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unhandled trap problem
by fabs0028＠free.fr 13 Jun '05

13 Jun '05

Hello, first i 'd like to thank you one more time for you support. It seems that my path to a proper l4linux is coming to an end but i still have one problem: at boot time when launching l4linux i got this problem : l4lx | mainmem: Number of physical regions: 1, 33554432 Bytes l4lx | mainmem: 1: Phys: 0x03182000 to 0x05182000, Size: 6175342 l4lx | Filling lower ptabs... l4lx | Done (885 entries). l4lx | l4x_setup_ti_thread_stack: ti = 0x905fe000 l4lx | l4lx_thread_create: Created thread 0c.05 (IRQ0 (Timer)) KERNEL: c.4 (tcb=c0302000) killed: Unhandled trap EAX ffffffff EBX 0071e000 ECX 00000064 EDX 0071d000 ESI 0100e3c0 EDI 0061f124 EBP 00665ec4 ESP 00665ec0 EIP 004e00dc EFLAGS 00013296 CS 001b SS 0023 DS 0023 ES 0023 FS 0023 GS 0043 trapno 13, error 00000000, from user mode (internal event regarding GDT entry no. 0x00) i want precise that i'm running fiasco and not fiasco-ux. so i disassembled at the given eip and i found that : ... linux-env/l4linux-2.6/arch/l4/lib/arch-i386/../../../i386/lib/mmx.c:158 004e00d9 sfence ... linux-env/l4linux-2.6/arch/l4/lib/arch-i386/../../../i386/lib/mmx.c:161 004e00dc mov %cr0,%eax 004e00df or $0x8,%eax 004e00e2 mov %eax,%cr0 004e00e5 pop %ebx 004e00e6 leave 004e00e7 ret so the problem occurs when the value of eax is put into cr0. i took a look into the source, the error was in static void fast_clear_page(void *page) and the line was kernel_fpu_end(); which is a macro for do { stts(); preempt_enable(); } while(0) in i387.h and stts is also a macro : #define stts() write_cr0(8 | read_cr0()) and we got those last two macro : #define read_cr0() ({ \ unsigned int __dummy; \ __asm__( \ "movl %%cr0,%0\n\t" \ :"=r" (__dummy)); \ __dummy; \ }) #define write_cr0(x) \ __asm__("movl %0,%%cr0": :"r" (x)); I don't know what the problem is, i thought i had left a bad option in my kernel configuration but i checked it and i saw nothing wrong for me (maybe i didn't see it). Thanx for your help. Fabien Chaillou

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Problem booting l4linux
by fabs0028＠free.fr 10 Jun '05

10 Jun '05

Hello I 'm trying to boot my fresh l4linux, i used the following entry in grub as adam previously told me to. title L4/Linux root (hd0,0) kernel /l4linux/rmgr -sigma0 task modname "L4Linux task" task modname "bmodfs" module module module modaddr 0x02000000 module /l4linux/fiasco -nowait -nokdb -serial_esc -comspeed 115200 -comport 1 module /l4linux/sigma0 module /l4linux/names module /l4linux/log module /l4linux/dm_phys module /l4linux/simple_ts -t 300 module /l4linux/l4io --noirq module /l4linux/bmodfs module /l4linux/libloader.s.so module /l4linux/run-l4 module /l4linux/vmlinuz26 module /l4linux/l4exec module /l4linux/loader --fprov=BMODFS run-l4 It starts but i get the following error messages : simplets|configured for 300 tasks bmodfs | L4RM: [PF] read at 0x00000000, eip 0122c495, src A.01 bmodfs | [A.0] l4rm/lib/src/pagefault.c:78:__unknowm_pf(): bmodfs | unhandled page fault It seems to be a problem with a null pointer and i'm sure it is a problem in my grub file but i don't know what's wrong. I tried to change some options but i always get this problem but it is not always the same server that crashes, it depends on my options. Thanx for the help Fabien Chaillou

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Loading shared objects in an l4env_freebsd application
by Derick Swanepoel 10 Jun '05

