June 2021 - Devel - lists.sel4.systems

hello_rumprun app not worked
by MOHAMAD REZA SHAFIEI 19 Apr '25

19 Apr '25

hi. i'm recently worked on sel4 with camkes framework. when i compile rumprun_hello on x86_64 platform its compiled and build correctly but when run with qemu by ./simulate script, program crashed with this errors: simple_get_extended_bootinfo_length@simple.h:600 simple_get_extended_bootinfo_length not implemented FAULT HANDLER: data fault from hello.hello_0_control (ID 0x1) on address 0x8, pc = 0x402b7f, fsr = 0x6 FAULT HANDLER: Register dump: FAULT HANDLER: rip :0x402b7f , . . so i found that this method not implemented yet so i return 0 in this method and resolved. for second problem that cause failure if trace program and i found that in "init rumprun" process the program failed in the /projects/sel4runtime/include/sel4_arch/x86_64/sel4runtime/thread_arch.h file and sel4runtime_set_tls_base method. so i read git log and in recently commit your team use sel4runtime for thread TLS, so when we run rumprun_hello, the program failed in sel4runtime_set_tls_base method. can you help me fix this bug? thanks for your attention. -- This email was Anti Virus checked by Security Gateway.

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seL4 test on x86
by Yevgeny Lavrov 30 Jan '25

30 Jan '25

Hello, I'm new to seL4 and I'm just doing it for learning purpose. I'm trying to run seL4 test suite or simple hello world task from seL4 tutorials on the real hardware. So far I had no problems compiling seL4 test suite and running via QEMU for both x32 and x64 platforms. However, when I try to run it on the actual hardware following Running on real hardware tutorial for x86 I end up with no output at all and no error msgs that can give me a clue on where something went wrong. After compiling seL4test for x86, I ended up with two images in sel4_dir/images/ folder. Copied them over to /boot/sel4/ folder and created a new GRUB2 entry that looks like this menuentry “seL4 test suite” --class os { load video insmod gzio insmod part_msdos insmod ext2 set root=’(hd0,msdos5)’ multiboot /boot/sel4/kernel-ia32-pc99 module /boot/sel4/sel4test-driver-image-ia32-pc99 } update grub, restart and select the new entry from GRUB menu. I end up with blinking cursor on the top-left side of the screen. Please advise.

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Stuck during invalidate local TLB in Tx2
by Muneeswaran Rajendran 16 Oct '24

16 Oct '24

Hi seL4 Dev team, Can someone explain the reason (share the reference) to invalidate the local TLB during kernel vspace activation as part CPU initialisation. The Tx2 board stuck while performing this operation. As per my understanding both Tx1 and Tx2 are using same A57 core. so the TLB initialisation and invalidation remain same for Tx2 and should not stuck during invalidation.Please correct me if anything wrong here. I understand from that instruction (tlbi vmalle1) which is invalidating stage 1 entries associated to the current VMID. Also from arm mmu code the seL4 setting up (TCR_EL1) TCR register addressing space as 48bit, ASID as 16bit and page table setup 4k granular size. I am using MRS macro to dump the spsr_el1 and dspsr_el0 register to see the state of processor but its throwing synchronous exception. Do we have any other option to dump all the register content to see the state of processor like we have one in 'sel4debug_dump_registers' which is used in sel4test code. Regards, Muneeswaran R

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Questions about Memory Management in seL4
by Daniel Wang 19 May '23

19 May '23

Hi all, Sorry to bother, I have some basic questions about seL4 memory management. Can someone help me? 1. where is the kernel’s address space? I know there are basically three methods: a) separate virtual address space, e.g. through changing page tables on entry into privileged mode to access b) physical space, e.g. through disable automatic hardware translation of virtual addresses on entry into privilege mode c) privilege region in each process’s virtual address space, e.g. through page table to map kernel address into use-mode process. My question is which of this is being used by seL4 microkernel? 2. Objects like CSpace, VSpace, CNode, TCB, Endpoint, etc. are called kernel objects, but it seems all dynamically allocated in thread running/creating time. Are those objects (e.g. Figure 3.3 in seL4 manual) in kernel space or in user space? 3. I read that after the kernel boot up, it passes all resources, untyped memory to the first thread. Are those untyped memory physical memory or virtual memory in a single page? The reason I ask is I’m learning the code of the UNSW AOS project (two of the assignment projects are implementing frame and papers). I’m confused that before the implementation of frames and pages what kind of memory is passed to the the first thread? I saw int AOS project, it uses ut_table_init(), ut_steal_mem(), I wonder what kind of memory it operates on? Thanks -Dan

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ethernet pass-through using CAmkES VM on x86
by meshkat os 29 Sep '21

29 Sep '21

hi I am new to camkes VM on x86. I want to connect the guest to the host via the ethernet network. and I used this ( https://docs.sel4.systems/projects/camkes-vm/) tutorial to create pass-through in minimal example x86. run in qemu on ubuntu 17.10. but the guest os doesn't create an ethernet interface. I also tested zmq example this is qemu options: qemu-system-x86_64 -machine q35,accel=kvm,kernel-irqchip=split -cpu Nehalem,+vme,+pdpe1gb,-xsave,-xsaveopt,-xsavec,-fsgsbase,-invpcid,enforce,+vmx -nographic -serial mon:stdio -m size=2G -enable-kvm -net nic,model=e1000 -net tap,script=no,ifname=tap0 -kernel images/kernel-ia32-pc99 -initrd images/capdl-loader-image-ia32-pc99 and minimal.camkes configs: configuration { VM_CONFIGURATION_DEF() VM_PER_VM_CONFIG_DEF(0) vm0.simple_untyped23_pool = 20; vm0.heap_size = 0x2000000; vm0.guest_ram_mb = 128; vm0.kernel_cmdline = VM_GUEST_CMDLINE; vm0.kernel_image = "bzimage"; vm0.kernel_relocs = "bzimage"; vm0.initrd_image = "rootfs.cpio"; vm0.iospace_domain = 0x0f; vm0_config.pci_devices_iospace = 1; vm0_config.ioports = [ {"start":0x4080, "end":0x4090, "pci_device":0x1f, "name":"SATA"}, {"start":0x4090, "end":0x40a0, "pci_device":0x1f, "name":"SATA"}, {"start":0x40b0, "end":0x40b8, "pci_device":0x1f, "name":"SATA"}, {"start":0x40b8, "end":0x40c0, "pci_device":0x1f, "name":"SATA"}, {"start":0x40c8, "end":0x40cc, "pci_device":0x1f, "name":"SATA"}, {"start":0x40cc, "end":0x40d0, "pci_device":0x1f, "name":"SATA"}, {"start":0x3000, "end":0x3020, "pci_device":0, "name":"Ethernet5"}, ]; vm0_config.pci_devices = [ { "name":"SATA", "bus":0, "dev":0x1f, "fun":2, "irq":"SATA", "memory":[], }, { "name":"Ethernet5", "bus":5, "dev":0, "fun":0, "irq":"Ethernet5", "memory":[ {"paddr":0xc0500000, "size":0x20000, "page_bits":12}, {"paddr":0xc0520000, "size":0x4000, "page_bits":12}, ], }, ]; vm0_config.irqs = [ {"name":"SATA", "source":19, "level_trig":1, "active_low":1, "dest":11}, {"name":"Ethernet5", "source":0x11, "level_trig":1, "active_low":1, "dest":10}, ]; } thanks

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gic v2 vs gic v3
by Chris Koziarz 09 Jul '21

09 Jul '21

Hi all, I'm trying to port camkes-arm-vm to a different platform, that supports gic-v3 In the process, I hit a compilation error: Building C object kernel/CMakeFiles/kernel_all_pp_...rapper_temp_lib.dir/ kernel_all_pp_prune_wrapper_temp.c.obj FAILED: kernel/kernel_all_pp_prune_wrapper_temp.c In file included from /home/chris/camkes-tqma8xqp- vm/kernel/src/arch/arm/object/vcpu.c:15: /home/chris/camkes-tqma8xqp-vm/kernel/include/arch/arm/arch/machine/gic_v2.h:23: error: "IRQ_MASK" redefined [-Werror] 23 #define IRQ_MASK MASK(10u) In file included from kernel/gen_headers/plat/platform_gen.h:23, from /home/chris/camkes-tqma8xqp-vm/kernel/include/plat/ default/plat/machine.h:8, from /home/chris/camkes-tqma8xqp- vm/kernel/include/machine.h:9, from /home/chris/camkes-tqma8xqp- vm/kernel/include/api/syscall.h:10, from /home/chris/camkes-tqma8xqp- vm/kernel/src/api/faults.c:10: /home/chris/camkes-tqma8xqp-vm/kernel/include/arch/arm/arch/machine/gic_v3.h:30: note: this is the location of the previous definition 30 #define IRQ_MASK MASK(16u) which is an indicative that both gic_v3.h & gic_v2.h headers have been included, which is an error because said headers are not compatible: kernel/include/arch/arm/arch/machine/gic_v3.h:#define IRQ_MASK MASK(16u) kernel/include/arch/arm/arch/machine/gic_v2.h:#define IRQ_MASK MASK(10u) So my question is: how can I configure the build to avoid such a conflict? I can grepp the relevant configuration option in CMakeCache.txt: build_tqma8/CMakeCache.txt:CONFIGURE_INTERRUPT_CONTROLLER:INTERNAL=arch/machine/gic_v3.h but cannot see it in ccmake gui because it's "INTERNAL" What is the solution? - replace this option somehow to use gic_v2 and have my HW use gic v.2, or - change compilation options to use gic_v3 everywhere Thanks for any help, Chris.

