diff options
| author | Al Viro <viro@zeniv.linux.org.uk> | 2013-03-26 23:25:57 +0100 |
|---|---|---|
| committer | Al Viro <viro@zeniv.linux.org.uk> | 2013-03-26 23:25:57 +0100 |
| commit | 7ea600b5314529f9d1b9d6d3c41cb26fce6a7a4a (patch) | |
| tree | 8cc99c507999dcb7c35e973e22d79ae9a3ac8165 /drivers/clk/clk-devres.c | |
| parent | Don't bother with redoing rw_verify_area() from default_file_splice_from() (diff) | |
| download | linux-7ea600b5314529f9d1b9d6d3c41cb26fce6a7a4a.tar.xz linux-7ea600b5314529f9d1b9d6d3c41cb26fce6a7a4a.zip | |
Nest rename_lock inside vfsmount_lock
... lest we get livelocks between path_is_under() and d_path() and friends.
The thing is, wrt fairness lglocks are more similar to rwsems than to rwlocks;
it is possible to have thread B spin on attempt to take lock shared while thread
A is already holding it shared, if B is on lower-numbered CPU than A and there's
a thread C spinning on attempt to take the same lock exclusive.
As the result, we need consistent ordering between vfsmount_lock (lglock) and
rename_lock (seq_lock), even though everything that takes both is going to take
vfsmount_lock only shared.
Spotted-by: Brad Spengler <spender@grsecurity.net>
Cc: stable@vger.kernel.org
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
Diffstat (limited to 'drivers/clk/clk-devres.c')
0 files changed, 0 insertions, 0 deletions