On Mon, 2017-01-23 at 16:04 -0700, Jason Gunthorpe wrote: > On Mon, Jan 23, 2017 at 02:57:11PM -0800, James Bottomley wrote: > > On Mon, 2017-01-23 at 15:49 -0700, Jason Gunthorpe wrote: > > > On Mon, Jan 23, 2017 at 02:28:23PM -0800, James Bottomley wrote: > > > > On Mon, 2017-01-23 at 09:47 -0700, Jason Gunthorpe wrote: > > > > > On Mon, Jan 23, 2017 at 01:44:32AM +0200, Jarkko Sakkinen > > > > > wrote: > > > > > > From: James Bottomley < > > > > > > [email protected]> > > > > > > > > > > > > Signed-off-by: James Bottomley > > > > > > <[email protected]> > > > > > > > > > > I really think we should not use the ugly read/write > > > > > interface for any new things. > > > > > > > > The R/W interface is needed for backward compat, > > > > > > With what? This is a new cdev with different semantics. > > > > If you set TPM_DEVICE=/dev/tpms0 the old software just works. If > > we remove the R/W interface, nothing will work. The point being > > the new cdev has the same interface semantics, it just has > > different global behavour. > > So you are saying there is so much already deployed TPM2 software > that has this TPM_DEVICE env var convention that we need to support > it with compat? > > I'm really surprised by that.. But OK. > > Can you at least remove the 'user_read_timer' junk from the new cdev?
What's the problem with it? Can we not just fix whatever the issue is? I'd rather reuse all the R/W machinery as is. If I start trying to special case it so that we only use some parts on some control flows, the chances are I'll introduce additional bugs as well. James
