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L4 SCSI driver
by dmiller 10 Jun '02

10 Jun '02

dear l4-hackers does any version of L4 have an adaptec SCSI driver? we are trying to add an adaptec 2940UW SCSI driver to the Sombrero Single Address Space OS I have taught L4 as the topic of my OS internals course (using the L4 version available from UNSW) - but can't find such a driver in that source thanks for any info you have on this don miller -- Donald S. Miller Associate Professor Computer Science and Engineering Department Arizona State University Tempe, AZ 85287-5406 email: donald.miller(a)asu.edu http://www.eas.asu.edu/~sasos phone: (480)-965-5935 Fax: 480/965-2751

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DE use
by luke.hart＠sysmedia.com 02 May '02

02 May '02

All, The latest version of L4 (from CVS) and probably earlier ones, check for the debug extensions. Does it actually use them? I ask this since Bochs, does not set the DE bit in the CPUID or support these extensions. I have done a search for usage of DRx (where x is 0-7) in the source, but couldn't find any references. Is it safe to just remove the check for DE? Thanks for any info., Luke

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RE: DE use
by Volkmar Uhlig 01 May '02

01 May '02

What kernel? Hazelnut or FIASCO? > -----Original Message----- > From: luke.hart(a)sysmedia.com [mailto:luke.hart@sysmedia.com] > Sent: Wednesday, May 01, 2002 1:42 AM > To: l4-hackers(a)os.inf.tu-dresden.de > Subject: DE use > > > All, > > The latest version of L4 (from CVS) and probably earlier > ones, check for the > debug extensions. Does it actually use them? I ask this since > Bochs, does > not set the DE bit in the CPUID or support these extensions. > > I have done a search for usage of DRx (where x is 0-7) in the > source, but > couldn't find any references. Is it safe to just remove the > check for DE?

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L4 SCSI driver
by dmiller 19 Apr '02

19 Apr '02

Gernot a quick question does any version of L4 have an adaptec SCSI driver? we are trying to add an adaptec 2940UW SCSI driver to Sombrero thanks for any info you have on this don -- Donald S. Miller Associate Professor Computer Science and Engineering Department Arizona State University Tempe, AZ 85287-5406 email: donald.miller(a)asu.edu http://www.eas.asu.edu/~sasos phone: (480)-965-5935 Fax: 480/965-2751 --

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L4 for asm-free OS'es?
by William A. Gatliff 09 Apr '02

09 Apr '02

Guys: I'm an L4 newbie. I've booted it on my PC, I've read a lot of the online docs, and I've looked at some of the code. But I've been doing embedded systems for more than ten years now, so I know a thing or two about computers and operating systems. I'm interested in using L4 as a foundation for a new, yet-to-be-written Linux replacement intended primarily for use in embedded systems. My main motivations are for an OS that is portable, is understandable, has low interrupt latency, and has a small memory footprint. I'm thinking along the same lines as L4-Linux, but my OS would probably be written in C++ and make more use of L4 servers for hardware i/o. Here are my questions: One of the L4 manuals I've read says that when an OS running under L4 starts, it should take all free memory from sigma0 and then manage the pages itself. To me, this means that the OS has to know how to interact with the host CPU's MMU hardware, which is obviously hardware-dependent and therefore undesirable in a portable OS. It also appears to be redundant--- sigma0 already knows how to work the MMU. Performance issues aside, would letting sigma0 do page mapping and unmapping eliminate the need for an OS running under it to know how the MMU interface works, and thereby make the OS a little more portable? Is this a reasonable approach? What is the likelihood that an L4-based OS would need no assembly language at all, other than the syscall interface? I'm thinking along the lines of "to port this OS to your CPU, just port L4 and then recompile the OS sources." I'm eyeing ARM, MIPS, SH and x86 targets--- all of which I work with every day. I have single-board computers representing all four architectures in my lab here right now, and I'm doing something with all of them almost all the time. That's why portability is important to me. My customers think Linux is great because it's more portable than the alternatives, but I think it isn't nearly portable enough. And it scores low marks for understandability, interrupt latency and footprint. Oh, and debuggability---I love your "KD:" prompt! :^) Thanks! b.g. -- Bill Gatliff bgat(a)billgatliff.com

