4.14-stable review patch. If anyone has any objections, please let me know.
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[ 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 | 3 ++- 1 file changed, 2 insertions(+), 1 deletion(-)
diff --git a/drivers/char/tpm/tpm-interface.c b/drivers/char/tpm/tpm-interface.c index a2070ab86c82..89d5915b1a3f 100644 --- a/drivers/char/tpm/tpm-interface.c +++ b/drivers/char/tpm/tpm-interface.c @@ -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;