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A interprocess communication system for two l4linux instances
by Wajidali Whowe 05 Jul '13

05 Jul '13

Dear all, I am trying to implement an IPC method between two l4linux instances (lets call them as vmlinuz1 and vmlinuz2) using l4ser driver. Nevertheless both l4linux instances stuck during boot up printing, the following last sentence: "vmlinuz.| L4 serial driver" Going over the driver/tty/serial/l4ser.c file, I have seen that the stuck position line is in the function "l4ser_init_port"; "t = L4XV_FN(l4_msgtag_t, l4_icu_bind(l4ser_port[num].vcon_cap, 0, l4ser_port[num].vcon_irq_cap));" The following is my lua script: local ttyChannel = l:new_channel(); local hid = l:new_channel(); local linux_caps = { log = L4.Env.log:m("rws"); vbus = io_caps.linux_bus, rtc = rtc_caps.rtc, ev = hid:svr(), rom = L4.Env.rom, ttyMv0 = ttyChannel, }; l:start( { caps = linux_caps, }, "rom/vmlinuz1 mem=512M l4ser.add=ttyMv0 l4-input-srv.enable=1 console=ttyLv0 ramdisk=rom/myRamdisk root=1:0 ramdisk_size=190000 l4x_rd=rom/myRamdisk init=/sbin/init"); local linux_caps2 = { vbus = io_caps.linux_bus2, rtc = rtc_caps.rtc, rom = L4.Env.rom, ttyMv0 = ttyChannel, }; l:start( { caps = linux_caps2, }, "rom/vmlinuz.android mem=512M l4ser.add=ttyMv0 console=ttyLv0 ramdisk=rom/ramdisk root=1:0 ramdisk_size=190000 l4x_rd=rom/ramdisk init=/sbin/init"); How do you think that might cause the problem? Best regards and many thanks.

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Thought you'd find this interesting
by Rahul Singhal 30 Jun '13

30 Jun '13

Hi! I’ve just learned about the water crisis and thought you would be interested to check out this story: https://waterforward.charitywater.org/et/xclFZthf Let me know what you think! Thanks, Rahul -- Sent via WaterForward, an initiative of charity: water WaterForward, 387 Tehama Street, San Francisco, CA 94103, USA. Click here to unsubscribe: https://waterforward.charitywater.org/opt_out?et=xclFZthf

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15th Real Time Linux Workshop - Call for Papers
by Nicholas Mc Guire 25 Jun '13

