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Increase L4linux ramdisk size ?
by Julien Heyman 07 Apr '11

07 Apr '11

Hello, I am using Fiasco.OC/L4Re/L4Linux on a Beagleboard. After having successfully used/customized the L4Linux ramdisk provided as part of the snapshot, I created a larger ramdisk (8Mb instead of ~3Mb) from scratch and adjusted the "ramdisk_size" option on the linux boot args line in my LUA script, and rebuilt my u-boot image. I then get plenty of errors during linux boot, starting with: RAMDISK: ext2 filesystem found at block 0 RAMDISK: Loading 8000KiB [1 disk] into ram disk... l4linux1| Non-resolvable page fault at e0d1619, ip 170384. l4linux1| Page fault (non-resolved): pfa=e0d1619 pc=170384 l4linux1| Non-resolvable page fault at e0d161a, ip 170384. Internal error: Boom!: 410005 [#1] etc... My questions: - is there a specific way to create a ramdisk file for l4linux, and/or specific constraints on the ramdisk size ? - am I missing other configuration parameters than ramdisk_size that should be adjusted to reflect the larger ramdisk size ? Thanks, Julien

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How to block an API call without blocking server message loop?
by Valery V. Sedletski 05 Apr '11

05 Apr '11

Hi all. When an L4 server is started, its main thread goes into the server loop and blocks until a message from a client is received. When a message is received, a server loop calls a dispatch function, which calls functions, specific to RPC opcodes. The problem is that if one of these functions is blocked, the whole server loop is blocked. In my case, I am implementing an API, which is called by a client program. This API starts a child process, and has an option to block the calling program, until the child is terminated. This API is called DosExecPgm(). So, the client program calls this API, then the API call blocks, and then the child must be executed, and finally, call another API, which is called DosExit(). But when DosExecPgm is called, the server loop is blocked, and it cannot receive a message for calling the next API, DosExit. I tried to implement API call blocking using a semaphore. DosExecPgm from a parent process is waiting on the semaphore, and DosExit from a child process reset the semaphore. So, the problem is with server loop blocking. So, I thought to make for DosExecPgm a dedicated server loop. which is blocked, but the main server loop continues to execute. But how to correctly make these server loops? There are many API's which can block, so, what can I do if not to dedicate a separate loop for each function? And, if there are many server loops, then there will be many threads executing them, so I must to register each thread on the name server. -- Then how can the calling program determine, which server thread to call for each API? I feel that these problems have common solutions, but i'm in trouble -- maybe, someone will help with finding these common solutions? Thanks in advance, WBR, valery

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Build errors in building L4re for ARM
by Rahul Ramasubramanian 04 Apr '11

