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how to build L4android for ARM?
by Jay Yao 24 Jun '12

24 Jun '12

Hi , I'm a rookie. And I'm very interest in L4Android. I want to use L4android in arm platform, but I don't know how to build L4android for arm , is there any build tutorials?

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l4linux build failure, and a few questions
by Ryan Brown 24 Jun '12

24 Jun '12

I tried building l4linux for x86 and got this error: MODPOST vmlinux.o WARNING: modpost: Found 1 section mismatch(es). To see full details build your kernel with: 'make CONFIG_DEBUG_SECTION_MISMATCH=y' GEN .version CHK include/generated/compile.h UPD include/generated/compile.h CC init/version.o LD init/built-in.o LD .tmp_vmlinux1 drivers/built-in.o: In function `pnp_register_irq_resource': /home/ribrdb/fiasco/src/l4linux/drivers/pnp/resource.c:70: undefined reference to `pcibios_penalize_isa_irq' make[1]: *** [.tmp_vmlinux1] Error 1 make: *** [sub-make] Error 2 Has anyone seen this before? Also I had a few questions about configuring l4linux: I see that the paravirtualization options are not supported. Is there a specific reason for this? I'd like to be able to use virtio devices from l4linux when running in a VM. Neither x86_64 or highmem is supported. Is there any way to run an l4 linux with more than 1G of memory? Can 32 bit l4linux run on a 64 bit fiasco kernel? Does 32 bit fiasco support more than 1G of physical memory? What would be involved if I wanted to port l4linux to x86_64? Thanks, and sorry for so many questions. Ryan Brown

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Re: l4-hackers Digest, Vol 110, Issue 18
by Robert Campbell 24 Jun '12

24 Jun '12

> There's one thing to add, though: By running device drivers in dedicated > user-level processes, a crashing driver in the common case only takes > down its own process, but the rest of the system continues to run. > That's a major advantage, because you can have a monitoring process that > then restarts the driver [1] this way. > However, even a user space driver can still crash the system if it goes > rampant by misprogramming the DMA engine and you don't use an IOMMU. > Bjoern Are there plans to provide IOMMU support in Fiasco.OC?

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Keeping track of the CPU time for a thread
by Mohammad A Haque 24 Jun '12

24 Jun '12

Hi, I want to measure how much CPU time a thread has consumed. When the CPU time consumption exceeds a certain limit (specific to that thread), I want to raise an interrupt. Please suggest me how can I do it efficiently? Thanks.

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Re: l4linux GPU direct access
by Abhishek Gupta 21 Jun '12

