diff options
| author | Stefan Berger <stefanb@linux.ibm.com> | 2021-08-12 22:45:48 +0300 |
|---|---|---|
| committer | Jarkko Sakkinen <jarkko@kernel.org> | 2021-08-23 19:55:42 +0300 |
| commit | 047d4226b0bca1cda5267dc68bc8291cce5364ac (patch) | |
| tree | c1464a083ec941aa301f422fd4545e389d9a2445 /drivers/char/tpm/tpm_ibmvtpm.h | |
| parent | a4aed36ed5924a05ecfadc470584188bfba2b928 (diff) | |
| download | linux-047d4226b0bca1cda5267dc68bc8291cce5364ac.tar.xz | |
tpm: ibmvtpm: Avoid error message when process gets signal while waiting
When rngd is run as root then lots of these types of message will appear
in the kernel log if the TPM has been configured to provide random bytes:
[ 7406.275163] tpm tpm0: tpm_transmit: tpm_recv: error -4
The issue is caused by the following call that is interrupted while
waiting for the TPM's response.
sig = wait_event_interruptible(ibmvtpm->wq, !ibmvtpm->tpm_processing_cmd);
Rather than waiting for the response in the low level driver, have it use
the polling loop in tpm_try_transmit() that uses a command's duration to
poll until a result has been returned by the TPM, thus ending when the
timeout has occurred but not responding to signals and ctrl-c anymore. To
stay in this polling loop extend tpm_ibmvtpm_status() to return
'true' for as long as the vTPM is indicated as being busy in
tpm_processing_cmd. Since the loop requires the TPM's timeouts, get them
now using tpm_get_timeouts() after setting the TPM2 version flag on the
chip.
To recreat the resolved issue start rngd like this:
sudo rngd -r /dev/hwrng -t
sudo rngd -r /dev/tpm0 -t
Link: https://bugzilla.redhat.com/show_bug.cgi?id=1981473
Fixes: 6674ff145eef ("tpm_ibmvtpm: properly handle interrupted packet receptions")
Cc: Nayna Jain <nayna@linux.ibm.com>
Cc: George Wilson <gcwilson@linux.ibm.com>
Reported-by: Nageswara R Sastry <rnsastry@linux.ibm.com>
Signed-off-by: Stefan Berger <stefanb@linux.ibm.com>
Tested-by: Nageswara R Sastry <rnsastry@linux.ibm.com>
Reviewed-by: Jarkko Sakkinen <jarkko@kernel.org>
Signed-off-by: Jarkko Sakkinen <jarkko@kernel.org>
Diffstat (limited to 'drivers/char/tpm/tpm_ibmvtpm.h')
| -rw-r--r-- | drivers/char/tpm/tpm_ibmvtpm.h | 2 |
1 files changed, 1 insertions, 1 deletions
diff --git a/drivers/char/tpm/tpm_ibmvtpm.h b/drivers/char/tpm/tpm_ibmvtpm.h index b92aa7d3e93e..51198b137461 100644 --- a/drivers/char/tpm/tpm_ibmvtpm.h +++ b/drivers/char/tpm/tpm_ibmvtpm.h @@ -41,7 +41,7 @@ struct ibmvtpm_dev { wait_queue_head_t wq; u16 res_len; u32 vtpm_version; - bool tpm_processing_cmd; + u8 tpm_processing_cmd; }; #define CRQ_RES_BUF_SIZE PAGE_SIZE |