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RE: L4 for asm-free OS'es?
by Josh English 09 Apr '02

09 Apr '02

I was told that BeOS used a similar C++ structure. Though I have no idea how it was really implemented. - Josh -----Original Message----- From: Patrick Strasser [mailto:past@sbox.tugraz.at] Sent: Monday, April 08, 2002 5:29 PM To: bgat(a)billgatliff.com Cc: l4ka(a)ira.uka.de; l4-hackers(a)os.inf.tu-dresden.de Subject: Re: L4 for asm-free OS'es? William A. Gatliff wrote: > A lot of what I see happening in the C parts of Linux could be done > *so* much better with C++. I'm thinking of an OO-oriented driver > model as an example, rather than just a soup of C functions that you > have to invoke in the proper order for things to work right. "Want to > right a USB driver? Well then just inherit from USBDriver and fill in > these functions for the bulk transfers." You know, like that. :^) You probaly want to have a look at MacOS X / Darwin and its IOKit. Thats exactly what they do. Patrick _______________________________________________ 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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IDL4 0.8.1 released
by Andreas Haeberlen 06 Apr '02

06 Apr '02

Hello L4 hackers, IDL4 is now available for download from the L4Ka home page. IDL4 is a stub-code generator for the L4 platform. It generates communication stubs from interface definitions written in a specification language such as CORBA IDL or DCE IDL. It also uses knowledge about the hardware platform and the microkernel to optimize the performance of the generated code. Some features: o Supports CORBA IDL (recommended) and DCE IDL o Backends available for Hazelnut and Pistachio o Client stubs use CORBA C language mapping o Type import from C/C++ code o Modular design; easily extensible For more information please visit http://l4ka.org/projects/idl4/ - Andreas --- Andreas Haeberlen System Architecture Group, University of Karlsruhe, Germany haeberlen(a)ira.uka.de, phone: +49 (721) 608-4055

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Fiasco and linux22 -- RMGR: overlapping modules problem
by Ian Duggan 23 Mar '02

23 Mar '02

I'm trying to get linux22 working on the recent CVS version of fiasco. I've run into an obstacle that hopefully someone here can assist with. When my machine is booting up, I get an "overlapping modules" error that looks like this: ------------------------------------------------------- RMGR: loading /sigma0 RMGR: loading kernel /main RMGR: overlaps: 00300000-00301c78 : /main RMGR: 00100000-0015fc69 module 02: 001e6000-00345be4 : /glinux root=/dev/hdb1 init=/bin/sh overlaps, 1, mem_high = 0x09f9fc00 RMGR: overlapping modules ------------------------------------------------------- 00300000 is the starting link address of /main 00100000 is the starting link address of /rmgr I thought that maybe I needed to move the starting link address of /glinux, so I adjusted the corresponding vmlinux.lds file used for linking linux22, but there is no change in the result. I verified all code start/end addresses using objdump -d. Just now I noticed that 001e5000 is where GRUB is loading the /glinux image to. Grub shows: [Multiboot-modules @ 0x1e6000 ... when it is starting up. The problem seems to be that rmgr is calling check_inside_myself and croaking when it sees that the /glinux module overlaps it. I don't understand why the /main and /rmgr images are being loaded to their correct link locations, but /glinux is not. Is grub supposed to load things directly to the correct location, or are the modules supposed to be relocated at some point in the boot process. Any suggestions on what to look at? -- Ian ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ Ian Duggan ian(a)ianduggan.net http://www.ianduggan.net

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Re: L4Env
by Ian Duggan 11 Mar '02

11 Mar '02

What is the latest status on the L4ENV stuff? --Ian > > Ian Duggan <ian(a)ianduggan.net> writes: > > > Where can I find out more information about the L4Env project? I'm > [...] > > presentation can be foud at > > http://os.inf.tu-dresden.de/~reuther/helmuth.pdf > > http://os.inf.tu-dresden.de/~reuther/helmuth_slides.pdf > > There is also a small webpage at > http://wwwos.inf.tu-dresden.de/~ch12/diplom/diplom.xml > > I will put more up-to-date documentation (doxygen) about my implementation on > it as far as I cleaned up the sources. ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ Ian Duggan ian(a)ianduggan.net http://www.ianduggan.net

