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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 05 Jun '13

05 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 03 Jun '13

03 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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