25 Jun '13

15th Real Time Linux Workshop 1st Call for Papers October 28 - 31, 2013 Dipartimento tecnologie innovative Scuola universitaria professionale della Svizzera italiana Lugano-Manno Switzerland Following the meetings of academics, developers and users of real-time and embedded Linux at the previous 14 Real Time Linux Workshops held world-wide (Vienna, Orlando, Milano, Boston, Valencia, Singapore, Lille, Lanzhou, Linz, Guadalajara, Dresden, Nairobi, Prague and Chapel Hill) - the 2013 Real Time Linux Workshop will come to the Scuola Universitaria Professionale della Svizzera Italiana in Lugano-Manno, Switzerland. It will be held from October 28 to October 31, 2013. Rationale Real-time systems have evolved over the past decades in a relatively calm manner - performance has increased, one can say dramatically, but the main paradigms were pretty stable since the mid 80s. With the considerable increase of computing power, notably with multicore systems becoming mainstream in embedded devices, the requirements on RTOS are shifting and the tools are again trying to catch up. In stark contrast to 1999 (when the first RTLWS took place), Linux has a strong position in all kind of embedded systems, ranging from consumer electronics to network devices and a broad range of industrial applications including safety related systems. The technological resources suitable for high-availability, real-time, and safety critical systems have been continuously expanding and improving - allowing to cover the entire development life cycle of industrial projects based on open-source tools. At the core of this development is the availability of stable operating systems with reliable real-time properties. Extending and improving the real-time properties of Open Source RTOS is a continuous research and development effort. The OSADL has set itself the ambitious goal to document these efforts and it's most effective tool to do so is the annual Real Time Linux Workshop. Call for papers Authors from regulatory bodies, academics, industry as well as the user-community are invited to submit original work dealing with general topics related to Open Source and Free Software based real-time systems research, experiments and case studies, as well as issues of integration of open-source real-time and embedded OS. A special focus will be on industrial case studies and safety related systems. Topics of interest include, but are not limited to: - Modifications and variants of the GNU/Linux operating system and extending its real-time capabilities, - Contributions to real-time Linux variants, drivers and extensions, - Tools for the verification and validation of real-time properties, - User-mode real-time concepts, implementation and experience, - Real-time Linux applications, in academia, research and industry, - Safety related FLOSS systems, - Safety related systems using FLOSS components, - FLOSS Tools used to analyze, verify or validate safety properties, - Work in progress reports, covering recent developments, - Educational material on real-time Linux, - RTOS core concepts, RT-safe synchronization mechanisms, - RT-safe IPC mechanisms for RT and non RT components, - Analysis and benchmarking methods and results of real-time GNU/Linux variants, - Debugging techniques and tools, both for code and temporal debugging of core RTOS components, drivers and real-time applications, - Real-time related extensions to development environments Abstract submission If you wish to present a paper at the workshop, please submit an abstract using the submission page at https://www.osadl.org/RTLWS15-Abstract.submission-form.0.html. Final paper to be included into the RTLWS15 Proceedings Upon acceptance of an abstract by the RTLWS15 Program Committee, the author will be invited to submit a full paper in a form defined by https://www.osadl.org/paper.tgz. A detailed description of the editing and formatting process will be provided along with the notification email. Further information: http://www.osadl.org/RTLWS Important dates July 29, 2013 - Abstract submission deadline August 26, 2013 - Notification of acceptance September 23, 2013 - Submission of final paper October 28-31, 2013 - Workshop Organization committee: Local organizers: - Roberto Bucher, Scuola universitaria professionale della Svizzera italiana SUPSI, Switzerland OSADL/RTLF - Carsten Emde, OSADL - Nicholas Mc Guire, OSADL - Andreas Platschek, ICT, Vienna University of Technology, Austria Program committee: - Alexey Khoroshilov, ISPRAS, Russia - Andrea Bastoni, SYSGO AG, Germany - Andreas Platschek, TU-Wien, Austria - Bernhard N�lte, IQSE TueV SueD Rail, Germany - Carsten Emde, OSADL, Germany - Cheng Sheng, Beijing Shenzhou Aerospace Software Technology, China - Fans, Spectrum Sys, China - Georg Schiesser, OpenTech EDV Research, Austria - Herman H�rtig, Technische Universit�t Dresden, Germany - Julia Lawall, Inria/LIP6, France - Julien Delange, Carnegie Mellon Software Engineering Institute, USA - Klaus Reichl, Base Systems Technology Thales, Austria - Matthias Auchmann, A&R TECH, Austria - Michal Sojka, Czech Technical University in Prague, Czech Republic - Nicholas Mc Guire, OpenTech EDV Research, Austria - Paul E. McKenney, IBM Linux Technology Center, USA - Paolo Mantegazza, Politecnico di Milano, Italy - Peter Okech, University of Nairobi, Kenya - Peter Wurmsdobler, Aveillant Ltd, UK - Peter Zijlstra, RedHat, Netherlands - Philippe Gerum, Xenomai, France - Roberto Bucher, SUPSI, Switzerland - Shawn Choo, Weslab, Singapur - Stefan Schoenegger, B&R, Austria - Steven Rostedt, RedHat, USA - Thomas Gleixner, Linutronix, Germany - Yutaka Matsuno, University of Electro-Communications, Japan - Zhou Qingguo, DSLab, Lanzhou University, China Workshop organizers: - Dipartimento Tecnologie Innovative, SUPSI, Switzerland - Open Source Automation Development Lab (OSADL) Roberto Bucher Carsten Emde Nicholas Mc Guire Andreas Platschek

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How to run simple client server example
by Thang Tran 24 Jun '13

24 Jun '13

Hi, I'm new to Fiasco and L4Re. I want to write a new program in C++ which will run on L4Re. I'm looking at the simple client server example in the l4/pkg/examples/clntsrv directory for my reference. I was able to get it compiled eventually on L4Re, but I have no idea how to run it. Is there anyway that I can run examples/clntsrv package just like we run the hello package by using grub2iso and qemu? Thanks in advance, Thang Tran.