04 Apr '11

Hi I was trying to build l4re and ran into rather strange compilation errors. The code where the error is trowing up is in ../src/l4/pkg/bootstrap/server/src/startup.cc The relevant part of the error log looks like make[5]: Leaving directory `/home/rahul/newbuild_17_3_11/x86droid/l4Build/src/l4/l4rebuild/pkg/libvbus/lib/src/OBJ-arm_armv6zk-l4f' ==> "libcxx_libc_io_e.a" built ==> Installing libcxx_libc_io.a to local build-tree ==> Installing libcxx_libc_io_e.a to local build-tree make[5]: Leaving directory `/home/rahul/newbuild_17_3_11/x86droid/l4Build/src/l4/l4rebuild/pkg/cxx_libc_io/lib/src/OBJ-arm_armv6zk-l4f' make[4]: Leaving directory `/home/rahul/newbuild_17_3_11/x86droid/l4Build/src/l4/pkg/cxx_libc_io/lib/src' make[3]: Leaving directory `/home/rahul/newbuild_17_3_11/x86droid/l4Build/src/l4/pkg/cxx_libc_io/lib' make[2]: Leaving directory `/home/rahul/newbuild_17_3_11/x86droid/l4Build/src/l4/pkg/cxx_libc_io' ... Compiling ios_failure.o make[5]: Entering directory `/home/rahul/newbuild_17_3_11/x86droid/l4Build/src/l4/l4rebuild/pkg/libvbus/lib/src/OBJ-arm_armv6zk-l4f' ... Compiling vbus.o ... Compiling module.o ... Compiling ARCH-arm/crt0.o ... Compiling vbus_pci.o ... Compiling region.o ... Compiling ios_init.o ... Compiling vbus_gpio.o === Building package "libkproxy" === ... Compiling startup.o make[2]: Entering directory `/home/rahul/newbuild_17_3_11/x86droid/l4Build/src/l4/pkg/libkproxy' arm-none-linux-gnueabi-g++: Mar: No such file or directory arm-none-linux-gnueabi-g++: 31: No such file or directory arm-none-linux-gnueabi-g++: 18:28:52: No such file or directory arm-none-linux-gnueabi-g++: EDT: No such file or directory arm-none-linux-gnueabi-g++: 2011": No such file or directory <command-line>: warning: missing terminating " character /home/rahul/newbuild_17_3_11/x86droid/l4Build/src/l4/pkg/bootstrap/server/src/startup.cc:1054: error: missing terminating " character ... Compiling vbus_i2c.o make[5]: *** [startup.o] Error 1 make[5]: Leaving directory `/home/rahul/newbuild_17_3_11/x86droid/l4Build/src/l4/l4rebuild/pkg/bootstrap/server/src/OBJ-arm_armv6zk' make[4]: *** [/home/rahul/newbuild_17_3_11/x86droid/l4Build/src/l4/l4rebuild/pkg/bootstrap/server/src/OBJ-arm_armv6zk] Error 2 make[4]: Leaving directory `/home/rahul/newbuild_17_3_11/x86droid/l4Build/src/l4/pkg/bootstrap/server/src' make[3]: *** [src] Error 2 make[3]: Leaving directory `/home/rahul/newbuild_17_3_11/x86droid/l4Build/src/l4/pkg/bootstrap/server' make[2]: *** [server] Error 2 make[2]: Leaving directory `/home/rahul/newbuild_17_3_11/x86droid/l4Build/src/l4/pkg/bootstrap' make[1]: *** [bootstrap] Error 2 make[1]: *** Waiting for unfinished jobs.... ... Compiling ios-inst.o The toolcahin I am using is arm-linux-gcc-4.3.2.tgz, which I downloaded from some embedded system user group (www.friendlyarm.net) I think that this maybe has something to the toolchain. Can anyone point out why this error is and what i should do to fix this error . Thanks and Regards Rahul Ramasubramanian

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Question about Mapping DB Recursion Depth on Fiasco.OC
by Christoph Szeppek 24 Mar '11

24 Mar '11

Hello, as far as I understand, the mapping database consists of a treemap with an entry for each superpage. Each entry points to an array describing the page's mappings (mapping tree). Each element of this mapping tree either represents a mapping or stores the address of a treemap, if the superpage has been splitted into pieces with a size of the next smaller valid page size. Is it correct that an element of a mapping tree references another treemap only in case the page has been spllitted and therefor the maximum recursion depth is limited by the amount of valid page sizes? Christoph

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Customizing L4Linux, on ARM/Beagleboard
by Julien Heyman 24 Mar '11

24 Mar '11

Hello everyone, I would appreciate getting some advice as to the proper way to customize and rebuild an L4Linux kernel. I am testing Fiasco.OC/L4Re/L4Linux on a Beagleboard (ARM), I installed everything from the latest snapshot package, full build is fine, and launching the provided L4Linux "arm-up" kernel on my Beagleboard is ok. Now, to customize the configuration of the L4Linux kernel, I did "*make O=../../obj/l4linux/arm-up menuconfig*" from *\src\l4linux* directory, adjusted a few options, saved & exited, so far so good. Then I try to rebuild the L4Linux kernel using "*make O=../../obj/l4linux/arm-up*", and I get: *"<path...>/src/l4linux is not clean, please run 'make mrproper' in the '<path...>/src/l4linux' directory."* So I do just that, * <path..>/src/l4linux$ make O=../../obj/l4linux/arm-up mrproper* but : - it ends with an error *"rm: cannot remove `arch/l4/include/asm/orig-arch': Is a directory"* - as expected, it wipes out a lot of things in the target build directory, including... the *.config* corresponding to my customized kernel....back to square one. I must be missing something trivial, so if someone could point it out to me... ;) Regards, Julien