21 Jun '12

Hi Adam, I was just trying to change the config file of l4linux to enable support for MTRRs because my Xserver log file had a warning (WW) System lacks support for changing MTRRs I was wondering why it is not allowed to enable to support for MTRRs? Below is the complete X.org log file: X.Org X Server 1.7.7 Release Date: 2010-05-04 X Protocol Version 11, Revision 0 Build Operating System: Linux 2.6.32.29-dsa-ia32 i686 Debian Current Operating System: Linux moarhost 3.0.0-l4-svn23 #72 SMP Thu Mar 8 18:05:24 CET 2012 i686 Kernel command line: mem=400M root=/dev/hda Build Date: 19 February 2011 02:37:36PM xorg-server 2:1.7.7-13 (Cyril Brulebois <kibi(a)debian.org>) Current version of pixman: 0.16.4 Before reporting problems, check http://wiki.x.org to make sure that you have the latest version. Markers: (--) probed, (**) from config file, (==) default setting, (++) from command line, (!!) notice, (II) informational, (WW) warning, (EE) error, (NI) not implemented, (??) unknown. (==) Log file: "/var/log/Xorg.0.log", Time: Thu Jan 1 00:00:27 1970 (==) Using system config directory "/usr/share/X11/xorg.conf.d" (==) No Layout section. Using the first Screen section. (==) No screen section available. Using defaults. (**) |-->Screen "Default Screen Section" (0) (**) | |-->Monitor "<default monitor>" (==) No monitor specified for screen "Default Screen Section". Using a default monitor configuration. (==) Automatically adding devices (==) Automatically enabling devices (WW) The directory "/usr/share/fonts/X11/misc" does not exist. Entry deleted from font path. (WW) The directory "/usr/share/fonts/X11/cyrillic" does not exist. Entry deleted from font path. (WW) The directory "/usr/share/fonts/X11/100dpi/" does not exist. Entry deleted from font path. (WW) The directory "/usr/share/fonts/X11/75dpi/" does not exist. Entry deleted from font path. (WW) The directory "/usr/share/fonts/X11/Type1" does not exist. Entry deleted from font path. (WW) The directory "/usr/share/fonts/X11/100dpi" does not exist. Entry deleted from font path. (WW) The directory "/usr/share/fonts/X11/75dpi" does not exist. Entry deleted from font path. (WW) The directory "/var/lib/defoma/x-ttcidfont-conf.d/dirs/TrueType" does not exist. Entry deleted from font path. (==) FontPath set to: built-ins (==) ModulePath set to "/usr/lib/xorg/modules" (II) The server relies on udev to provide the list of input devices. If no devices become available, reconfigure udev or disable AutoAddDevices. (II) Loader magic: 0x81ecca0 (II) Module ABI versions: X.Org ANSI C Emulation: 0.4 X.Org Video Driver: 6.0 X.Org XInput driver : 7.0 X.Org Server Extension : 2.0 (--) using VT number 7 (--) PCI:*(0:0:1:0) 1234:1111:1af4:1100 Technical Corp. rev 0, Mem @ 0xf0000000/16777216 (WW) Open ACPI failed (/var/run/acpid.socket) (No such file or directory) (II) LoadModule: "extmod" (II) Loading /usr/lib/xorg/modules/extensions/libextmod.so (II) Module extmod: vendor="X.Org Foundation" compiled for 1.7.7, module version = 1.0.0 Module class: X.Org Server Extension ABI class: X.Org Server Extension, version 2.0 (II) Loading extension SELinux (II) Loading extension MIT-SCREEN-SAVER (II) Loading extension XFree86-VidModeExtension (II) Loading extension XFree86-DGA (II) Loading extension DPMS (II) Loading extension XVideo (II) Loading extension XVideo-MotionCompensation (II) Loading extension X-Resource (II) LoadModule: "dbe" (II) Loading /usr/lib/xorg/modules/extensions/libdbe.so (II) Module dbe: vendor="X.Org Foundation" compiled for 1.7.7, module version = 1.0.0 Module class: X.Org Server Extension ABI class: X.Org Server Extension, version 2.0 (II) Loading extension DOUBLE-BUFFER (II) LoadModule: "glx" (II) Loading /usr/lib/xorg/modules/extensions/libglx.so (II) Module glx: vendor="X.Org Foundation" compiled for 1.7.7, module version = 1.0.0 ABI class: X.Org Server Extension, version 2.0 (==) AIGLX enabled (II) Loading extension GLX (II) LoadModule: "record" (II) Loading /usr/lib/xorg/modules/extensions/librecord.so (II) Module record: vendor="X.Org Foundation" compiled for 1.7.7, module version = 1.13.0 Module class: X.Org Server Extension ABI class: X.Org Server Extension, version 2.0 (II) Loading extension RECORD (II) LoadModule: "dri" (II) Loading /usr/lib/xorg/modules/extensions/libdri.so (II) Module dri: vendor="X.Org Foundation" compiled for 1.7.7, module version = 1.0.0 ABI class: X.Org Server Extension, version 2.0 (II) Loading extension XFree86-DRI (II) LoadModule: "dri2" (II) Loading /usr/lib/xorg/modules/extensions/libdri2.so (II) Module dri2: vendor="X.Org Foundation" compiled for 1.7.7, module version = 1.1.0 ABI class: X.Org Server Extension, version 2.0 (II) Loading extension DRI2 (==) Matched vesa as autoconfigured driver 0 (==) Matched fbdev as autoconfigured driver 1 (==) Assigned the driver to the xf86ConfigLayout (II) LoadModule: "vesa" (II) Loading /usr/lib/xorg/modules/drivers/vesa_drv.so (II) Module vesa: vendor="X.Org Foundation" compiled for 1.7.7, module version = 2.3.0 Module class: X.Org Video Driver ABI class: X.Org Video Driver, version 6.0 (II) LoadModule: "fbdev" (II) Loading /usr/lib/xorg/modules/drivers/fbdev_drv.so (II) Module fbdev: vendor="X.Org Foundation" compiled for 1.7.6.901, module version = 0.4.2 ABI class: X.Org Video Driver, version 6.0 (II) VESA: driver for VESA chipsets: vesa (II) FBDEV: driver for framebuffer: fbdev (II) Primary Device is: PCI 00@00:01:0 (WW) Falling back to old probe method for fbdev (II) Loading sub module "fbdevhw" (II) LoadModule: "fbdevhw" (II) Loading /usr/lib/xorg/modules/linux/libfbdevhw.so (II) Module fbdevhw: vendor="X.Org Foundation" compiled for 1.7.7, module version = 0.0.2 ABI class: X.Org Video Driver, version 6.0 (II) Loading sub module "vbe" (II) LoadModule: "vbe" (II) Loading /usr/lib/xorg/modules/libvbe.so (II) Module vbe: vendor="X.Org Foundation" compiled for 1.7.7, module version = 1.1.0 ABI class: X.Org Video Driver, version 6.0 (II) Loading sub module "int10" (II) LoadModule: "int10" (II) Loading /usr/lib/xorg/modules/libint10.so (II) Module int10: vendor="X.Org Foundation" compiled for 1.7.7, module version = 1.0.0 ABI class: X.Org Video Driver, version 6.0 (II) VESA(0): initializing int10 (WW) System lacks support for changing MTRRs (II) VESA(0): Primary V_BIOS segment is: 0xc000

