|| ||Arjan van de Ven <arjan-AT-infradead.org>|
|| ||Olof Johansson <olof-AT-austin.ibm.com>|
|| ||Re: [PATCH/RFC] Futex mmap_sem deadlock|
|| ||Wed, 23 Feb 2005 18:37:01 +0100|
|| ||Linus Torvalds <torvalds-AT-osdl.org>, Joe Korty <joe.korty-AT-ccur.com>,
Jamie Lokier <jamie-AT-shareable.org>,
Andrew Morton <akpm-AT-osdl.org>, linux-kernel-AT-vger.kernel.org,
On Wed, 2005-02-23 at 11:10 -0600, Olof Johansson wrote:
> On Wed, Feb 23, 2005 at 07:54:06AM -0800, Linus Torvalds wrote:
> > > Otherwise, a preempt attempt in get_user would not be seen
> > > until some future preempt_enable was executed.
> > True. I guess we should have a "preempt_check_resched()" there too. That's
> > what "kunmap_atomic()" does too (which is what we rely on in the other
> > case we do this..)
> Ok, this is getting complex enough to warrant get_user_inatomic(),
> which means adding it to every arch's uaccess.h.
> Below patch does so. Unfortunately I don't have a Viro setup with cross
> compilers for nearly every arch, so I can't make sure it doesn't break
> anything. But since I pasted the same code everywhere it shouldn't.
I hate to do this to you, but get_user is a bit horrible in that it is
an untyped interface. Fixing it is hard (ugh) but when adding new
variants should/could we consider to please make it a typed (eg inline
and not a define) interface please ?
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