linux-stable-rt/drivers/infiniband/core
Roland Dreier 24bce50803 IB/umem: Fix possible hang on process exit
If ib_umem_release() is called after ib_uverbs_close() sets context->closing,
then a process can get stuck in a D state, because the code boils down to

	if (down_write_trylock(&mm->mmap_sem))
		down_write(&mm->mmap_sem);

which is obviously a stupid instant deadlock.  Fix the code so that we
only try to take the lock once.

This bug was introduced in commit f7c6a7b5 ("IB/uverbs: Export
ib_umem_get()/ib_umem_release() to modules") which fortunately never
made it into a release, and was reported by Pete Wyckoff <pw@osc.edu>.

Signed-off-by: Roland Dreier <rolandd@cisco.com>
2007-06-21 11:05:58 -07:00
..
Makefile IB/uverbs: Export ib_umem_get()/ib_umem_release() to modules 2007-05-08 18:00:37 -07:00
addr.c
agent.c
agent.h
cache.c Detach sched.h from mm.h 2007-05-21 09:18:19 -07:00
cm.c IB/cm: Fix stale connection detection 2007-05-29 16:07:09 -07:00
cm_msgs.h
cma.c RDMA/cma: Fix initialization of next_port 2007-06-07 23:24:38 -07:00
core_priv.h
device.c Merge branch 'for-linus' of master.kernel.org:/pub/scm/linux/kernel/git/roland/infiniband 2007-05-21 16:19:32 -07:00
fmr_pool.c
iwcm.c
iwcm.h
mad.c
mad_priv.h
mad_rmpp.c
mad_rmpp.h
multicast.c
packer.c
sa.h
sa_query.c
smi.c
smi.h
sysfs.c
ucm.c
ucma.c
ud_header.c
umem.c IB/umem: Fix possible hang on process exit 2007-06-21 11:05:58 -07:00
user_mad.c
uverbs.h IB/uverbs: Export ib_umem_get()/ib_umem_release() to modules 2007-05-08 18:00:37 -07:00
uverbs_cmd.c IB/uverbs: Export ib_umem_get()/ib_umem_release() to modules 2007-05-08 18:00:37 -07:00
uverbs_main.c IB/uverbs: Export ib_umem_get()/ib_umem_release() to modules 2007-05-08 18:00:37 -07:00
uverbs_marshall.c
verbs.c