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Unable to boot 64bit hello
by Daniel Müller 14 Jun '13

14 Jun '13

Hi, I tried booting a 64bit hello world program on L4/Fiasco but that fails with a region overlap: ============================================= xc: info: VIRTUAL MEMORY ARRANGEMENT: Loader: 0000000000100000->000000000019dd88 TOTAL: 0000000000000000->000000007f800000 ENTRY ADDRESS: 0000000000100000 xc: info: PHYSICAL MEMORY ALLOCATION: 4KB PAGES: 0x0000000000000200 2MB PAGES: 0x00000000000003fb 1GB PAGES: 0x0000000000000000 Daemon running with PID 9320 net0: 00:16:3e:72:79:e5 using rtl8139 on PCI00:04.0 (open) [Link:up, TX:0 TXE:0 RX:0 RXE:0] DHCP (net0 00:16:3e:72:79:e5)... ok net0: 192.168.178.200/255.255.255.0 gw 192.168.178.54 Booting from PXE menu boot PXEBS (net0 type 128).... ok Next server: 192.168.178.54 Filename: pxeboot.0 tftp://192.168.178.54/pxeboot.0... ok L4 Bootstrapper Build: #7 Sun Jun 9 16:51:46 CEST 2013, x86-64, 4.6.3 RAM: 0000000000000000 - 000000000009a7ff: 618kB RAM: 0000000000100000 - 000000007f7b9fff: 2087656kB Total RAM: 2039MB New region for list regions: [ 20d000, 4c62c9] { 2b92ca} Root Module overlaps with: [ 2d0080, 2e45c7] { 14548} Boot bootstrap Regions of list 'regions' [ 0, fff] { 1000} Arch BIOS [ e0000, fffff] { 20000} Arch BIOS [ 106000, 1a646f] { a0470} Root Module [ 1a7000, 20c9bd] { 659be} Root Module [ 2d0080, 2e45c7] { 14548} Boot bootstrap [ 1013000, 10a8fff] { 96000} Boot bootstrap-ptab64 [ fc000000, ffffffff] { 4000000} Arch BIOS region overlap Key press reboots... ============================================= Everything works for 32bit. I took a look at bootstrap/server/src/startup.cc. I verified that modaddr is correctly passed to boostrap in both cases (32 and 64bit; it is 0x2000000 everytime). It appears that the failure happens in the call to add_boot_modules_region(): /* we're just a GRUB-booted kernel! */ add_boot_modules_region(mbi); if (_mod_addr) move_modules(mbi, _mod_addr); I do not fully understand all this code but to me this looks like a logic error: first the move should happen to honor "-modaddr" and only then the overlap check should be done. Here is the output for 32bit: ============================================= L4 Bootstrapper Build: #3 Sun Jun 9 16:55:38 CEST 2013, x86-32, 4.6.3 RAM: 0000000000000000 - 000000000009a7ff: 618kB RAM: 0000000000100000 - 000000007f7b9fff: 2087656kB Total RAM: 2039MB Moving up to 7 modules behind 2000000 moving module 00 { 139000-1ba783 } -> { 2829000-28aa783 } [530308] moving module 01 { 1bb000-21015e } -> { 28ab000-290015e } [348511] moving module 02 { 2e5000-51f51c } -> { 2901000-2b3b51c } [2336029] moving module 03 { 520000-762e3b } -> { 2000000-2242e3b } [2371132] moving module 04 { 763000-8880c6 } -> { 2243000-23680c6 } [1200327] moving module 05 { 211000-211080 } -> { 2369000-2369080 } [129] moving module 06 { 889000-9616a6 } -> { 236a000-24426a6 } [886439] Scanning /fiasco -serial -serial_esc -comspeed 115200 -comport 1 -nokdb Scanning /sigma0 Scanning /moe rom/hello.lua Bootloader MMAP: [ 0, 9a800) RAM (1) [ e0000, 100000) reserved (2) [ 100000, 7f7ba000) RAM (1) [ fc000000, 100000000) reserved (2) Relocated mbi to [0x2e0000-0x2e043f] Loading /fiasco Loading /sigma0 Loading /moe find kernel info page... found kernel info page at 0x400000 ... ============================================= Since the module addresses are also different between the two version this might also be an issue with the linker scripts (and thus just luck that the 32bit version boots), I would guess. I am using a Xen VM for testing. Any help would be appreciated. Thanks, Daniel