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L4 Driver Security
by Tobias Fink 20 Jun '12

20 Jun '12

Hey List, me again with one (hopefully final) question. I'm learning about Driver Security in L4Re. I have some statements which I would like to have confirmed to understand the underlying principles: 1. L4 Drivers use DMA and are therefore able to write directly to the device memory and thus can cause crashes or damage if not carefully implemented. 2. While the L4Re Io-Server manages the access of drivers to the hardware's address spaces, it doesn't prevent drivers to write "bad" things into the device memory. 3. Untrusted, untested drivers can cause system crashes. best regards Tobi

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Re: l4linux GPU direct access
by Abhishek Gupta 19 Jun '12

19 Jun '12

Hi Adam, Where can I add x86emu inside L4Linux to switch modes??

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Re: L4Android on Pandaboard
by Matthias Lange 19 Jun '12

19 Jun '12

On 19.06.2012, at 15:49, ZhangEditing wrote: > android_bus => new System_bus() > { > sys => wrap(hw-root.sys); > prcm => wrap(hw-root.prcm); > sysdma => wrap(hw-root.sysdma); > gic => wrap(hw-root.gic); > hsmmc1 => wrap(hw-root.hsmmc1); > hsmmc2 => wrap(hw-root.hsmmc2); > hsmmc3 => wrap(hw-root.hsmmc3); > hsmmc4 => wrap(hw-root.hsmmc4); > hsmmc5 => wrap(hw-root.hsmmc5); > } The gic shouldn't be assigned to L4Android as it is driven by Fiasco. > In addition, I don't know how to assign registers that affect global configuration of the platform (e.g., the system control registers), although I don't think it is appropriate to assign such registers to only one OS. You can write a L4Re server which configures those registers. Then L4Android can access those registers via the server interface. Matthias. -- Dipl.-Inf. Matthias Lange <mlange(a)sec.t-labs.tu-berlin.de> Security in Telecommunications TU Berlin / Deutsche Telekom Laboratories Ernst-Reuter-Platz 7, 10587 Berlin Phone: +49 - 30 - 8353 58 553 Mobile: +49 - 160 - 587 28 07 Web: http://www.t-labs.tu-berlin.de/sect

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Re: L4Android on Pandaboard
by Matthias Lange 19 Jun '12

19 Jun '12

On 18.06.2012, at 02:59, ZhangEditing wrote: > > You should have a look into the Pandaboard TRM and gather the right MMIO regions needed for MMC etc. Then connect those to the vbus for the L4Android kernel. > > I tried to do so, but L4Android recognizes only SDHCI. Maybe I still missed something. > Are there resources other than MMIO regions and IRQs that have to be configured for the I/O server? Probably you need some GPIO pins. Have a look into the Pandaboard TRM. Matthias. -- Dipl.-Inf. Matthias Lange <mlange(a)sec.t-labs.tu-berlin.de> Security in Telecommunications TU Berlin / Deutsche Telekom Laboratories Ernst-Reuter-Platz 7, 10587 Berlin Phone: +49 - 30 - 8353 58 553 Mobile: +49 - 160 - 587 28 07 Web: http://www.t-labs.tu-berlin.de/sect

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Re: l4-hackers Digest, Vol 110, Issue 14
by Abhishek Gupta 18 Jun '12

18 Jun '12

Hi Adam, Where should I add x86emu inside L4Linux to switch modes??

