Re: [PATCH] tpm: moves the delay_msec increment after sleep in tpm_transmit()

[Nayna Jain]

On 04/05/2018 03:42 PM, Jarkko Sakkinen wrote:
> On Mon, Apr 02, 2018 at 09:50:06PM +0530, Nayna Jain wrote:
> > 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. This patch fixes the initial sleep to be the default
> > sleep time.
> I think I understand the code change but do not understand what the
> long description.

It tells that the first sleep is delay_msec * 2 and not delay_msec.

> > Fixes: commit e2fb992d82c6 ("tpm: add retry logic")
> > Signed-off-by: Nayna Jain <nayna@xxxxxxxxxxxxxxxxxx>
> > Reviewed-by: Mimi Zohar <zohar@xxxxxxxxxxxxxxxxxx>
> > ---
> >   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 c43a9e28995e..6201aab374e6 100644
> > --- a/drivers/char/tpm/tpm-interface.c
> > +++ b/drivers/char/tpm/tpm-interface.c
> > @@ -587,7 +587,7 @@ ssize_t tpm_transmit(struct tpm_chip *chip, struct tpm_space *space,
> >   		 */
> >   		if (rc == TPM2_RC_TESTING && cc == TPM2_CC_SELF_TEST)
> >   			break;
> > -		delay_msec *= 2;
> > +
> Extra whitespace

I left just for clarity, but if not needed then I can remove it.

Thanks & Regards,
ÂÂ - Nayna

> >   		if (delay_msec > TPM2_DURATION_LONG) {
> >   			if (rc == TPM2_RC_RETRY)
> >   				dev_err(&chip->dev, "in retry loop\n");
> > @@ -597,6 +597,7 @@ ssize_t tpm_transmit(struct tpm_chip *chip, struct tpm_space *space,
> >   			break;
> >   		}
> >   		tpm_msleep(delay_msec);
> > +		delay_msec *= 2;
> >   		memcpy(buf, save, save_size);
> >   	}
> >   	return ret;
> > --
> > 2.13.6
> /Jarkko