On Sat, Mar 25, 2017 at 05:21:30AM -0700, Jerry Snitselaar wrote: > > Jarkko Sakkinen @ 2017-03-24 10:19 GMT: > > > On Fri, Mar 24, 2017 at 12:10:30PM +0200, Jarkko Sakkinen wrote: > >> This commit adds support for requesting and relinquishing locality 0 in > >> tpm_crb for the course of command transmission. > >> > >> In order to achieve this, two new callbacks are added to struct > >> tpm_class_ops: > >> > >> - request_locality > >> - relinquish_locality > >> > >> With CRB interface you first set either requestAccess or relinquish bit > >> from TPM_LOC_CTRL_x register and then wait for locAssigned and > >> tpmRegValidSts bits to be set in the TPM_LOC_STATE_x register. > >> > >> The reason why were are doing this is to make sure that the driver > >> will work properly with Intel TXT that uses locality 2. There's no > >> explicit guarantee that it would relinquish this locality. In more > >> general sense this commit enables tpm_crb to be a well behaving > >> citizen in a multi locality environment. > >> > >> Signed-off-by: Jarkko Sakkinen <[email protected]> > >> --- > >> v2: > >> - TPM driver level calllbacks > >> v3: > >> - Call ops->relinquish_locality only if ops->request_locality has been > >> successful. > >> - Do not reserve locality in nested tpm_transmit calls. > >> - Check for tpmRegValidSts to make sure that the value in TPM_LOC_STATE_x > >> is > >> stable. > >> v4: > >> - Removed tpm_tis_core changes. It needs to be done separately. It will be > >> postponed to 4.13. > >> - Store locality to struct tpm_chip while active. > >> drivers/char/tpm/tpm-chip.c | 1 + > >> drivers/char/tpm/tpm-interface.c | 13 +++++++++++++ > >> drivers/char/tpm/tpm.h | 3 +++ > >> drivers/char/tpm/tpm_crb.c | 41 > >> ++++++++++++++++++++++++++++++++++++++++ > >> include/linux/tpm.h | 3 ++- > >> 5 files changed, 60 insertions(+), 1 deletion(-) > >> > >> diff --git a/drivers/char/tpm/tpm-chip.c b/drivers/char/tpm/tpm-chip.c > >> index aade699..a321bd5 100644 > >> --- a/drivers/char/tpm/tpm-chip.c > >> +++ b/drivers/char/tpm/tpm-chip.c > >> @@ -231,6 +231,7 @@ struct tpm_chip *tpm_chip_alloc(struct device *pdev, > >> goto out; > >> } > >> > >> + chip->locality = -1; > >> return chip; > >> > >> out: > >> diff --git a/drivers/char/tpm/tpm-interface.c > >> b/drivers/char/tpm/tpm-interface.c > >> index 95c6f98..1815666 100644 > >> --- a/drivers/char/tpm/tpm-interface.c > >> +++ b/drivers/char/tpm/tpm-interface.c > >> @@ -384,6 +384,7 @@ ssize_t tpm_transmit(struct tpm_chip *chip, struct > >> tpm_space *space, > >> ssize_t len = 0; > >> u32 count, ordinal; > >> unsigned long stop; > >> + bool need_locality = chip->locality == -1; > > > > This must be set *after* taking the mutex. Otherwise, I think this > > should be fine now. > > > > /Jarkko > > Sorry, I missed this email earlier. Yeah, I ran into this while trying to get > the > tpm_tis code working with this change tonight. Are you just going to move the > assignment to right before the if block for request_locality? I've > tested with the assignment moved inside the mutex on a kabylake > system. > > I also tested with a patch for adding support to tpm_tis on a tpm_tis > system, but that is a work in progress.
Yes. It's like that now in the locality branch in my tree. /Jarkko ------------------------------------------------------------------------------ Check out the vibrant tech community on one of the world's most engaging tech sites, Slashdot.org! http://sdm.link/slashdot _______________________________________________ tpmdd-devel mailing list [email protected] https://lists.sourceforge.net/lists/listinfo/tpmdd-devel
