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Re: l4/log/l4log.h
by Michael Hohmuth 20 May '00

20 May '00

Juho Östman <jostman(a)myrealbox.com> writes: > It seems that the file 'l4log.h' is missing in the CVS distribution. > Where is it found? I have added the "log" package to the CVS distribution. (We recently introduced a dependency on the "log" package in the code we distribute; I think there even are some cross dependencies between packages... the easy fix for now just seems to be distributing the "log" package as well. :-) Michael -- hohmuth(a)innocent.com, hohmuth(a)inf.tu-dresden.de http://home.pages.de/~hohmuth/

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l4/log/l4log.h
by Juho Östman 15 May '00

15 May '00

It seems that the file 'l4log.h' is missing in the CVS distribution. Where is it found?

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Re: Plaese .. Could you help me ?
by Michael Hohmuth 14 Apr '00

14 Apr '00

Ricky, Jean just went into his well-deserved weekend, but he told me to tell you that he has tried your boot disk, and has been able to reproduce your problem. He got it to run by replacing your Fiasco binary with a newer version of Fiasco. So you are probably using an outdated version of the kernel. You should download a newer version from our remote-CVS server (see <URL:http://os.inf.tu-dresden.de/drops/download.html for instructions). Michael Jean Wolter <jean.wolter(a)inf.tu-dresden.de> writes: > "Ricky(Soohyung) Lee" <onlyjazz(a)cselab.snu.ac.kr> writes: > > > But, I have another problem. > > When I boot from the grub floppy disk with glinux.gz on it, > > after the message that is saying the first task is created, > > the kernel fall into the endless loop with printing out " root: rcvd > > b9002, 4bc10c, src :5.3 ". > > Would it be possible to gzip the boot disk and send it to us? Then we > could try to boot it and see, what fails. > > I´m not quite sure that I understand the scenario good enough to come > up with an explanation and a fix. Somehow the service thread (5.3) > touches a page in the adapter area (a0000-100000) and doesn´t get or > doesn´t have a mapping for it. > > Jean -- hohmuth(a)innocent.com, hohmuth(a)inf.tu-dresden.de http://home.pages.de/~hohmuth/

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Re: Plaese .. Could you help me ?
by Jean Wolter 14 Apr '00

14 Apr '00

"Ricky(Soohyung) Lee" <onlyjazz(a)cselab.snu.ac.kr> writes: > But, I have another problem. > When I boot from the grub floppy disk with glinux.gz on it, > after the message that is saying the first task is created, > the kernel fall into the endless loop with printing out " root: rcvd > b9002, 4bc10c, src :5.3 ". Would it be possible to gzip the boot disk and send it to us? Then we could try to boot it and see, what fails. I´m not quite sure that I understand the scenario good enough to come up with an explanation and a fix. Somehow the service thread (5.3) touches a page in the adapter area (a0000-100000) and doesn´t get or doesn´t have a mapping for it. Jean -- I get up each morning, gather my wits. Pick up the paper, read the obits. if I'm not there I know I'm not dead. So I eat a good breakfast and go back to bed. Peete Seeger

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Plaese .. Could you help me ?
by Ricky(Soohyung) Lee 14 Apr '00

14 Apr '00

Hi, everyone ! First of all, let me introduce myself . My name is Ricky Lee . I'm in the course of master's degree at Seoul National University in Korea. Thesedays I'm reading L4-related papers. And, I'm trying to make experience on L4Linux on Fiasco. But, It is not so easy for me. Today, I finally succeeded in building linux22. I really appreciate Michael Hohmuth' advices. But, I have another problem. When I boot from the grub floppy disk with glinux.gz on it, after the message that is saying the first task is created, the kernel fall into the endless loop with printing out " root: rcvd b9002, 4bc10c, src :5.3 ". I guess that it is printed out from root_pager() in l4_paper.c Can you tell me what's wrong ? And, then, what should I do? I really need to solve this problem. So, I really need your help. Please, Help me .. Thanks for your kindness . Thanks . P.S. I compiled Fiasco and Linux22 server on the Redhat package 5.2. Its kernel version is 2.0.36. Any software requirement that is mentioned in the L4linux homepage was met, I think . Can there be the reason of problem with the linux environment in which I compiled those sources ? Can anyone tell me the kernel version and H/W spec. on which you've built the L4Linux22 Server ? It'll be very helpful to me if you tell me them .. Please !!! Thank you very much !! - Ricky Lee -

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IPC & invalid Thread-ID
by Christian Stueble 03 Mar '00