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How to make task run on different cores?
by Chao-Jui Chang 12 Jun '13

12 Jun '13

Hi, I start up 4 L4Linux on intel core2quad platform. In jdb, I can see 4 vmlinuz on the task list (command 's' in jdb). Next, I run 4 benchmarks, one in each L4Linux, but the experiment result shows that the 4 benchmark are running on the same core. The kernel seems not scheduling them to different cpu cores. I have enabled "Enable multi processor support" option in fiasco config menu and the jdb shows there are 4 cores: *** Cut start *** ----------------------------------------------------------------------- CPU 0 [f000d2a0]: IRQ ENTRY CPU 1 [f0022451]: Maskable Interrupt CPU 2 [f0022451]: Maskable Interrupt CPU 3 [f0022451]: Maskable Interrupt jdb: g *** Cut end *** But the running benchmarks are not showing on the task list(command 's' in jdb), is it normal? I remember in ARM L4Linux, the task list will show 'vmlinuz', 'sh', 'benchmark', ...,etc. Best Regards, Chao-Jui

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How Fiasco reclaim task resources when the task exits (abnormally) ?
by BogDan 11 Jun '13

11 Jun '13

Hello, What happens with a task resources when a task crashes or it leaks resources at exit? How this resources (e.g. memory, file descriptors, any other capabilities) are reclaimed back by the o.s. ? Cheers, BogDan.

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Re: Fiasco.OC with ARM TrustZone
by Chao-Jui Chang 11 Jun '13

11 Jun '13

Hi Adam, Thanks for your reply. After I change the memory to 1023, it runs but stops at ### Timer for CPU0 is at IRQ 28 Calibrating timer loop... ### By the way, how to turn on the module loading information during booting? The latest snapshot and svn only prints message starting from "Hello from Startup::stage2" ### Start cur ### Exynos4412 # run fiasco Partition1: Start Address(0x1000), Size(0x32000) reading bootstrap.raw 803080 bytes read Boot with zImage Starting kernel ... Hello from Startup::stage2 Number of IRQs available at this GIC: 160 FPU0: Arch: VFPv3(3), Part: VFPv3(30), r: 4, v: 9, i: 41, t: hard, p: dbl/sngl Watchdog initialized SERIAL ESC: allocated IRQ 305 for serial uart Not using serial hack in slow timer handler. Welcome to Fiasco.OC (arm)! L4/Fiasco.OC arm microkernel (C) 1998-2013 TU Dresden Rev: rUnversioned director compiled with gcc 4.5.2 for Samsung Exynos [] Build: #22 17:15:49 CST 2013 Timer for CPU0 is at IRQ 28 Calibrating timer loop... ### End ### Thanks, Chao-Jui 2013/5/12 Adam Lackorzynski <adam(a)os.inf.tu-dresden.de> > Hi, > > On Tue May 07, 2013 at 17:51:42 +0800, Chao-Jui Chang wrote: > > Is trustzone working on exynos 4412 platform? > > It is generally supposed to work but this also depends on the particular > board/system due to board configs etc. > > > I have selected the follow item in Fiasco config menu: > > * Platform Timer (Multi-core timer) > > * Use ExtGic > > * Execution Model (TrustZone normal side) > > > > But it stop at early stage. > > Same result for Execution Model (Standard mode). > > but no message for Execution Model (TrustZone secure side). > > One reason could be the configured amount of memory, is it 1023 or 1024MB? > > > If the trustzone is disabled in u-boot, the 'Standard mode' works fine. > > That could also indicate that. > > > > Adam > -- > Adam adam(a)os.inf.tu-dresden.de > Lackorzynski http://os.inf.tu-dresden.de/~adam/ > > _______________________________________________ > l4-hackers mailing list > l4-hackers(a)os.inf.tu-dresden.de > http://os.inf.tu-dresden.de/mailman/listinfo/l4-hackers >

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Program development for L4Re
by Rahul Singhal 11 Jun '13

11 Jun '13

I have recently ported l4 fiasco + l4Re on raspberry pi. I tested the port with the sample hello world program and it works fine.Now I want to write some of my own programs (C++, C and python) and run it on this environment. All I have done as of now is modify the sample hello world code a bit and test it. How do I go about doing this and where to start from? i appreciate your help. Regards Rahul

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Task threads are not killed at exit
by BogDan 10 Jun '13

10 Jun '13

Hello, Not all the task threads are killed when a task exits or it crashes. I've created a simple example here: http://paste.kde.org/760274 After application crashes (line 22), test thread is still alive, I still can see "Test thread alive" message printed. If I call exit or return instead to crash the task, the test thread is still alive . Cheers, BogDan.

