linux-kernel - Re: [PATCH] tpm: moves the delay_msec increment after sleep in tpm

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Message-ID: <20180407103610.GA22542@linux.intel.com>
Date:   Sat, 7 Apr 2018 13:36:10 +0300
From:   Jarkko Sakkinen <jarkko.sakkinen@...ux.intel.com>
To:     Nayna Jain <nayna@...ux.vnet.ibm.com>
Cc:     linux-integrity@...r.kernel.org, zohar@...ux.vnet.ibm.com,
        linux-security-module@...r.kernel.org,
        linux-kernel@...r.kernel.org, peterhuewe@....de,
        tpmdd@...horst.net, jgunthorpe@...idianresearch.com
Subject: Re: [PATCH] tpm: moves the delay_msec increment after sleep in
 tpm_transmit()

On Fri, Apr 06, 2018 at 02:03:37PM +0530, Nayna Jain wrote:
> 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.

So the problem is that the loop doubles the time before sleeping
for the first time. This is missing from the description. Please
refine it in some way.

/Jarkko