Hello all, I am running camkes-vm on x86 architecture, following the example on wiki https://wiki.sel4.systems/CAmkESVM#Cross_VM_Connectors with the exception that I want to invoke the stringReverse component https://github.com/podhrmic/camkes-vm/tree/master/components/StringReverse . I am running the optiplex9020_defconfig example with only one VM, and when I start booting the guest linux system, I see the following error: *[ 1.282326] dataport: loading out-of-tree module taints kernel.* *[ 1.290615] dataport: module license 'unspecified' taints kernel.* *[ 1.306854] Disabling lock debugging due to kernel taint* *[ 1.319664] dataport initialized with major number 247* *vmm_vmcall_handler:55 | Failed to find handler for token:2* *[ 1.325411] incorrect event context magic number (expected 42, got -677408512)insmod: can't insert '/lib/modules/4.8.16/kernel/drivers/vmm/consumes_event.ko': Operation not ermitted* *[ 1.337441] emits_event initialized with major number 245* *[ 1.356391] k_vmm_manager: failed on sel4 hypervisor connection |-1|* Then when I log into linux and call `string_reverse https://github.com/podhrmic/camkes-vm/tree/master/linux/pkg/string_reverse` program, I get the following error: *# string_reverse * *[ 8.360164] BUG: unable to handle kernel paging request at d881f2c0* *[ 8.360164] IP: [<d00a69f0>] chrdev_open+0xab/0x100* *[ 8.360164] *pde = 17867067 *pte = 00000000 * *[ 8.360164] Oops: 0000 [#1]* *[ 8.360164] Modules linked in: emits_event(PO) dataport(PO)* *[ 8.360164] CPU: 0 PID: 691 Comm: string_reverse Tainted: P O 4.8.16 #1* *[ 8.360164] task: d79c9740 task.stack: d6ae0000* *[ 8.360164] EIP: 0060:[<d00a69f0>] EFLAGS: 00010286 CPU: 0* *[ 8.360164] EIP is at chrdev_open+0xab/0x100* *[ 8.360164] EAX: d881f2c0 EBX: 00000000 ECX: d79b0d00 EDX: 00000000* *[ 8.360164] ESI: d79b0d00 EDI: d6add808 EBP: d6ae1e10 ESP: d6ae1df8* *[ 8.360164] DS: 007b ES: 007b FS: 0000 GS: 0033 SS: 0068* *[ 8.360164] CR0: 80050033 CR2: d881f2c0 CR3: 16ad9000 CR4: 00102690* *[ 8.360164] DR0: 00000000 DR1: 00000000 DR2: 00000000 DR3: 00000000* *[ 8.360164] DR6: fffe0ff0 DR7: 00000400* *[ 8.360164] Stack:* *[ 8.360164] d7ac9be0 d7ac9be0 00000001 d7ac9be0 d6add808 00000000 d6ae1e30 d00a2370* *[ 8.360164] d6ae1e28 d7ac9be8 d00a6945 d7ac9be0 d69db010 d7462d80 d6ae1e4c d00a2cf8* *[ 8.360164] d79c2b80 d79c2b80 00000000 d6ae1ebc d7462d80 d6ae1eb0 d00ae159 d6ae1e64* *[ 8.360164] Call Trace:* *[ 8.360164] [<d00a2370>] do_dentry_open+0x197/0x216* *[ 8.360164] [<d00a6945>] ? cdev_put+0x1a/0x1a* *[ 8.360164] [<d00a2cf8>] vfs_open+0x45/0x4e* *[ 8.360164] [<d00ae159>] path_openat+0x822/0x970* *[ 8.360164] [<d007a468>] ? __alloc_pages_nodemask+0x11c/0x770* *[ 8.360164] [<d00ae2d8>] do_filp_open+0x31/0x77* *[ 8.360164] [<d00b6293>] ? __alloc_fd+0xbb/0xfe* *[ 8.360164] [<d00a2e56>] do_sys_open+0x54/0xc7* *[ 8.360164] [<d00a2ee1>] SyS_open+0x18/0x1a* *[ 8.360164] [<d0000ee1>] do_fast_syscall_32+0x7a/0xb8* *[ 8.360164] [<d047831f>] sysenter_past_esp+0x40/0x6a* *[ 8.360164] Code: 11 89 f0 e8 e1 fa ff ff 83 f8 01 19 db 31 d2 83 e3 fa 89 d0 e8 4d ff ff ff 85 db 75 59 8b 46 28 85 c0 75 0c* *[ 8.360164] EIP: [<d00a69f0>] chrdev_open+0xab/0x100 SS:ESP 0068:d6ae1df8* *[ 8.360164] CR2: 00000000d881f2c0* *[ 8.360164] ---[ end trace 46873a57a343e435 ]---* *[ 8.376285] string_reverse (691) used greatest stack depth: 6496 bytes left* *Killed* which seems like the program is trying to access memory that it is not supposed to. If I follow the example from wiki (here https://wiki.sel4. systems/CAmkESVM#Cross_VM_Connectors ) I get the same error, but triggered by `print_client` program. Have you seen a problem like this before? How do I correctly load the kernel module? Regards Michal