With some Infineon chips the timeouts in tpm_tis_send_data (both B and
C) can reach up to about 2250 ms.
Timeout C is retried since
commit de9e33df7762 ("tpm, tpm_tis: Workaround failed command reception on
Infineon devices")
Timeout B still needs to be extended.
The problem is most commonly encountered with context related operation
such as load context/save context. These are issued directly by the
kernel, and there is no retry logic for them.
When a filesystem is set up to use the TPM for unlocking the boot fails,
and restarting the userspace service is ineffective. This is likely
because ignoring a load context/save context result puts the real TPM
state and the TPM state expected by the kernel out of sync.
Chips known to be affected:
tpm_tis IFX1522:00: 2.0 TPM (device-id 0x1D, rev-id 54)
Description: SLB9672
Firmware Revision: 15.22
tpm_tis MSFT0101:00: 2.0 TPM (device-id 0x1B, rev-id 22)
Firmware Revision: 7.83
tpm_tis MSFT0101:00: 2.0 TPM (device-id 0x1A, rev-id 16)
Firmware Revision: 5.63
Link: https://lore.kernel.org/linux-integrity/z5pi07m0muapy...@kitsune.suse.cz/
Signed-off-by: Michal Suchanek <msucha...@suse.de>
---
v2: Only extend timeout B
v3: Update commit message
---
drivers/char/tpm/tpm_tis_core.h | 2 +-
include/linux/tpm.h | 2 +-
2 files changed, 2 insertions(+), 2 deletions(-)
diff --git a/drivers/char/tpm/tpm_tis_core.h b/drivers/char/tpm/tpm_tis_core.h
index 970d02c337c7..6c3aa480396b 100644
--- a/drivers/char/tpm/tpm_tis_core.h
+++ b/drivers/char/tpm/tpm_tis_core.h
@@ -54,7 +54,7 @@ enum tis_int_flags {
enum tis_defaults {
TIS_MEM_LEN = 0x5000,
TIS_SHORT_TIMEOUT = 750, /* ms */
- TIS_LONG_TIMEOUT = 2000, /* 2 sec */
+ TIS_LONG_TIMEOUT = 4000, /* 4 secs */
TIS_TIMEOUT_MIN_ATML = 14700, /* usecs */
TIS_TIMEOUT_MAX_ATML = 15000, /* usecs */
};
diff --git a/include/linux/tpm.h b/include/linux/tpm.h
index 6c3125300c00..3db0b6a87d45 100644
--- a/include/linux/tpm.h
+++ b/include/linux/tpm.h
@@ -224,7 +224,7 @@ enum tpm2_const {
enum tpm2_timeouts {
TPM2_TIMEOUT_A = 750,
- TPM2_TIMEOUT_B = 2000,
+ TPM2_TIMEOUT_B = 4000,
TPM2_TIMEOUT_C = 200,
TPM2_TIMEOUT_D = 30,
TPM2_DURATION_SHORT = 20,
--
2.47.1
