Hi, I just compiled ovmf, updated to commit 6612ff8 (24/12/2021): https://github.com/tianocore/edk2/commit/6612ff85611bc2be16dc0fd5de0e1413df88941a The build command: build -a X64 -b RELEASE -D SECURE_BOOT_ENABLE -D TPM_ENABLE -D FD_SIZE_4MB -p OvmfPkg/OvmfPkgX64.dsc -t GCC5 And used OVMF_CODE.fd and OVMF_VARS.fd for my windows 11 vm in qemu. Looking at system devices, Windows 11 now can't start TPM 2.0 device (Error code 10). I also tried to uninstall tpm and reinstall, same issue. Switching back to 202108 stable version and no issue. I can try to bisect to find the commit causing the issue, but maybe you are faster in finding what broke it.