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Re: Graphical desktop, l4con, mag
by Leslie Zhai 07 Jun '17

07 Jun '17

Hi Jean, Happy holiday :) 在 2017年06月05日 23:43, Jean Wolter 写道: > Hello Leslie, > > today are public holidays in Germany, so I will try to follow up on > the issue tomorrow. I downloaded your binaries and am able to > reproduce the problem. It appears to be a problem with the fiasco > build. When I use my fiasco image build with gcc 4.9 l4/build/.config GCCDIR=/usr/lib/gcc/x86_64-redhat-linux/6.3.1 ... > the systems boots. When I use your fiasco image it triggers the > pagefault shown in your screen shots. > > There are some warnings in the boot sequence with your kernel: > "Warning: Buddy::alloc: Size mismatch: e58 v 1000" ... fiasco/build/globalconfig.out # CONFIG_AMD64_K8 is not set # CONFIG_AMD64_CORE2 is not set CONFIG_AMD64_CORE_I=y l4/build/.config CONFIG_BUILD_ARCH="amd64" CONFIG_BUILD_ARCH_amd64=y CONFIG_CPU="K8" CONFIG_CPU_X86_K8=y does it mean this mismatch? but when I rebuilt fiasco with CONFIG_AMD64_K8=y # CONFIG_AMD64_CORE2 is not set # CONFIG_AMD64_CORE_I is not set the same story so I need to go deeper into fiasco/kern/buddy_alloc.cpp > > > regards, > > Jean > > -- Regards, Leslie Zhai - a LLVM hackerhttps://reviews.llvm.org/p/xiangzhai/

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Re: clang-5.0 is not supported. Please use one of the following versions
by Leslie Zhai 06 Jun '17

06 Jun '17

Dear Rui, ご回答有難うございます！ > I believe the LLD's linker script is now fairly decent that you can expect it should work in most cases. -- Regards, Leslie Zhai https://reviews.llvm.org/p/xiangzhai/

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Re: clang-5.0 is not supported. Please use one of the following versions
by Leslie Zhai 05 Jun '17

05 Jun '17

Hi Adam, Thanks for your reply! > we tend to defer to enable versions until they're actually released. Please remove 5.0 :) And what about LLVM's lld? I found it is only for ld https://svn.l4re.org/repos/oc/l4re/trunk/kernel/fiasco/src/kernel.amd64.ld correct? -- Regards, Leslie Zhai https://reviews.llvm.org/p/xiangzhai/

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Re: Graphical desktop, l4con, mag
by Leslie Zhai 05 Jun '17

05 Jun '17

在 2017年06月03日 04:56, Jean Wolter 写道: > Hello Leslie, > > On 02/06/17 11:33, Jean Wolter wrote: >> I replaced my "ned" binary with yours and the system boots up fine. >> >> Now I wonder how I could reproduce your problem. It looks like I >> >> * either need all binaries or >> * need to build them the same way you are building them. I used a >> fresh checkout from the svn repositories and use gcc version >> 4.9.2 (Debian 4.9.2-10) to build the components. >> > > Since I neither have your binaries nor know how you build them https://drive.google.com/open?id=0ByE8c-y74l_uLUdKWG9NWndnSUk and https://drive.google.com/open?id=0ByE8c-y74l_udUtJOTZvc3BycG8 > I thought about how you could diagnose the problem further. To > demonstrate how to do this I intentionally added a null pointer > dereference to ned and would like to discuss how I would diagnose this. > > --- ned/server/src/main.cc (revision 72) > +++ ned/server/src/main.cc (working copy) > @@ -35,6 +35,8 @@ > Dbg::set_level(Dbg::Warn); > info.printf("Hello from Ned\n"); > > + *(int *)0 = 0; > + > boot_info.printf("cmdline: "); > for (int i = 0; i < argc; ++i) > boot_info.cprintf("%s ", argv[i]); > > 1. Add -serial_esc -wait to kernel options in conf/modules.list > > --- modules.list (revision 72) > +++ modules.list (working copy) > @@ -80,6 +80,7 @@ > module libuc_c.so > > entry framebuffer-example-x86 > +kernel fiasco -serial_esc -wait > roottask moe rom/x86-fb.cfg > module x86-fb.cfg > module l4re > > If you boot this the kernel will enter the kernel debugger before > doing anything else. Enter the following commands: > > * P+ /* show every pagefault before forwarding it to the pager */ > * Prx0<space>100<space> /* restrict pagefault logging to pagefaults > between [0-100] */. > * g /* go */ > > The kernel should stop when the access to 0x18 happens, then you can > enter the kernel debugger using 'i' and can check who is responsible > and maybe get a correct instruction pointer. If I do this here it > looks like follows (I added -serial stdio to the qemu options): > > qemu-system-x86_64 -kernel > /home/jw5/build/tmp/l4re/bin/amd64_K8/bootstrap -append "bootstrap > -modaddr 0x01100000" -serial stdio -initrd > "/home/jw5/build/tmp/fiasco//fiasco -serial_esc > -wait,/home/jw5/build/tmp/l4re/bin/amd64_K8/l4f/sigma0 > ,/home/jw5/build/tmp/l4re/bin/amd64_K8/l4f/moe > rom/x86-fb.cfg,/home/jw5/src/l4resvn/src/l4/conf/examples//x86-fb.cfg > ,/home/jw5/build/tmp/l4re/bin/amd64_K8/l4f/l4re > ,/home/jw5/build/tmp/l4re/bin/amd64_K8/l4f/ned > ,/home/jw5/build/tmp/l4re/bin/amd64_K8/l4f/io > ,/home/jw5/src/l4resvn/src/l4/pkg/io/io/config//x86-legacy.devs > ,/home/jw5/src/l4resvn/src/l4/conf/examples//x86-fb.io > ,/home/jw5/build/tmp/l4re/bin/amd64_K8/l4f/fb-drv > ,/home/jw5/build/tmp/l4re/bin/amd64_K8/l4f/mag > ,/home/jw5/build/tmp/l4re/bin/amd64_K8/l4f/ex_fb_spectrum_cc " > ... > Freeing init code/data: 49152 bytes (12 pages) > > Calibrating timer loop... done. > > --------------------------------------------------------------------- > CPU 0 [fffffffff003df99]: Wait > jdb: P+ > PF logging enabled > jdb: Pr restrict to addr in [0-100] /* pressed > Prx0<space>100<space> */ > PF logging enabled, restricted to 0000000000000000 <= pfa <= > 0000000000000100 > jdb: g /* g does no show up in output */ > ... > MOE: cmdline: /home/jw5/build/tmp/l4re/bin/amd64_K8/l4f/moe rom/x86-fb.cfg > MOE: Starting: rom/ned rom/x86-fb.cfg > MOE: loading 'rom/ned' > pf: 0022 pfa=0000000000000000 ip=00000000010038a2 (w-) > spc=0xffffffff807c3dd8 > /* press i */ > --------------------------------------------------------------------- > CPU 0 [fffffffff0062116]: LOG > jdb: > > Now you can use the kernel debugger to inspect the current state of > the system. Here I simply use addr2line to find the error: > > addr2line -p -i -e bin/amd64_K8/l4f/ned -a 10038a2 > 0x00000000010038a2: > /home/jw5/src/l4resvn/src/l4/pkg/l4re-core/ned/server/src/main.cc:38 > (inlined by) > /home/jw5/src/l4resvn/src/l4/pkg/l4re-core/ned/server/src/main.cc:77 > > > Line 38 is the line with the null pointer dereference. > > I hope this helps, > Jean > > > -- Regards, Leslie Zhai - a LLVM hacker https://reviews.llvm.org/p/xiangzhai/

