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Using Trustzone on mx53 and L4Linux
by panton 21 Nov '13

21 Nov '13

Hello Hackers, I am trying to run the example on l4/examples/sys/vm-tz on my imx53 qsb. I get something running but I am pretty sure it is not correct. I have found a message called "Full virtualization with Trustzone" that make me wonder several questions and I hope you can help me. 1- The vm-tz example is supposed to run a L4Linux on NS world. What I don't understand in which format should be the linux-image (or any other app you want to run). I use a gz compress linux image (the same I use for running "L4Linux ARM" example), but I think it should be a bin file (not even a ELF). 2- The vm-tz example make use of l4sigma0_map_iomem() to request a memory mapping, but why not a l4sigma0_map_mem() if what you want is RAM mapping? The serial exit I get is: SIGMA0: Dump of all resource maps RAM:------------------------ [0:70000000;70000fff] [0:70063000;7008ffff] [0:70097000;70097fff] [0:7009f000;7013ffff] [4:70140000;7016cfff] [0:7016d000;7016ffff] [4:70170000;70186fff] [0:70187000;7100cfff] [4:7100d000;7100dfff] [0:7100e000;710fffff] [4:71100000;7182cfff] [0:7182d000;8effffff] IOMEM:---------------------- [0:0;6fffffff] [0:90000000;ffffffff] MOE: Hello world MOE: found 499832 KByte free memory MOE: found RAM from 70000000 to 8f000000 MOE: allocated 496 KByte for the page array @0x7009f000 MOE: virtual user address space [0-bfffffff] MOE: rom name space cap -> [C:501000] BOOTFS: [716eb000-71704494] [C:503000] l4re BOOTFS: [71705000-7171e674] [C:504000] vm-tz BOOTFS: [7171f000-7182c73c] [C:505000] io BOOTFS: [71100000-711000bd] [C:506000] arm-rv.io BOOTFS: [71101000-713ea4b4] [C:507000] vmlinuz.arm (My gz compressed linux image) BOOTFS: [713eb000-716eb000] [C:508000] ramdisk-arm.rd MOE: cmdline: moe --init=rom/vm-tz MOE: Starting: rom/vm-tz MOE: loading 'rom/vm-tz' And next is repeated forever without change. VM run VM exit pc:20007000 cpsr:00000013 r0:00000000 r1:0000033b r2:20007100 r3:00000000 r4:00000000 r5:00000000 r6:00000000 r7:00000000 r8:00000000 r9:00000000 r10:00000000 r11:00000000 r12:00000000 lr_svc:00000000 sp_svc:00000000 spsr_svc:00000000 Thanks in advanced for your answers, if any :). Pablo Anton.

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Cons
by Daniel Müller 11 Nov '13

11 Nov '13

Hi, Can someone please explain in a few sentences what the purpose of the cons application (l4/pkg/cons) is? Is it (just) a multiplexer for output? Thanks, Daniel

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question about process generation
by Alexander Aring 08 Nov '13

08 Nov '13

Hi all, I like to implement two processes(if this is the correct word for l4). I want to implement two elf binaries, each of them have a main function. These two processes should communicate over IPC. Is this possible? I have in my modules.list: entry krusty kernel fiasco -serial_esc roottask moe rom/krusty.cfg module foo ... so my init process is 'moe' which should start one than more processes, how can I do that if it possible? In l4 examples of 'ipc' I only saw solution with threads, is this the correct way to initiate new processes? - Alex

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about the snd-base/hot-spot of flexpage mapping
by 冯希顺 07 Nov '13

07 Nov '13

hello everbody. I have a question about the snd-base/hot-spot of flexpage mapping feature. in many l4 documents, there are a lot of words about the snd-base/hot-spot concept, it seem that are a complex mechanism to calculate the send base when the sender's flexpage have different size compares to receiver's flexpage, I have read a lot of documents(l4 user manual/l4 reference manual etc.) about this mechanism, but I can not figure out it... Could you tell why l4 needs this mechanism, and what situation that this mechanism adapt to? And I have another question to Dresden University guys: what is the l4 version of Fiasco.OC based? Thank for your help! Naus

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some question bout L4 memory management
by yakijahn 07 Nov '13