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Re: Tutorial Problem
by Kent Mcleod 08 Jul '21

08 Jul '21

On Wed, Jun 30, 2021 at 11:53 AM Michael Neises <neisesmichael(a)gmail.com> wrote: > > Kent, > > > > I tried using those extra arguments and got the same error regarding kvm I reported a few minutes ago: > > > > ./simulate: qemu-system-x86_64 -machine q35,accel=kvm,kernel-irqchip=split -cpu Nehalem,+vme,+pdpe1gb,-xsave,-xsaveopt,-xsavec,-fsgsbase,-invpcid,+syscall,+lm,enforce,+vmx -nographic -serial mon:stdio -m size=2G -enable-kvm -device intel-iommu,intremap=off -net nic,model=e1000 -net tap,script=no,ifname=tap0 -kernel images/kernel-x86_64-pc99 -initrd images/capdl-loader-image-x86_64-pc99 Could not access KVM kernel module: No such file or directory > > qemu-system-x86_64: failed to initialize KVM: No such file or directory > There are instructions on how to setup KVM and nested virtualization on the tutorial that I've pasted here: "Note if you are using QEMU it is important to ensure that your host machine has VT-x support and KVM (https://www.linux-kvm.org/page/Main_Page) installed. You also need to ensure you have enabled nested virtulisation with KVM guests as described here (https://www.linux-kvm.org/page/Nested_Guests)" A quick way to check if nested virtualization is enabled (and therefore supported) on your host is to run `cat /sys/module/kvm_intel/parameters/nested`. `Y` should be returned if it's enabled. It may be easier to run the image on an actual machine instead of in qemu. The images produced can be loaded by a multiboot loader such as grub or pxelinux. (https://docs.sel4.systems/Hardware/VMware/#add-grub2-option-to-run-sel4) has an example grub config.

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seL4 Linux guest mmap() crashes the VM
by Hugo V.C. 02 Jul '21

02 Jul '21

Hi, my seL4 Linux VM box just crashed when trying to access a memory address. Basically I simply wanted to use "devmem" tool to just print the content of a specific address in memory and looked like seL4 was unable to handle the guest OS mmap() correctly. Below the console log: # ls /proc/283/maps /proc/283/maps # cat /proc/283/maps 00400000-00532000 r-xp 00000000 00:02 6023 /bin/lighttpd 00541000-00543000 r--p 00131000 00:02 6023 /bin/lighttpd 00543000-00546000 rw-p 00133000 00:02 6023 /bin/lighttpd 00546000-0054d000 rw-p 00000000 00:00 0 0bd0b000-0bd2d000 rw-p 00000000 00:00 0 [heap] 0bd2d000-0bd91000 rw-p 00000000 00:00 0 [heap] ffff82084000-ffff82085000 r--p 00000000 00:00 0 [vvar] ffff82085000-ffff82086000 r-xp 00000000 00:00 0 [vdso] ffffe6c58000-ffffe6c79000 rw-p 00000000 00:00 0 [stack] # devmem 0xffffe6c58000 8 _utspace_split_alloc@split.c:266 Failed to find any untyped capable of creating an object at address 0xffffe6c58000 map_page@mapping.c:68 Failed to map page at address 0xffffe6c58000 with cap 396187, error: 1 sel4utils_map_page_pd@vspace.c:153 Error mapping pages, bailing: 1 map_vm_memory_reservation@guest_memory.c:477 Failed to map address 0xe6c58000 into guest vm vspace vm_map_reservation@guest_memory.c:510 Failed to map vm reservation: Error when mapping into VM's vspace -------- Pagefault from [Linux]: read fault @ PC: 0x414c38 IPA: 0xffffe6c58000, FSR: 0x93020004 Context: x0: 0xffff9cfe6000 x1: 0x0 x2: 0x0 x3: 0x1 x4: 0x3 x5: 0xffffe6c58000 x6: 0x5 x7: 0x20 x8: 0xde x9: 0xffffe539cf54 x10: 0xffff9cfe8050 x11: 0x1 x12: 0x436 pc: 0x414c38 x14: 0xffffffff sp: 0xffffe539bb70 spsr: 0x60000000 x13: 0x1 x15: 0x3 x16: 0xffff9cf486c8 x17: 0x4c3870 x18: 0x0 x19: 0x8 x20: 0x0 x21: 0x4c3000 x22: 0xffffe539bd98 x23: 0xffffe6c58000 x24: 0x0 x25: 0x0 x26: 0x0 x27: 0x0 x28: 0x0 x29: 0xffffe539bc60 x30: 0x414bac m-------- main_continued@main.c:1134 Failed to run VM Halting... My three concerns here are: 1) Why this guest mmap() is crashing the VM? Memory address is valid (just guest user space process stack). 2) Is it possible to have some kind of "dump and reboot VM" when a VM and/or guest OS crashes? 3) Are there any plans to formally verify the seL4's VM camkes code? Thank you!

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Camkes SerialServer and util_libs/libplatsupport with ODROID-C4
by Robert Reid 01 Jul '21