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Help on write first client-server on Fiasco
by Wenhao Xu 23 Mar '11

23 Mar '11

Hi guys, I am new to both microkernel and fiasco. All I read were some microkenel paper in the operating system course. After reading introduction to FIasco, I am very insterested in it. I have just compiled and run the hello demo in the Fiasco web page. Now I cannot wait to write my own client-server. I have never written an operating system before. Can you help me or give me some guide on how to write my first client-server in Fiasco? And are there window manager implementation or file system implementation for Fiasco? If not, I am also very interested in write one for Fiasco. Thanks very much for the help. Regards, Wenhao -- ~_~

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Fiasco.OC on amd64 Opteron 6000
by Daniel Waddington 16 Mar '11

16 Mar '11

Hi, I'm trying to run Fiasco.OC amd64 build on an Opteron 6100 magny-cours series (4-way-SMP, 12-cores-per-chip). When it boots it is as if the scheduling interrupt on the local APIC is not getting set up correctly. It also warns about some errata. It does boot with MP disabled, and RTC for the scheduling - not much use on a 48-core machine though ;-) Any clues??? Thanks, Daniel --- Per_cpu_data_alloc: (orig: 0xfffffffff0080840-0xfffffffff0081498) Allocate 3160 bytes (3KB) for CPU[43] local storage (offset=fc887c0) OSVW_MSR1 = 0x000000000000000c #Errata known 4, affected by at least one Allocate cpu_mem @ 0xffffffffffd0b000 Local APIC[19]: version=10 max_lvt=5 APIC ESR value before/after enabling: 00000000/00000000 Using the Local APIC timer on vector 90 (Periodic Mode) for scheduling CPU[43:25]: AuthenticAMD (10:9:1:0)[00100f91] Model: Unknown CPU at 2200 MHz 32/512 Entry I TLB (4K pages) 16 Entry I TLB (4M pages) 48/512 Entry D TLB (4K pages) 48/128 Entry D TLB (4M pages) 64 KB L1 I Cache (2-way associative, 64 bytes per line) 64 KB L1 D Cache (2-way associative, 64 bytes per line) 512 KB L2 U Cache (8-way associative, 64 bytes per line) 10240 KB L3 U Cache (13-way associative, 64 bytes per line) CPU[43]: goes to idle loop

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L4Re + Bytecode Translation
by Michael Brooks 16 Mar '11

16 Mar '11

I think it would be very interesting if the L4 Runtime Environment adopted a bytecode translator like the one implemented in Parrot VM<http://parrot.org/> or Nested VM <http://nestedvm.ibex.org/>. This feature would mean that L4 could support MANY LANGUAGES <http://trac.parrot.org/parrot/wiki/Languages> natively. So L4 would not only the ability to boot up a wide selection of operating systems, but also support for a wide selection of runtime environments. --Michael Brooks

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L4Linux - Freescale i.MX51 Bebbage Board - vmlinuz.arm wanted
by Siegfried Podesser 15 Mar '11