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Re: Graphical desktop, l4con, mag
by Leslie Zhai 05 Jun '17

05 Jun '17

在 2017年06月03日 04:56, Jean Wolter 写道: > Hello Leslie, > > On 02/06/17 11:33, Jean Wolter wrote: >> I replaced my "ned" binary with yours and the system boots up fine. >> >> Now I wonder how I could reproduce your problem. It looks like I >> >> * either need all binaries or >> * need to build them the same way you are building them. I used a >> fresh checkout from the svn repositories and use gcc version >> 4.9.2 (Debian 4.9.2-10) to build the components. >> > > Since I neither have your binaries nor know how you build them I > thought about how you could diagnose the problem further. To > demonstrate how to do this I intentionally added a null pointer > dereference to ned and would like to discuss how I would diagnose this. > > --- ned/server/src/main.cc (revision 72) > +++ ned/server/src/main.cc (working copy) > @@ -35,6 +35,8 @@ > Dbg::set_level(Dbg::Warn); > info.printf("Hello from Ned\n"); > > + *(int *)0 = 0; > + > boot_info.printf("cmdline: "); > for (int i = 0; i < argc; ++i) > boot_info.cprintf("%s ", argv[i]); > > 1. Add -serial_esc -wait to kernel options in conf/modules.list > > --- modules.list (revision 72) > +++ modules.list (working copy) > @@ -80,6 +80,7 @@ > module libuc_c.so > > entry framebuffer-example-x86 > +kernel fiasco -serial_esc -wait > roottask moe rom/x86-fb.cfg > module x86-fb.cfg > module l4re > > If you boot this the kernel will enter the kernel debugger before > doing anything else. Enter the following commands: > > * P+ /* show every pagefault before forwarding it to the pager */ > * Prx0<space>100<space> /* restrict pagefault logging to pagefaults > between [0-100] */. > * g /* go */ > > The kernel should stop when the access to 0x18 happens, then you can > enter the kernel debugger using 'i' and can check who is responsible > and maybe get a correct instruction pointer. If I do this here it > looks like follows (I added -serial stdio to the qemu options): > > qemu-system-x86_64 -kernel > /home/jw5/build/tmp/l4re/bin/amd64_K8/bootstrap -append "bootstrap > -modaddr 0x01100000" -serial stdio -initrd > "/home/jw5/build/tmp/fiasco//fiasco -serial_esc > -wait,/home/jw5/build/tmp/l4re/bin/amd64_K8/l4f/sigma0 > ,/home/jw5/build/tmp/l4re/bin/amd64_K8/l4f/moe > rom/x86-fb.cfg,/home/jw5/src/l4resvn/src/l4/conf/examples//x86-fb.cfg > ,/home/jw5/build/tmp/l4re/bin/amd64_K8/l4f/l4re > ,/home/jw5/build/tmp/l4re/bin/amd64_K8/l4f/ned > ,/home/jw5/build/tmp/l4re/bin/amd64_K8/l4f/io > ,/home/jw5/src/l4resvn/src/l4/pkg/io/io/config//x86-legacy.devs > ,/home/jw5/src/l4resvn/src/l4/conf/examples//x86-fb.io > ,/home/jw5/build/tmp/l4re/bin/amd64_K8/l4f/fb-drv > ,/home/jw5/build/tmp/l4re/bin/amd64_K8/l4f/mag > ,/home/jw5/build/tmp/l4re/bin/amd64_K8/l4f/ex_fb_spectrum_cc " > ... > Freeing init code/data: 49152 bytes (12 pages) > > Calibrating timer loop... done. > > --------------------------------------------------------------------- > CPU 0 [fffffffff003df99]: Wait > jdb: P+ > PF logging enabled > jdb: Pr restrict to addr in [0-100] /* pressed > Prx0<space>100<space> */ > PF logging enabled, restricted to 0000000000000000 <= pfa <= > 0000000000000100 > jdb: g /* g does no show up in output */ > ... > MOE: cmdline: /home/jw5/build/tmp/l4re/bin/amd64_K8/l4f/moe rom/x86-fb.cfg > MOE: Starting: rom/ned rom/x86-fb.cfg > MOE: loading 'rom/ned' > pf: 0022 pfa=0000000000000000 ip=00000000010038a2 (w-) > spc=0xffffffff807c3dd8 > /* press i */ > --------------------------------------------------------------------- > CPU 0 [fffffffff0062116]: LOG > jdb: > > Now you can use the kernel debugger to inspect the current state of > the system. Here I simply use addr2line to find the error: > > addr2line -p -i -e bin/amd64_K8/l4f/ned -a 10038a2 > 0x00000000010038a2: > /home/jw5/src/l4resvn/src/l4/pkg/l4re-core/ned/server/src/main.cc:38 > (inlined by) > /home/jw5/src/l4resvn/src/l4/pkg/l4re-core/ned/server/src/main.cc:77 > > > Line 38 is the line with the null pointer dereference. Thanks for your help! worked :) addr2line -p -i -e bin/amd64_K8/l4f/ned -a 100398d 0x000000000100398d: /home/zhaixiang/project/l4re/l4/pkg/l4re-core/ned/server/src/main.cc:38 (inlined by) /home/zhaixiang/project/l4re/l4/pkg/l4re-core/ned/server/src/main.cc:77 and I need to carefully read JDB manual. > > I hope this helps, > Jean > > > -- Regards, Leslie Zhai - a LLVM hacker https://reviews.llvm.org/p/xiangzhai/

