On 11/4/24 15:36, James Bottomley wrote:
On Mon, 2024-11-04 at 11:34 -0500, Daniel P. Smith wrote:
[...]
In case the question comes up from those not familiar, the kexec does
an GETSEC[SEXIT] which closes off access to Localities 1 and 2, thus
locking the DRTM PCR values. It brings the CPUs out of SMX mode so
the target kernel does not require to have any knowledge about
running in that mode.
So, to repeat the question: why a sysfs interface for setting the
default locality? If I understand correctly from what you say above,
it can't be used in any kernel except the SL one, and that one could
run permanently in it, so there's no requirement at all for user space
to be able to change this, is there?
I responded to Ard this morning that, "If the slmodule is able to set
the locality for all PCR extends coming from user space to be Locality
2, that removes the current need for it." Where "it" is the sysfs node
for default locality. This series does just that, so in a more direct
response, no, a writable sysfs node is no longer needed with this series.
v/r
dps
