From 9e5a25f1c209ff51e4b65124a3b76dd3f1b0fb49 Mon Sep 17 00:00:00 2001 From: =?UTF-8?q?Marc-Andr=C3=A9=20Lureau?= Date: Fri, 10 Oct 2014 19:05:11 +0200 Subject: qxl: keep going if reaching guest bug on empty area Xorg server hangs when using xfig and typing a text with space: #0 qxl_wait_for_io_command (qxl=) at qxl_io.c:47 #1 0x00007f826a49a299 in qxl_download_box (surface=0x221d030, x1=231, y1=259, x2=, y2=) at qxl_surface.c:143 while (!(ram_header->int_pending & QXL_INTERRUPT_IO_CMD)) usleep (1); The QXL driver is calling QXL_IO_UPDATE_AREA with an empty area. This is a guest bug. The call is async and no ack is sent back on guest bug, so the X server will hang. The driver should be improved to avoid this situation and also to abort on QXL_INTERRUPT_ERROR. This will be a different patch series for the driver. However, it is simple enough to keep qemu running on empty areas update, which is what this patch provides. https://bugzilla.redhat.com/show_bug.cgi?id=1151363 Signed-off-by: Gerd Hoffmann --- hw/display/qxl.c | 5 +++++ 1 file changed, 5 insertions(+) diff --git a/hw/display/qxl.c b/hw/display/qxl.c index 93b3518b21..b540dd656c 100644 --- a/hw/display/qxl.c +++ b/hw/display/qxl.c @@ -1591,6 +1591,11 @@ async_common: qxl_set_guest_bug(d, "QXL_IO_UPDATE_AREA: invalid area (%ux%u)x(%ux%u)\n", update.left, update.top, update.right, update.bottom); + if (update.left == update.right || update.top == update.bottom) { + /* old drivers may provide empty area, keep going */ + qxl_clear_guest_bug(d); + goto cancel_async; + } break; } if (async == QXL_ASYNC) { -- cgit v1.2.1