]> git.hungrycats.org Git - linux/commitdiff
tpm: move the delay_msec increment after sleep in tpm_transmit()
authorNayna Jain <nayna@linux.vnet.ibm.com>
Mon, 2 Apr 2018 16:20:06 +0000 (21:50 +0530)
committerGreg Kroah-Hartman <gregkh@linuxfoundation.org>
Sun, 4 Nov 2018 13:52:44 +0000 (14:52 +0100)
[ Upstream commit 92980756979a9c51be0275f395f4e89c42cf199a ]

Commit e2fb992d82c6 ("tpm: add retry logic") introduced a new loop to
handle the TPM2_RC_RETRY error. The loop retries the command after
sleeping for the specified time, which is incremented exponentially in
every iteration.

Unfortunately, the loop doubles the time before sleeping, causing the
initial sleep to be doubled. This patch fixes the initial sleep time.

Fixes: commit e2fb992d82c6 ("tpm: add retry logic")
Signed-off-by: Nayna Jain <nayna@linux.vnet.ibm.com>
Reviewed-by: Mimi Zohar <zohar@linux.vnet.ibm.com>
Tested-by: Jarkko Sakkinen <jarkko.sakkinen@linux.intel.com>
Reviewed-by: Jarkko Sakkinen <jarkko.sakkinen@linux.intel.com>
Signed-off-by: Jarkko Sakkinen <jarkko.sakkinen@linux.intel.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
drivers/char/tpm/tpm-interface.c

index a2070ab86c824c402d142395f19389e578e205c3..89d5915b1a3fccf165fe9e41d3149a47f8b9c31e 100644 (file)
@@ -611,12 +611,13 @@ ssize_t tpm_transmit(struct tpm_chip *chip, struct tpm_space *space,
                rc = be32_to_cpu(header->return_code);
                if (rc != TPM2_RC_RETRY)
                        break;
-               delay_msec *= 2;
+
                if (delay_msec > TPM2_DURATION_LONG) {
                        dev_err(&chip->dev, "TPM is in retry loop\n");
                        break;
                }
                tpm_msleep(delay_msec);
+               delay_msec *= 2;
                memcpy(buf, save, save_size);
        }
        return ret;