TPM: Long default timeout fix

If duration variable value is 0 at this point, it's because
chip->vendor.duration wasn't filled by tpm_get_timeouts() yet.
This patch sets then the lowest timeout just to give enough
time for tpm_get_timeouts() to further succeed.

This fix avoids long boot times in case another entity attempts
to send commands to the TPM when the TPM isn't accessible.

Signed-off-by: Rajiv Andrade <srajiv@linux.vnet.ibm.com>
Signed-off-by: James Morris <jmorris@namei.org>

1 files changed, 6 insertions, 4 deletions

diff --git a/drivers/char/tpm/tpm.c b/drivers/char/tpm/tpm.c
index 1f46f1cd9225..36e0fa161c2b 100644
--- a/drivers/char/tpm/tpm.c
+++ b/drivers/char/tpm/tpm.c
@@ -364,12 +364,14 @@ unsigned long tpm_calc_ordinal_duration(struct tpm_chip *chip,
                     tpm_protected_ordinal_duration[ordinal &
                                                    TPM_PROTECTED_ORDINAL_MASK];
 
-        if (duration_idx != TPM_UNDEFINED)
+        if (duration_idx != TPM_UNDEFINED) {
                 duration = chip->vendor.duration[duration_idx];
-        if (duration <= 0)
+                /* if duration is 0, it's because chip->vendor.duration wasn't */
+                /* filled yet, so we set the lowest timeout just to give enough */
+                /* time for tpm_get_timeouts() to succeed */
+                return (duration <= 0 ? HZ : duration);
+        } else
                 return 2 * 60 * HZ;
-        else
-                return duration;
 }
 EXPORT_SYMBOL_GPL(tpm_calc_ordinal_duration);