From mboxrd@z Thu Jan 1 00:00:00 1970 From: James.Bottomley@HansenPartnership.com (James Bottomley) Date: Fri, 10 Aug 2018 12:00:47 -0700 Subject: [PATCH v4 2/2] tpm: add support for nonblocking operation In-Reply-To: References: <153367365951.18015.11320230309813817454.stgit@tstruk-mobl1.jf.intel.com> <153367366969.18015.14742040525393494830.stgit@tstruk-mobl1.jf.intel.com> <20180810174320.GV4692@linux.intel.com> <1533926908.3143.6.camel@HansenPartnership.com> Message-ID: <1533927647.3143.7.camel@HansenPartnership.com> To: linux-security-module@vger.kernel.org List-Id: linux-security-module.vger.kernel.org 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