: no console_vtermno: 2185810413 3.# echo aaaa > /dev/vport0p2 # cat /sys/kernel/debug/virtio-ports/vport0p2 name: tcp.com.redhat.rhevm.vdsm guest_connected: 0 host_connected: 1 outvq_full: 0 bytes_sent: 5 bytes_received: 0 bytes_discarded: 0 is_console: no console_vtermno: 2185810413 4.Ctrl-c in host # cat /sys/kernel/debug/virtio-ports/vport0p2 name: tcp.com.redhat.rhevm.vdsm guest_connected: 0 host_connected: 1 <----- expected? outvq_full: 0 bytes_sent: 5 bytes_received: 0 bytes_discarded: 0 is_console: no console_vtermno: 2185810413 5.re-connect by nc 127.0.0.1 5555 6.# echo aaaa > /dev/vport0p2 # cat /sys/kernel/debug/virtio-ports/vport0p2 name: tcp.com.redhat.rhevm.vdsm guest_connected: 0 host_connected: 1 outvq_full: 0 bytes_sent: 10 bytes_received: 0 bytes_discarded: 0 is_console: no console_vtermno: 2185810413 Actual results: after step 3, host can receive characters after step 6, host fails to receive characters for the first time transmission, re-send for the second time, host could receive. Expected results: Additional info:
This request was not resolved in time for the current release. Red Hat invites you to ask your support representative to propose this request, if still desired, for consideration in the next release of Red Hat Enterprise Linux.
This request was erroneously removed from consideration in Red Hat Enterprise Linux 6.4, which is currently under development. This request will be evaluated for inclusion in Red Hat Enterprise Linux 6.4.
One of the several bugs that need a rewrite of the qemu chardev layer. Moving to RHEL7.
*** This bug has been marked as a duplicate of bug 702271 ***