fix: make graphical VMs usable with a mouse - #29
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A window or VNC VM had only qemu's default relative PS/2 mouse. A desktop guest cannot align its cursor to the host cursor from relative deltas, so the pointer drifted and clicks in XFCE landed off target. usb-tablet reports absolute coordinates, so the guest cursor tracks the host cursor in the gtk window and in a VNC client. qemu-xhci gives it a USB bus; the default pc machine has none.
Alpine boots mdev, which never feeds Xorg its input devices, so libinput found no mouse or keyboard and the desktop ignored every click. The tablet device existed but no driver bound it. setup-devd udev makes eudev the device manager and adds udev-trigger and udev-settle to sysinit. A cold-plug then hands the current devices to the live session that starts X now, before the next boot's trigger runs. Ubuntu, Debian, and Arch already run udev under systemd, so only the Alpine script needs this.
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A provisioned XFCE VM opened a window but ignored every click. Two causes, both fixed here.
No absolute pointer (all VMs). A window or VNC VM had only qemu's default relative PS/2 mouse. A desktop guest cannot align its cursor to the host cursor from relative deltas, so the pointer drifts and clicks miss. Added
-device qemu-xhci -device usb-tabletso the guest cursor tracks the host cursor 1:1 in the gtk window and in a VNC client. This is OS-agnostic — it rides the QEMU command line for every VM.Alpine fed Xorg no input (Alpine only). Even with the tablet attached, XFCE got nothing. Alpine boots
mdev, and Xorg reads its input devices fromudev. The tablet'seventdevice existed but no driver bound it, so libinput saw no mouse or keyboard. The Xorg log said "The server relies on udev to provide the list of input devices" and then added none. The Alpine xfce recipe now runssetup-devd udev(switches the device manager to eudev, adds udev-trigger/udev-settle to sysinit) and cold-plugs, so X finds the pointer in the live session and after a reboot. Ubuntu, Debian, and Arch already run udev under systemd, so their scripts need nothing.Verified live: after
setup-devd udevand a reboot, the Xorg log showsAdding extended input device "QEMU QEMU USB Tablet" (type: MOUSE), and the desktop takes clicks.Tests:
TestArgsLivenow asserts the tablet on both the window and VNC paths.just checkandjust testpass.