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Re: Graphical desktop, l4con, mag
by Leslie Zhai 04 Jun '17

04 Jun '17

Hi Jean, Thanks for your help! 在 2017年06月03日 04:56, Jean Wolter 写道: > Hello Leslie, > > On 02/06/17 11:33, Jean Wolter wrote: >> I replaced my "ned" binary with yours and the system boots up fine. >> >> Now I wonder how I could reproduce your problem. It looks like I >> >> * either need all binaries or >> * need to build them the same way you are building them. I used a >> fresh checkout from the svn repositories and use gcc version >> 4.9.2 (Debian 4.9.2-10) to build the components. >> > > Since I neither have your binaries nor know how you build them I follow the http://os.inf.tu-dresden.de/fiasco/build.html and http://l4re.org/build.html and my environment is Fedora 24, gcc 6.3.1, qemu 2.6.2 and clang-5.0svn. hello example is able to work :) > I thought about how you could diagnose the problem further. To > demonstrate how to do this I intentionally added a null pointer > dereference to ned and would like to discuss how I would diagnose this. > > --- ned/server/src/main.cc (revision 72) > +++ ned/server/src/main.cc (working copy) > @@ -35,6 +35,8 @@ > Dbg::set_level(Dbg::Warn); > info.printf("Hello from Ned\n"); > > + *(int *)0 = 0; > + > boot_info.printf("cmdline: "); > for (int i = 0; i < argc; ++i) > boot_info.cprintf("%s ", argv[i]); > > 1. Add -serial_esc -wait to kernel options in conf/modules.list > > --- modules.list (revision 72) > +++ modules.list (working copy) > @@ -80,6 +80,7 @@ > module libuc_c.so > > entry framebuffer-example-x86 > +kernel fiasco -serial_esc -wait > roottask moe rom/x86-fb.cfg > module x86-fb.cfg > module l4re > > If you boot this the kernel will enter the kernel debugger before > doing anything else. Enter the following commands: > > * P+ /* show every pagefault before forwarding it to the pager */ > * Prx0<space>100<space> /* restrict pagefault logging to pagefaults > between [0-100] */. > * g /* go */ > > The kernel should stop when the access to 0x18 happens, then you can > enter the kernel debugger using 'i' and can check who is responsible > and maybe get a correct instruction pointer. If I do this here it > looks like follows (I added -serial stdio to the qemu options): > > qemu-system-x86_64 -kernel > /home/jw5/build/tmp/l4re/bin/amd64_K8/bootstrap -append "bootstrap > -modaddr 0x01100000" -serial stdio -initrd > "/home/jw5/build/tmp/fiasco//fiasco -serial_esc > -wait,/home/jw5/build/tmp/l4re/bin/amd64_K8/l4f/sigma0 > ,/home/jw5/build/tmp/l4re/bin/amd64_K8/l4f/moe > rom/x86-fb.cfg,/home/jw5/src/l4resvn/src/l4/conf/examples//x86-fb.cfg > ,/home/jw5/build/tmp/l4re/bin/amd64_K8/l4f/l4re > ,/home/jw5/build/tmp/l4re/bin/amd64_K8/l4f/ned > ,/home/jw5/build/tmp/l4re/bin/amd64_K8/l4f/io > ,/home/jw5/src/l4resvn/src/l4/pkg/io/io/config//x86-legacy.devs > ,/home/jw5/src/l4resvn/src/l4/conf/examples//x86-fb.io > ,/home/jw5/build/tmp/l4re/bin/amd64_K8/l4f/fb-drv > ,/home/jw5/build/tmp/l4re/bin/amd64_K8/l4f/mag > ,/home/jw5/build/tmp/l4re/bin/amd64_K8/l4f/ex_fb_spectrum_cc " > ... > Freeing init code/data: 49152 bytes (12 pages) > > Calibrating timer loop... done. > > --------------------------------------------------------------------- > CPU 0 [fffffffff003df99]: Wait > jdb: P+ when I input p+ then pressed Enter, but jdb did not print out "PF logging enabled" to me https://pbs.twimg.com/media/DBcu1DUUwAAkiDl.png > PF logging enabled > jdb: Pr restrict to addr in [0-100] /* pressed > Prx0<space>100<space> */ > PF logging enabled, restricted to 0000000000000000 <= pfa <= > 0000000000000100 > jdb: g /* g does no show up in output */ but input g then pressed Enter will continue to go https://pbs.twimg.com/media/DBc0XlWUAAAmgSN.png sorry I am not familiar with jdb, but have some experience with gdb. > ... > MOE: cmdline: /home/jw5/build/tmp/l4re/bin/amd64_K8/l4f/moe rom/x86-fb.cfg > MOE: Starting: rom/ned rom/x86-fb.cfg > MOE: loading 'rom/ned' > pf: 0022 pfa=0000000000000000 ip=00000000010038a2 (w-) > spc=0xffffffff807c3dd8 > /* press i */ > --------------------------------------------------------------------- > CPU 0 [fffffffff0062116]: LOG > jdb: > > Now you can use the kernel debugger to inspect the current state of > the system. Here I simply use addr2line to find the error: so I failed to debug the on purpose null ptr dereference issue *(int *)0 = 0; in your patch via jdb. > addr2line -p -i -e bin/amd64_K8/l4f/ned -a 10038a2 > 0x00000000010038a2: > /home/jw5/src/l4resvn/src/l4/pkg/l4re-core/ned/server/src/main.cc:38 > (inlined by) > /home/jw5/src/l4resvn/src/l4/pkg/l4re-core/ned/server/src/main.cc:77 > > > Line 38 is the line with the null pointer dereference. > > I hope this helps, > Jean > > > -- Regards, Leslie Zhai - a LLVM hacker https://reviews.llvm.org/p/xiangzhai/