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(no subject)
by tinker1 french 12 Feb '02

12 Feb '02

still looking for way to find pharmacys directory for overseas. _________________________________________________________________ Send and receive Hotmail on your mobile device: http://mobile.msn.com

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L4 Version X.2 announcement
by Uwe Dannowski 28 Jan '02

28 Jan '02

The L4Ka Team is happy to announce the availability of the L4 microkernel API specification, Version X.2. The specification can be downloaded in PDF format from the L4Ka web-site (http://l4ka.org/) It should be noted that the Version X.2 specification is experimental. Future revisions may contain modifications and introduce incompatibilities with the current revision. It is nevertheless our intention that the amount of changes to the specification should be small, and that the X.2 specification should deviate as little as possible from the forthcoming Version 4 specification. The L4Ka Team is currently working on providing a reference implementation for the specification. No release date has been chosen. - The L4Ka Team

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L4/Alpha palcodes
by Goswin Brederlow 25 Jan '02

25 Jan '02

Hi, I hope this is the right place, havent read anything here for ages. I was wondering whether the palcodes used by L4 on Alpha are disjunct to the ones used by OSF / BSD / Linux. If not could they be made disjunct? The idea I have in mind is to make a module for linux that catches the L4 syscalls and throws them back into user-space. That way a L4 environment could be setup within linux. It would be much like user-space-linux and would save a lot of reboots just to test out a few bytes of code. On the other hand, inside L4 you could do the same with OSF / BSD / Linux syscalls and thus run their binaries under L4. (You want to run Netscape under L4? Or Mathematica? Or something as simple as xemacs and gcc?) A l4-linux for alpha would also need those changes (if any) I believe. MfG Goswin

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RE: L4/Alpha palcodes
by Sebastian Schoenberg 22 Jan '02

22 Jan '02

Yes, they were set to numbers which do not conflict with OSF/Linux/WinNT. A PALcall instuction is coded as cmd (6 bits) = 0, number (26 bits). There are two ways of calling PALcode: A direct way, where a certain address is called, or an indirect way, which must examine the calling instruction to jump to the right place. All L4Alpha PALcalls are located at the end of direct-callable PALcalls, hence they are fast and do not conflict with any other system Seb > -----Original Message----- > From: Daniel Potts [mailto:danielp@cse.unsw.edu.au] > Sent: Dienstag, 22. Januar 2002 09:50 > To: Goswin Brederlow > Cc: l4-hackers(a)os.inf.tu-dresden.de > Subject: Re: L4/Alpha palcodes > > > On 22 Jan 2002, Goswin Brederlow wrote: > > > Hi, > > > > I hope this is the right place, havent read anything here for ages. > > > > > > I was wondering whether the palcodes used by L4 on Alpha > are disjunct > > to the ones used by OSF / BSD / Linux. > > yes they are. An exception is l4_whoami which is an > experimental syscall anyway. I think it maps directly to the > OSF whoami call. > > > > > If not could they be made disjunct? > > > > > > The idea I have in mind is to make a module for linux that > catches the > > L4 syscalls and throws them back into user-space. That way a L4 > > environment could be setup within linux. It would be much like > > user-space-linux and would save a lot of reboots just to test out a > > few bytes of code. > > heh :) That would be an interesting project. I'd be > interested to know how (if) you will deal with device > drivers, memory etc. > > > On the other hand, inside L4 you could do the same with OSF / BSD / > > Linux syscalls and thus run their binaries under L4. (You > want to run > > Netscape under L4? Or Mathematica? Or something as simple as xemacs > > and gcc?) > > > > > > A l4-linux for alpha would also need those changes (if any) > I believe. > > Yes that is how we would run unmodified Linux/Alpha binaries on L4.. > > Cheers, > Daniel > > _______________________________________________ > 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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L4\UltraSPARCIIi?
by Crusher 20 Jan '02