01 Jul '21

Hi everyone Summary - trying to get util_libs/libplatsupport going for a HardKernel ODROID-C4, using the camkes serialserver_polling app - but not having any luck with mapping the UART. I'd welcome any explanations of what you think is happening here. The background and my progress follows. I thought I'd dive into the seL4 world and do some experimenting. I thought a good place to start would be the UNSW AOS project (17 years after I first did it) - but with no more ODROID-C2, got a hold of an ODROID-C4 and figured that would be a good project in itself (and well timed with a Sydney lockdown). So - good news: The peripheral devices we need are all very similar to a C2, so by getting a new DTS file and updating a few addresses it starts off fairly happily. sel4-test builds and runs (All is well...); so does the camkes adder app; and with some mods to provide enough slots (maybe because it has 4GB rather than 2GB) I have got the AOS milestone 0 stub to run (including the uart initialisation). (More work to actually finish m0 and keep going, but a job for later) But then: I moved onto the util_libs / libplatsupport project to try and port over as much of the device settings as possible; and using the camkes app serialserver_polling, under the hood using SerialServer, I can't get the uart to initialiise (or more strictly can't get the uart address to map). chardev_map / ps_io_map fails, returning a vaddr of 0. I've added a bunch of debug prints to the process; and for comparison also run it on QEMU emulating a Sabre board. On odroidc4 hardware: ## Starting application at 0x01080000 ... ELF-loader started on CPU: ARM Ltd. Cortex-A55 r1p0 paddr=[95e000..d5710f] No DTB passed in from boot loader. Looking for DTB in CPIO archive...found at a86de8. Loaded DTB from a86de8. paddr=[23f000..24afff] ELF-loading image 'kernel' to 0 paddr=[0..23efff] vaddr=[ffffff8000000000..ffffff800023efff] virt_entry=ffffff8000000000 ELF-loading image 'capdl-loader' to 24b000 paddr=[24b000..563fff] vaddr=[400000..718fff] virt_entry=408e48 Enabling MMU and paging Jumping to kernel-image entry point... Bootstrapping kernel Booting all finished, dropped to user space pre_init@serial.c:501 About to init port, io_ops=0x487cf0 ps_cdev_init@chardev.c:46 About to init_fn 3 ps_cdev_init@chardev.c:47 dev_defn[3].paddr: 0xff803000, size 1000 uart_init@serial.c:51 about to chardev_map: dev=0x473948, defn->id=3, defn->padd r=0xff803000 chardev_map@chardev.h:26 ops->io_mapper=0x487be0 &(ops->io_mapper)=0x442728 dev- >paddr=0xff803000 dev->size=0x1000 uart_init@serial.c:56 chardev_map mapped page_vaddr 0 plat_pre_init@plat.c:64 Failed to initialise character device plat_pre_init@plat.c:65 PS_SERIAL_DEFAULT: 3 On Sabre QEMU: ./simulate: qemu-system-arm -machine sabrelite -nographic -serial null -serial mon:stdio -m size=1024M -kernel images/capdl-loader-image- arm-imx6 ELF-loader started on CPU: ARM Ltd. Cortex-A9 r0p0 paddr=[106fc000..10aa98e3] No DTB passed in from boot loader. Looking for DTB in CPIO archive...found at 107fe33c. Loaded DTB from 107fe33c. paddr=[1003d000..10047fff] ELF-loading image 'kernel' to 10000000 paddr=[10000000..1003cfff] vaddr=[e0000000..e003cfff] virt_entry=e0000000 ELF-loading image 'capdl-loader' to 10048000 paddr=[10048000..10300fff] vaddr=[10000..2c8fff] virt_entry=187f8 Enabling MMU and paging Jumping to kernel-image entry point... Bootstrapping kernel Warning: Could not infer GIC interrupt target ID, assuming 0. Booting all finished, dropped to user space pre_init@serial.c:501 About to init port, io_ops=0x69cf0 ps_cdev_init@chardev.c:45 About to init_fn 1 ps_cdev_init@chardev.c:46 dev_defn[1].paddr: 0x21e8000, size 1000 uart_init@serial.c:224 about to chardev_map: dev=0x7f8c8, defn->id=1, defn->paddr=0x21e8000 chardev_map@chardev.h:26 ops->io_mapper=0x69cf0 &(ops->io_mapper)=0x1f328 dev->paddr=0x1f654 dev->size=0x4ebc4 uart_init@serial.c:226 chardev_map mapped vaddr 0xbb000 pollcli: Hello Serial Server! pollcli: abc This has me confused - it's good it works, but I can't follow in the flow how the paddr gets changed from the value supplied to chardev_map (ie 0x21e80000 becomes 0x1f654), yet in that case it works. Or is it a complication of using QEMU? A similar kind of test with AOS on odroidc4 - particularly the success of "*uart_init@uart.c:35 Mapped uart paddr:ff803000 size:1000 vaddr:b0000000*" ## Starting application at 0x01080000 ... ELF-loader started on CPU: ARM Ltd. Cortex-A55 r1p0 paddr=[88a000..c2b10f] No DTB passed in from boot loader. Looking for DTB in CPIO archive...found at 9f3068. Loaded DTB from 9f3068. paddr=[247000..252fff] ELF-loading image 'kernel' to 0 paddr=[0..246fff] vaddr=[ffffff8000000000..ffffff8000246fff] virt_entry=ffffff8000000000 ELF-loading image 'sos' to 253000 paddr=[253000..48cfff] vaddr=[400000..639fff] virt_entry=4172e0 Enabling MMU and paging Jumping to kernel-image entry point... Bootstrapping kernel Booting all finished, dropped to user space SOS Starting... <<seL4(CPU 0) [handleInterruptEntry/52 T0xffffff803fff8400 "SOS:root" @400630]: Spurious interrupt!>> <<seL4(CPU 0) [handleInterruptEntry/52 T0xffffff803fff8400 "SOS:root" @400630]: Spurious interrupt!>> <<seL4(CPU 0) [handleInterruptEntry/52 T0xffffff803fff8400 "SOS:root" @400630]: Spurious interrupt!>> <<seL4(CPU 0) [handleInterruptEntry/52 T0xffffff803fff8400 "SOS:root" @400630]: Spurious interrupt!>> <<seL4(CPU 0) [handleInterruptEntry/52 T0xffffff803fff8400 "SOS:root" @400630]: Spurious interrupt!>> <<seL4(CPU 0) [handleInterruptEntry/52 T0xffffff803fff8400 "SOS:root" @400630]: Spurious interrupt!>> <<seL4(CPU 0) [handleInterruptEntry/52 T0xffffff803fff8400 "SOS:root" @400630]: Spurious interrupt!>> uart_init@uart.c:35 Mapped uart paddr:ff803000 size:1000 vaddr:b0000000 SOS Started! test_cspace@tests.c:59 Test cspace run_tests@tests.c:174 Root CSpace test passed! test_cspace@tests.c:59 Test cspace run_tests@tests.c:182 Single level cspace test passed! test_cspace@tests.c:59 Test cspace cspace_alloc_slot@cspace.c:335 Cspace is full! run_tests@tests.c:195 Double level cspace test passed! run_tests@tests.c:199 DMA test passed! run_tests@tests.c:203 Frame table test passed! Network init dwmac.b0002000 Waiting for PHY auto negotiation to complete........ done Speed: 1000, full duplex Protocol ethernet registered (layer: 2). Protocol ipv4 registered (layer: 3). Protocol ipv6 registered (layer: 3). Protocol icmp4 registered (layer: 4). Protocol icmp6 registered (layer: 4). Protocol igmp registered (layer: 4). Protocol udp registered (layer: 4). Protocol tcp registered (layer: 4). Assigned ipv4 0.0.0.0 to device sos picotcp DHCP client: update link Assigned ipv4 192.168.200.125 to device sos picotcp DHCP client: renewal time (T1) 43200 DHCP client: rebinding time (T2) 75600 DHCP client: lease time 86400 DHCP client: netmask 255.255.255.0 DHCP client: gateway 192.168.200.4 Timer init Start first process Starting ttytest at 0x4001c8 SOS entering syscall loop aos: Error attempting syscall 29 task: Hello world, I'm tty_test! handle_syscall@main.c:128 Unknown syscall 1 <<seL4(CPU 0) [receiveIPC/148 T0xffffff803fff8400 "SOS:root" @407a48]: Reply obj ect already has unexecuted reply!>> In this case it has worked, sos_map_device works as expected (although the spurious interrupts are another task to figure out). But trying to understand what's really going on underneath ps_io_map and ultimately why libplatsupport won't work for me has got me confused. Any ideas would be appreciated. Regards Rob

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camkes-vm-linux kernel example
by Hugo V.C. 01 Jul '21

01 Jul '21

Hi, just a simple question: why this tutorial: https://docs.sel4.systems/Tutorials/camkes-vm-linux.html shows this output: Welcome to Buildroot buildroot login: root Password: # grep poke /proc/devices # figure out the major number of our driver 244 poke # mknod /dev/poke c 244 0 # create the special file # echo > /dev/poke # write to the file [ 57.389643] hi -sh: write error: Bad address # the shell complains, but our module is being invoked! I'm not getting the shell complain error, just this: # grep poke /proc/devices 247 poke # mknod /dev/poke c 247 0 # echo > /dev/poke [ 138.946905] TOC TOC NEO... # FYI: my kernel is a custom compiled one but same version as the pre-compiled you provide: # uname -a Linux buildroot 4.9.189 #4 SMP Thu Jun 24 00:16:49 CEST 2021 aarch64 GNU/Linux Any hint? Cheers,

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How will drivers work?
by Isaac Beckett 01 Jul '21

01 Jul '21

Hello! Operating system noob here, I understand that in most mainstream operating systems (Linux, BSDs, MacOS, Windows) drivers are part of the kernel. And in micro kernel operating systems like Minix and seL4, drivers are part of user space. But Minix is a lot closer to a traditional POSIX kernel, and seems to implement some of that (IE posix threads, IPC) in the kernel, which makes the environment for a driver programmer a bit more familiar. How do drivers work in seL4, then? How does a driver obtain permission for hardware access from the kernel? I imagine it works with a capability delegated by the root task, but how do you solve chicken and the egg type problems, like loading driver code, without driver code already loaded? Is it an initramfs like Linux/Unix? Also, what if seL4 is being used _as_ the firmware/bootloader? Obviously it can load the seL4 kernel and user space OS components from a file system to put them in the booting OS’ memory, but how does it load drivers for itself? I’m assuming there’s some low level platform specific code, but is that code verified or part of the proofs?

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Re: Tutorial Problem
by Peter Chubb 30 Jun '21

30 Jun '21

>>>>> "Michael" == Michael Neises <neisesmichael(a)gmail.com> writes: Michael> Peter, When I try to remove vme from the -cpu line, I get the Michael> following error at simulation time: OK, so you need nested virtualisation. That's not supported in code-translation mode, only when you're using the KVM kernel module. The message you got was about the simulated CPU, not your host. If you can enable KVM, qemu will pass through your host to the simulation. Looks like you have the kernel packages installed, now you need to make sure that: 1, The version of qemu you're using supports KVM, and 2. you have permissions to use KVM. The first is easy. On Debian-derived systems (debian, ubuntu, mint, etc) sudo apt install qemu-kvm should do the trick. Similarly sudo yum install qemu-kvm on Redhat-derived systems. The second is a little harder. Do ls -l /dev/kvm You'll see something like crw-rw----+ 1 root kvm 10, 232 Jun 30 09:13 /dev/kvm if kvm is installed. The second username (in this case, 'kvm') is the group you need to be in. Do sudo useradd your-login kvm (replacing 'kvm' with the actual group /dev/kvm is in, and 'your-login' with you local login name.) qemu-system-x86_84 -enable-kvm should then work. Peter C -- Dr Peter Chubb https://trustworthy.systems/ Trustworthy Systems Group CSE, UNSW

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Tutorial Problem
by Michael Neises 30 Jun '21