07 Nov '13

Hello L4 hackers Now a days I am studying the memory manage Mechanisms of fiasco kernel and L4RE, and I have some questions: 1) I see that when a process need some memory, a dataspace will be invoked and MOE will retrieve pages from alloc_list as kernel mapping sender, and attach region to region map. if process free a region of memory , the region will be dettached from region map and link the memory back to alloc_list, right? The problem I hold is when and how memory be recycled when a process terminated ? Cause I didn't see system use alloc_list :: free() function when a process had ended, in the process I malloc() about 1 MB memory and didn't free them, but it seems that the memory pre-allocated not been link back to alloc list, could you please tell me when and how will system recycle these memory? If possible, please tell me which code folders is it there. 2) Could you please tell me where are codes(files) that responsible for process virtual memory space management, such as how vitual address be assigned to a variable or pointer. Sometimes i fell to an unhandled page fault when I free pointers, because the page fault address cant be find in region map. Thank you very much for kindly answering Best Reguard YuFen Chang National Tsing-Hua University

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Fiasco.OC API documentation
by Neal H. Walfield 27 Oct '13

27 Oct '13

Hi, I'm looking for documentation on Fiasco.OC's API. I started here: http://os.inf.tu-dresden.de/fiasco/doc.html This led me to this page: http://os.inf.tu-dresden.de/L4Re/doc/ This is mostly a theory page with some links to C++ API documentation, e.g.: http://os.inf.tu-dresden.de/L4Re/doc/group__l4__ipc__api.html Where should I be looking for a formal specification of the Fiasco.OC APIs similar to, say: http://www.cs.cmu.edu/afs/cs/project/mach/public/doc/osf/kernel_interface.ps Thanks for your help! :) Neal

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FOSDEM microkernel devroom video recordings
by Julian Stecklina 18 Oct '13

18 Oct '13

Hello fellow microkernel hackers, the FOSDEM organizers are going to try to provide video recording equipment to all devrooms, but don't have the (wo)manpower to do the actual recording. To have recordings of the talks in the microkernel devroom, we need one volunteer. So if you planned on attending the devroom and are not afraid of a video camera, this is a great opportunity to contribute. Just send me a mail. Of course, every speaker is given a chance to opt out of recording his talk. Thanks, Julian PS. Don't forget to submit your talk until Dec 1st: https://os.inf.tu-dresden.de/pipermail/l4-hackers/2013/006068.html

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Invitation to connect on LinkedIn
by Rahul Singhal 17 Oct '13

17 Oct '13

LinkedIn ------------ I'd like to add you to my professional network on LinkedIn. - Rahul Rahul Singhal Student at Indian Institute of Technology, Bombay Mumbai Area, India Confirm that you know Rahul Singhal: https://www.linkedin.com/e/-24ilnx-hmw5i1gw-4n/isd/17375721641/HSxn-9Vu/?hs… -- You are receiving Invitation to Connect emails. Click to unsubscribe: http://www.linkedin.com/e/-24ilnx-hmw5i1gw-4n/d2b6lZFP4STrtUgHOnSplZ2KmSz6E… (c) 2012 LinkedIn Corporation. 2029 Stierlin Ct, Mountain View, CA 94043, USA.

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Client Server application with l4linux
by Wajidali Whowe 14 Oct '13

14 Oct '13

Dear all, I am interested in implementing a client-server application between an l4linux instance and an application running on top of u-kernel. I reviewed the client and server examples and thought writing a character driver for an l4linux which serves as either a client or a server. Nevertheless clearly the client / server examples are written in C++. Do you have any suggestion? Best Regards.

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L4/Fiasco.OC & gcc-4.7
by Daniel Müller 14 Oct '13

14 Oct '13

Hello, are there any known issues with Fiasco.OC in conjunction with gcc-4.7? I've just upgrade from 4.6.3 to 4.7.3 and I see warnings of the form: KERNEL: Warning: nothing mapped: (Obj_space) from [0xffffffffffd97dd8/36]: 000000000000044c size: 0000000000000001 to [0xffffffffffd97d28/50] without changes to any of the previously working source codes. Going back to 4.6.3 fixes the issue. Thanks, Daniel

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