From mboxrd@z Thu Jan 1 00:00:00 1970 From: Jarkko Sakkinen Subject: Re: [PATCH] tpm: fix crash in tpm_tis deinitialization Date: Wed, 13 Apr 2016 09:58:05 +0300 Message-ID: <20160413065805.GB6986@intel.com> References: <1460390720-9509-1-git-send-email-jarkko.sakkinen@linux.intel.com> <20160411174037.GA371@obsidianresearch.com> <20160412042627.GA6608@intel.com> <20160412172655.GA5759@obsidianresearch.com> <20160413061651.GA6986@intel.com> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Return-path: Content-Disposition: inline In-Reply-To: <20160413061651.GA6986@intel.com> Sender: linux-kernel-owner@vger.kernel.org To: Jason Gunthorpe Cc: Peter Huewe , Marcel Selhorst , "moderated list:TPM DEVICE DRIVER" , open list List-Id: tpmdd-devel@lists.sourceforge.net On Wed, Apr 13, 2016 at 09:16:51AM +0300, Jarkko Sakkinen wrote: > On Tue, Apr 12, 2016 at 11:26:55AM -0600, Jason Gunthorpe wrote: > > On Tue, Apr 12, 2016 at 07:26:27AM +0300, Jarkko Sakkinen wrote: > > > > This needs to be after ops is fenced, something like this. > > > > > > I would appreciate a supporting argument. > > > > > > I guess the argument here is that this will prevent user space from > > > issuing TPM commands after the shutdown command has been sent? > > > > It prevents everything including the kernel from issuing a command > ^^^^^^^^^^^^^^^^^^^^ > > That lock is not used to exclude kernel access. Read lock is only taken > for the user space device in tpm-dev.c. My bad. For the in-kernel API it is taken through tpm_find_get(). I'll update the fix. /Jarkko