Re: [PATCH] TPM: Retry SaveState command in suspend path

[Greg KH <gregkh@linuxfoundation.org>]

On Tue, Mar 19, 2013 at 10:00:02AM -0500, Kent Yoder wrote:
> Hi Duncan,
> 
> On Sun, Mar 17, 2013 at 4:56 PM, Duncan Laurie <dlaurie@chromium.org> wrote:
> > If the TPM has already been sent a SaveState command before the driver
> > is loaded it may have problems sending that same command again later.
> >
> > This issue is seen with the Chromebook Pixel due to a firmware bug in
> > the legacy mode boot path which is sending the SaveState command
> > before booting the kernel.  More information is available at
> > http://crbug.com/203524
> >
> > This change introduces a retry of the SaveState command in the suspend
> > path in order to work around this issue.  A future firmware update
> > should fix this but this is also a trivial workaround in the driver
> > that has no effect on systems that do not show this problem.
> 
>   I'm not convinced that this needs to be upstream.  The simplest
> route would seem to be to carry this out of tree until your firmware
> is fixed.

Really?  We have machines that we are using right now that need this fix
in order to work properly.

The kernel handles buggy firmware/bioses all the time, we need to work
properly on all hardware, we can't count on a firmware update ever
getting pushed out publically, and for those of us using this hardware,
we want it to work.

So, please accept this patch,

thanks,

greg l-h