diff options
| author | Tejun Heo <tj@kernel.org> | 2016-05-25 11:48:25 -0400 |
|---|---|---|
| committer | Greg Kroah-Hartman <gregkh@linuxfoundation.org> | 2016-07-27 09:47:33 -0700 |
| commit | 3bb1138e7760404fb801f0b656f85d2fcfc2c39d (patch) | |
| tree | 36eb1386049c1efcfbe42479430aa8c76d51026d /fs/btrfs | |
| parent | c26ae537f16f653c2541df9e338013653fc3fcc7 (diff) | |
percpu: fix synchronization between synchronous map extension and chunk destruction
commit 6710e594f71ccaad8101bc64321152af7cd9ea28 upstream.
For non-atomic allocations, pcpu_alloc() can try to extend the area
map synchronously after dropping pcpu_lock; however, the extension
wasn't synchronized against chunk destruction and the chunk might get
freed while extension is in progress.
This patch fixes the bug by putting most of non-atomic allocations
under pcpu_alloc_mutex to synchronize against pcpu_balance_work which
is responsible for async chunk management including destruction.
Signed-off-by: Tejun Heo <tj@kernel.org>
Reported-and-tested-by: Alexei Starovoitov <alexei.starovoitov@gmail.com>
Reported-by: Vlastimil Babka <vbabka@suse.cz>
Reported-by: Sasha Levin <sasha.levin@oracle.com>
Fixes: 1a4d76076cda ("percpu: implement asynchronous chunk population")
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Diffstat (limited to 'fs/btrfs')
0 files changed, 0 insertions, 0 deletions