Hi,Stefan
>The run-script you are using is an automated test, which remote-controls the test board by using >Tcl/expect. Therefore, if you use the unmodified run-script to control the Linux instance via serial line >manually, it won't work. The 'expect' mechanism holds control over the serial line I/O. That means >everything you type in will not be sent to the other side.

>If you want to use the test-scenario in a non-automated fashion, you either replace the very first >"run_genode_until ..." with "run_genode_until forever", or you simply do not use the run-script to
>connect to your test-board, but use a terminal emulator like "picocom" directly.

>Please, first evaluate whether it accepts input events with "direct" serial-line access. I'm wondering that >you see a _blinking_ terminal but no input events are shown.

Sorry,but I can not fully  understand what you mean. Now I am using i.mx53 quick start borad and the borad is connected to my PC through it's UART DB9 connector. I managed this through a USB to serial converter. Also , I use a serial debug tool that is "minicom" to get the output of the board and input my command.Through the minicom , I can input command to linux , such as "ls mkdir wget... etc" , also ,I can open the kernel module that I implemented to issue "smc" to switch to  tz_vmm to execute some code. It works fine when I use the genode 18.05. However ,when I changed to the hard-float version that you provided , I found this odd problem. Also, I have found that even I din't input any command the linux will get stuck after a period of time after startup. I have tried  to replace the "run_genode_until..." with "run_genode_until forever" but the result haven't changed. This problem has bothered me for a few days, I will be very grateful if you could give me some help. 

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Best wishes