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Re: Graphical desktop, l4con, mag
by Leslie Zhai 02 Jun '17

02 Jun '17

在 2017年06月02日 15:34, Jean Wolter 写道: > > Hello Leslie, > > On 02/06/17 05:52, Leslie Zhai wrote: >> Thanks for your reply! but I met the same story for L4Linux >> https://pbs.twimg.com/media/DBSQtoNUIAEE2HY.png > It looks like the very same error, an unhandled read page-fault at > address 0x18 triggered by an instruction at 0x102d72a. > >> > Maybe you could use addr2line/objdump >> > to figure out, what happens at address 0x102d72a in ned. >> >> cd /home/zhaixiang/project/l4re/l4/build >> addr2line -p -e bin/amd64_K8/l4f/ned 0x102d72a >> >> but there is no output easy to read for humans, I am not familiar >> with addr2line, please give me some advice, thanks a lot! > If I try it with an instruction pointer somewhere in the main function > it looks like follows: > > ~/build/tmp/l4re/bin/amd64_K8/l4f$ addr2line -p -i -e ned -a 10038b3 > 0x00000000010038b3: > /home/.../src/l4resvn/src/l4/pkg/l4re-core/ned/server/src/main.cc:39 > (inlined by) > /home/.../src/l4resvn/src/l4/pkg/l4re-core/ned/server/src/main.cc:75 > > >> objdump -D bin/amd64_K8/l4f/ned > ned.S >> > If you use -lSd you should see line number information in the > disassembled output, e.g: > > /home/.../src/l4resvn/src/l4/pkg/l4re-core/ned/server/src/main.cc:39 > for (int i = 0; i < argc; ++i) > 10038b3: 85 db test %ebx,%ebx > > >> 102d72a: 66 0f 12 05 9e 7b 02 movlpd 0x27b9e(%rip),%xmm0 # >> 10552d0 <_ZL7HOOKKEY+0x 8> >> is it enough to figure out what happened? if not, I will upload the >> disassemble to my Google drive. > This looks strange. There is nothing looking like an access to 0x18. > Could send me your ned binary? https://drive.google.com/open?id=0ByE8c-y74l_uVlB6cnJBdWV1VzA > > regards, > Jean > -- Regards, Leslie Zhai - a LLVM hacker https://reviews.llvm.org/p/xiangzhai/

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xorriso : FAILURE : Not a known command
by Leslie Zhai 02 Jun '17

02 Jun '17

Hi L4 hackers, When I Running hello.iso http://os.inf.tu-dresden.de/fiasco/build.html via *make grub2iso E=hello MODULE_SEARCH_PATH=/path/to/fiasco-build-dir *it failed to generate ISO, xorriso thrown such error: xorriso : FAILURE : Not a known command: '-f' xorriso : aborting : -abort_on 'FAILURE' encountered 'FAILURE' Failed to create ISO at tool/lib/L4/Grub.pm line 123. Makefile:598: recipe for target 'grub2iso' failed so I simply changed the option: Index: tool/lib/L4/Grub.pm =================================================================== --- tool/lib/L4/Grub.pm (revision 72) +++ tool/lib/L4/Grub.pm (working copy) @@ -116,7 +116,7 @@ close A; }; my $cmd = "$mkr --output=\"$isofilename\" $dir ". - join(' ', @morefiles)." --$opt -f"; + join(' ', @morefiles)." --$opt -follow default"; system("$cmd"); die "Failed to create ISO" if $?; # grub-mkrescue does not propagate internal tool errors please review my patch, thanks a lot! -- Regards, Leslie Zhai - a LLVM hacker https://reviews.llvm.org/p/xiangzhai/

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Graphical desktop, l4con, mag
by teclis High Elf 02 Jun '17

02 Jun '17

Guten Tag, I've got the Hello app runing with fiasco and l4re in qemu, how do I get the graphical UI and console running that I see on the screen shots page? Do I need to use l4con and mag? I don't see an entry with l4con in modules.list. danke * <http://german.about.com/library/media/Audio/gutentag.wav>*

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L4Linux CONFIG_MTRR must not be enabled
by 翟翔 02 Jun '17

02 Jun '17

Hi L4 hackers, When I am building L4Linux https://l4linux.org/build.shtml make O=build menuconfig changed the L4 tree build directory, then Exit for saving to .config make O=build it thrown ERROR: CONFIG_XXX must not be enabled, then I edited build/.config to comment the CONFIG_XXX is not set, then make O=build again, but it always thrown such error: make[1]: Entering directory '/home/zhaixiang/project/l4linux/build' =============================================== For quick build instructions, please visit: http://wiki.tudos.org/Quickstart http://l4linux.org/build.shtml =============================================== ERROR: CONFIG_MTRR must not be enabled. ERROR: CONFIG_DMI must not be enabled. ERROR: CONFIG_X86_SMAP must not be enabled. arch/l4/Makefile:578: recipe for target 'check_linux_config' failed make[1]: *** [check_linux_config] Error 1 make[1]: Leaving directory '/home/zhaixiang/project/l4linux/build' Makefile:150: recipe for target 'sub-make' failed make: *** [sub-make] Error 2 even I commented CONFIG_MTRR, CONFIG_DMI and CONFIG_X86_SMAP is not set, but rebuilt it again, the CONFIG_MTRR=y, are they requires by other modules? infinite dependence issue? so I simply changed the arch/l4/Makefile Index: arch/l4/Makefile =================================================================== --- arch/l4/Makefile (revision 54) +++ arch/l4/Makefile (working copy) @@ -557,9 +557,9 @@ DIS_OPTS-arm-32 := PERF_EVENTS ARM_PATCH_PHYS_VIRT HIGHMEM \ DEBUG_RODATA DEBUG_ALIGN_RODATA DIS_OPTS := HIGHMEM4G HIGHMEM64G PCI_GOANY PCI_GOBIOS \ - X86_MCE X86_MCE MTRR PARAVIRT KEXEC MCA SOFTWARE_SUSPEND APM \ - CPU_FREQ VM86 X86_DS X86_PTRACE_BTS HT_IRQ DMI \ - TRANSPARENT_HUGEPAGE COMPACTION X86_PAE ACPI X86_SMAP \ + X86_MCE X86_MCE PARAVIRT KEXEC MCA SOFTWARE_SUSPEND APM \ + CPU_FREQ VM86 X86_DS X86_PTRACE_BTS HT_IRQ \ + TRANSPARENT_HUGEPAGE COMPACTION X86_PAE ACPI \ M486 M586 M586TSC M586MMX PNP \ X86_16BIT MICROCODE \ $(DIS_OPTS-$(BASEARCH)-$(BITS)) it is monkey patch, please give me some advice, thanks a lot! -- Regards, Leslie Zhai - a LLVM hacker https://reviews.llvm.org/p/xiangzhai/

