Problem with L4re and L4Linux on Qemu/VMware

Adam Lackorzynski adam at
Fri Jun 23 00:44:11 CEST 2017

On Wed Jun 21, 2017 at 16:25:01 -0500, Daniel (Xiaolong) Wang wrote:
> I’m sorry to bother, again… But I keep getting problems hope you can give me some advice.
> I’m trying to test out L4re +L4Linux on X86 and ARM i.MX6. I downloaded the newest l4re-snapshot-2006082114. I built Fiasco with Intel Pentium Pro and Virtualization (did not change anything else).
> I built L4re with Pentium Pro type CPU (everything else are default settings). Then I built L4Linux with the L4re builddir. I turned off 64-bit kernel, CPU selected Pentium-Pro, turned off most of the settings as the warning instructed. 
> These are the settings of L4Linux that I enabled:
> Processor type and features:
> 	* DMA memory allocation support
> 	* Processor feature human-readable name
> 	* Fast CPU feature tests
> 	* Support for extended X86 platform
> 	* Single-depth WCHAN output
> 	* High memory support is OFF
> 	* Enable bounce buffers
> 	* X86 architectural random number generator
> 	* Enable seccomp to safety compute untrusted bytecode
> 	* Enable the LDT
> Power Management and ACPI options:
> 	* Suspend to RAM and standby
> 	* device power management core functionality
> 	* CPU Frequency scaling is OFF
> Bus Options:
> 	* PCI support
> 	* PCI access mode is Direct

That's ok. You can also use one of the defconfigs, e.g.

> I was able to compile all three parts and build both iso image (for vmware fusion on macOS) and qemu simulator. I first tested hello, hello-cfg, hello-shared, frame buffer-example-x86, all of those works as expected.

Ok, good.

> However when I tried to build L4Linux-basic and L4Linux-mag-x86. Not of them works.
> for L4Linux-mag-x86 the system shows a diagram “system is booting” then hang forever.

In such a case it is essential to have the serial output to see what's
going on as we won't see anything on the graphical screen in this case.

> for L4Linux-basic the image boot but freeze soon. The screen shows:
> 	l4cdds: No name given, not starting
> 	brd: module loaded
> 	l4cdds: no name given, not starting
> 	moused: ps/2 mouse device common for all mice
> 	l4x: Faking dummy RTC
> 	rtc_cmos rtc_cmos: rtc core: registered rtc_cmos as rtc0
> 	rtc_cmos rtc_cmos: only 24-hr supported
> 	rtc_l4x: l4x-rtc: Could not find ‘rtc’ cap
> 	rtc_l4x: probe of rtc-l4x failed with error -2
> 	NET: Registered protocol family 17
> 	L4IRQ: set irq type of 64 to 1
>      	RAMDISK: ext2 filesystem found at block 0
> 	RAMDISK: Loading 3072KiB [1 disk] into ram disk… done.
> 	VFS: Mounted root (ext2 filesystem) on device 1:0.
> 	Freeing unused kernel memory 188K (00494000 - 004c3000)
> 	Write protecting the kernel text: 2684K
> 	Write protecting the kernel read-only data 768k
> 	rodata_test: test data was not read only
> 	Please press Enter to activate this console. clocksource: tsc: mask: 0xffffffffffffffff max_cycles: 0x2845e81c5f6, max-idle_ns: 440795276432 ns
> 	clocksource: Switched to clocksource tsc

That actually looks good. It finished booting as it is supposed to do.
Is input not working, i.e. pressing enter?


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