On Fri, Nov 16, 2018 at 3:37 PM Vitaly Kuznetsov vkuznets@redhat.com wrote:
Ahmed Soliman ahmedsoliman@mena.vt.edu writes:
Hello once again,
I noticed that there is still more problems with kvmself test (at least on my machine)
Any test that would successfully reach the guest's code immediately VMexit by a shutdown.
$ ./vmx_tsc_adjust_test ==== Test Assertion Failure ==== x86_64/vmx_tsc_adjust_test.c:156: run->exit_reason == KVM_EXIT_IO pid=8499 tid=8499 - Success 1 0x00005604f07bd36c: ?? ??:0 2 0x00007f5c0dc53ae6: ?? ??:0 3 0x00005604f07bd4b9: ?? ??:0 Got exit_reason other than KVM_EXIT_IO: 8 (SHUTDOWN)
Hm, this is weird. Do other KVM users, e.g. qemu work on this host? Are you sure this happens on the first VCPU_RUN invocation?
Yes and I have just tested: qemu-system-x86_64 -enable-kvm -cpu host,+vmx -m 2G
And Linux as well as android for x86 booted up. Also I kinda have my kvm tests that works but they are not built on top of kvm selftest api.
Could you try doing
trace-cmd record -e kvm ./x86_64/vmx_tsc_adjust_test && trace-cmd report
to see if there's anything suspicious?
Yes, there is a triple fault induced shutdown probably during EPT handling:
vmx_tsc_adjust_-17638 [001] 15628.729863: kvm_update_master_clock: masterclock 0 hostclock tsc offsetmatched 0 vmx_tsc_adjust_-17638 [001] 15628.730820: kvm_write_tsc_offset: vcpu=5 prev=0 next=18446733817569215369 vmx_tsc_adjust_-17638 [001] 15628.730822: kvm_track_tsc: vcpu_id 5 masterclock 0 offsetmatched 0 nr_online 1 hostclock tsc vmx_tsc_adjust_-17638 [001] 15628.730911: kvm_fpu: load vmx_tsc_adjust_-17638 [001] 15628.730913: kvm_update_master_clock: masterclock 1 hostclock tsc offsetmatched 1 vmx_tsc_adjust_-17638 [001] 15628.730954: kvm_entry: vcpu 5 vmx_tsc_adjust_-17638 [001] 15628.730974: kvm_exit: reason EPT_VIOLATION rip 0x56545f0b8760 info 83 0 vmx_tsc_adjust_-17638 [001] 15628.730976: kvm_page_fault: address 180560 error_code 83 vmx_tsc_adjust_-17638 [001] 15628.730989: kvm_entry: vcpu 5 vmx_tsc_adjust_-17638 [001] 15628.730992: kvm_exit: reason TRIPLE_FAULT rip 0x56545f0b8760 info 0 0 vmx_tsc_adjust_-17638 [001] 15628.730993: kvm_fpu: unload vmx_tsc_adjust_-17638 [001] 15628.730996: kvm_userspace_exit: reason KVM_EXIT_SHUTDOWN (8) vmx_tsc_adjust_-17638 [002] 15628.739237: kvm_hv_stimer_cleanup: vcpu_id 5 timer 0 vmx_tsc_adjust_-17638 [002] 15628.739244: kvm_hv_stimer_cleanup: vcpu_id 5 timer 1 vmx_tsc_adjust_-17638 [002] 15628.739244: kvm_hv_stimer_cleanup: vcpu_id 5 timer 2 vmx_tsc_adjust_-17638 [002] 15628.739245: kvm_hv_stimer_cleanup: vcpu_id 5 timer 3
I will try to dive into them after my midterms are over(ends tomorrow) but I would need to verify that someone else can reproduce this, I tried bisecting but it seams that this bug was there from kvmselftests commit one (rebuilt kernel, kvm and the kvm selftests each time).
Thanks,