The --tty option allows the redirection of a console (serial or virtio) to a pseudo-terminal. As long as the slave port of this pseudo-terminal is not opened by another process, a poll() call on the master port will return POLLHUP in the .event field. This confuses the virtio console code, as term_readable() returns a positive value, indicating that something is available, while the call to term_getc_iov will fail. The fix is to check for the presence of the POLLIN flag in the .event field. Note that this is only a partial fix, as kvmtool will still consume vast amounts of CPU resource by spinning like crazy until the slave port is actually opened. Signed-off-by: Marc Zyngier <marc.zyngier@xxxxxxx> --- tools/kvm/term.c | 4 +++- 1 file changed, 3 insertions(+), 1 deletion(-) diff --git a/tools/kvm/term.c b/tools/kvm/term.c index 5c3e543..214f5e2 100644 --- a/tools/kvm/term.c +++ b/tools/kvm/term.c @@ -89,8 +89,10 @@ bool term_readable(int term) .events = POLLIN, .revents = 0, }; + int err; - return poll(&pollfd, 1, 0) > 0; + err = poll(&pollfd, 1, 0); + return (err > 0 && (pollfd.revents & POLLIN)); } static void *term_poll_thread_loop(void *param) -- 1.8.3.4 -- To unsubscribe from this list: send the line "unsubscribe kvm" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
