From: "Hans J. Koch" <hjk@hansjkoch.de>
To: Greg KH <gregkh@linuxfoundation.org>
Cc: Benedikt Spranger <b.spranger@linutronix.de>,
linux-kernel@vger.kernel.org, hjk@hansjkoch.de,
Alexander.Frank@eberspaecher.com
Subject: Re: [PATCH 2/2] uio: do not expose inode to uio open/release hooks
Date: Wed, 12 Dec 2012 02:42:22 +0100 [thread overview]
Message-ID: <20121212014221.GA2642@local> (raw)
In-Reply-To: <20121211232032.GA24933@kroah.com>
On Tue, Dec 11, 2012 at 03:20:32PM -0800, Greg KH wrote:
> On Wed, Dec 12, 2012 at 12:12:02AM +0100, Benedikt Spranger wrote:
> > The inode parameter is unused by in kernel users of UIO.
>
> Ok.
>
> > Also the inode parameter makes it hard to resolve the existing open(),
> > mmap() and close() difficulty.
>
> I don't understand, what do you mean by this? What is this parameter
> causing problems with?
The problem is that according to POSIX, it is guaranteed that in userspace
you can do
fd = open("/dev/uio0", ...)
ptr = mmap(...fd...)
close(fd)
with ptr still being valid and useable after that.
Thanks,
Hans
next prev parent reply other threads:[~2012-12-12 1:42 UTC|newest]
Thread overview: 16+ messages / expand[flat|nested] mbox.gz Atom feed top
2012-12-11 23:12 [PATCH 0/2] uio: open(), mmap(), close() Benedikt Spranger
2012-12-11 23:12 ` [PATCH 1/2] uio: add warning to documentation Benedikt Spranger
2012-12-11 23:18 ` Greg KH
2012-12-12 0:45 ` Benedikt Spranger
2012-12-12 4:49 ` Greg KH
2012-12-12 1:56 ` Hans J. Koch
2012-12-12 4:47 ` Greg KH
2012-12-11 23:12 ` [PATCH 2/2] uio: do not expose inode to uio open/release hooks Benedikt Spranger
2012-12-11 23:20 ` Greg KH
2012-12-12 1:42 ` Hans J. Koch [this message]
2012-12-12 4:46 ` Greg KH
2012-12-12 8:50 ` Hans J. Koch
2012-12-12 8:56 ` Benedikt Spranger
2012-12-12 15:08 ` Greg KH
2012-12-13 0:08 ` Hans J. Koch
2012-12-13 0:15 ` Greg KH
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