Files
Linux/include
Nikanth Karthikesan d9c7d394a8 block: prevent possible io_context->refcount overflow
Currently io_context has an atomic_t(32-bit) as refcount.  In the case of
cfq, for each device against whcih a task does I/O, a reference to the
io_context would be taken.  And when there are multiple process sharing
io_contexts(CLONE_IO) would also have a reference to the same io_context.

Theoretically the possible maximum number of processes sharing the same
io_context + the number of disks/cfq_data referring to the same io_context
can overflow the 32-bit counter on a very high-end machine.

Even though it is an improbable case, let us make it atomic_long_t.

Signed-off-by: Nikanth Karthikesan <[email protected]>
Signed-off-by: Andrew Morton <[email protected]>
Signed-off-by: Jens Axboe <[email protected]>
2009-06-10 23:07:15 +02:00
..
…
…
…
2009-05-06 12:32:26 +02:00
…
…