On Tue, Sep 30, 2014 at 02:12:09PM -0600, Jason Gunthorpe wrote: > On Tue, Sep 30, 2014 at 11:07:21PM +0300, Jarkko Sakkinen wrote: > > On Fri, Sep 26, 2014 at 08:19:47PM +0300, Jarkko Sakkinen wrote: > > > On Wed, Sep 24, 2014 at 02:46:27PM -0600, Jason Gunthorpe wrote: > > > > > That would be 24*2 files only for pcrs... > > > > > > > > Some subsystems do just that.. > > > > > > > > $ ls /sys/class/infiniband/qib0/ports/1/sl2vl/ > > > > 0 1 10 11 12 13 14 15 2 3 4 5 6 7 8 9 > > > > > > They use static structures in > > > drivers/infiniband/hw/qib/qib_sysfs.c and it does not looks a > > > mess. I would prefer to create struct attribute entries > > > dynamically if there's clean and easy way to do that. > > > > I gave this a shot: > > > > https://github.com/jsakkine/linux-tpm2/commit/dffce68ce34da265a62908dec71b2d85fc16824f > > > > I want to initialize dynamically so that it is easy to support > > TPM_PT_PCR_COUNT later. > > You can't use a static pcr_dev_attrs, this has to be allocated in the > chip structure (because of the NULL). Otherwise looks about right > (although there are more problematic core details here, like racing of the > tpm dev create with the creation of the sysfs files)
I improved things and pushed a commit that encapsulates PCR bank into struct pcrs_kobj (internal struct in tpm2-sysfs.c). This brings me to my question. In TPM2 there is not just PCR bank with SHA-1 hashes but there are multiple PCR banks. The way I plan to represent this is: pcrs/<tag for banks hash algorithm>/<PCR index> My last commit provides most of the code for implementing this although in the initial patch set I would take a short cut and only show SHA-1 PCRs. The important thing is that it is put into pcrs/sha1 directory. > Do you have a reason to have the pcrs in sysfs? I'd be just as happy > to see them dropped or moved to debugfs for TPM2 as well. Well, I at least find it useful debugging tool sometimes. And now it is more useful because PCR values are machine readable. I will include this to the v2 patch set. When we have a clean patch set with all the fixes applied into tpm2-v1 branch it will be a better time to evaluate what is mandatory and what can be postponed. > Jason /Jarkko -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majord...@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
