Cannot find /dev/tpm0 in the guest

[itsucks]

Hi, I've integrate swtpm and qemu-tpm in to nova-compute on devstack.
First, I create TPM_PATH and vtpm0 manually

# mkdir /tmp/vtpm0
# chown -R tss:root  /tmp/vtpm0
# swtpm_setup --tpm-state /tmp/vtpm0  --createek 
# swtpm_cuse --name vtpm0 --tpmstate dir=/tmp/vtpm0 --log file=/root/out.log

Then, I start the instance, the qemu comand is

/usr/bin/qemu-system-x86_64 -name instance-00000018 -S -machine pc-i440fx-2.4,accel=kvm,usb=off -bios /home/trust/seabios-tpm/out/bios.bin -m 1024 -realtime mlock=off -smp 2,sockets=2,cores=1,threads=1 -uuid c05f8b6d-f060-4f01-a91f-4c81b3a464b1 -smbios type=1,manufacturer=OpenStack Foundation,product=OpenStack Nova,version=13.1.3,serial=564d145f-6c15-1879-1d25-ca25bdf7a512,uuid=c05f8b6d-f060-4f01-a91f-4c81b3a464b1,family=Virtual Machine -no-user-config -nodefaults -chardev socket,id=charmonitor,path=/var/lib/libvirt/qemu/instance-00000018.monitor,server,nowait -mon chardev=charmonitor,id=monitor,mode=control -rtc base=utc,driftfix=slew -global kvm-pit.lost_tick_policy=discard -no-hpet -no-shutdown -boot strict=on -device piix3-usb-uhci,id=usb,bus=pci.0,addr=0x1.0x2 -drive file=/opt/stack/data/nova/instances/c05f8b6d-f060-4f01-a91f-4c81b3a464b1/disk,if=none,id=drive-virtio-disk0,format=qcow2,cache=none -device virtio-blk-pci,scsi=off,bus=pci.0,addr=0x4,drive=drive-virtio-disk0,id=virtio-disk0,bootindex=1 -drive file=/opt/stack/data/nova/instances/c05f8b6d-f060-4f01-a91f-4c81b3a464b1/disk.config,if=none,id=drive-ide0-1-1,readonly=on,format=raw,cache=none -device ide-cd,bus=ide.1,unit=1,drive=drive-ide0-1-1,id=ide0-1-1 -netdev tap,fd=24,id=hostnet0,vhost=on,vhostfd=25 -device virtio-net-pci,netdev=hostnet0,id=net0,mac=fa:16:3e:16:f5:0c,bus=pci.0,addr=0x3 -chardev file,id=charserial0,path=/opt/stack/data/nova/instances/c05f8b6d-f060-4f01-a91f-4c81b3a464b1/console.log -device isa-serial,chardev=charserial0,id=serial0 -chardev pty,id=charserial1 -device isa-serial,chardev=charserial1,id=serial1 -chardev socket,id=charserial2,path=/tmp/virtualsocket/c05f8b6d-f060-4f01-a91f-4c81b3a464b1,server,nowait -device isa-serial,chardev=charserial2,id=serial2 -vnc 192.168.1.238:0 -k en-us -device cirrus-vga,id=video0,bus=pci.0,addr=0x2 -device virtio-balloon-pci,id=balloon0,bus=pci.0,addr=0x5 -tpmdev cuse-tpm,id=tpm0,path=/dev/vtpm0 -device tpm-tis,tpmdev=tpm0

The vtpm log

CUSE TPM successfully initialized.
CUSE TPM successfully initialized.

But I can't find tpm0 in the guest...Do you guys have any suggestions on this please?
How did the qemu create /dev/tpm0 with “-tpmdev cuse-tpm,id=tpm0,path=/dev/vtpm0 -device tpm-tis,tpmdev=tpm0”?

[stefanberger]

Inside the guest run dmesg | grep -i tpm. Do you see any messages regarding TPM? What about lsmod | grep tpm. Does that show any loaded modules. What about modprobe tpm_tis or modprobe tpm_tis force=1. Does that make /dev/tpm0 appear?

[itsucks]

I ran these commands but got nothing.

ubuntu@vtpm:~$ dmesg | grep -i tpm
ubuntu@vtpm:~$ lsmod | grep tpm
ubuntu@vtpm:~$ modprobe tpm_tis
FATAL: Module tpm_tis not found.
ubuntu@vtpm:~$ modprobe tpm_tis force=1
FATAL: Module tpm_tis not found.

Does this mean that qemu failed to create tpm in the guest?

[stefanberger]

What about grep tpm_tis /proc/kallsyms ? It's odd that dmesg shows no TPM related output, not even that something related to TPM access failed.

[itsucks]

I tried 'grep tpm_tis /proc/kallsyms', got nothing./(ㄒoㄒ)/

[stefanberger]

Then your kernel has no TPM support.

[itsucks]

Thanks, that's point. I changed to another image and I found /dev/tpm0.