From: Jason Gunthorpe <jgunthorpe-ePGOBjL8dl3ta4EC/59zMFaTQe2KTcn/@public.gmane.org>
To: James Bottomley <jejb-23VcF4HTsmIX0ybBhKVfKdBPR1lH4CV8@public.gmane.org>
Cc: tpmdd-devel-5NWGOfrQmneRv+LV9MX5uipxlwaOVQ5f@public.gmane.org,
Ken Goldman <kgoldman-r/Jw6+rmf7HQT0dZR+AlfA@public.gmane.org>
Subject: Re: TPM 2.0 device driver blocking open
Date: Tue, 3 Jan 2017 14:26:12 -0700 [thread overview]
Message-ID: <20170103212612.GA29656@obsidianresearch.com> (raw)
In-Reply-To: <1483123609.2712.1.camel-23VcF4HTsmIX0ybBhKVfKdBPR1lH4CV8@public.gmane.org>
On Fri, Dec 30, 2016 at 10:46:49AM -0800, James Bottomley wrote:
> Just FYI this is the temporary hack I'm using to fix my multiple access
> problem while Jarkko is working on the RM as the final solution. All
> it does is block a second and subsequent open until the first one
> completes.
This is how it should have been in the first place, with O_NONBLOCK to
return immediately..
The only reason I never fixed it is because of fears that userspace
will go wrong if the open() starts to block forever. If someone knows
the common userspace is generally OK then let us merge a patch like
this...
Jason
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next prev parent reply other threads:[~2017-01-03 21:26 UTC|newest]
Thread overview: 6+ messages / expand[flat|nested] mbox.gz Atom feed top
2016-12-30 15:53 TPM 2.0 device driver blocking open Ken Goldman
2016-12-30 16:22 ` James Bottomley
[not found] ` <1483114928.2442.28.camel-23VcF4HTsmIX0ybBhKVfKdBPR1lH4CV8@public.gmane.org>
2016-12-30 18:46 ` James Bottomley
[not found] ` <1483123609.2712.1.camel-23VcF4HTsmIX0ybBhKVfKdBPR1lH4CV8@public.gmane.org>
2017-01-03 21:26 ` Jason Gunthorpe [this message]
2017-01-02 15:15 ` Fuchs, Andreas
[not found] ` <9F48E1A823B03B4790B7E6E69430724DC7C1378B-pTbww/UJF9iZbMGAS439G2SU2VBt9E6NG9Ur7JDdleE@public.gmane.org>
2017-01-02 16:25 ` James Bottomley
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