3 2

Benchmarks in l4
by Maxim Baryshnikov 01 Jun '17

01 Jun '17

Hello everybody, Does the L4re contain some kind of simple performance benchmarks which are already prepared to use? I've tried to launch some demos from the ferret package but not succeed... Thank you in advance for any suggestions. Sincerely, Maxim Baryshnikov.

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Re: libfs/ FUSE on L4Re
by Leslie Zhai 01 Jun '17

01 Jun '17

diff --git a/libfs/lib/libc_backend/l4fs.cc b/libfs/lib/libc_backend/l4fs.cc index 7a229ff..31ad120 100644 --- a/libfs/lib/libc_backend/l4fs.cc +++ b/libfs/lib/libc_backend/l4fs.cc @@ -219,10 +219,10 @@ int L4fs_dir::get_entry(const char *name, int flags, mode_t mode, //printf("mode=%x,flags=%x\n", mode, flags); if (S_ISDIR(mode)) { //printf("open '%s' as directory\n", name); - *file = new L4fs_dir(_svr, fh); + *file = cxx::ref_ptr(new L4fs_dir(_svr, fh)); } else { //printf("open '%s' as file\n", name); - *file = new L4fs_file(_svr, fh); + *file = cxx::ref_ptr(new L4fs_file(_svr, fh)); } return (*file) ? 0 : -ENOMEM; @@ -325,7 +325,7 @@ int L4fs_file_system::mount(char const *source, unsigned long mountflags, if (fh < 0) return fh; - *dir = new L4fs_dir(svr, fh); + *dir = cxx::ref_ptr(new L4fs_dir(svr, fh)); if (!dir) return -ENOMEM; 在 2017年06月01日 15:36, Xiang Zhai 写道: > Hi Florian, > > > /home/zhaixiang/project/l4re/l4/pkg/libfs/lib/libc_backend/l4fs.cc: In > member function ‘virtual int L4fs::L4fs_dir::get_entry(const char*, > int, mode_t, cxx::Ref_ptr<L4Re::Vfs::File>*)’: > /home/zhaixiang/project/l4re/l4/pkg/libfs/lib/libc_backend/l4fs.cc:222:38: > error: no match for ‘operator=’ (operand types are > ‘cxx::Ref_ptr<L4Re::Vfs::File>’ and ‘L4fs::L4fs_dir*’) > *file = new L4fs_dir(_svr, fh); > ^ > In file included from > /home/zhaixiang/project/l4re/l4/build/include/l4/l4re_vfs/vfs.h:41:0, > from > /home/zhaixiang/project/l4re/l4/build/include/l4/l4re_vfs/backend:22, > from > /home/zhaixiang/project/l4re/l4/pkg/libfs/lib/libc_backend/l4fs.cc:15: > /home/zhaixiang/project/l4re/l4/build/include/l4/cxx/ref_ptr:186:8: > note: candidate: template<class OT> void cxx::Ref_ptr<T, > CNT>::operator=(const cxx::Ref_ptr<OT>&) [with OT = OT; T = > L4Re::Vfs::File; CNT = cxx::Default_ref_counter] > void operator = (Ref_ptr<OT> const &o) throw() > ^~~~~~~~ > /home/zhaixiang/project/l4re/l4/build/include/l4/cxx/ref_ptr:186:8: > note: template argument deduction/substitution failed: > /home/zhaixiang/project/l4re/l4/pkg/libfs/lib/libc_backend/l4fs.cc:222:38: > note: mismatched types ‘const cxx::Ref_ptr<T>’ and ‘L4fs::L4fs_dir*’ > *file = new L4fs_dir(_svr, fh); > ^ > In file included from > /home/zhaixiang/project/l4re/l4/build/include/l4/l4re_vfs/vfs.h:41:0, > from > /home/zhaixiang/project/l4re/l4/build/include/l4/l4re_vfs/backend:22, > from > /home/zhaixiang/project/l4re/l4/pkg/libfs/lib/libc_backend/l4fs.cc:15: > /home/zhaixiang/project/l4re/l4/build/include/l4/cxx/ref_ptr:193:8: > note: candidate: void cxx::Ref_ptr<T, CNT>::operator=(const > cxx::Ref_ptr<T>&) [with T = L4Re::Vfs::File; CNT = > cxx::Default_ref_counter] > void operator = (Ref_ptr<T> const &o) throw() > ^~~~~~~~ > /home/zhaixiang/project/l4re/l4/build/include/l4/cxx/ref_ptr:193:8: > note: no known conversion for argument 1 from ‘L4fs::L4fs_dir*’ to > ‘const cxx::Ref_ptr<L4Re::Vfs::File>&’ > /home/zhaixiang/project/l4re/l4/build/include/l4/cxx/ref_ptr:203:8: > note: candidate: void cxx::Ref_ptr<T, CNT>::operator=(cxx::Ref_ptr<T, > CNT>::Null_type) [with T = L4Re::Vfs::File; CNT = > cxx::Default_ref_counter; cxx::Ref_ptr<T, CNT>::Null_type = > std::nullptr_t] > void operator = (Null_type) throw() > ^~~~~~~~ > /home/zhaixiang/project/l4re/l4/build/include/l4/cxx/ref_ptr:203:8: > note: no known conversion for argument 1 from ‘L4fs::L4fs_dir*’ to > ‘cxx::Ref_ptr<L4Re::Vfs::File>::Null_type {aka std::nullptr_t}’ > /home/zhaixiang/project/l4re/l4/build/include/l4/cxx/ref_ptr:218:8: > note: candidate: template<class OT> void cxx::Ref_ptr<T, > CNT>::operator=(cxx::Ref_ptr<OT>&&) [with OT = OT; T = > L4Re::Vfs::File; CNT = cxx::Default_ref_counter] > void operator = (Ref_ptr<OT> &&o) throw() > ^~~~~~~~ > /home/zhaixiang/project/l4re/l4/build/include/l4/cxx/ref_ptr:218:8: > note: template argument deduction/substitution failed: > /home/zhaixiang/project/l4re/l4/pkg/libfs/lib/libc_backend/l4fs.cc:222:38: > note: mismatched types ‘cxx::Ref_ptr<T>’ and ‘L4fs::L4fs_dir*’ > *file = new L4fs_dir(_svr, fh); > ^ > In file included from > /home/zhaixiang/project/l4re/l4/build/include/l4/l4re_vfs/vfs.h:41:0, > from > /home/zhaixiang/project/l4re/l4/build/include/l4/l4re_vfs/backend:22, > from > /home/zhaixiang/project/l4re/l4/pkg/libfs/lib/libc_backend/l4fs.cc:15: > /home/zhaixiang/project/l4re/l4/build/include/l4/cxx/ref_ptr:224:8: > note: candidate: void cxx::Ref_ptr<T, > CNT>::operator=(cxx::Ref_ptr<T>&&) [with T = L4Re::Vfs::File; CNT = > cxx::Default_ref_counter] > void operator = (Ref_ptr<T> &&o) throw() > ^~~~~~~~ > /home/zhaixiang/project/l4re/l4/build/include/l4/cxx/ref_ptr:224:8: > note: no known conversion for argument 1 from ‘L4fs::L4fs_dir*’ to > ‘cxx::Ref_ptr<L4Re::Vfs::File>&&’ > > > So I simply added cxx::ref_ptr() for reference counting pointer with > automatic cleanup: > > > diff --git a/libfs/lib/libc_backend/l4fs.cc > b/libfs/lib/libc_backend/l4fs.cc > index 7a229ff..31ad120 100644 > --- a/libfs/lib/libc_backend/l4fs.cc > +++ b/libfs/lib/libc_backend/l4fs.cc > @@ -219,10 +219,10 @@ int L4fs_dir::get_entry(const char *name, int > flags, mode_t mode, > //printf("mode=%x,flags=%x\n", mode, flags); > if (S_ISDIR(mode)) { > //printf("open '%s' as directory\n", name); > - *file = new L4fs_dir(_svr, fh); > + *file = cxx::ref_ptr(new L4fs_dir(_svr, fh)); > } else { > //printf("open '%s' as file\n", name); > - *file = new L4fs_file(_svr, fh); > + *file = cxx::ref_ptr(new L4fs_file(_svr, fh)); > } > > return (*file) ? 0 : -ENOMEM; > @@ -325,7 +325,7 @@ int L4fs_file_system::mount(char const *source, > unsigned long mountflags, > if (fh < 0) > return fh; > > - *dir = new L4fs_dir(svr, fh); > + *dir = cxx::ref_ptr(new L4fs_dir(svr, fh)); > if (!dir) > return -ENOMEM; > > > please review my patch, thanks a lot! > -- Regards, Leslie Zhai - a LLVM hacker https://reviews.llvm.org/p/xiangzhai/