30 Jun '21

Hello everyone, The tutorials provided here are failing to build for me: https://github.com/seL4/sel4-tutorials Here are the steps to reproduce the errors: git clone git@github.com:seL4/seL4-CAmkES-L4v-dockerfiles.git && git clone git@github.com:seL4/sel4-tutorials.git && make -C ./seL4-CAmkES-L4v-dockerfiles user HOST_DIR=$(pwd)\ followed by cd sel4-tutorials && mkdir build && cd build && ../init.py --plat pc99 --tut camkes-vm-linux Then I am met with the error: ERROR:root:Parent directory is not tutorials root directory which I can fix by changing this line to read "init.py": https://github.com/seL4/sel4-tutorials/blob/d040028999b83c6af2309785f746810… Trying again after this edit, I meet the following errors: loading initial cache file ../projects/sel4-tutorials/settings.cmake CMake Error: Error processing file: ../projects/sel4-tutorials/settings.cmake CMake Error: The source directory "/host/sel4-tutorials/build" does not appear to contain CMakeLists.txt. Specify --help for usage, or press the help button on the CMake GUI. Traceback (most recent call last): File "../init.py", line 90, in <module> sys.exit(main()) File "../init.py", line 78, in main result = common.init_directories(args.plat, args.tut, args.solution, File "/host/sel4-tutorials/common.py", line 101, in init_directories return _init_build_directory(config, initialised, build_directory, tute_directory, output, config_dict=config_dict) File "/host/sel4-tutorials/common.py", line 69, in _init_build_directory return sh.cmake(args + [tute_directory], _cwd=directory, _out=output, _err=output) File "/usr/local/lib/python3.8/dist-packages/sh.py", line 1520, in __call__ return RunningCommand(cmd, call_args, stdin, stdout, stderr) File "/usr/local/lib/python3.8/dist-packages/sh.py", line 784, in __init__ self.wait() File "/usr/local/lib/python3.8/dist-packages/sh.py", line 841, in wait self.handle_command_exit_code(exit_code) File "/usr/local/lib/python3.8/dist-packages/sh.py", line 865, in handle_command_exit_code raise exc sh.ErrorReturnCode_1: RAN: /usr/bin/cmake -G Ninja -DTUT_BOARD=pc -DTUT_ARCH=x86_64 -DFORCE_IOMMU=ON -DTUTORIAL_DIR=build -C ../projects/sel4-tutorials/settings.cmake /host/sel4-tutorials/build STDOUT: STDERR: Either I'm missing something obvious or these instructions have fallen out of date. In any case I would be grateful for any advice. Best, Michael Neises

4 5

How to avoid seL4 passing packets to Linux VM guest
by Hugo V.C. 25 Jun '21

25 Jun '21

Hi, I wonder how to have seL4 host not passing network frames to Linux VM guest. I mean, I would like to have seL4 dealing with TCP/IP and processing packets at the host level but then I want to use a custom communication channel with the Linux guest. So, the very first step would be to stop forwarding network frames to the guest. Any hint where I can start experimenting with this? Cheers,

2 4

Some small details in kernel code and docs
by Mark Jones 24 Jun '21

24 Jun '21

Hi All, Here are a few minor details/questions about the kernel code & documentation. (I've confirmed that these are present in the new seL4-12.1.0 release.) 1) kernel/include/arch/x86/arch/32/mode/machine.h has the following definition (some code elided): static inline word_t FORCE_INLINE x86_read_fs_base_impl(void) { word_t base = 0; base &= ...; base &= ...; base &= ...; return base; } I'm pretty sure that the three &= operators here should be |= or else the result is always going to be zero. The same issue occurs in x86_read_gs_base_impl in the same file. Some follow-up questions: Can anyone say if this would have been detected if the PC99 (32-bit) platform had been verified? More generally, where can I find information about how ia32 segment registers are handled by the kernel? Why aren't they just stored/restored like other user-level registers on kernel entry/exit? Is there something that prevents user-level changes in the ES register, for example, from being observed in other threads? 2) A CNodeRotate will generate a FailedLookup error if the pivot slot either doesn't exist or contains a null capability. But, in the first case the "lookup failed for a source capability" field in the error message is 1, while in the second it is 0. Hardly a serious problem, but this does seem inconsistent. Is this intentional, or a mistake in the specification that has been carried over to the implementation? 3) Section "3.4 Lookup Failure Description" of the manual describes how capability lookup errors are represented in an IPC buffer. But it seems the layout information is incorrect. For example, Section 3.4.2 says that "Offset + 0" will contain seL4_MissingCapability while the number of bits left will be at "Offset + seL4_CapFault_BitsLeft", which is probably supposed to be equivalent to "Offset + 1". But, based on kernel/libsel4/include/sel4/shared_types.h, it would seem that this gives "Offset + 4". Sections 3.4.3 and 3.4.4 have similar problems. 4) On https://docs.sel4.systems/GettingStarted, in the section labeled "Fetching, Configuring and Building seL4test", there are missing line breaks between the commands in the text boxes for Steps 1 and 2, and there are some tags in the text box for Step 4 that probably should not be displayed. Best wishes, and thanks for any feedback! Mark

6 7

CAmkES ARM VM: SATA Passthrough
by Olof Holmberg 21 Jun '21

21 Jun '21

Hi, I ran into the issue of not being able to fit the whole rootfs in RAM (using a qemu-arm-virt device). Therefore I opted for booting the initramfs instead and from there switch root to the proper file system. The booting of the initramfs works fine but the /dev/sda device is not visible to the guest. For x86 (according to these instructions: https://docs.sel4.systems/projects/camkes-vm/) this seems to be done by passing through access to the SATA controller. But since the x86 device configuration is different to the ARM device configuration it requires a different config than the one shown in the instructions. I was wondering how you achieve this SATA passthrough for a ARM VM or if there are any tutorials, other projects or examples that shows how it is done? Best regards, Olof

2 1

Re: Devel Digest, Vol 104, Issue 8
by jonas.cl＠protonmail.com 14 Jun '21

14 Jun '21

Sent from ProtonMail, Swiss-based encrypted email. ‐‐‐‐‐‐‐ Original Message ‐‐‐‐‐‐‐ On Monday, June 14, 2021 4:00 AM, <devel-request(a)sel4.systems> wrote: > Send Devel mailing list submissions to > devel(a)sel4.systems > > To subscribe or unsubscribe via email, send a message with subject or > body 'help' to > devel-request(a)sel4.systems > > You can reach the person managing the list at > devel-owner(a)sel4.systems > > When replying, please edit your Subject line so it is more specific > than "Re: Contents of Devel digest..." > > Today's Topics: > > 1. sel4 camkes stability (mrshafiei(a)aut.ac.ir) > 2. sel4 camkes stability mechanisms for crash handling and thread failure > (mrshafiei(a)aut.ac.ir) > > > Message: 1 > Date: Sun, 13 Jun 2021 10:47:43 +0430 > From: mrshafiei(a)aut.ac.ir > Subject: [seL4] sel4 camkes stability > To: Siwei.Zhuang(a)data61.csiro.au, devel(a)sel4.systems > Message-ID: 1623565063345060169(a)aut.ac.ir > > Content-Type: text/plain; charset="utf-8" > > Hi Siwei. > I have some problem with my sel4 project, as you know, I'm work on my master project and develop a project on sel4 (camkes) which provide filesystem interfaces, and use ethernet and lwip network stack. This section is ok but sometimes my project crashed and my threads failed. I think that you should start by getting core files from all the crashes. This will point to why the threads fail. I haven't done that for projects running seL4 on hardware, but it is easy to connect gdb to an image running in qemu. I'm sure someone here can point you in the right direction on how to catch core-dump files from hardware. You can of course also implement a watchdog, but start with solving the crashes. /Jonas Claesson > In another words, I wrote my > components and its work correctly but some times (rarely) my threads > crashes and I couldn't find problem. So i decide to use a service like > watch dog timer for garanty all of threads work and when one of therm > failed or crashed, this mechanism detect it and start another thread or > reset the system. > A simple solution can implement is use some thread controlling > (implement WDT in user mode). But I want to know is there in camkes or > sel4 any mechanism for this need? a mechanism for garanti stability and > system availability? > can any body help me? > Is there anybody which confront with this need? > > -------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------- > > This email was Anti Virus checked by Security Gateway. > > ------------------------------------------------------- > > Message: 2 > Date: Sun, 13 Jun 2021 10:50:18 +0430 > From: mrshafiei(a)aut.ac.ir > Subject: [seL4] sel4 camkes stability mechanisms for crash handling > and thread failure > To: devel(a)sel4.systems > Message-ID: 1623565218534753237(a)aut.ac.ir > > Content-Type: text/plain; charset="utf-8" > > Hi there. > I have some problem with my sel4 project, as > you know, I'm work on my master project and develop a project on sel4 > (camkes) which provide filesystem interfaces, and use ethernet and lwip > network stack. This section is ok but sometimes my project crashed and > my threads failed. > In another words, I wrote my > components and its work correctly but some times (rarely) my threads > crashes and I couldn't find problem. So i decide to use a service like > watch dog timer for garanty all of threads work and when one of therm > failed or crashed, this mechanism detect it and start another thread or > reset the system. > A simple solution can implement is use some thread controlling > (implement WDT in user mode). But I want to know is there in camkes or > sel4 any mechanism for this need? a mechanism for garanti stability and > system availability? > can any body help me? > Is there anybody which confront with this need? > > -------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------- > > This email was Anti Virus checked by Security Gateway. > > ------------------------------------------------------- > > Subject: Digest Footer > > Devel mailing list -- devel(a)sel4.systems > To unsubscribe send an email to devel-leave(a)sel4.systems > > > --------------------------------------------------------------------------------------------------- > > End of Devel Digest, Vol 104, Issue 8

1 0

MMC wait after second command in intialization with mmc_init
by MOHAMAD REZA SHAFIEI 13 Jun '21