20 Jan '02

I'm a graduate student at CSUS (California State University Sacramento). I was looking around the Internet for a Master's Project. I decided that since no one has ported L4 to the UltraSPARCIIi I would attempt it (as this is my first kernel, I'm not expecting too much), especially since the school has plenty of Sun machines around. I do already have a Sun Ultra 5 workstation and the development environment just about setup. Before I really started in on my project, I just wanted to make sure that a L4 port to the UltraSPARC isn't in the works or has been completed. Otherwise, I was hoping someone has done system work with the UltraSPARC and would be willing answer some of my UltraSPARC specific technical questions that I know will come up. Scott Tanaka

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OSKit-Problems with newer glibc
by imi＠inf.tu-dresden.de 17 Jan '02

17 Jan '02

Hi Are there any reported solutions for compiling the oskit1.0 that comes with l4 with installed glibc 2.2.4 or newer? On my machine (Debian "sid", gcc 2.95.4) it throw a linker error while linking unix/linux/sbrk-hack.o together with libc.a because duplicate symbol __libc_multiple_libcs. The sbrk-hack's only purpose seems to be defining these global variable (as an int). Maybe this was an error in libc and got fixed in 2.2.4? However when I compiled under glibc 2.1.3-10 (and gcc 2.95.2) it works... -- Immanuel Scholz, PGP: (Work 0x9216F1E7, Home 0x3B5DC02D)

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OSKit-Problems with newer glibc
by imi＠wh9.tu-dresden.de 16 Jan '02

16 Jan '02

Hi Are there any reported solutions for compiling the oskit1.0 that comes with l4 with installed glibc 2.2.4 or newer? On my machine (Debian "sid", gcc 2.95.4) it throw a linker error while linking unix/linux/sbrk-hack.o together with libc.a because duplicate symbol __libc_multiple_libcs. The sbrk-hack's only purpose seems to be defining these global variable (as an int). Maybe this was an error in libc and got fixed in 2.2.4? However when I compiled under glibc 2.1.3-10 (and gcc 2.95.2) it works... -- Immanuel Scholz, PGP: (Work 0x9216F1E7, Home 0x3B5DC02D)

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2nd release of L4Ka/Hazelnut
by Uwe Dannowski 14 Dec '01

14 Dec '01

Hi L4 hackers and users, after a long wait it's again time to announce a new release of L4Ka/Hazelnut. L4Ka/Hazelnut still implements the L4 Version X.0 API on x86 and ARM processors. This time around, however, it outperforms Jochen's x86 assembly kernel. Parts of the kernel have also been redesigned for better portability. Among the goodies added since the last release are: o Small Address Spaces o IPC FastPath(tm) o FPU virtualization o Enhanced kernel debugger (e.g., embedded disassembler and profiling support) o Pentium4 support o One year's worth of bugfixes For more information please visit http://l4ka.org/.

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RE: l4 for 386
by Sebastian Schoenberg 08 Nov '01

08 Nov '01

Well, sort of or not. You have a mirrored region for kernel- accessed read-only memory regions where the kernel potentially might write to. You don't need a mirrored region for all writable pages. Seb > -----Original Message----- > From: Espen Skoglund [mailto:esk@ira.uka.de] > Sent: Mittwoch, 7. November 2001 13:31 > To: Sebastian Schoenberg > Cc: jhuntnz(a)users.sourceforge.net; l4-hackers(a)os.inf.tu-dresden.de > Subject: RE: l4 for 386 > > > [Sebastian Schoenberg] > > This can be done by using different regions for read and write > > access. For tasks where the write-protection is neccesary, a page > > is mapped only to the writeable area if the page is writable in the > > page-table. > > I'm not sure I know what you mean here. Are you suggesting that we > divide the user-accessible virtual memory into two equally sized > mirrored regions; one for read-only and one for read-write? > > eSk >

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RE: l4 for 386
by Sebastian Schoenberg 07 Nov '01

