Re: [PATCH v4 2/2] tpm: add support for nonblocking operation

[James Bottomley]

On Fri, 2018-08-10 at 11:56 -0700, Tadeusz Struk wrote:
> On 08/10/2018 11:48 AM, James Bottomley wrote:
> > On Fri, 2018-08-10 at 11:21 -0700, Tadeusz Struk wrote:
> > > and the feedback I got from Jason was:
> > > 
> > > "I wonder if it is worth creating this when the first file is
> > > opened.. Lots of systems have TPMs but few use the userspace.."
> > > 
> > > so I changed this to allocate the WQ on first open. I think it
> > > makes sense, but I leave it to you to decide.
> > 
> > If the reason is to not create a wq unless it's needed, shouldn't
> > the condition actually be first open with flag O_NONBLOCK?
> > 
> 
> Not really because one can do:
> 
> int fd = open("/dev/tpm0", O_RDWR);
> fcntl(fd, F_SETFL, O_NONBLOCK);

so move the condition to first need to queue ...

James