13 Jun '21

hi there . i'm work on mmc storage with sel4. i wrote a simple app that use mmc an here is that : ////////////////////////////////////////////////////////////////////// static int count = 0; ps_io_ops_t io_ops = {0}; struct netif* net_if; mmc_card_t mmc_card = 0; sdio_host_dev_t sdio_host_dev; int mmc_found = 0; void mmc_irq_handle(ps_irq_t* irq) { printf("mmc irq handle .... \n"); if(!mmc_found){ mmc_irq_acknowledge(irq); // printf("mmc not found yet :)\n"); sdio_host_dev.handle_irq(&sdio_host_dev,irq->irq.number); return ; } mmc_irq_acknowledge(irq); mmc_handle_irq(mmc_card,irq->irq.number); } int run(void) { notification = timer_notification(); int err = camkes_io_ops(&io_ops); if (err != 0) { ZF_LOGF("Can not init ops : %d\n", err); }; printf("initialize sdhc1 ...\n"); err = sdio_init(SDHC1, &io_ops, &sdio_host_dev); // while card not present check while(sdio_host_dev.reset(&sdio_host_dev) == -1){ delay(1000); } printf("before mmc_init\n"); mmc_init(&sdio_host_dev, &io_ops, &mmc_card); mmc_found = 1; printf("after mmc_init\n"); if (!err) { printf("SDHC1 inited successfully.\n"); } else { printf("SDHC1 initizatino failed!: %d", err); } while (true) { printf(".\n"); delay(1000); } return 0; //////////////////////////////////////////////// its work but in mmc_init after going to mmc_reset , first command sent but in second command (ie MMC_SEND_EXT_CSD ) wait for ever... can any body help me? best regards -- This email was Anti Virus checked by Security Gateway.

2 1

lighttpd as non root user in sel4webserver demo
by Hugo V.C. 13 Jun '21

13 Jun '21

Hi, I was trying to run lighttpd as non root user in " https://github.com/seL4/sel4webserver" demo and realized it didn't allowed me no matter if I configured /etc/passwd, /etc/group and /etc/shadow and /etc/lighttpd.conf correctly. As I don't have debug tools in this Linux VM to look what's going on I decided to directly modify the lighttpd source code to bypass some native code of the web server and hardcode my own user/group. Looks like it works and I now have lighttpd running with it's own user: # ps -ef PID USER COMMAND 1 root init (...) 60 root /sbin/syslogd -n 64 root /sbin/klogd -n 108 lighttpd lighttpd -f /etc/lighttpd.conf 110 root /sbin/getty -L tty1 0 vt100 (...) I also changed the ownership of the /run/site tree to be owned by root. The changes I did in the source code are basically to bypass "getgrnam()" and "getpwnam()" syscalls as I suspect for some reason (musl libc guilty??) and manually set the setgid value before the chroot. I know this is a very dirty hack... but it works for me. My question is if anyone thinks this can be useful to others I can create a pull request with the changes. I think that even if this is a demo, it is not nice to run lighttpd as root, even for a static website. Of course the "right"/elegant way of solving this would be not to change lighttpd source code... but I was unable to do that way. Let me know your opinions. Cheers,

1 0

Camkes-vm-linux on
by Hugo V.C. 12 Jun '21

12 Jun '21

Hi, I'm trying the camkes-vm-linux tutorial and can't run it in qemu despite having nested guests enabled: hugo@dev:~/seL4/sel4-tutorials-manifest/camkes-vm-linux_build$ cat /sys/module/kvm_intel/parameters/nested Y --------- hugo@dev:~/seL4/sel4-tutorials-manifest/camkes-vm-linux_build$ sudo ./simulate --machine q35,accel=kvm,kernel-irqchip=split --mem-size 2G --extra-cpu-opts "+vmx" --extra-qemu-args="-enable-kvm -device intel-iommu,intremap=off -net nic,model=e1000 -net tap,script=no,ifname=tap0" ./simulate: qemu-system-x86_64 -machine q35,accel=kvm,kernel-irqchip=split -cpu Nehalem,+vme,+pdpe1gb,-xsave,-xsaveopt,-xsavec,-fsgsbase,-invpcid,+syscall,+lm,enforce,+vmx -nographic -serial mon:stdio -m size=2G -enable-kvm -device intel-iommu,intremap=off -net nic,model=e1000 -net tap,script=no,ifname=tap0 -kernel images/kernel-x86_64-pc99 -initrd images/capdl-loader-image-x86_64-pc99 qemu-system-x86_64: warning: host doesn't support requested feature: CPUID.80000001H:EDX.pdpe1gb [bit 26] qemu-system-x86_64: warning: host doesn't support requested feature: MSR(48FH).vmx-exit-load-perf-global-ctrl [bit 12] qemu-system-x86_64: warning: host doesn't support requested feature: MSR(490H).vmx-entry-load-perf-global-ctrl [bit 13] qemu-system-x86_64: Host doesn't support requested features ./simulate: QEMU failed; resetting terminal in 5 seconds--interrupt to abort --------- any tutorial to build/boot it natively on x86_64? Thanks,

2 1

Clean repo init
by Hugo V.C. 11 Jun '21

11 Jun '21

Hi, I'm trying to start a new "clean" repo init in my "/seL4/sel4webserver" directory so I deleted everything there, then I executed: repo forall -c "git reset --hard HEAD" repo forall -c "git clean -df" the I executed: repo init -u https://github.com/SEL4PROJ/sel4webserver-manifest.git repo sync but when I go to the "/projects/webserver/lighttpd" directory and check the content of local "lighttpd.sh" I see different (old) content than what you can see via web interface here: https://github.com/seL4/sel4webserver/blob/master/lighttpd/lighttpd.sh Specifically, via web interface I can see the recent commit: https://github.com/seL4/sel4webserver/commit/6a98bdcb2be6ffc693325bbb48df9d… but in my local copy of the file I can't see the changes. Is it due to come kind of cache issue of Git...? Does it require some time to be synced what you see via web interface and what you get downloaded via CLI? Am I doing something wrong? Thank you in advance and sorry for this newbie like question. Hugo

3 3

Proving there exists a valid execution of a function
by Ben Fiedler 11 Jun '21

11 Jun '21

Hi seL4 devs, I'm not sure whether this list is the right spot to ask about AutoCorres issues, but I gather you have some experience with that :-) I'm currently working on proving that some CAmkES component behaves well wrt some higher- level specification. I want to prove this by simulation: Each step of my concrete CAmkES code corresponds to a step of some abstract machine. I've proven the behavioural lemmas as Hoare-triples using the validNF framework, and now want to lift the AutoCorres-generated executions to my higher-level representation. I'm having issues with this however. Concretely, I want to be able to extract some resulting state after e.g. execution function f. For example: I have the following triple: {| P |} f {| Q |}! Now given a state s such that P s is satisfied, I want to obtain some resulting state s' such that Q' _ s' holds. This is easy enough, as Isabelle has Hilbert's choice operator: fun get_next_state where "get_next_state f s = SOME s'. s' : (snd ` fst (f s))" Here is my problem: The choice operator only works when selecting from a non-empty set. I have a feeling that since I've shown that {P} f {Q} is a non-failing and valid hoare-triple this should somehow follow, but it doesn't. There is an easy counter-example: {| top |} select {} {| toptop |} This is a valid triple, however there are no valid executions for `select {}`. I have a feeling that this is the only counterexample though, since all other potential sources of empty executions are covered (namely nonterminating while loops, as they must always terminate in the validNF framework). If `select A` included a guard that A is non-empty, then I believe one could show that vaildNF P f Q implies exs_valid P f Q, although I'm not sure on this. I've looked into the exs_valid framework, which proves exactly what I want. However, I have two issues with this: 1. I have already proven all the invariants I wanted in the validNF framework, and repeating these proofs seems redundant to me. 2. The exs_valid framework has very little utilities provided for use with the wp tool, which makes working with it more tedious than the validNF framework. Another avenue I've looked at is using termination proofs from the SIMPL code: The AutoCorres ac_corres lemmas derived for my functions guarantee termination of the concrete SIMPL code if the abstract version does not fail, which I have proven. Since, as far as I understand it, the SIMPL layer has no problematic `select`-equivalent, termination should be sufficient to guarantee that a following state actually exists, and somehow lifting that guarantee to the AutoCorres layer. I haven't had success with this though. Any help/pointers is appreciated. Thanks a lot in advance! Cheers, Ben

1 1

Increase Initrd Max Size Beyond DTB Address Limitation
by Olof Holmberg 10 Jun '21

