Hi, I have seen the following problem several times recently. This is with qemu-4.0.
qemu-system-x86_64: hw/usb/core.c:720: usb_ep_get: Assertion `dev != NULL' failed Backtrace gives me the following call path. main_loop() main_loop_wait() glib_pollfds_poll() aio_ctx_dispatch() aio_dispatch() aio_bh_poll() ehci_work_bh() ehci_advance_async_state() ehci_advance_state() ehci_execute() usb_ep_get() The problem always happens during shutdown, maybe once every 100 boots. It seems to be more likely to happen when the system is under heavy load. ... umount: devtmpfs busy - remounted read-only [ 49.018682] EXT4-fs (sda): re-mounted. Opts: (null) [ 49.028052] sd 6:0:0:0: [sda] Synchronizing SCSI cache qemu-system-x86_64: hw/usb/core.c:733: usb_ep_get: Assertion `dev != NULL' failed. Essentially that means that p->queue->dev is NULL in ehci_execute(). Has anyone else seen this problem ? Any idea what I can do to debug this further ? Thanks, Guenter