Re: kvm_buf_set_msrs: Assertion `ret == cpu->kvm_msr_buf->nmsrs' failed.

[Paolo Bonzini]

On 20/05/20 05:50, Li Feng wrote:
>>>>>>>>> qemu-system-x86_64: error: failed to set MSR 0x48f to 0x7fefff00036dfb

The high 32 bits are 0111 1111 1110 1111 1111 1111.

The low 32 bits are  0000 0011 0110 1101 1111 1011.

The features that are set are the xor, so 0111 1100 1000 0010 0000 0100:

- bit 2, vmx-exit-nosave-debugctl
- bit 9, host address space size, is handled automatically by QEMU
- bit 15, vmx-exit-ack-intr
- bit 17, vmx-exit-save-pat
- bit 18, vmx-exit-load-pat
- bit 19, vmx-exit-save-efer
- bit 20, vmx-exit-load-efer
- bit 21, vmx-exit-save-preemption-timer

Try removing all of these and see if QEMU starts:

qemu-kvm ... -cpu
host,-vmx-exit-nosave-debugctl,-vmx-exit-ack-intr,-vmx-exit-save-pat,-vmx-exit-load-pat,-vmx-exit-save-efer,-vmx-exit-load-efer,-vmx-exit-save-preemption-timer

And then add them back one at a time.

Paolo