10 Jun '21

Hi, I was wondering if there is a way to increase the RAM size of the Initrd in the qemu-arm-virt VM to more than the initially allowed which seems to be around 250MB. These are my current settings for the VM RAM: #define VM_RAM_OFFSET 0x00000000 #define VM_INITRD_MAX_SIZE 0x9000000 // 150 MB #define VM_RAM_BASE 0x40000000 #define VM_RAM_SIZE 0x20000000 #define VM_DTB_ADDR 0x4F000000 // VM0_RAM_BASE + 0xF000000 #define VM_INITRD_ADDR 0x46000000 // VM0_DTB_ADDR - VM_INITRD_MAX_SIZE And what I would want is something like this: #define VM_RAM_OFFSET 0x00000000 #define VM_INITRD_MAX_SIZE 0x20000000 // 500 MB #define VM_RAM_BASE 0x40000000 #define VM_RAM_SIZE 0x30000000 #define VM_DTB_ADDR 0x6F000000 // VM0_RAM_BASE + 0xF000000 #define VM_INITRD_ADDR 0x4F000000 // VM0_DTB_ADDR - VM_INITRD_MAX_SIZE VM_DTB_ADDR should probably be 0x4F000000. If I interpreted it correctly it means that the VM_INITRD_ADDR will be below the VM_RAM_BASE_ADDR and therefore outside of the allocated memory for the VM. But I assume that the comments regarding the address of the DTB that it is not possible to have a larger size of Initrd than the difference between VM_DTB_ADDR and the VM_RAM_BASE allows for. I have tested with some different configurations and it either results in the boot hanging after touching the pages for the VM or results in a page error during the touching of pages. It however seems to work with having the VM_INITRD_MAX_SIZE larger than what could fit between the base and Initrd address but I assume that it would result in an error should the actual loaded initramfs require the whole allocated space. What would be the correct way to achieve this if it is even possible? I assume that it might not even be possible if the addresses that has to be allocated for the larger Initrd is already used and allocated for other things. Best regards, Olof

1 0

Running vm_multi on TK1 and TX2
by Mike Clark 10 Jun '21

10 Jun '21

The camkes-vm-examples readme mentions that the Nvidia TX2 should support multiple VMs but it is untested. If you try to build the vm_multi app for TX2 you just get an error that the platform is unsupported. Has anyone tried vm_multi on TX2? Do you have a working devices.camkes that you can share? On the TK1 board, the readme says multiple VMs is unsupported, but in the Notes it says that Multi-VM is untested. Could multi-vm work for TK1? Mike

1 0

Bug when compling in release mode
by Ben Fiedler 09 Jun '21

09 Jun '21

Hello everyone, I've recently found an interesting bug that only occurs when compiling in release mode. Use of the ZF_LOG library (for normal log output) leads to syscalls being made when the capdl-loader runs. These are invoked via musllibc's __stdio_write, which relies on __sysinfo being set correctly for syscalls to work. When compiling with RELEASE=OFF this works fine, however when compiling with RELEASE=ON, __sysinfo is not set (yet?), and subsequently leads to an illegal prefetch exception when __stdio_write tries to invoke a syscall. Setting __sysinfo to sel4_vsyscall using gdb during runtime fixes this. I don't really know the correct place to fix this in the code, but I hope that you can provide some hints on where to fix this bug. Thanks a lot for your help! Cheers, Ben

2 2

Pull request of S91lighttpd
by Hugo V.C. 08 Jun '21

08 Jun '21

Hi, I'm trying to make a pull request as I want to make a very simple (yet useful) change to S91lighttpd file. I wonder where I can find this file in Git as I can find it locally in my build directory: build/overlay/etc/init.d/S91lighttpd but can not find it anywhere else in Git. I assume it is part of some prebuilt file system (overlay?) but still I can't find where this file system is in Git. Any help will be appreciated. Hugo

2 2

Status of the seL4 RISC-V platform Rocketchip
by Axel Heider 07 Jun '21

07 Jun '21

Hi, I'm wondering about the state of the seL4 RISC-V platform "Rocketchip", is anybody actively using this? At the seL4 hardware status page https://docs.sel4.systems/Hardware/rocketchip.html there is not much, and the repo https://github.com/ucb-bar/fpga-zynq has been abandoned. It points to https://github.com/sifive/freedom which has also been abandoned recently. So I wonder, is this platform effectively dead and should be removed? Axel

1 0

watch dog timer and stability mechanisms in sel4 and camkes
by MOHAMAD REZA SHAFIEI 05 Jun '21

05 Jun '21

Hi there. i'm working on my master project and try to implement a system which act as a storage system (a simple sample). so i write my components and its work correctly but some times (rarely) my threads crashes and I couldn't find problem. So i decide to use a service like watch dog timer for garanti all of threads work and when one thread failed and crashed, this mechanism detect it and start another thread or reset the system. My project is on sle4 and camkes framework, a simple solution can implement by some thread controlling (implement WDT in user mode). But I want to know is there in camkes or sel4 any mechanism for this need? a mechanism for garanti stability and system availability? can any body help me? Is there anybody which confront with this need? -- This email was Anti Virus checked by Security Gateway.

1 0

libsel4utils: load_segment memory leak bug
by wzt wzt 05 Jun '21

05 Jun '21

hello: i found a bug memory leak bug in libsel4utils/src/elf.c static int load_segment(vspace_t *loadee_vspace, vspace_t *loader_vspace, vka_t *loadee_vka, vka_t *loader_vka, const char *src, size_t file_size, int num_regions, sel4utils_elf_region_t regions[num_regions], int region_index) { seL4_CPtr loader_slot; cspacepath_t loader_frame_cap; error = vka_cspace_alloc(loader_vka, &loader_slot); [1] while (pos < segment_size && error == seL4_NoError) { reservation_t reservation; if (loadee_vaddr < region.reservation_vstart) { if ((region_index - 1) < 0) { ZF_LOGE("Invalid regions: bad elf file."); return 1; [2] } } if [2] happned, it not free the prev alloc memory, and then it's memory will be leaked. i think the correct way is invoke vka_cspace_free() before return.

3 2

Mapping VM Kernel Memory
by Michael Neises 05 Jun '21

05 Jun '21

Hello everyone, I have a question about some code I'm using from the seL4 repositories. I have a follow-up question about whether a certain memory mapping strategy is feasible. I'm looking at this kernel module: https://github.com/seL4/camkes-vm-linux/blob/master/camkes-linux-artifacts/… and at this user-space app: https://github.com/seL4/camkes-vm-linux/blob/master/camkes-linux-artifacts/… In short, there is shared memory between a camkes component and the vm-linux. I can tell that the shared memory region is given by accessing /dev/uio0. However, it's not clear to me what exactly this memory region is. As I simulate the kernel, I find this: [ 0.000000] Virtual kernel memory layout: [ 0.000000] modules : 0xffff000000000000 - 0xffff000008000000 ( 128 MB) [ 0.000000] vmalloc : 0xffff000008000000 - 0xffff7dffbfff0000 (129022 GB) [ 0.000000] .text : 0xffff000008080000 - 0xffff0000087d0000 ( 7488 KB) [ 0.000000] .rodata : 0xffff0000087d0000 - 0xffff000008a50000 ( 2560 KB) [ 0.000000] .init : 0xffff000008a50000 - 0xffff000008e00000 ( 3776 KB) [ 0.000000] .data : 0xffff000008e00000 - 0xffff000008f31200 ( 1221 KB) [ 0.000000] .bss : 0xffff000008f31200 - 0xffff000008fb9034 ( 544 KB) [ 0.000000] fixed : 0xffff7dfffe7fb000 - 0xffff7dfffec00000 ( 4116 KB) [ 0.000000] PCI I/O : 0xffff7dfffee00000 - 0xffff7dffffe00000 ( 16 MB) [ 0.000000] vmemmap : 0xffff7e0000000000 - 0xffff800000000000 ( 2048 GB maximum) [ 0.000000] 0xffff7e0000000000 - 0xffff7e0000200040 ( 2 MB actual) [ 0.000000] memory : 0xffff800000000000 - 0xffff800008001000 ( 128 MB) My belief is that /dev/uio0 points to the section here labeled "memory." Is that right? My goal is to perform memory introspection on vm-linux kernel modules. To that end, I think I want to look at the section labeled "modules." Is that possible? Best, Michael Neises

1 0

QEMU simulation: Passing drive to CAmkES ARM VM
by Olof Holmberg 04 Jun '21

04 Jun '21

Hi, I am currently booting a initramfs as the VM so that I later would be able to switch root to a filesystem disk that allows for larger storage and has other software installed that I want inside the VM. I have started the simulate script with a few variants of the following line (Passing the virtio device was a guess since the virtio-net device is supported for networking for the VM. I have also tried to pass only the drive part but it has the same result.): sudo ./simulate --extra-qemu-args="-device virtio-blk-pci,drive=drive0 -drive file=filesystem/testimage,format=raw,if=none,id=drive0" However there are no devices appearing in /dev/ that seem to be the drive passed to qemu such as sdaX or vdaX. There is no output from running "fdisk -l" either. So therefore I wonder if this kind of passthrough is supported by seL4? I have tried to find documentation that relates passing a disk to the VM in seL4 but have not found anything yet. This was done for the qemu-arm-virt platform if that has some significance regarding platform support. Best regards, Olof

2 2

Running ninja twice fails in https://github.com/seL4/sel4webserver
by skydivebcn＠gmail.com 04 Jun '21

04 Jun '21

Hi, I have noticed I'm never unable to run "ninja" for a second time and I'm required to rm -rf all the contents of "build" directory, and run "../init-build.sh" again before running ninja again. If I try to simpley run "ninja" twice the error I get is: (...) /var/lib/gems/2.7.0/gems/jekyll-4.0.0/lib/jekyll/tags/include.rb:179: warning: Using the last argument as keyword parameters is deprecated /var/lib/gems/2.7.0/gems/jekyll-4.0.0/lib/jekyll/tags/include.rb:179: warning: Using the last argument as keyword parameters is deprecated (many times...) /var/lib/gems/2.7.0/gems/jekyll-4.0.0/lib/jekyll/tags/include.rb:179: warning: Using the last argument as keyword parameters is deprecated /home/hugo/seL4/sel4webserver/build/docsite-prefix/src/docsite/_plugins/include_absolute.rb:71: warning: Using the last argument as keyword parameters is deprecated done in 10.04 seconds. Auto-regeneration: disabled. Use --watch to enable. ninja: build stopped: subcommand failed. Any hint on what could be happening? Anyone else having same issue? I'm doing something wrong?