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L4Android on Pandaboard
by ZhangEditing 17 Jun '12

17 Jun '12

Hello, everyone! I'm new to L4Android and I'm interested in running L4Android on Pandaboard (OMAP4430). I tried to pack the system image of Android userland together with the kernel into a single U-image, but Pandaboard cannot finish loading the U-image. If the system image of Android userland is not included in the U-image, Pandaboard is able to load the U-image and boot the kernel. So I unpacked the system image to a separate partition on the SD card and I'm now trying to make L4Android use the partition. However, L4Android does not seem to recognize the entire SD card. There is no MMC devices under /dev/block. Instead, only 15 ram devices and 1 l4bdds device are there. I'm not sure whether L4Android has the right driver for SD card-related devices on Pandaboard. On the other hand, since I'm not familiar with Pandaboard, I don't know if I'm using the right device configuration (in the form of a .devs file) for the I/O server of L4Re. Could anyone help? Does anyone have a suitable .devs file for Pandaboard OMAP4430? Thank you in advance!

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Re: l4linux GPU direct access
by Abhishek Gupta 16 Jun '12

16 Jun '12

Hi Adam, Thanks for your suggestion. We tried what you suggested and it worked. But that's not what we want. We want Graphics Acceleration and use vesa framebuffer. How can I make sure that int10 is passed to the l4linux by l4 and executes int10 module successfully.

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adding libraries to L4/fiasco & L4re
by smkim 15 Jun '12

15 Jun '12

Hi hackers. I have questions about adding additional libraries for L4/fiasco & L4re. I tried to find some documents about it, but I failed. My question is Is there any guildlines which explains the process how to port additional libaries in L4/fiasco & L4re? If not, I hope you to suggest the way to solve it. What I wanna port is OpenCV. Best regards, Seongmin Kim.

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IPC between Tasks
by Tobias Fink 15 Jun '12

15 Jun '12

Hi, I'm planning on building a small example of a producer/consumer build on top of L4Re. From the documentation I know about the shared memory inteface which will help to pass information from the producer to the consumer but I am a bit clueless on how I notify the consumer that there is something new to read. The semaphore is only to be used in between threads so there is no way to use them for IPC between Tasks?! Is there another possibility to make this work other than to use polling? regards Tobi

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Connect two devices to vbus
by Pierre Larus 13 Jun '12

13 Jun '12

Hi, In my project, I have defined two io memory ressources as devices. I want connect these two devices to vbus. "io_bus.gpt2" is actually connected to vbus. But is it possible to also connect "io_bus.intc" to vbus ? local name = "l4rtos"; local DeviceFile = "beagle.devs" local IOFile = "beagle.io" local loader = L4.default_loader; local io_bus = { gpt2 = loader:new_channel(); intc = loader:new_channel(); }; loader:start({ caps = { gpt2 = io_bus.gpt2:svr(), intc = io_bus.intc:svr(), icu = L4.Env.icu, sigma0 = L4.cast(L4.Proto.Factory, L4.Env.sigma0):create(L4.Proto.Sigma0), }, }, "rom/io rom/" .. DeviceFile .. " rom/" .. IOFile); loader:start( { caps = { vbus = io_bus.gpt2, icu = L4.Env.icu, log = L4.Env.log:m("rws"), }, }, "rom/" .. name); Regards, Pierre Larus

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porting file system for L4/fiasco & L4re
by mkmaeng 13 Jun '12

13 Jun '12

Hello everyone. I have questions about using file system for L4/fiasco & L4re. I tried to convert applications using file I/O to L4 environment but I failed. So I realized that I need to use file system in L4/fiasco, but I couldn't find any documents about it. I have two questions. 1. How can I put root file system on L4/fiasco? Are there any references or documents that I can refer? 2. How can I verify whether file system is working or not. Are there any libraries for L4 to use file I/O? I hope you to suggest direction to solve this problems for me. Thank you very much. Best regards, Minkyu Maeng.

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I have a question about l4linux
by Ednilson Ricardo 11 Jun '12

11 Jun '12

Hello, I would like to know what forms of input and output data L4Linux. thank you

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porting file system for L4/fiasco & L4re
by mkmaeng 11 Jun '12

11 Jun '12

Hello everyone. I have questions about using file system for L4/fiasco & L4re. I tried to convert applications using file I/O to L4 environment but I failed. So I realized that I need to use file system in L4/fiasco, but I couldn't find any documents about it. I have two questions. 1. How can I put root file system on L4/fiasco? Are there any references or documents that I can refer? 2. How can I verify whether file system is working or not. Are there any libraries for L4 to use file I/O? I hope you to suggest direction to solve this problems for me. Thank you very much. Best regards, Minkyu Maeng.

