In case swtpm was to return a control channel message with an error code it
would only return 4 bytes. However, some of the commands expect a response
with more bytes and QEMU would get stuck in qemu_chr_fe_read_all() waiting
for bytes following the error code. Therefore, read the response in 2
passes stopping if an error code is received in the first 4 bytes to avoid
getting stuck.

   Stefan

Stefan Berger (2):
  tpm: Use new ptm_cap_n structure for PTM_GET_CAPABILITY
  tpm_emulator: Read control channel response in 2 passes

 backends/tpm/tpm_emulator.c | 39 +++++++++++++++++++++++++++++--------
 backends/tpm/tpm_ioctl.h    | 13 ++++++++++++-
 backends/tpm/trace-events   |  2 +-
 3 files changed, 44 insertions(+), 10 deletions(-)

-- 
2.46.2