From: Jason Gunthorpe <jgunthorpe@obsidianresearch.com>
To: Valdis.Kletnieks@vt.edu
Cc: Hal Finney <hal.finney@gmail.com>,
tpmdd-devel@lists.sourceforge.net, linux-kernel@vger.kernel.org,
srajiv@linux.vnet.ibm.com
Subject: Re: [tpmdd-devel] [PATCH] TPM: Let the tpm char device be openable multiple times
Date: Tue, 3 Nov 2009 15:41:58 -0700 [thread overview]
Message-ID: <20091103224157.GA20963@obsidianresearch.com> (raw)
In-Reply-To: <6926.1257272068@turing-police.cc.vt.edu>
On Tue, Nov 03, 2009 at 01:14:28PM -0500, Valdis.Kletnieks@vt.edu wrote:
> On Tue, 03 Nov 2009 09:31:55 PST, Hal Finney said:
> > What if you don't want it accessible by user mode apps, you only want
> > your middleware (ie tcs daemon, tcsd) to open it? Will this still
> > allow that to be enforced, so nobody can interfere with tcsd's
> > exclusive access to the device?
>
> Couldn't tcsd just open the device with O_EXCL? Or am I missing something
> subtle here?
O_EXCL isn't a locking flag...
O_EXCL Ensure that this call creates the file: if this flag is specified in conjunction with O_CREAT, and
pathname already exists, then open() will fail. The behavior of O_EXCL is undefined if O_CREAT is not
specified.
Jason
next prev parent reply other threads:[~2009-11-03 22:42 UTC|newest]
Thread overview: 16+ messages / expand[flat|nested] mbox.gz Atom feed top
2009-11-03 0:35 [PATCH] TPM: Let the tpm char device be openable multiple times Jason Gunthorpe
2009-11-03 10:43 ` Alan Cox
2009-11-03 17:15 ` Jason Gunthorpe
2009-11-03 17:31 ` [tpmdd-devel] " Hal Finney
2009-11-03 17:46 ` Jason Gunthorpe
2009-11-03 18:14 ` Valdis.Kletnieks
2009-11-03 22:41 ` Jason Gunthorpe [this message]
2009-11-04 3:24 ` Valdis.Kletnieks
2009-11-04 4:27 ` Jason Gunthorpe
2009-11-04 9:58 ` Alan Cox
-- strict thread matches above, loose matches on Subject: below --
2012-09-30 23:33 Jason Gunthorpe
2012-10-01 9:07 ` [tpmdd-devel] " Peter.Huewe
2012-10-01 16:09 ` Jason Gunthorpe
2012-10-10 16:33 ` Kent Yoder
2012-10-12 20:56 ` Jason Gunthorpe
2012-10-15 8:35 ` [tpmdd-devel] " Peter.Huewe
2012-10-15 16:39 ` Jason Gunthorpe
2012-10-15 16:49 ` Alan Cox
2012-10-15 16:56 ` Jason Gunthorpe
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