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l4 linux questions
by Ryan Brown 11 Jun '12

11 Jun '12

The l4 linux page doesn't have much information about the l4re version of l4 linux. How stable is it? What is the performance like? Is there any way to mount the l4re VFS inside linux? I was thinking perhaps I could mount it using 9p to an l4 server. But it looks like 9p needs tcp/ip. Is there a way I can use something like l4shmnet to talk to an l4 server instead of talking to another l4linux?

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Hardware irq and vcpu entry
by Pierre Larus 11 Jun '12

11 Jun '12

Hi I am porting an RTOS on L4RE. The RTOS run in a l4_thread and I am currently trying to handle hardware timer irq. I would like to know if it is possible to attach an hardware irq (timer irq) to a vcpu entry ? I try to do this in a vpcu thread: vcpu_state->state = L4_VCPU_F_EXCEPTIONS | L4_VCPU_F_IRQ; vcpu_state->entry_ip = (l4_addr_t)&vcpu_entry; vcpu_state->user_task = L4_INVALID_CAP; InitClockDevice(); icucap = l4re_get_env_cap("icu"); irqcap = l4re_util_cap_alloc(); l4_factory_create_irq(l4re_global_env->factory, irqcap); l4_icu_bind(icucap, 38, irqcap); l4_irq_attach(irqcap, 0x38, current_thread_cap); StartUpMain(); But this solution does not work. The thread vcpu support works because when I use the l4_irq_trigger() function the irq are catched by the vcpu entry. The irq attach also works because I can handle hardware interrupt using a dedicated thread: icucap = l4re_get_env_cap("icu"); irqcap = l4re_util_cap_alloc(); l4_factory_create_irq(l4re_global_env->factory, irqcap); l4_icu_bind(icucap, 38, irqcap); l4_irq_attach(irqcap, 0x38, current_thread_cap); while (1) { l4_irq_receive(irqcap, L4_IPC_NEVER); isr_handler(); } Regards, Pierre LARUS

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l4linux GPU direct access
by Abhishek Gupta 07 Jun '12

07 Jun '12

Hi, I was trying to run xserver on l4linux using vesa frame buffer (l4 is running on kvm) and virtual machine hangs and it seems that a infinite loop is started which is continuously try to do something but doesn't succeed. When I tried to debug it using gdb, it displays 0xb6ee9b28 in SetResetBIOSVars (pInt=0x820f5a0, set=<value optimized out>) at ../../../../hw/xfree86/int10/helper_exec.c:686 this code is from the xserver 1.7.7 static void SetResetBIOSVars(xf86Int10InfoPtr pInt, Bool set) { int pagesize = getpagesize(); unsigned char* base = xf86MapVidMem(pInt->scrnIndex, VIDMEM_MMIO, 0, pagesize); int i; if (set) { for (i = BIOS_SCRATCH_OFF; i < BIOS_SCRATCH_END; i++) MEM_WW(pInt, i, *(base + i)); } else { for (i = BIOS_SCRATCH_OFF; i < BIOS_SCRATCH_END; i++) /*line 685*/ *(base + i) = MEM_RW(pInt, i); /*line 686*/ //This line of code is not working } xf86UnMapVidMem(pInt->scrnIndex,base,pagesize); } The value of base becomes 0 after xf86MapVidMem func is called. So my Guess is that this func is failing and returning NULL but I am not able to figure out why Also I read in previous years mailing list that Linux tries to execute int10 to set the VESA mode but L4 applications are not allowed to execute real-mode code. Does this have anything to do with my problem?? How can I fix this problem? Also, Is there a way to allow L4 applications to execute code in real mode and then switch back? May be add some code to L4 to allow applications to execute code in real mode and then switch back. Abhishek Gupta Indian School of Mines

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Fiasco.OC: sigma0 stucks in ipc-path
by Stefan kalkowski 07 Jun '12

