diff options
author | WANG Cong <xiyou.wangcong@gmail.com> | 2016-11-17 15:55:26 -0800 |
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committer | Greg Kroah-Hartman <gregkh@linuxfoundation.org> | 2016-12-10 19:07:22 +0100 |
commit | 6ef59b986190f07386b062884ab48006c16cf152 (patch) | |
tree | ae661a5768e3ceec75475fbbc9c20d8267720c7e /net/core/rtnetlink.c | |
parent | acf9504ae220acbd1caa8ee4668c8a3a3b51d73a (diff) |
af_unix: conditionally use freezable blocking calls in read
[ Upstream commit 06a77b07e3b44aea2b3c0e64de420ea2cfdcbaa9 ]
Commit 2b15af6f95 ("af_unix: use freezable blocking calls in read")
converts schedule_timeout() to its freezable version, it was probably
correct at that time, but later, commit 2b514574f7e8
("net: af_unix: implement splice for stream af_unix sockets") breaks
the strong requirement for a freezable sleep, according to
commit 0f9548ca1091:
We shouldn't try_to_freeze if locks are held. Holding a lock can cause a
deadlock if the lock is later acquired in the suspend or hibernate path
(e.g. by dpm). Holding a lock can also cause a deadlock in the case of
cgroup_freezer if a lock is held inside a frozen cgroup that is later
acquired by a process outside that group.
The pipe_lock is still held at that point.
So use freezable version only for the recvmsg call path, avoid impact for
Android.
Fixes: 2b514574f7e8 ("net: af_unix: implement splice for stream af_unix sockets")
Reported-by: Dmitry Vyukov <dvyukov@google.com>
Cc: Tejun Heo <tj@kernel.org>
Cc: Colin Cross <ccross@android.com>
Cc: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Cc: Hannes Frederic Sowa <hannes@stressinduktion.org>
Signed-off-by: Cong Wang <xiyou.wangcong@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Diffstat (limited to 'net/core/rtnetlink.c')
0 files changed, 0 insertions, 0 deletions