I have tried and failed to run xen on 3 -current/amd64 systems with 3 different failure modes:
1) laptop: xen.gz Building a PV Dom0 / ELF: not an ELF binary -> panic/reboot 2) desktop: XEN3_DOM0 panics including PR port-xen/55978 3) server: Trampoline space cannot be allocated; will try fallback -> reboot They are all working NetBSD-current/amd64 systems. My conclusion was that xen is hopelessly broken, so was quite surprised by Greg Wood's thread about the finer points of running a guest OS, given that those systems won't even start the host OS. I dug out an old desktop, and to my pleasant surprise it booted XEN3_DOM0, and I have managed to run some XEN3_DOMUs. The difference between the working/broken setups seems to be that the working one is "BIOS" booting rather than EFI booting. Among all your xen success stories, are any of you EFI booting? Cheers, Patrick ========================================================================= Some extra gory details 1) laptop: **** Building a PV Dom0 **** ELF: Not an ELF binary *********************************** Panic on CPU 0: Could not set up DOM0 guest OS *********************************** Reboot in five seconds... 2) desktop: selection of panics in addition to PR port-xen/55978 [ 80.9899999] panic: LIST_INSERT_HEAD 0xffffa080073eec28 ../../../../arch/x86/x86/pmap.c:2285 [ 80.9899999] cpu13: Begin traceback... [ 80.9899999] vpanic() at netbsd:vpanic+0x14a [ 80.9899999] snprintf() at netbsd:snprintf [ 80.9899999] pmap_enter_ma() at netbsd:pmap_enter_ma+0x14e7 [ 80.9899999] pmap_enter() at netbsd:pmap_enter+0x32 [ 80.9899999] udv_fault() at netbsd:udv_fault+0x100 [ 80.9899999] uvm_fault_internal() at netbsd:uvm_fault_internal+0x574 [ 80.9899999] trap() at netbsd:trap+0x432 [ 80.9899999] --- trap (number 6) --- [ 80.9899999] 7a60617787af: [ 80.9899999] cpu13: End traceback... [ 75.6599981] panic: kernel diagnostic assertion "ncp->nc_dvp == dvp" failed: file "../../../../kern/vfs_cache.c", line 432 [ 75.6599981] cpu0: Begin traceback... [ 75.6599981] vpanic() at netbsd:vpanic+0x14a [ 75.6599981] kern_assert() at netbsd:kern_assert+0x48 [ 75.6599981] cache_lookup_entry() at netbsd:cache_lookup_entry+0xde [ 75.6599981] cache_lookup_linked() at netbsd:cache_lookup_linked+0x160 [ 75.6599981] namei_tryemulroot() at netbsd:namei_tryemulroot+0x298 [ 75.6599981] namei() at netbsd:namei+0x29 [ 75.6599981] vn_open() at netbsd:vn_open+0x8f [ 75.6599981] do_open() at netbsd:do_open+0x119 [ 75.6599981] do_sys_openat() at netbsd:do_sys_openat+0x74 [ 75.6599981] sys_open() at netbsd:sys_open+0x24 [ 75.6599981] syscall() at netbsd:syscall+0x9c [ 75.6599981] --- syscall (number 5) --- [ 75.6599981] netbsd:syscall+0x9c: [ 75.6599981] cpu0: End traceback... 3) server: EFI boot of Feb 6 2021, xenkernel413-4.13.3.tgz, serial console On serial console, all that is seen is: 2415648+1324000=0x3910ec Loading /var/db/entropy-file Loading /netbsd-XEN3_DOM0 Start @ 0xce600000 [1=0xce991000-0xce9910ec]... Trampoline space cannot be allocated; will try fallback. then it reboots