3 5

VGA pass-through using CAmkES VM on x86
by Nicholas Pahl 03 Jun '21

03 Jun '21

Hello all, I am working out of a CAmkES VM manifest and have a function build running on an x86 platform. I have successfully pass-through various PCIe devices (Ethernet, Sata, USB) to a RHEL8 VM. I am attempting to pass-through the VGA controller in the same way as the other PCIe devices, but I am running into errors. I am assuming VGA pass-through requires more effort than just passing the PCIe device through. If anyone has any tips for VGA pass-through or an example CAmkES project that would be greatly appreciated. Also, if anyone has VESA framebuffer pass-through working I would also be interested. I have tried using LibSel4VMMPlatsupportVESAFrameBuffer but have not had any success getting a VM to use it. The card I am trying to pass-through is a Radeon HD 3450. The kernel log's call stack indicates that it is getting into radeon initialization functions, so it does see the VGA controller on the bus. The log seems to be failing to retrieve info from the BIOS. Below is a log of the kernel panic. [ 2.472635] BUG: unable to handle kernel paging request at ffffc90000548480 [ 2.472635] PGD 1013a067 P4D 1013a067 PUD 1013b067 PMD 6fdb8067 PTE 0 [ 2.472635] Oops: 0000 [#1] SMP PTI [ 2.472635] CPU: 0 PID: 349 Comm: systemd-udevd Not tainted 4.18.0-305.el8.x86_64 #1 [ 2.472635] RIP: 0010:radeon_card_posted+0x147/0x200 [radeon] [ 2.472635] Code: 48 8b 83 e8 01 00 00 48 89 c1 83 fa 38 74 53 83 fa 26 0f 87 09 ff ff ff 83 fa 11 76 4d 8b 90 80 60 00 00 48 8b 83 e8 01 00 00 <8b> 80 80 68 00 00 09 d0 a8 01 74 9f 5b b8 01 00 00 00 5d 41 5c c3 [ 2.472635] RSP: 0018:ffffc900005f7960 EFLAGS: 00010202 [ 2.472635] RAX: ffffc90000541c00 RBX: ffff888014950000 RCX: ffffc90000541c00 [ 2.472635] RDX: 0000000016dd1440 RSI: 0000000000000296 RDI: ffff888014950000 [ 2.472635] RBP: ffffc900005f79d8 R08: 0000000000000002 R09: 0000000000000000 [ 2.472635] R10: ffffc900005f79c8 R11: ffffc90000541000 R12: 0000000000000000 [ 2.472635] R13: ffff888014951d90 R14: 0000000000000000 R15: ffff888014950000 [ 2.472635] FS: 00007fe597ad8180(0000) GS:ffff88806fc00000(0000) knlGS:0000000000000000 [ 2.472635] CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 [ 2.472635] CR2: ffffc90000548480 CR3: 0000000016444000 CR4: 00000000000006b0 [ 2.472635] Call Trace: [ 2.472635] igp_read_bios_from_vram+0x18/0xa0 [radeon] [ 2.472635] radeon_get_bios+0x2be/0xf10 [radeon] [ 2.472635] ? __debugfs_create_file+0xc1/0x120 [ 2.472635] ? __debugfs_create_file+0xd5/0x120 [ 2.472635] ? mutex_lock+0xe/0x30 [ 2.472635] ? drm_debugfs_create_files+0x104/0x120 [drm] [ 2.472635] r600_init+0x2b/0x5c0 [radeon] [ 2.472635] radeon_device_init+0x5e7/0xb70 [radeon] [ 2.472635] radeon_driver_load_kms+0x8d/0x240 [radeon] [ 2.472635] drm_dev_register+0xc6/0x1b0 [drm] [ 2.472635] radeon_pci_probe+0x12a/0x1d0 [radeon] [ 2.472635] ? __pm_runtime_resume+0x54/0x70 [ 2.472635] local_pci_probe+0x41/0x90 [ 2.472635] pci_device_probe+0x105/0x1c0 [ 2.472635] really_probe+0x255/0x4a0 [ 2.472635] driver_probe_device+0x49/0xc0 [ 2.472635] device_driver_attach+0x50/0x60 [ 2.472635] __driver_attach+0x61/0x130 [ 2.472635] ? device_driver_attach+0x60/0x60 [ 2.472635] bus_for_each_dev+0x77/0xc0 [ 2.472635] ? klist_add_tail+0x3b/0x70 [ 2.472635] bus_add_driver+0x14d/0x1e0 [ 2.472635] ? 0xffffffffc03fd000 [ 2.472635] driver_register+0x6b/0xb0 [ 2.472635] ? 0xffffffffc03fd000 [ 2.472635] do_one_initcall+0x46/0x1c3 [ 2.472635] ? do_init_module+0x22/0x220 [ 2.472635] ? kmem_cache_alloc_trace+0x131/0x270 [ 2.472635] do_init_module+0x5a/0x220 [ 2.472635] load_module+0x14c5/0x17f0 [ 2.472635] ? __switch_to_asm+0x35/0x70 [ 2.472635] ? __switch_to_asm+0x41/0x70 [ 2.472635] ? __switch_to_asm+0x35/0x70 [ 2.472635] ? __switch_to_asm+0x41/0x70 [ 2.472635] ? __switch_to_asm+0x35/0x70 [ 2.472635] ? __switch_to_asm+0x41/0x70 [ 2.472635] ? __switch_to_asm+0x35/0x70 [ 2.472635] ? __switch_to_asm+0x41/0x70 [ 2.472635] ? __do_sys_init_module+0x13b/0x180 [ 2.472635] __do_sys_init_module+0x13b/0x180 [ 2.472635] do_syscall_64+0x5b/0x1a0 [ 2.472635] entry_SYSCALL_64_after_hwframe+0x65/0xca [ 2.472635] RIP: 0033:0x7fe5966b680e [ 2.472635] Code: 48 8b 0d 7d 16 2c 00 f7 d8 64 89 01 48 83 c8 ff c3 66 2e 0f 1f 84 00 00 00 00 00 90 f3 0f 1e fa 49 89 ca b8 af 00 00 00 0f 05 <48> 3d 01 f0 ff ff 73 01 c3 48 8b 0d 4a 16 2c 00 f7 d8 64 89 01 48 [ 2.472635] RSP: 002b:00007ffc53efb408 EFLAGS: 00000246 ORIG_RAX: 00000000000000af [ 2.472635] RAX: ffffffffffffffda RBX: 00005626ca9314d0 RCX: 00007fe5966b680e [ 2.472635] RDX: 00007fe59722486d RSI: 00000000002c4878 RDI: 00005626cb200450 [ 2.472635] RBP: 00007fe59722486d R08: 00005626ca91501a R09: 0000000000000005 [ 2.472635] R10: 00005626ca915010 R11: 0000000000000246 R12: 00005626cb200450 [ 2.472635] R13: 00005626ca92d120 R14: 0000000000020000 R15: 0000000000000000 [ 2.472635] Modules linked in: radeon(+) i2c_algo_bit drm_kms_helper syscopyarea sysfillrect sysimgblt fb_sys_fops ttm drm ahci libahci e1000e(+) libata crc32c_intel dm_mirror dm_region_hash dm_log dm_mod fuse [ 2.472635] CR2: ffffc90000548480 [ 2.472635] ---[ end trace a2f824fed053010d ]--- [ 2.472635] RIP: 0010:radeon_card_posted+0x147/0x200 [radeon] [ 2.472635] Code: 48 8b 83 e8 01 00 00 48 89 c1 83 fa 38 74 53 83 fa 26 0f 87 09 ff ff ff 83 fa 11 76 4d 8b 90 80 60 00 00 48 8b 83 e8 01 00 00 <8b> 80 80 68 00 00 09 d0 a8 01 74 9f 5b b8 01 00 00 00 5d 41 5c c3 [ 2.472635] RSP: 0018:ffffc900005f7960 EFLAGS: 00010202 [ 2.472635] RAX: ffffc90000541c00 RBX: ffff888014950000 RCX: ffffc90000541c00 [ 2.472635] RDX: 0000000016dd1440 RSI: 0000000000000296 RDI: ffff888014950000 [ 2.472635] RBP: ffffc900005f79d8 R08: 0000000000000002 R09: 0000000000000000 [ 2.472635] R10: ffffc900005f79c8 R11: ffffc90000541000 R12: 0000000000000000 [ 2.472635] R13: ffff888014951d90 R14: 0000000000000000 R15: ffff888014950000 [ 2.472635] FS: 00007fe597ad8180(0000) GS:ffff88806fc00000(0000) knlGS:0000000000000000 [ 2.472635] CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 [ 2.472635] CR2: ffffc90000548480 CR3: 0000000016444000 CR4: 00000000000006b0 [ 2.472635] Kernel panic - not syncing: Fatal exception [ 2.472635] Kernel Offset: disabled [ 2.472635] ---[ end Kernel panic - not syncing: Fatal exception ]---

