4 The Jailhouse hypervisor uses the printk and panic_printk functions for
5 printing messages. Both functions eventually call an architecture-dependent
6 function named 'arch_dbg_write()' which actually prints the message out
7 through a configurable hardware device. Typically, this hardware device
10 Although most ARM boards come with at least one serial port, modern x86
11 computers often lack it. In order to address such scenarios, the VGA console
12 feature provides an alternative debugging method for x86 computers based on
13 the VGA text mode buffer.
18 Add the following to the header section of your root cell's config:
21 .phys_start = 0xb8000,
23 .flags = JAILHOUSE_MEM_IO,
26 Boot using the following kernel parameters:
27 vga=normal nofb video=vesafb:off nomodeset i915.modeset=0
28 [Note] add also other jailhouse parameters such as memmap=66M$0x3b000000
30 Load the jailhouse kernel module. Use the 'vbetool' command to set the
31 current VESA mode and enable your root cell.
34 # vbetool vbemode set 3 && jailhouse enable configs/system.cell
36 [Note] for testing on QEMU replace 'system.cell' by 'qemu-vm.cell'.
41 [1] https://en.wikipedia.org/wiki/VGA-compatible_text_mode
42 [2] http://wiki.osdev.org/Text_UI