Javier Martinez Canillas
0d6d0d62d9
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: Hans de Goede <hdegoede@redhat.com>
Signed-off-by: Javier Martinez Canillas <javierm@redhat.com>
Reviewed-by: Jarkko Sakkinen <jarkko.sakkinen@linux.intel.com>
Signed-off-by: Jarkko Sakkinen <jarkko.sakkinen@linux.intel.com>
Linux kernel
============
There are several guides for kernel developers and users. These guides can
be rendered in a number of formats, like HTML and PDF. Please read
Documentation/admin-guide/README.rst first.
In order to build the documentation, use ``make htmldocs`` or
``make pdfdocs``. The formatted documentation can also be read online at:
https://www.kernel.org/doc/html/latest/
There are various text files in the Documentation/ subdirectory,
several of them using the Restructured Text markup notation.
See Documentation/00-INDEX for a list of what is contained in each file.
Please read the Documentation/process/changes.rst file, as it contains the
requirements for building and running the kernel, and information about
the problems which may result by upgrading your kernel.