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Re: <http://l4ka.org/> down?
by Thomas Schwinge 08 Jun '13

08 Jun '13

Hi! As the l4ka mailing list also seems to be defunct (though, my email didn't bounce), forwarding the question to the Dresden L4 folks as well as the registrant of the l4ka.org domain: On Thu, 06 Jun 2013 10:06:02 +0200, Thomas Schwinge <thomas(a)codesourcery.com> wrote: > On Wed, 05 Jun 2013 17:10:11 +0200, I wrote: > > On Wed, 5 Jun 2013 17:02:03 +0300, Fotis Koutoulakis <fotis.koutoulakis(a)gmail.com> wrote: > > > On http://www.gnu.org/software/hurd/microkernel.html the link for the > > > paper "On Microkernel Construction" appears to be dead. This patch > > > replaces the dead link with a working one. > > > > > [ mkernelconstructionurl.patch: application/octet-stream (as text/x-diff) ] > > > 14c14 > > > < [[Liedtke]] explains in [On Microkernel Construction](http://l4ka.org/publications/paper.php?docid=642) > > > [...] > > > As it appears that <http://l4ka.org/> generally is down (»Unconfigured > > server«) Now the server completely disappeared. > > at the moment. I suggest we wait a few days and see whether it > > comes back. If not (huh...), I'd like to use a more canonical [...] > > Any comments from the l4ka list? Is this a permanent outage, or just > temporary? Grüße, Thomas

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arm-linux-ld not found while compiling l4-fiasco microkernel
by Rahul Singhal 06 Jun '13

06 Jun '13

I am trying to port L4-fiasco + L4Re to raspberry pi. But when I compile fiasco, it throws an error saying arm-linux-ld not found. I found that I will need cross compiler binaries to compile the fiasco microkernel. But where to find them. Please help! Thanks in advance.

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Hello scenario gets stuck
by Markus Partheymueller 06 Jun '13

06 Jun '13

Hey, I'm having trouble booting the hello example on real hardware. The following config is booted via PXE: addr 0x2000000 exec mparthey/foc/bootstrap -serial load mparthey/foc/fiasco -serial -serial_esc -esc load mparthey/foc/sigma0 load mparthey/foc/moe load mparthey/foc/l4re load mparthey/foc/hello But it hangs after "MOE: Hello world". I can still enter the Kernel debugger, listing these task and thread objects: [Objects] 1 f007e020 [Task ] {KERNEL} R=2 6 ffdc6134 [Thread ] {KERNEL} C=0 R=1 current 7 fffe8f70 [Task ] {sigma0 } R=3 8 ffd80134 [Thread ] {sigma0 } C=0 S=D:7 R=3 9 fffe8f18 [Task ] R=3 a ffd83134 [Thread ] C=0 S=D:9 R=4 Backtrace on thread a yields an address 0x143d7d in moe (?), belonging to void List_alloc::merge() { List_alloc_sanity_guard __attribute__((unused)) guard(this, __func__); Mem_block *c = _first; while (c && c->next) 143d7d: 8b 00 mov (%eax),%eax 143d7f: 85 c0 test %eax,%eax 143d81: 75 ee jne 143d71 <_ZN22Single_page_alloc_base5_freeEPvmb+0x51> _ZN22Single_page_alloc_base5_freeEPvmb(): [...]/src/l4/pkg/moe/server/src/page_alloc.cc:109 } On a different machine the exact same setup works fine. Has anyone got a clue what goes wrong here? If I should get more information out of the kernel debugger, just let me know. Cheers Markus

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Re: How to catch unhandled exceptions ?
by Björn Döbel 04 Jun '13