03 Mar '00

-----BEGIN PGP SIGNED MESSAGE----- Hello, what happens if IPC uses an invalid thread-id? Is the message although forwarded to the subsystem's chief? Ciao, Chris -- -=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=- Christian Stueble............stueble(a)ls6.cs.uni-dortmund.de PubKey[BF7104F5].......fp=8678C5D3CAD9CD8C F1DDB8EC202F116A To be or not to be is true... (apocrypha of George Boole) -=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=- -----BEGIN PGP SIGNATURE----- Version: PGPfreeware 5.0i for non-commercial use MessageID: J7gRC3CpAZgh3vXKJpAlEFSfZz45w/ET iQCVAwUBOL5y5fyJjJy/cQT1AQFaywQAhBB4KcN8eHZXMrAPgrvJyQhbEMoRYc6j Wmpt5tBK3Tu1DmcNtTqlcGChzFIDrUiE6+Iw8eN74Bx2Dn+Cn+ohcUmSeaxEjkNl 2F8rTA/13dm/4wojmRz87uAvHWuFx+PycsXm7P3BRRqb+9aC+O1ftau6bNSqsmXC 8A/QvdUxDQg= =PFys -----END PGP SIGNATURE-----

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autoconf
by Juho Östman 28 Feb '00

28 Feb '00

What do you think about adapting L4 (and Fiasco) to use autoconf? The most important immediate benefits are the possibility of using a separate build directory and configuration options. And it would be more compatible with GNU build mechanisms. If you think that is a good idea I could be voluntary to make necessary changes.

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What happened to AIM?
by Gernot Heiser 21 Feb '00

21 Feb '00

Does anyone know what happened to AIM Technology? Their website, www.aim.com, seems to have vanished from the face of the earth. Gernot -- Gernot Heiser ,--_|\ School of Computer Sci. & Engin. Phone: +61 2 9385 5156 / \ The University of NSW Fax: +61 2 9385 5533 \_,--._* Sydney, Australia 2052 E-mail: gernot(a)unsw.edu.au v http://www.cse.unsw.edu.au/~gernot PGP fingerprint: 94 1E B8 28 25 FD 7C 94 20 10 92 E5 0B FF 39 8F

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A few things I'd like to ask
by Juho �stman 04 Feb '00

04 Feb '00

I have become quite familar with L4/x86 Reference manual and L4 User manual (for MIPS) but I think they don't give enough information about designing and writing programs on to the L4 architecture. In my opinion they are a bit unclear and incomplete. Therefore I'd like to ask some questions on that subject. What kind of address space do the initial servers get? I know that sigma0 has the complete physical address space idempotently mapped but what about others? What pages do they have initially mapped? I have understood that the kernel isn't able to free memory it has allocated. Is that true? How is the destination address of an intercepted IPC delivered to the chief? What is sigma1? What should it do? Is sigma0 able to map memory above 0x40000000? How? What happens when the version numbers of a task are used up? Could they be reused? Could tasks donate interrupts like they can donate task numbers? Thanks for everyone who bothers to answer.

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Re: Protected mode I/O driver architecture (Fiasco)
by Michael Hohmuth 28 Jan '00

28 Jan '00

John Nagle <nagle(a)animats.com> writes: > Once I/O flexpages are in, RMGR will be able to issue access to > device space byte by byte. That's right. > It can connect up interrupts to drivers now. Small correction: L4 currently has no interface for safely passing an interrupt assignment. All Rmgr can do when a driver asks for an interrupt is release its attachment so that the driver can attach. This opens a time window for a malicious process racing with the driver to steal the attachment. > The remaining big security problem is DMA. Of course, DMA will be restricted to processes having access to the ports controlling the DMA controller. > In most systems, device drivers are given total access to DMA > controllers. Could that be avoided, with a trusted process that > handles the DMA controllers at the request of the device drivers? > > I'm going to concentrate on PCI bus issues, since ISA is > on the way out and SCSI, USB, and IEEE-1394 devices usually work > through a PCI controller. > > For most devices, DMA is performed by DMA controllers in the > core chipset (such as the Intel 82810), not by the peripherals > themselves. It's seems to be possible to disable the ability of a > PCI device to become a bus master without disabling the ability > of the DMA controllers to execute memory and PCI bus cycles, > at least with the more modern core chipsets. > > So it ought to be possible to have a trusted process that > handles DMA and deals with the memory mapping issues. This > process would be used by device drivers that need DMA. Drivers > would not have access to the DMA controllers directly and would > be untrusted. Yes, all that is correct. A different solution would be to simply trust device drivers also. > There's the related issue of hardware discovery, or > "plug and play". Something is needed at startup to discover > all the hardware, build the hardware tree, and parcel out > hardware resources to drivers. What's planned in that area? We plan to do all this in a device-managing component. As a start, Uwe Dannowski already has added some enhancements to Rmgr that discovers PCI devices and remaps their memory-mapped I/O ports so that only one device has ports in a given high-memory superpage, enabling access control to memory-mapped I/O ports for device drivers. However, I think his changes are currently not available publicly. :( Other than that, not much has been done so far in this area. All drivers currently contain their own PCI-device-discovery code. > Is this consistent with the thinking of the L4/Fiasco/Drops > groups? If not, is there something wrong here? I think you ate pretty much inline with our thinking. Regards, Michael -- hohmuth(a)innocent.com, hohmuth(a)inf.tu-dresden.de http://home.pages.de/~hohmuth/

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