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the memory overlapping problem when loading the two duplicate components
by Guanghui, Cheng 02 Sep '09

02 Sep '09

Hello: I try to run the same two duplicate components on top of Fiasco but there is an error about memory overlapping problem. The problem is very simple which read the value of tsc looply like this: int main(int argc, char ** argv) { l4_uint64_t val; //rdtscll(val); l4_calibrate_tsc(); val = l4_rdtsc(); while(1) { printf("0x%0x:%0x\n", (unsigned long)((val>>32)&0xFFFFFFFF), (unsigned long)(val&0xFFFFFFFF)); //rdtscll(val); val = l4_rdtsc(); l4_sleep(2); } l4_sleep_forever(); return 0; } In the menu.lst this modules was loaded twice like this: module /rdtsc module /rdtsc When booting the error messsage is like this: #09: loading "/rdtsc" from [034c0000-034eff24] to [01000000-01003857][01004000-01009000] entry at 00065060 via trampoline page code symbols at [0eae2000-0eae3000] (4kB), lines at [0eade000-0eae2000] (16kB) #0a: loading "/rdtsc" from [034f0000-0351ff24] to [01000000-01003857] Roottask: cannot load binary because address at 01000000 not free loaded module: [034f0000-0351ff24) /rdtsc overlaps with: [01000000-01004000) #09 rdtsc Can i configure these two rdtsc with loading different address? Cheng

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My problem of I/O port
by Ding ying 02 Sep '09

02 Sep '09

Hello,everyone: I have built a parport server based on dde, and test it through on fiasco. Now I want to booting it together with l4linux, but there are conflict occured. And I have some questions to ask: 1. I used the l4linux-2.6.30 kernel, now to booting it besides fiasco default config, there is [ *] Enable I/O port protection feature must need, isn't it? It not needed in l4linux-2.6.23 kernel or earlier. 2. Will this feature prevent the other server to access to the io port? I seems meeting this problem, my parport server(#b) want to access the port 077a, but system say the owner is #a(l4io), even I set the parport priority higher than l4io, it also the same problem. the last error message is like follow: ............................... server | <6>parport0: PC-style at 0x378 [PCSPP,TRISTATE] server | <6>parport0: irq 7 detected ROOT: Cannot send port 077a to task #0b, owner is #a ROOT: task B.00 at 01804299 is trying to get I/O port 077a allocated by task 0b. ................................ How can I do could make the parport server run together with the l4linux, or to make it could access the port it needed? Any help is precious. Best Regards! ding

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Re: l4-hackers Digest, Vol 76, Issue 13
by fang zhengshu 02 Sep '09