04 Jun '13

Hi, [..] > So far so good! This is exactly what I want to do, to have a way to be notified > by the kernel about any exception of a thread. Now my problem is that I > get no notification when something bad happens (e.g. division by 0 or a > page fault), is there any example where I can look to see how to use > thread control + exc_handler and co ? I don't think I really know what to > pass to exc_handler method, I tried to pass a L4::Server_Object::obj_cap() > object but nothing happened ... The page fault handler and the exception handler are Fiasco.OC threads. Hence, you pass thread capabilities to those calls. Page faults go to the PF handler , all other exceptions end up in the exception handler thread. In the thread you would then do something like while (1) { msg = l4_ipc_receive(); inject_exception(); } In inject_exception() you can use the Thread::ex_regs system call, which allows you to modify the IP/SP of a thread. [..] >> Also, C++ exceptions need to be caught in the thread that raised the >> exception, otherwise the exceptions causes a call to std::terminate, >> wich will abort your application. Hence, you'd need try/catch statements >> for all potential hardware exceptions around all your threads' code. >> > > Of course you need to add try/catch statements :) The beauty is that if > you'll do it, you'll have a chance to survive to save your data, if not, > then, as you said, std::terminate will be called and you get the same > effect. There may be libraries (e.g., libc_be_signal) that spawn their own threads and where you do not have control over potential try/catch statements in their code. But that might not be an issue for you. >> I'm not saying it can't be done (I vaguely remember Choices OS [1] doing >> this), it's just not what we are doing on Fiasco right now. >> > > AH, sorry , I think is a misunderstanding here, I don't want you to do it in > Fiasco (even I think it will be very nice feature), I want to be able to do it > in my apps (at user-level not kernel level)! Sure, that's what I meant as well. Cheers, Bjoern

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target CPU does not support ARM mode
by Maximin Coste 04 Jun '13

04 Jun '13

I have a new error, appears from nowhere... I dowloaded the last L4RE version from the website, edited the mk/Makeconf file to put my "arm-none-aebi-" compilator and when i type: $ make O=build config/ I select ARM 7A / BeagleBoard, as usual, as it always worked... Here is my output: [...] <stdin>:1:0: error: target CPU does not support ARM mode [...] tmp.312625562.c:1:0: error: target CPU does not support ARM mode int main(void){} ^ He always create tmp file at the folder root whith nothing else than int main(void) {} inside. I did NOT change anything and everything was working fine yesterday.. Thanks, -- Maximin COSTE-LEENHARDT

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Region overflow in bootstrap
by Markus Partheymueller 04 Jun '13

04 Jun '13

When booting Fiasco/L4Re on my test machine (16G RAM, quad-core i7), I get the following error message, unless I have all CPUs and HyperThreading active: L4 Bootstrapper Build: #2 Mon Jun 3 14:15:47 CEST 2013, x86-32, 4.8.0 Limiting 'RAM' region [100000000, 43e5fffff] {33e600000} to [100000000, 10ea803ff] { ea80400} due to 3024 MB limit Bootstrap: add_nolimitcheck: Region overflow As soon as I deactivate CPUs in the BIOS or deactivate HT, it fails. Increasing the buffer __ram[8] to, e.g., __ram[16] in bootstrap/server/src/startup.cc:L67 does the trick. Maybe that buffer is too small for some machines?

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All *.cpp files are ignored by Makefile
by BogDan 02 Jun '13

02 Jun '13

Hi, I tried to add a few .cpp files to Makefile but it seems that L4Re build systems ignores this extension. This is the content of the Makefile: #################################### PKGDIR ?= ../.. L4DIR ?= $(PKGDIR)/../.. TARGET = test_cpp SRC_CC = main.cpp class1.cpp class2.cpp REQUIRES_LIBS = libstdc++ include $(L4DIR)/mk/prog.mk #################################### I tried to replace SRC_CC with SRC_CXX or SRC_CPP but with no luck ... This bug prevents the port of most of C++ libs out there to L4Re. BTW, is there any chance to use other build-systems (cmake, qbs, premake, SCons, etc.) to build L4Re libs/apps ? Cheers, BogDan.