10 Jun '05

Hi again, I need to load shared objects in my application. I've got .so loading working in a loader-mode app, but my app uses the l4env_freebsd mode so I cannot link against libloader.s.so. I've tried to link against libloaderif.a, but the l4loader_attach_relocateable() function is only available in libloader.s.so. Any help would be appreciated, Derick

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questions on L4Env and libraries for development on pistachio
by Jayesh Salvi 10 Jun '05

10 Jun '05

I am looking for libraries to do coding on pistachio. As I understand L4Env gives a bunch of libraries - memory management libraries (dm_phys,...), l4io, etc. Could someone answer these questions: 1. From L4Env's docs I see it being used only with fiasco source code. Haven't come across any project that uses L4Env with pistachio. Any dependencies that I don't know of? If not are there any examples? 2. I want libraries for some basic functions - malloc, free, printf, etc. L4Env needs oskit, l4linux2.2 and fiasco L4 kernel. Aren't there any lightweight ways of getting such libraries for L4? Can parts of L4Env used seperately in pistachio tree? 3. I came across libCLight library which is the light implementation of libc. I could get it compiled in my pistachio tree, as done in IoL4 project. Can anyone compare using malloc in libCLight and using DMPhys of L4Env? Hope these questions are not that naive. Thanks in advance. -- Jayesh

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Grub problem
by fabs0028＠free.fr 09 Jun '05

09 Jun '05

Hello, i'm trying to create a l4linux system based on l4linux 2.6 and fiasco. i builded l4linux with l4env and fiasco from scratch with no problem but when i wanted to launch it i had problems with the grub version (gnu grub 0.95). I took your grub version as i was advised but i can't build it i have some problems, mainly with a reference to memcpy in some files in the stage2 directory, but what's weird is that there's no references to that fonction in the concerned files. For the record here is my grub menu.lst concerning l4linux title L4/Linux root (hd0,0) kernel /l4linux/rmgr task modname "bmodfs" module module module module /l4linux/fiasco module /l4linux/bmodfs module /l4linux/libloader.s.so module /l4linux/run-l4 module /l4linux/vmlinuz26 module /l4linux/loader --fprov=BMODFS run-l4 thanx for your help

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gettimeofday(2) and time(2)
by Derick Swanepoel 09 Jun '05

09 Jun '05

Hi all, I would like to get the current time as reported by gettimeofday(2) and time(2). However, neither of these functions seem to work in L4. gettimeofday() fills in the timeval struct with random values and time() always returns -1. What is the correct way to get the time in seconds since the Epoch in L4? Thanks in advance, Derick

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Re: [Fwd: Re: gettimeofday(2) and time(2)]
by Julian Grizzard 08 Jun '05

08 Jun '05

> use the RTC server. $(L4DIR)/pkg/rtc. Is $(L4DIR)/pkg/rtc part of the fiasco project CVS? If so, how do you check it out? Contents of my $(L4DIR)/pkg/ directory from 20050523 CVS: $ ls build/l4/pkg/ COPYING CVS hello l4sys Makefile rmgr crtx demangle l4lthread l4util oskit_support sigma0 Thanks! -Julian

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Status of the fiasco project
by fabs0028＠free.fr 08 Jun '05

08 Jun '05

Hello everyone, i'm a bit new in the world of L4. It is really interesting but it seems a wide world as well. I'd like to know if there will be a new version of fiasco in the near future and the main goal you are wanting to achieve for this hypothetic new version. Fabien Chaillou

2 1

l4linux2.4 System Call Emulation question
by Andrew Davenport 07 Jun '05

07 Jun '05

Hi, where in l4 does an exception (int 0x80) get trapped and turned into an appropriate l4 ipc and sent to l4linux? for instance: if (from an l4linux program), i do a system call like this (in assembly) mov bx, 0x20 mov ax, 0x10 int 0x80 where will i see 0x10 and 0x20 (the syscall parameters) inside the l4 IPC ?? Thanks very much in advance -andrew

2 1

l4linux question
by Andrew Davenport 04 Jun '05

04 Jun '05

Hello, I have a fiasco l4/l4linux system setup. I want to eventually log all linux system calls from within the fiasco kernel (via thread::sys_ipc and thread::shortcut_ipc). I am curious: How does a linux system call get translated into an l4 ipc ? Thanks, Andrew Winter Davenport

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