• Javier Martinez Canillas's avatar
    tpm: suppress transmit cmd error logs when TPM 1.2 is disabled/deactivated · 0d6d0d62
    Javier Martinez Canillas authored
    For TPM 1.2 chips the system setup utility allows to set the TPM device in
    one of the following states:
    
      * Active: Security chip is functional
      * Inactive: Security chip is visible, but is not functional
      * Disabled: Security chip is hidden and is not functional
    
    When choosing the "Inactive" state, the TPM 1.2 device is enumerated and
    registered, but sending TPM commands fail with either TPM_DEACTIVATED or
    TPM_DISABLED depending if the firmware deactivated or disabled the TPM.
    
    Since these TPM 1.2 error codes don't have special treatment, inactivating
    the TPM leads to a very noisy kernel log buffer that shows messages like
    the following:
    
      tpm_tis 00:05: 1.2 TPM (device-id 0x0, rev-id 78)
      tpm tpm0: A TPM error (6) occurred attempting to read a pcr value
      tpm tpm0: TPM is disabled/deactivated (0x6)
      tpm tpm0: A TPM error (6) occurred attempting get random
      tpm tpm0: A TPM error (6) occurred attempting to read a pcr value
      ima: No TPM chip found, activating TPM-bypass! (rc=6)
      tpm tpm0: A TPM error (6) occurred attempting get random
      tpm tpm0: A TPM error (6) occurred attempting get random
      tpm tpm0: A TPM error (6) occurred attempting get random
      tpm tpm0: A TPM error (6) occurred attempting get random
    
    Let's just suppress error log messages for the TPM_{DEACTIVATED,DISABLED}
    return codes, since this is expected when the TPM 1.2 is set to Inactive.
    
    In that case the kernel log is cleaner and less confusing for users, i.e:
    
      tpm_tis 00:05: 1.2 TPM (device-id 0x0, rev-id 78)
      tpm tpm0: TPM is disabled/deactivated (0x6)
      ima: No TPM chip found, activating TPM-bypass! (rc=6)
    Reported-by: default avatarHans de Goede <hdegoede@redhat.com>
    Signed-off-by: default avatarJavier Martinez Canillas <javierm@redhat.com>
    Reviewed-by: default avatarJarkko Sakkinen <jarkko.sakkinen@linux.intel.com>
    Signed-off-by: default avatarJarkko Sakkinen <jarkko.sakkinen@linux.intel.com>
    0d6d0d62
tpm-interface.c 33.9 KB