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libfs/ FUSE on L4Re
by Stark, Josef 31 May '17

31 May '17

Hello, yesterday I came across a very interesting paper titled "Porting FUSE to L4Re", accessible here: http://os.inf.tu-dresden.de/papers_ps/pester-beleg.pdf For porting FUSE, the author uses a library called "libfs" which provides filesystem request forwarding and processing, if I understood correctly. It reads as if libfs is already included in L4Re. However, I couldn't find neither FUSE nor libfs in the current L4Re snapshot. Are they by any chance publicly available somewhere else, or are both not to be published? Cheers, Josef

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Microkernel + Alumni Meetup
by Bjoern Doebel 30 May '17

30 May '17

Hi all, it has been a while since we last met for a beer. Water went down the Elbe river, companies were closed, companies were started, research papers got accepted, technical advancements were made. Let's catch up on all of that! To find a suitable time, please visit https://dudle.inf.tu-dresden.de/ukm-01-2017/ Bjoern

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clang-5.0 is not supported. Please use one of the following versions
by Leslie Zhai 29 May '17

29 May '17

Hi L4 hackers, I am using clang (svn trunk 303321) to build fiasco, it thrown such error: kernel/fiasco/src/Makeconf:264: *** clang-5.0 is not supported. Please use one of the following versions: 3.5 3.6 3.7 3.8 so I simply add other versions for clang, please review my patch, thanks a lot! Index: kernel/fiasco/src/Makeconf =================================================================== --- kernel/fiasco/src/Makeconf (revision 72) +++ kernel/fiasco/src/Makeconf (working copy) @@ -245,7 +245,7 @@ CC_WHITELIST-gcc := 4.5 4.6 4.7 4.8 4.9 5 6 -CC_WHITELIST-clang := 3.5 3.6 3.7 3.8 +CC_WHITELIST-clang := 3.5 3.6 3.7 3.8 3.9 4.0 5.0 CC_WHITELIST := $(CC_WHITELIST-$(CC_TYPE)) CC_BLACKLIST-arm-gcc := 4.8.0 4.8.1 4.8.2 -- Regards, Leslie Zhai https://reviews.llvm.org/p/xiangzhai/

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Share exist memory over IPC with L4Re
by Alexander Fratzer 16 May '17