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How to catch unhandled exceptions ?
by BogDan 02 Jun '13

02 Jun '13

Hi, Is there any way to catch all system unhandled exceptions (seg fault, fpu fault, etc.) and "transform" them into C++ exceptions ? I tried to use a combination of "L4::Thread::control" with "L4::Thread::Attr::exc_handler" to catch the system exception but it didn't worked for me, most probably I didn't understood the meaning of "l4_thread_control_exc_handler" or how to use it. Any example/help will be very appreciated. Of course, after I'll catch the exception, I need a way to "resume" the thread execution to another ip (address) which actually is a simple function that throws the C++ exception, any example/help on the matter will also be highly appreciated. Cheers, BogDan.

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Can't use cxx::Thread
by BogDan 02 Jun '13

02 Jun '13

Hello, I tried to create a very simple application that uses cxx::Thread, but I have some link problems: ... Compiling main.o ==> Linking test_cxx_thread main.o:(.rodata._ZTI10TestThread[_ZTI10TestThread]+0x8): undefined reference to `typeinfo for cxx::Thread' Also I think it will be cleaner/better for developers if run, execute and shutdown methods will be moved to a protected section. This is the main.cc content: /////////////////////////////////////////////// #include <iostream> #include <l4/cxx/thread> #include <thread> class TestThread : public cxx::Thread { public: TestThread():cxx::Thread(true){} private: virtual void run() { std::cout << "TestThread" << std::endl; } }; static void TestStdThread(int param) { std::cout << "TestStdThread param:" << param << std::endl; } int main(int argc, char ** argv) { (void)argc; (void)argv; TestThread cxxTh; cxxTh.start(); std::thread stdTh(TestStdThread, 1); for (;;) { std::cout << "Hello World!" << std::endl; sleep( 1 ); } stdTh.join(); } /////////////////////////////////////////////// This is the Makefile content: #################################### PKGDIR ?= ../.. L4DIR ?= $(PKGDIR)/../.. TARGET = test_cxx_thread SRC_CC = main.cc CXXFLAGS += -std=c++11 REQUIRES_LIBS = cxx_thread cxx_libc_io cxx_io libstdc++ libpthread include $(L4DIR)/mk/prog.mk #################################### Yours, BogDan.

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Kernel debugger in MP mode causes double fault
by Markus Partheymueller 01 Jun '13

01 Jun '13

Hi folks, has anyone tried to invoke the kernel debugger in a multiprocessor setup? When I boot the demo scenario in qemu with qemu -smp 2 -cpu core2duo and then hit Escape, the system crashes with a double fault. Without smp or with -cpu qemu32 the problem doesn't occur. Can someone confirm this issue or give a hint what could be wrong? Cheers Markus

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L4Re: FATAL: Exception Operation not permitted: ''"
by Maximin Coste 01 Jun '13

01 Jun '13

Hi, I'm running an edited and "old" (September 2012) version of L4Linux & uC-OS/II in top of Fiasco+L4RE (updated here). When launching the image I have generated, I have the following error: MOE: cmdline: moe rom/l4lx_ucos.cfg MOE: Starting: rom/ned rom/l4lx_ucos.cfg MOE: loading 'rom/ned' Ned says: Hi World! Ned: loading file: 'rom/l4lx_ucos.cfg' Ucos | L4Re: FATAL: Exception Operation not permitted: '' Ucos | Exception: Operation not permitted: : backtrace ... l4linux | L4Re: FATAL: Exception Operation not permitted: '' l4linux | Exception: Operation not permitted: : backtrace ... io | Dev_factory: register factory for N2Hw6DeviceE io | GTF: register factory for 7Pci_dev io | GTF: register factory for N2Hw12Msi_resourceE io | Dev_factory: register factory for N2Hw11Gpio_deviceE io | Io service io | Ready. Waiting for request. Can I see more about what's going wrong ? Can I see the backtrace those logs talks about ? :) -- Maximin COSTE-LEENHARDT

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How to boot Fiasco microkernel on raspberry pi
by Rahul Singhal 31 May '13

31 May '13

I want to port Fiasco microkernel to RPi. I found that Fiasco now supports RPi. I am a newbie in this kernel field. I have compiled the L4 microkernel and the L4 runtime environment for RPi succesfully but I don't know how to use the generated binaries to run RPi. I am running on ubuntu 12.04. Could you please tell me the procedure and files to be put on the sd card of RPi so that it boots into the L4 runtime environment.