15 Mar '11

Hello everyone, I'm just trying since nearly a week to compile L4Linux. But neither the SVN-copy nor the snapshot (l4re-snapshot-2011022209) compiles at all. Before I will explain what I've already tried, my main question, can someone here send me a correct build vmlinuz.arm file ? What have I already tried: _'_'_'_'_'_L4 Linux from SVN _'_'_'_'_'_'_'_' 1. checked it out :) -> svn co http://svn.tudos.org/repos/oc/l4linux/trunk l4linux 2. kernel configuration and building -> make ARCH=arm mx51_defconfig O=build (or make ARCH=l4 mx51_defconfig O=build with recopying mx51_defconfig) -> make ARCH=arm all CROSS_COMPILE=arm-none-linux-gnueabi- O=build produces in any case a missing .config.all error where I have no idea how to produce/get it -->... make[3]: *** No rule to make target `/.config.all', needed by `/home/beresford/Work-Repositories/sepia/l4linux/build/Makeconf.l4conf'. Stop. make[2]: *** [/home/beresford/Work-Repositories/sepia/l4linux/build/Makeconf.l4conf] Error 2 GEN /home/beresford/Work-Repositories/sepia/l4linux/build/Makefile scripts/kconfig/conf --silentoldconfig Kconfig make[2]: *** No rule to make target `/.config.all', needed by `/home/beresford/Work-Repositories/sepia/l4linux/build/Makeconf.l4conf'. Stop. make[1]: *** [check_linux_config] Error 1 make: *** [sub-make] Error 2 _'_'_'_'_'_L4 Linux from snapshot file _'_'_'_'_'_'_'_' or with the snapshot in general (means for the existing realview platform and not for the mx51, just to see if it builds at least) 1. checked it out -> wget http://os.inf.tu-dresden.de/download/snapshots-oc/l4re-snapshot-2011022209.… 2. -> wget http://os.inf.tu-dresden.de/download/ramdisk-arm.rd für die ramdisk.arm 3. then unzipped 4. then I've tried it exactly as Wesley Miaw posted on Jan 4.1.11 with GCC_PATH_PREFIX=/opt/sourcery-g++-lite/bin/arm-none-linux-gnueabi- L4ARCH=arm make setup -> selected ARM realview make cd obj/l4linux/arm-up make arm_defconfig make menuconfig -> set L4 build path obj/l4/arm-rv -> set cross compile prefix arm-none-linux-gnueabi- -> turned on ARM EABI + old EABI binaries options make the last step does not build at all: ... /home/beresford/Work-Repositories/sepia/l4re-snapshot-2011022209/src/l4linux/include/linux/math64.h:51:15: note: each undeclared identifier is reported only once for each function it appears in In file included from /home/beresford/Work-Repositories/sepia/l4re-snapshot-2011022209/src/l4linux/include/linux/mm_types.h:11:0, from /home/beresford/Work-Repositories/sepia/l4re-snapshot-2011022209/src/l4linux/include/linux/sched.h:63, from /home/beresford/Work-Repositories/sepia/l4re-snapshot-2011022209/src/l4linux/arch/l4/kernel/../../arm/kernel/asm-offsets.c:13, from /home/beresford/Work-Repositories/sepia/l4re-snapshot-2011022209/src/l4linux/arch/l4/kernel/asm-offsets.c:5: /home/beresford/Work-Repositories/sepia/l4re-snapshot-2011022209/src/l4linux/include/linux/rwsem.h: At top level: /home/beresford/Work-Repositories/sepia/l4re-snapshot-2011022209/src/l4linux/include/linux/rwsem.h:22:65: fatal error: asm/rwsem.h: No such file or directory compilation terminated. make[3]: *** [arch/l4/kernel/asm-offsets.s] Error 1 make[2]: *** [prepare0] Error 2 make[1]: *** [sub-make] Error 2 make: *** [all] Error 2 Maybe someone has an idea. My development platform: Gentoo Linux 64bit, 2.6.37-rc1, GCC 4.5.2, arm-none-linux-gnueabi-... version (Sourcery G++ Lite 2010.09-50) 4.5.1 Thank you :) siegfried

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IPC performance comparison of Fiasco.OC and Pistachio
by Jaeyeon Kang 11 Mar '11

11 Mar '11

Hello, I have a question about IPC performance of Fiasco.OC and Pistachio. When I compared the performance for a pingpong benchmark, Pistachio provides better performance than Fiasco.OC (about 1.5 times faster). Is there anyone who can explain the reasons that Fiasco.OC's IPC is slower compared to Pistachio? Thanks, Jaeyeon

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