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    SubjectRe: TPM chip prevents machine from suspending
    On 03/29/2011 10:30 AM, Rajiv Andrade wrote:
    > On 03/29/2011 09:25 AM, Stefan Berger wrote:
    >> On 03/29/2011 08:08 AM, Jeff Layton wrote:
    >>>>> Is there some way short of recompiling with CONFIG_TCG_* turned off
    >>> to disable the TPM driver at boot time?
    >>>
    >> As far as I know, 'no'. I'd defer it to the maintainers as to how they would want to solve your particular problem... either by using above work-around, which would be more transparent, or actively having to turn the driver off with a command line parameter.
    >>
    >> Stefan
    >>
    > I'm handling a patch from Stefan that solves so, for now,
    > I'd recommend to use Stefan's tool.

    Well, at least none of the patches I submitted in the series solves this
    particular problem.

    I am not sure whether this problem should be fixed since it's hopefully
    rare. If it was to be fixed, how it should be fixed. Here are a couple
    of options:

    - declare it a lost case due to broken out-of-spec BIOS -- don't fix it;
    machine won't suspend a 2nd time

    - send a command to the TPM upon resume and if TPM response returns
    with error code 38 set a flag and don't send TPM_SaveState() upon the
    next suspend; log this case; the TPM becomes unusable; machine will
    suspend a 2nd time

    - send a command to the TPM upon resume and if it returns with error
    code 38 send TPM_Startup(ST_STATE) -> this masks the BIOS problem; log
    this case; TPM stays usable; machine will suspend a 2nd time; a
    colleague tells me it may not be 'safe'

    Options 2 and 3 would now also run for all the rest of the machines with
    a good BIOS...

    Stefan



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