16 May '17

Dear L4-Hackers, I have a very simple problem but I can't find the solution in the L4Re-Doc and examples so far. I wrote a very simple Unix-Like Shell with a Filesystem-Server and a Loader-Server and I implemented some Posix-Call as an abstraction for the communication with the Filesystem-Server (virtual). Now I have a problem of double copies for a read-Operation. I want a complete abstraction from the L4Re mechanisms and the underlying Client-Server architecture for the usage of this interface. The (bad) mechanism is as follow: Function (client side): ssize_t read(int fd, void *buf, size_t count) Algorithm: 1. Allocate Dataspace with size of count. 2. Send Cap of Dataspace to the Filesystem-Server. 3. Copy content of Dataspace to buf. 4. Cleanups. Function (server side): long VFSSrv::op_file_read(VFS::Rights, TaskRegistry::TaskId task, TaskRegistry::FileDescriptor fd, size_t size, L4::Ipc::Snd_fpage& flexp, size_t& rsize) Algorithm: 1. Get Dataspace-Cap from Ipc-fpage. 2. Reserve area with Region-Manager. 3. Attach Dataspace to the area. 4. Copy content of the file to the attached area. 5. Cleanups. This was my first working solution without focus on runtime but the creation of a new task from an ELF-File of 1.4 MB size takes 20 seconds on Cortex A8. This suxx so I have to optimize. Therefor I need a way to share the content of my file (virtual, heap allocated memory) without copying to the client but i don't find a way to share exist memory over IPC. I think I'm using the Dataspace-mechanism in a wrong way but maybe a Dataspace isn't the right choice in my case. A simple solution would be a new Filesystem which is based on Dataspaces but I don't want to do this. Have anybody a better idea? Thanks for help. Best regards Alex.

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Fiasco.OC: null-pointer dereference?
by Stefan Kalkowski 09 May '17

09 May '17

Dear L4-Hackers, recently, I started to upgrade the Fiasco.OC kernel version that is used by the Genode OS framework to the lastly released version (r72). I took the opportunity to upgrade, because the upcoming Genode release uses a fresh compiler toolchain that refused to build the very old Fiasco.OC kernel version that was used until now (r56). Everything went quite smoothly, and I'm glad to see how the kernel develops further. Thanks to all developers at this point! Unfortunately, I stumbled across an issue when it comes to thread destruction. In our system all threads are constructed and destructed by the roottask that is called 'core'. In some cases, not always but quite often, the Ram_quota pointer of the thread object is zero during the call of the Thread_oject's delete operator, which leads to a page-fault within the kernel-code. A simple check[1] before dereferencing the pointer solves the problem, but I wonder whether we will leak quota or memory then, or in general cover some more serious problem. Obviously, we have different usage patterns of syscalls, e.g.: the order of destructing IPC-gates, threads, IRQs, and tasks. Moreover, we still have some very few patches[2] so that the kernel meets our requirements. But none of them explains the thread's Ram_quota pointer getting zero. The page-fault triggers across all x86 and arm platforms that we use. Any hint would be very much appreciated, all the best! Stefan [1] https://github.com/skalk/foc/commit/2b01c9d16fd8e29e6af18fe750be2c8a312b4762 [2] https://github.com/skalk/foc/commits/r72 -- Stefan Kalkowski Genode Labs https://github.com/skalk · http://genode.org/

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Trying to build L4 on NixOS
by Mateusz Czaplinski 09 Apr '17

09 Apr '17

I'm trying to build L4 on NixOS in a VM (long term goal: try to learn how to replace NixOS's kernel with L4Linux, then maybe Genode). I'm getting an error like below: undefined reference to `__stack_chk_fail' during linking of bootstrap.elf - in a GCC's error-barf just after: [bootstrap] ==> Linking bootstrap.elf I've put up the precise Nix expression/script I'm using to build it on github - at: https://github.com/akavel/l4.nix/blob/0108dfcf8d84780e1ba884c41ece0d2dbf4dd… but what it generally boils down to is a sequence of commands like this: $ wget http://os.inf.tu-dresden.de/download/snapshots/l4re-core-2016082114.tar.xz $ tar xf l4re-core-2016082114.tar.xz $ cd l4re-core-2016082114 $ mkdir out $ cp src/l4/mk/defconfig/config.amd64 out/l4/.kconfig $ make -C src/l4 O=out/l4 olddefconfig $ make -C out/l4 I've tried various additional changes, based on some snippets found here and there on teh Internets, like: - adding V=0 to the last make (no idea what it does yet, just some cargo culting) - adding NIX_CFLAGS_COMPILE = "-fno-stack-protector"; to the Nix expression/script (also not really sure where it applies in the stack); but none of the above helped. Any idea what I could try doing to push it further? Thanks, /Mateusz.

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Questions about Fiasco.OC scheduler and L4Linux
by Marc CHALAND 02 Apr '17

02 Apr '17

Hi, I'm doing a study to port old software on top of Fiasco.OC. This soft uses routines which blocks thread scheduling between EnterRegion and LeaveRegion call. Is there any equivalent on TUDOS ? Did somebody already get this challenge ? I would like to know if L4Linux uses Fiasco.OC scheduler or a user land one ? For our i.MX7d board, Freescale provides Linux drivers on 4.1. I don't know yet how many drivers we will need. Do you think it is better to port drivers from 4.1 to L4Linux 4.3 or later or get a L4Linux 4.1. I have no idea about the complexity on doing this. Regards Marc

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L4linux __raw_writesl/readl undefined
by Manolis Ragkousis 01 Apr '17

