On Tue, Oct 24, 2017 at 09:37:33PM +0530, PrasannaKumar Muralidharan wrote: > Hi Jason, > > On 24 October 2017 at 21:25, Jason Gunthorpe > <jgunthorpe@xxxxxxxxxxxxxxxxxxxx> wrote: > > On Tue, Oct 24, 2017 at 09:21:15PM +0530, PrasannaKumar Muralidharan wrote: > > > >> Please check the RFC [1]. It does use chip id. The rfc has issues and > >> has to be fixed but still there could be users of the API. > >> > >> 1. https://www.spinics.net/lists/linux-crypto/msg28282.html > > > > That patch isn't safe at all. You need to store a kref to th chip in > > the hwrng, not parse a string. > > The drivers/char/hw_random/tpm-rng.c module does not store the chip > reference so I guess the usage is safe. It is using the default TPM, it is always safe to use the default tpm. > The RFC is just a sample use case of the API. Well, a wrong example not to be emulated, and I think, further shows how Jarkko's direction is the right one. Jason