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sigma0 memory space
by joel＠nider.org 31 May '13

31 May '13

I have been reading about the structure of L4Ka::Pistachio, and discovered that they use idempotent (1:1) page table mapping in their sigma0 process. I am wondering if Fiasco also takes this approach? If so, does the kernel also use idempotent mapping? I would imagine that this would have some implications on demand paging in the kernel. Does the kernel even use demand paging? (I mean at some point during boot the kernel will start to use memory to store kernel objects - either the kernel 'guesses' how much it will ever need and statically allocates that memory, or it's going to have to ask for pages later on, which will be owned by some other process). I tried to read the code, but found it very hard to traverse - the C++ classes don't make it easy to follow a flow. Can you please point out the file(s) where the kernel sets up the memory space for sigma0, and where it passes the initial ownership (from kernel space to sigma0 space)? Thanks, Joel

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Building l4re packages and linking errors
by Bryce Cronkite-Ratcliff 13 May '13

13 May '13

Hi folks, I'm afraid my configuration may have changed recently, possibly due to version changes in gcc, and I'm having some trouble compiling l4re, so I wanted to ping you to see if you had any insights. Two separate issues I've had: in an existing l4re build, executing make in an individual package sub-directory fails to find basic system headers in included files ("stddef.h" and "stdarg.h" for example). I'm running make O=basel4rebuilddir On the theory that l4re needs to be recompiled in order to set up links that may have changed since compilation of the last build, I've tried building l4re again, but I similarly run into a linker problem here: gcc: symbol lookup error: /home/bryce/L4Linux/x86/l4re4/tool/gendep/64/libgendep.so: undefined symbol: dlsym If you have any thoughts on what I might try, let me know! Thank you! Bryce

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Questions about Fiasco.OC and L4Re
by BogDan 13 May '13

13 May '13

Hello, First I'd like to introduce myself, I'm BogDan Vatra a free software hacker. Recently I've watched these http://wiki.tudos.org/HOWTOs#Introduction_to_Fiasco.OC_and_L4Re presentations on youtube. After I've seen them (many many times) I became fascinated. I started to "play" a little bit with Fiasco.OC and L4Re, I created a few apps and I must confess that I'm extremely impressed by your work. To me Fiasco.OC and L4Re seems way too good to be true, and I wonder if there are any "hidden traps" which prevents people to use it to create a general-purpose operating system on top of Fiasco.OC and L4Re, so my first question is: Can Fiasco.OC and L4Re be used to create free (GPL, BSD, apache, etc.) and non-free apps? I checked L4Re licenses and it seems that it has the necessary exceptions, but I'd like to be 100% sure :). I also look to Genode frameowrk and I it looks to me that it cannot be used to create non-GPL apps, so, it can not be used to create a general-purpose operating system where any kind of apps can run on it. I also have a few questions about the completeness of Fiasco.OC and L4Re: - does L4Re have any OpenGL support? I checked the source code and it seems that the only way to do graphics is via goos and it doesn't seem to have any OpenGL support. If I am right wouldn't be easier to port (and upstream) an existing server (e.g. xorg, wayland, mir, etc.) to L4Re, than to create one from scratch and maintain it? - does L4Re have any sound support? If it hasn't, then how hard will be to implement or to port an existing implementation? - does L4Re have any real filesystem support (e.g. ext2/3/4, xfs, raiser, etc.)? It is ok for testing to use qemu or grub to load simple apps, but for a real o.s., apps need to be loaded from disk. Again, if it hasn't, then how hard will to implement it or to port an existing implementation? - it is possible to use a debugger (e.g gdb(server)) to debug (user space) apps? - last but not least, is there any repository for Fiasco.OC and L4Re with logs? http://svn.tudos.org/repos/oc/tudos/trunk/ has no useful logs and IMHO it makes very hard any contribution to it. I've seen that you have a few repos on github (https://github.com/TUD-OS) do you have any plans to move Fiasco.OC and L4Re to github as well? IMHO being able to fork a repository and to create a pull request, to be able to open an issue and watch its progress will make contributors life much more easier :) ! Many thanks for your work! Yours, BogDan.

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