Messages in this thread | | | Date | Wed, 11 Apr 2012 02:54:31 +0400 | From | Cyrill Gorcunov <> | Subject | Re: + syscalls-x86-add-__nr_kcmp-syscall-v8.patch added to -mm tree |
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On Mon, Apr 09, 2012 at 08:25:22PM -0700, Eric W. Biederman wrote: ... > > Having just read through it again the only possible issue I can see is > that we compare file descriptors after dropping all of the locks. > > Since rcu_read_lock doesn't participate in ABBA deadlocks. My gut feel > is that we should hold rcu_read_lock across the hole file pointer > comparison to remove the possibility of races as file descriptor > pointers go away. > > Still in practice I don't think it matters. At worst there is the > slightest possibility of returning a value instead of -EBADF. The > expectation is for all of the tasks we are operating on to be frozen, > and even if the tasks are not frozen it is a very tiny window for a race > to be in.
yeah, we use this call heavily on stopped tasks atm
> > So what do people think? Any issues? Any nacks? Should I sneak it > > into Linus this week or do we need to go another round with it all? > > Acked-by: "Eric W. Biederman" <ebiederm@xmission.com> >
Thanks a lot, Eric!
Cyrill
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