07 Jun '12

Dear kernel-hackers, I think I came along a problem in the IPC-path of Fiasco.OC sometimes in the past, but it was somehow hard to reproduce. But now I've an example that quite reliable triggers the issue. The symptom in the past, and in the concrete example was that our roottask in Genode (called core) was requesting memory from sigma0, either implicitly just by touching some memory-area, like a ROM-module loaded by the bootloader, or explicitly by using the sigma0-protocol, e.g. to request I/O memory for the framebuffer. After that the request was received by sigma0, and also processed, but the answer never reached the faulter/client in this case the core-pager thread. The typical picture in the kernel-debugger then looks like the following: http://pastebin.com/cFvn1NV2 sigma0 is marked as ready, but it still stucks in the ipc-syscall. By instrumenting the kernel I could break down the point where sigma0 never returns. It is when trying to establishing the actual mapping in 'Thread::transfer_msg_items' in file src/kern/thread-ipc.cc. The spot is the following: ``` cpu_lock.clear(); L4_error err = fpage_map(snd->space(), sfp, rcv->space(), L4_fpage(buf->d), item->b, &rl); cpu_lock.lock(); ``` After the cpu lock is given away, sigma0 never aquires it back successfully. It looks to me like a race-condition, nevertheless simply letting the lock being locked doesn't solved the problem ;-). Maybe given your insight knowledge, you're much faster in tracking the problem down to its root? I've to add, that the problem occurred on x86 as well as ARM, on different QEMU versions, as well as real hardware. I also could reproduce it with slightly older versions of Fiasco.OC, and in different development stages of Genode. Nevertheless, it was never that reliable to reproduce. The current example which reproduces it reliable at least with my QEMU (qemu-kvm-0.14.0) version. You can find in form of an ISO-image here: http://dl.dropbox.com/u/82567292/avplay.iso You can try the iso-image like the following: qemu -no-kvm -m 256 -soundhw all -serial mon:stdio -cdrom avplay.iso Or, if you've to build it on your own, here is my topic branch, including the avplay run-script that triggers the problem: https://github.com/skalk/genode/tree/fiasco.oc-ipc-issue To compile and run it yourself you've to do the following steps (after installing the genode toolchain from http://genode.org/download/tool-chain) git clone git@github.com:skalk/genode.git cd genode git checkout -b issue origin/fiasco.oc-ipc-issue git clone git@github.com:genodelabs/linux_drivers.git make -C base-foc prepare make -C libports prepare PKG="libav libc sdl zlib" tool/create_builddir foc_x86_32 BUILD_DIR=build sed -i "/#REPOSITORIES.*libports/s/#//" build/etc/build.conf sed -i "/#REPOSITORIES.*linux_drivers/s/#//" build/etc/build.conf make -C build run/avplay Thank you in advance & best regards! Stefan

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[l4ankh] Problems with fixed l4ankh
by Timur 03 Jun '12

03 Jun '12

Hi! I had fixed the l4ankh driver and after that it started to work properly. Now only thread is used to receive packets. In lines 158-162 we clear the rcv buffer: that is necessary to be done as after opening a session we start to receive packets that should not be served; otherwise the response time will be quite slow. This is not the best solution, but I do not have time to make it better. Now I face the following problem: the driver in ankh (I use 8139cp) stops receiving packets after some time (for me it is usually 3-4 minutes). This situation occurs when the interrupt handler was called and the device register IntrStatus already equals "zero". An interrupt doesn't work after that. -- Galiullin Timur

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I have a question about L4Linux
by Ednilson Ricardo 03 Jun '12

03 Jun '12

Hello, I have some doubts about the L4Linux, can you help me? *** What are the purposes of L4Linux?Hardware subjaecnte that OS (capacity and types of memory, processor, bus, etc.).*** With this operating system can work? What capacity and type of hardware it runs? What is the architecture that it needs to function? the type of memory itworks? processors that it works, buses, and everything involved in the operating system. What it needs hardware to run? What type of application it serves?Interaticas, batch, real-time, etc..*** What are the characteristics related to the accomplishment of the application,low response time, low turnaround time, etc.. (View aqielas applications, which it meets the requirements) as it meets these requirements? -> It is otimisado,blibioterca specific uses, he uses some dynamic code that allows it meets these requirements, then how it will work.*** What is your architecture? (Monolithic? Layered? Micro-kernel virtual machineor some other system) PREFERENCE TO EXPLAIN AND THE GREATERLEVEL POSSIBLE to detail.*** If the operating system is not supposed or threads (the core of User, hybrid?)And how the theads are implemented in the OS (if it meets it has a mechanism forimplementation (How it was implemented)

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Debugging l4linux + l4re
by Haohui Mai 03 Jun '12

03 Jun '12

Hi folks, I'm running mag + L4Linux on a real machine that doesn't have a serial port. It's really difficult to debug -- I'm wondering if there're any ways to open a new window under mag, and to redirect all serial port I/O to that window? It would be really helpful for debugging. I appreciate if anyone could share if he happens wrote this program before, or giving me some suggestions. Your help is appreciated! ~Haohui

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