07 Nov '01

This can be done by using different regions for read and write access. For tasks where the write-protection is neccesary, a page is mapped only to the writeable area if the page is writable in the page-table. The task is to find all relevant writes in the current version. Seb > -----Original Message----- > From: Michael Hohmuth [mailto:hohmuth@innocent.com] > Sent: Mittwoch, 7. November 2001 12:35 > To: jhuntnz(a)users.sourceforge.net > Cc: l4-hackers(a)os.inf.tu-dresden.de > Subject: Re: l4 for 386 > > > Jonathan Hunt <jhuntnz(a)users.sourceforge.net> writes: > > > Yes I would but interested in porting this to a 386. Could anyone > > give me some more information on what would be required to > > change. (The FAQ is rather brief). I understand the the CR0::WP bit > > enables an exception when a fully privileged task (such as the > > kernel task) writes to a read-only page but when does this happen > > that I can check explicitly for it? > > Offhand I can think of two places that rely on page faults when > writing to write-protected pages: > > - When reading from a nonexisting thread's thread-control block (TCB), > the TCB's virtual-memory region is backed by a read-only zero-filled > page. This page gets replaced with a newly-allocated page only when > a write access occurs. This mechanism is intended to prevent > malicious threads from causing the kernel to allocate hundreds of > pages by attempting to send IPC to (or otherwise modify) nonexisting > threads. > > In a first 386 version, this protection mechanism can just > be disabled. > > - In memory-copying IPC operations (and some other operations that > write to the user address space, like exception delivery), > the kernel > relies on page faults when accessing write-protected user pages. > > This could be approximated by checking for write permission in the > copy operation, like Linux does. > > Michael > -- > hohmuth(a)innocent.com, hohmuth(a)inf.tu-dresden.de > http://home.pages.de/~hohmuth/ > _______________________________________________ > 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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Re: l4 for 386
by Michael Hohmuth 07 Nov '01

07 Nov '01

Jonathan Hunt <jhuntnz(a)users.sourceforge.net> writes: > Yes I would but interested in porting this to a 386. Could anyone > give me some more information on what would be required to > change. (The FAQ is rather brief). I understand the the CR0::WP bit > enables an exception when a fully privileged task (such as the > kernel task) writes to a read-only page but when does this happen > that I can check explicitly for it? Offhand I can think of two places that rely on page faults when writing to write-protected pages: - When reading from a nonexisting thread's thread-control block (TCB), the TCB's virtual-memory region is backed by a read-only zero-filled page. This page gets replaced with a newly-allocated page only when a write access occurs. This mechanism is intended to prevent malicious threads from causing the kernel to allocate hundreds of pages by attempting to send IPC to (or otherwise modify) nonexisting threads. In a first 386 version, this protection mechanism can just be disabled. - In memory-copying IPC operations (and some other operations that write to the user address space, like exception delivery), the kernel relies on page faults when accessing write-protected user pages. This could be approximated by checking for write permission in the copy operation, like Linux does. Michael -- hohmuth(a)innocent.com, hohmuth(a)inf.tu-dresden.de http://home.pages.de/~hohmuth/

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l4 for 386
by Jonathan Hunt 07 Nov '01

07 Nov '01

Hi, Is there a version of l4 for a Intel 386. I am wanting to experiment with l4 and have a spare i386 to play with but nothing else. None of the "virtual machine" solutions look very nice. If not is anybody working on a version? Any plans? Thanks, Jonny -- Jonathan Hunt (The Real Jonathan Hunt) <jhuntnz(a)users.sf.net> Jabber at jhuntnz(a)jabber.com "He is no fool who gives what he cannot keep to gain what he cannot lose." Jim Elliot

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How to unsubscribe
by Li Bing 05 Nov '01

05 Nov '01

Dear all, Please tell me how to unsubscribe the list. I am very appreciated for your help! LB _.--"""--._ .' '-. `. __/__ (-. `\ \ /o `o \ \ \ \ _\__.__/ )) | | ; .--;" | | \ ( `) | | \ _|`---' .' _, _| | `\ '`_\ \ '_,.-';_.-`\| \ \_ .' '--'---;` / / |\ |_..--' \ \'-'.' .--'.__/ __.-; `"` (___...---''` \ _/_ \ /ASU\ libing(a)asu.edu \___/ 480-965-9038(L), 480-829-8492(H) http://www.public.asu.edu/~libing