02 Sep '09

hi all, could someone tell me how to get the thread id when do the open_call()/close_call()? or we can get the thread id unless wo do the l4_ipc_send() operation? I only want to get the thread id who do the open_call()/close_call() operation? When more than one task do the operation The server can store the thread id. thank you and best wishes. On Sun, Aug 30, 2009 at 6:00 PM, <l4-hackers-request(a)os.inf.tu-dresden.de>wrote: > Send l4-hackers mailing list submissions to > l4-hackers(a)os.inf.tu-dresden.de > > To subscribe or unsubscribe via the World Wide Web, visit > http://os.inf.tu-dresden.de/mailman/listinfo/l4-hackers > or, via email, send a message with subject or body 'help' to > l4-hackers-request(a)os.inf.tu-dresden.de > > You can reach the person managing the list at > l4-hackers-owner(a)os.inf.tu-dresden.de > > When replying, please edit your Subject line so it is more specific > than "Re: Contents of l4-hackers digest..." > > > Today's Topics: > > 1. Re: can server side get the thread id of client side? > (fang zhengshu) > > > ---------------------------------------------------------------------- > > Message: 1 > Date: Sun, 30 Aug 2009 02:57:16 -0400 > From: fang zhengshu <fangzhsh07(a)gmail.com> > To: l4-hackers(a)os.inf.tu-dresden.de > Subject: Re: can server side get the thread id of client side? > Message-ID: > <a73d246f0908292357w7ddaed5cwdb2a3013b07020c5(a)mail.gmail.com> > Content-Type: text/plain; charset="iso-8859-1" > > hi all, > > 3. Re: can server side get the thread id of client side? > > (Bj?rn D?bel) > > Message: 3 > > Date: Fri, 28 Aug 2009 09:40:17 +0200 > > From: Bj?rn D?bel <doebel(a)os.inf.tu-dresden.de> > > To: L4 Hackers <l4-hackers(a)os.inf.tu-dresden.de> > > Subject: Re: can server side get the thread id of client side? > > Message-ID: <4A9789E1.7080503(a)os.inf.tu-dresden.de> > > Content-Type: text/plain; charset=ISO-8859-1 > > > > -----BEGIN PGP SIGNED MESSAGE----- > > Hash: SHA1 > > > > Hi, > > > > > I know that the client side can get the server's thread_id throw name > > > service. I want to ask can the server side get the client's task_id or > > > thread_id? > > > or must the client side send the thread_id to server? > > > > your server will call either l4_ipc_wait() or l4_ipc_reply_and_wait() in > > order to receive the message from the client. In both cases there is a > > src parameter which will contain the client's thread ID after the system > > call returns. > > > sorry for not explaining it clearly. > if I defined two functions in idl file, just like: > interface test{ > int open(int fd, int flags); > int close(fd); > }; > > and I implement them in the server side. > I know that when I use open()/close() in the client side, the server will > call the function open_component()/close_component() which are in the > server > side. > > In the open_component()/close_component() function I want to get thread id > of the caller to do some operation flag.but as we know, when we call > open()/close() in client side, the open_component()/close_component() > function in server side will be executed. so we can not use l4_ipc_wait() > or > l4_ipc_reply_and_wait() function in the open_component()/close_component() > function, or it will be stop and wait for a message in the function. So in > order to get the thread id in the open_component()/close_component(), when > or where should I use the l4_ipc_wait() or l4_ipc_reply and wait() to get > the thread id? > > thank you! > > > > > > -- > fang, >

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Re: can server side get the thread id of client side?
by fang zhengshu 30 Aug '09

30 Aug '09

hi all, 3. Re: can server side get the thread id of client side? > (Bj?rn D?bel) > Message: 3 > Date: Fri, 28 Aug 2009 09:40:17 +0200 > From: Bj?rn D?bel <doebel(a)os.inf.tu-dresden.de> > To: L4 Hackers <l4-hackers(a)os.inf.tu-dresden.de> > Subject: Re: can server side get the thread id of client side? > Message-ID: <4A9789E1.7080503(a)os.inf.tu-dresden.de> > Content-Type: text/plain; charset=ISO-8859-1 > > -----BEGIN PGP SIGNED MESSAGE----- > Hash: SHA1 > > Hi, > > > I know that the client side can get the server's thread_id throw name > > service. I want to ask can the server side get the client's task_id or > > thread_id? > > or must the client side send the thread_id to server? > > your server will call either l4_ipc_wait() or l4_ipc_reply_and_wait() in > order to receive the message from the client. In both cases there is a > src parameter which will contain the client's thread ID after the system > call returns. > sorry for not explaining it clearly. if I defined two functions in idl file, just like: interface test{ int open(int fd, int flags); int close(fd); }; and I implement them in the server side. I know that when I use open()/close() in the client side, the server will call the function open_component()/close_component() which are in the server side. In the open_component()/close_component() function I want to get thread id of the caller to do some operation flag.but as we know, when we call open()/close() in client side, the open_component()/close_component() function in server side will be executed. so we can not use l4_ipc_wait() or l4_ipc_reply_and_wait() function in the open_component()/close_component() function, or it will be stop and wait for a message in the function. So in order to get the thread id in the open_component()/close_component(), when or where should I use the l4_ipc_wait() or l4_ipc_reply and wait() to get the thread id? thank you! -- fang,

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can server side get the thread id of client side?
by fang zhengshu 28 Aug '09