01 Apr '17

Hello everyone, I am trying to enable sd card support on my zedboard running l4linux and I get this error: ERROR: "__raw_writesl" [drivers/mmc/host/mmci.ko] undefined! ERROR: "__raw_readsl" [drivers/mmc/host/mmci.ko] undefined! make[2]: *** [../scripts/Makefile.modpost:91: __modpost] Error 1 make[1]: *** [/home/manolis/repos/l4linux/Makefile:1173: modules] Error 2 make[1]: *** Waiting for unfinished jobs.... LD ldrImage GZIP vmlinuz LOCINST vmlinuz make[1]: Leaving directory '/home/manolis/repos/l4linux/build' make: *** [Makefile:150: sub-make] Error 2 In order to enable sd card support I understand that I need to enable MMC/SD/SDIO card support in the kernel + ARM AMBA Multimedia Card Interface support. I have followed the instructions from previous emails in this list [1][2]. What am I missing? Is there a config option which enables raw writes/reads on top of L4? Thank you for you time and help, Manolis [1] https://os.inf.tu-dresden.de/pipermail/l4-hackers/2014/006296.html [2] https://os.inf.tu-dresden.de/pipermail/l4-hackers/2014/006417.html

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Can't find device node in /dev/ directory!
by li94575 21 Mar '17

21 Mar '17

Hi, I added some drivers in l4linux, of course, I assigned the corresponding peripheral resources (iomem, irq) to these drivers. From the driver's output log, it seems that they all work well, but when entering the command line, I could not find any relevant device node in /dev/ directory. To my confusion, I can see these devices info in /sys/ directory. The command line args is showing below: mem=64M console=ttyLv0 l4x_rd=rom/ramdisk-" .. L4.Info.arch() .. ".rd ramdisk_size=4000 Any idea?

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Re: Extending l4sys by reading/writing register values of a preempted thread
by Christian Ludwig 21 Mar '17

21 Mar '17

Hi, > I want to implement a new syscall for getting/setting stored register > values of a specific thread (identified by its cap). Why not use ex_regs() on the thread to trigger an exception. That way, the attached userland exception handler can introspect the thread's complete register set. It can also alter the registers, so that the thread continues to run with the modified register set. Is there anything more you need? > Before implementing the syscall, I need to better understand the > kernel-part of Fiasco.OC. Can you help me answer the following questions > and point me to the source code regarding each question: > > * Where (in the source code) are threads preempted and their register > state stored? A thread's userland registers are stored on every entry to the kernel. The class in Fiasco is called Entry_frame. The userland exception handler mentioned above modifies that Entry_frame. > * Where is the register state of a thread loaded to the CPU and the > thread started (e.g. after a preempt)? When the scheduler selects a thread, its userland state (Entry_frame) is restored on exit from kernel mode. > * How can I introspect the stored thread register of a thread in the > kernel debugger JDB? > ** My thoughts: Is it K<kobj_ptr> with kobj_ptr of the thread and the 3 > lines beginning with PC=...? > e.g. > " > PC=010579cc USP=200ffdb0 smlatbeq r9, r0, r2, r5 > [0] 00000003 000010c0 00218003 00000000 tsteq000r5, ip, rrx > [8] 200ffdb0 200ffe40 01086ef0 200ffe98 [c] 200ffef8 010579cc fffffff8 > 20000010 > " Yes, that PC line is the userland program counter. the USP is the userland stack pointer. All userland registers are located at the top of kernel stack for a particular thread. > I also have another, short, off-topic question: > * How can I introspect the capability space of a task inside the kernel > debugger? In short mode, press 's' for a list of all tasks. Select the task in question and the press 'o' to see the capability space for that task. Hope that helps, - Christian

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Extending l4sys by reading/writing register values of a preempted thread
by Denis Huber 13 Mar '17

13 Mar '17

Dear L4 hackers community, I want to implement a new syscall for getting/setting stored register values of a specific thread (identified by its cap). Preliminary note: I'm using the ARM architecture. Before implementing the syscall, I need to better understand the kernel-part of Fiasco.OC. Can you help me answer the following questions and point me to the source code regarding each question: * Where (in the source code) are threads preempted and their register state stored? * Where is the register state of a thread loaded to the CPU and the thread started (e.g. after a preempt)? * Where is the register state stored of each thread? * How can I introspect the stored thread register of a thread in the kernel debugger JDB? ** My thoughts: Is it K<kobj_ptr> with kobj_ptr of the thread and the 3 lines beginning with PC=...? e.g. " PC=010579cc USP=200ffdb0 smlatbeq r9, r0, r2, r5 [0] 00000003 000010c0 00218003 00000000 tsteq000r5, ip, rrx [8] 200ffdb0 200ffe40 01086ef0 200ffe98 [c] 200ffef8 010579cc fffffff8 20000010 " I also have another, short, off-topic question: * How can I introspect the capability space of a task inside the kernel debugger? Kind regards, Denis

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Run L4Re/Fiasco hello example under QEMU (ARM)
by Piotr Piwko 05 Mar '17

05 Mar '17

Hi, I would like to run hello example under qemu-system-arm, so I successfully built the images using gcc-linaro-6.3.1 toolchain with following configuration: L4Re: Target Architecture (ARM architecture) CPU variant (ARMv7A type CPU) Platform Selection (ARM Integrator) Fiasco: Architecture (ARM processor family) Platform (ARM Integrator Platform) CPU (ARM 926 Processor) Unfortunately, after booting boostrap_hello.elf image under qemu-system-arm (the latest 2.8.0 version) there is nothing printed out on the console: $ QEMU_OPTIONS="-machine integratorcp -m 256 -serial mon:stdio -nographic" make qemu E=hello MODULE_SEARCH_PATH=/path/to/fiasco/build/ Do you have any idea what I omitted or what is wrong in my setup? Thank you in advance for your help. -- Piotr Piwko http://www.embedded-engineering.pl/

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read/write to virtual address
by Daniel Krefft 17 Feb '17

17 Feb '17

Hello, while working on a checkpoint/restore mechanism for fiasco.oc, we want to trace read and write (kernel) calls to (virtual) memory. 1) Where are these calls defined? We're just able to find ARM specific calls inside the kernel, which allow writing and reading to/from a virtual address 2) Are these calls (if existent) platform agnostic (user-space)? Is there any kind of interface? Best regards -- Daniel Krefft MSc. Wissenschaftlicher Mitarbeiter Technische Universitaet Muenchen Fakultaet fuer Informatik Lehrstuhl fuer Betriebssysteme Arcisstrasse 21 80333 Muenchen Tel. +49 89 289 18791 daniel.krefft(a)tum.de www.os.in.tum.de/personen/krefft

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