From: Javier Martinez Canillas Date: Thu, 30 Aug 2018 14:40:05 +0000 (+0200) Subject: tpm: suppress transmit cmd error logs when TPM 1.2 is disabled/deactivated X-Git-Tag: v4.20-rc1~119^2^2~4 X-Git-Url: https://asedeno.scripts.mit.edu/gitweb/?a=commitdiff_plain;h=0d6d0d62d9505a9816716aa484ebd0b04c795063;p=linux.git tpm: suppress transmit cmd error logs when TPM 1.2 is disabled/deactivated 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 Signed-off-by: Javier Martinez Canillas Reviewed-by: Jarkko Sakkinen Signed-off-by: Jarkko Sakkinen --- diff --git a/drivers/char/tpm/tpm-interface.c b/drivers/char/tpm/tpm-interface.c index 318a7078b2ba..7d958ff426e0 100644 --- a/drivers/char/tpm/tpm-interface.c +++ b/drivers/char/tpm/tpm-interface.c @@ -663,7 +663,8 @@ ssize_t tpm_transmit_cmd(struct tpm_chip *chip, struct tpm_space *space, return len; err = be32_to_cpu(header->return_code); - if (err != 0 && desc) + if (err != 0 && err != TPM_ERR_DISABLED && err != TPM_ERR_DEACTIVATED + && desc) dev_err(&chip->dev, "A TPM error (%d) occurred %s\n", err, desc); if (err)