28 Aug '09

hi all, I want to write a simple example in l4, and there are to task module: client,server in the client side, I use the interface which is inplemented in server side.like: int open(int fd, int flags) I know that the client side can get the server's thread_id throw name service. I want to ask can the server side get the client's task_id or thread_id? or must the client side send the thread_id to server? thank you. -- fang,

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Re: l4-hackers Digest, Vol 76, Issue 10
by fang zhengshu 28 Aug '09

28 Aug '09

hi all, I want to write a simple example in l4, and there are to task module: client,server in the client side, I use the interface which is inplemented in server side.like: int open(int fd, int flags) I know that the client side can get the server's thread_id throw name service. I want to ask can the server side get the client's task_id or thread_id? or must the client side send the thread_id to server? thank you? -- fang,

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one question about l4_thread_ex_regs flags
by Guanghui, Cheng 26 Aug '09

26 Aug '09

Hello: About the l4_thread_ex_regs system call there are 2 flags related with exception ipc. I only know the thread with these flags could generate the exception ipc but i don't know what is the difference between these flags: L4_THREAD_EX_REGS_RAISE_EXCEPTION , L4_THREAD_EX_REGS_ALIEN and L4_THREAD_EX_REGS_ALIEN | L4_THREAD_EX_REGS_ALIEN. So, i write a following program to test the behaviour with different flags : void idle(void *data) { l4_sleep(1000); l4_sleep(1000); l4_sleep(1000); l4_sleep(1000); l4_sleep(1000); } int main() { ... l4_threadid_t me = l4_myself(); l4thread_create(idle, NULL, L4THREAD_CREATE_ASYNC); ... l4_thread_ex_regs_flags(idle_thread, ~0UL, ~0UL, &_preempter, &me, &o, &o, &o, L4_THREAD_EX_REGS_RAISE_EXCEPTION | L4_THREAD_EX_REGS_ALIEN); while(1) { l4_ipc_wait(&src, ...); printf("thread :%d:%d\n", src.id.task, src.id.lthread); } } I tried 3 combination about these 2 flags but the output is the same as this: exceptio| thread :8:3 i don't know why there is only one exception ipc. But the idle function includes 5 system calls. Additionally, it seems the ALIEN state is TEMPORARILY. I set once there is one exception ipc, twice two exception ipc. Can you explain me? Thanks. Cheng Guanghui

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Re: seL4 kernel is formally verified
by gernot＠cse.unsw.EDU.AU 18 Aug '09

18 Aug '09

On Tue, August 18, 2009 10:18 am, John van V. wrote: > Doesn't load. Apologies, that was the link to the internal stage site. The correct link is http://ertos.nicta.com.au/research/l4.verified/ Gernot

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seL4 kernel is formally verified
by Gernot Heiser 17 Aug '09

17 Aug '09

Hi, For those out there who missed the publicity (incl ./): NICTA announced last week that the formal verification of our seL4 kernel has been completed. This makes seL4 the first ever general-purpose OS kernel with a formal proof that the implementation is consistent with the specification. A paper on the project will appear in this year's SOSP. Details at http://ertos.nicta.com.au/news/home.pml#verified Gernot

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Howto implement a periodic real-time task?
by Andre Puschmann 10 Aug '09

10 Aug '09

Hey guys, I got a L4 real-time application that should run strictly periodic. In each cycle I have to communicate with at least two other L4 threads in different address spaces. The cycle period is in the order of 1000Hz to 5000Hz. As described in [1] I tried to use the CPU reservation server but the sample implementations did not work. Anyway, I figured out that even the CPU reservation server depends on the kernel timer and thus the granularity is 1ms (in PIT mode), which is too coarse for cycle periods larger then 1000Hz. Although I like the idea to use OS primitives to keep the application as portable as possible (ARM port is a goal), I thought about implementing the periodic execution with an extra timer decoupled from the scheduling timer which generates an IRQ at each hit. Any comment/suggestions/ideas about that? Any other experience with periodic real-time tasks on L4? Cheers, Andre [1] http://os.inf.tu-dresden.de/pipermail/l4-hackers/2009/004179.html

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