1 0

Pass Ethernet device to CAmkES ARM VM when using QEMU
by Olof Holmberg 03 Jun '21

03 Jun '21

Hi, I am currently trying to pass a device for ethernet access through qemu to the vm. However there seems to be some issue since the device is not passed through correctly. I have looked at some resources for guidance on how to solve it: https://github.com/seL4/sel4webserver (webserver example) https://lists.sel4.systems/hyperkitty/list/devel@sel4.systems/message/X34TX… (old devel thread) And the important parts for this to work seems to be untyped_mmios for the vm (in devices.camkes for qemu-arm-virt): vm0.untyped_mmios = [ "0x8040000:12", // Interrupt Controller Virtual CPU interface (Virtual Machine view) /* TODO: QEMU PCI addresses could change - ideally need to decode from pcie node */ "0x10040000:17", // QEMU PCI MMIO "0x3eff0000:16", // QEMU PCI IO ports "0x40000000:29", // Linux kernel memory regions ]; And passing the device to QEMU in the simulation script: $ sudo ./simulate --extra-qemu-args="-netdev tap,id=mynet0,ifname=tap0,script=no,downscript=no -device virtio-net,netdev=mynet0,mac=52:55:00:d1:55:01" However when listing the devices with "ip a" on the VM it does not show an eth0 device: # ip a 1: lo: <LOOPBACK,UP,LOWER_UP> mtu 65536 qdisc noqueue qlen 1 link/loopback 00:00:00:00:00:00 brd 00:00:00:00:00:00 inet 127.0.0.1/8 scope host lo valid_lft forever preferred_lft forever inet6 ::1/128 scope host valid_lft forever preferred_lft forever 2: tunl0@NONE: <NOARP> mtu 1480 qdisc noop qlen 1 link/ipip 0.0.0.0 brd 0.0.0.0 3: ip6tnl0@NONE: <NOARP> mtu 1452 qdisc noop qlen 1 link/tunnel6 00:00:00:00:00:00:00:00:00:00:00:00:00:00:00:00 brd 00:00:00:00:00:00:00:00:00:00:00:00:00:00:00:00 But on the host the device that is passed to qemu can be seen: $ ip link show tap0 6: tap0: <BROADCAST,MULTICAST> mtu 1500 qdisc noop state DOWN mode DEFAULT group default qlen 1000 link/ether 62:43:43:54:2d:e6 brd ff:ff:ff:ff:ff:ff I am not sure if I missed something or if it is the QEMU addresses for the pci region that are not correct. Is there any output during boot or build that could give insight in what went wrong when it tries to passthrough the device? Also are there are any resources or guidelines on how to decode the pcie node? (Since I assume this has to be done inside the vm with the limited selection of commands available). Best regards, Olof

1 1

Blocking and unblocking under the MCS kernel
by Robert Kaiser 02 Jun '21

02 Jun '21

Hi all, I'm working on the SOS example of the AOS course, trying to adapt code that used to work under the non-MCS kernel to the now used MCS kernel. So far, this mostly works. However, I'm having problems in resuming a thread that is blocked in an IPC Call operation. In simple cases where the server can reply immediately, the thread is successfully unblocked, simply by replying to the reply object as with the reply capability in the non-MCS kernel. However, if the server does not respond immediately, (i.e. it leaves the calling thread in blocked state, serves some other requests and/or notifications in the meantime, then comes back to reply), replying to the reply object silently fails to unblock the thread for some reason. In the non-MCS kernel, it was necessary in these cases to save the reply capability in a cspace. Therefore I tried to similarly copy/move the reply object to a thread-specific cspace slot, but that doesn't help. I'm sure I'm missing something very basic here. Can anybody point me to the right direction? Best, Robert -- Robert Kaiser Technische Informatik Hochschule RheinMain Wiesbaden Rüsselsheim Computer Engineering RheinMain University of Applied Sciences robert.kaiser(a)hs-rm.de http://www.cs.hs-rm.de/~kaiser tel:(+49)611-9495-1292 fax:(+49)611-9495-1210 Postal Address: Robert Kaiser, Hochschule RheinMain, FB DCSM/Informatik Unter den Eichen 5, 65195 Wiesbaden, Germany

2 2

Easy way to edit VM guest file system
by skydivebcn＠gmail.com 02 Jun '21

02 Jun '21

Hi, I'm learning about this project: https://github.com/seL4/sel4webserver and would like to edit the guest filesystem. Digging around I found some cpio files that looks to me like may be the right place (output_overlay_rootfs.cpio, rootfs.cpio) but I'm not sure. So, as far I understand in theory I can just edit them and the execute "ninja" again. Before going that way, can anyone confirm this is the easiest/right way? Thanks,

3 2

CAmkES Tutorial, check_deps.py - what does good look like?
by Roderick Chapman 02 Jun '21

02 Jun '21

The first CAmkES tutorial points me at the "Usage" section of the CAmkES manual, which tells me to run "./tools/check_deps.py" to see if I have "the appropriate dependencies installed" but I have no idea what that means... What does good look like? I assume I'm supposed to run that from within the Docker container? If I do that, I get the output below, but I have no idea if that's right. I would expect the Docker container to "Pass" this test with flying colours... so I think I might have screwed up somewhere... Can anyone advise please? Thanks, Rod --- rchapman@in-container:/host/sel4-tutorials-manifest/projects/camkes-tool$ tools/check_deps.py Dependencies of CAmkES runner jinja2 (Python templating module)... Not found plyplus (Python parsing module)... Not found ply (Python parsing module)... Not found elftools (Python ELF parsing module)... Not found orderedset (Python OrderedSet module (orderedset))... Not found six (Python 2/3 compatibility layer)... Found sqlite3 (Python SQLite module)... Found pyfdt (Python flattened device tree parser)... Not found You will not be able to build/run this component Dependencies of CAmkES test suite expect (automation utility)... Found pylint (Python linter)... Found qemu-system-arm (ARM emulator)... Found qemu-system-i386 (IA32 emulator)... Found pycparser (Python C parsing module)... Not found gcc (C compiler)... Found spin (model checker)... Found sha256sum (file hashing utility)... Found You will not be able to build/run this component Dependencies of CapDL translator stack (Haskell version manager)... Found Dependencies of seL4 gcc (C compiler)... Found tempita (Python templating module)... Not found xmllint (XML validator)... Found bash (shell)... Found make (GNU Make build tool)... Found cpio (CPIO file system tool)... Found You will not be able to build/run this component Suggestions: c-parser (NICTA C-to-Simpl parser): you will need this installed if you want to validate code for verification clang-format (Clang code reformatter): installing this will reflow generated C code to make it more readable VBoxManage (VirtualBox administration tool): you will need this installed if you want to build VMWare images mformat (formatting tool for MSDOS disks): you will need this installed if you want to build QEMU images for IA32 figleaf (code coverage tool for Python): you will need this installed if you want to measure code coverage within CAmkES python-coverage (code coverage tool for Python): you will need this installed if you want to measure code coverage within CAmkES syslinux (Linux bootloader tool): you will need this installed if you want to build QEMU images for IA32 mpartition (partitioning tool for MSDOS disks): you will need this installed if you want to build QEMU images for IA32 pandoc (document format translator): you will need this if you want to build the CAmkES documentation mcopy (copying tool for MSDOS disks): you will need this installed if you want to build QEMU images for IA32 sponge (input coalescer from moreutils): installing this will give a marginal improvement in compilation times

2 1

Running ninja twice fails in https://github.com/seL4/sel4webserver
by skydivebcn＠gmail.com 02 Jun '21

02 Jun '21

Hi, I have noticed I'm never unable to run "ninja" for a second time and I'm required to rm -rf all the contents of "build" directory, and run "../init-build.sh" again before running ninja again. If I try to simpley run "ninja" twice the error I get is: (...) /var/lib/gems/2.7.0/gems/jekyll-4.0.0/lib/jekyll/tags/include.rb:179: warning: Using the last argument as keyword parameters is deprecated /var/lib/gems/2.7.0/gems/jekyll-4.0.0/lib/jekyll/tags/include.rb:179: warning: Using the last argument as keyword parameters is deprecated (many times...) /var/lib/gems/2.7.0/gems/jekyll-4.0.0/lib/jekyll/tags/include.rb:179: warning: Using the last argument as keyword parameters is deprecated /home/hugo/seL4/sel4webserver/build/docsite-prefix/src/docsite/_plugins/include_absolute.rb:71: warning: Using the last argument as keyword parameters is deprecated done in 10.04 seconds. Auto-regeneration: disabled. Use --watch to enable. ninja: build stopped: subcommand failed. Any hint on what could be happening? Anyone else having same issue? I'm doing something wrong?

1 0