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Why distinction between task and thread ?
by Robert Kaiser 05 Nov '01

05 Nov '01

Hello all, this may be a stupid question, but... It seems to me that address spaces and activities (to avoid the words "task" and "thread") are othogal concepts. What is the reason for L4 to not keep them seperate in it's API ? (i.e. there is task_new to create an activity _and_ an address space and there is lthread_ex_regs to create an activity in an already existing address space). It would seem a lot "cleaner" to me if there was one system call to create an address space (without any activity in it) and another one to create an activity, specifying as a parameter the address space in which it will execute. Is there a reason (perhaps security ?) why it wasn't done like that in L4 ? Thanks for any insights. Rob ---------------------------------------------------------------- Robert Kaiser email: rkaiser(a)sysgo.de SYSGO RTS GmbH Am Pfaffenstein 14 D-55270 Klein-Winternheim / Germany fax: (49) 6136 9948-10

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tftp problems
by Ian Duggan 05 Nov '01

05 Nov '01

I'm having problems getting L4 to boot using grub and tftp. My grub config looks like this: title = ChacmOS on Sopwith kernel = (nd)/tftpboot/chacmos/rmgr -sigma0 -roottask module = (nd)/tftpboot/chacmos/x86-kernel module = (nd)/tftpboot/chacmos/sigma0 module = (nd)/tftpboot/chacmos/booter module = (nd)/tftpboot/chacmos/memsvr module = (nd)/tftpboot/chacmos/namesvr module = (nd)/tftpboot/chacmos/ext2fs module = (nd)/tftpboot/chacmos/ramdisk module = (nd)/tftpboot/chacmos/shell It gets as far as retrieving rmgr via tftp (I see it get requested in the logs), but the machine reboots itself as it is loading the rmgr image. It prints out the "[Multiboot-elf blah blah" stuff and does a reboot before anything related to x86-kernel is printed to the screen. This happens very quickly. If I move the first two files to the boot floppy I am using, things boot fine. This config works: title = ChacmOS on Sopwith (Floppy) kernel = (fd0)/rmgr -sigma0 -roottask module = (fd0)/x86-kernel module = (nd)/tftpboot/chacmos/sigma0 module = (nd)/tftpboot/chacmos/booter module = (nd)/tftpboot/chacmos/memsvr module = (nd)/tftpboot/chacmos/namesvr module = (nd)/tftpboot/chacmos/ext2fs module = (nd)/tftpboot/chacmos/ramdisk module = (nd)/tftpboot/chacmos/shell There is something in the grub/tftp boot process that differs from what it does when loading the files from floppy that causes problems. It seems that maybe it is starting to execute stuff before it has everything in place? I am using grub 0.90 from the Debian source. Any ideas? What else can I do to try to track down the problem? --Ian ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ Ian Duggan ian(a)ianduggan.net http://www.ianduggan.net

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Re: vk_l4 -- CVS Setup
by Lars Reuther 30 Oct '01

30 Oct '01

Farid Hajji <farid.hajji(a)ob.kamp.net> writes: > BTW, is anyone in the L4 community currently implementing a pager task > that would resemble Mach-VM or, even better, UVM? This is of general > interest to all developers of L4-based OS-personalities, not just > l4-hurd. Getting all the memory from sigma0 upon startup is not very sexy ;-). The current VM management model of L4Env is roughly based on the ideas described in <ftp://ftp.cse.unsw.edu.au/pub/users/disy/papers/Aron_PJLED_01.ps.gz>. See also the documentations for the L4 Region Mapper and Dataspace Manager at the L4 Developer's Bibliography mentioned by Michael. Lars -- Dipl.-Inf. Lars Reuther Dresden University of Technology Department of Computer Science Operating Systems Research Group Phone: +49 (351) 463-38401 Fax: +49 (351) 463-38284 reuther(a)os.inf.tu-dresden.de http://os.inf.tu-dresden.de/~reuther/

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