summaryrefslogtreecommitdiff
path: root/Documentation/kmemleak.txt
diff options
context:
space:
mode:
authorTejun Heo <tj@kernel.org>2011-11-21 12:32:22 -0800
committerTejun Heo <tj@kernel.org>2011-11-21 12:32:22 -0800
commit50fb4f7fc907efff65eadb0b74387a9ffed6e849 (patch)
treee3392afa49a97c187d7e63f3fee862aef9e342ed /Documentation/kmemleak.txt
parent6fe4c6d466e95d31164f14b1ac4aefb51f0f4f82 (diff)
freezer: fix current->state restoration race in refrigerator()
refrigerator() saves current->state before entering frozen state and restores it before returning using __set_current_state(); however, this is racy, for example, please consider the following sequence. set_current_state(TASK_INTERRUPTIBLE); try_to_freeze(); if (kthread_should_stop()) break; schedule(); If kthread_stop() races with ->state restoration, the restoration can restore ->state to TASK_INTERRUPTIBLE after kthread_stop() sets it to TASK_RUNNING but kthread_should_stop() may still see zero ->should_stop because there's no memory barrier between restoring TASK_INTERRUPTIBLE and kthread_should_stop() test. This isn't restricted to kthread_should_stop(). current->state is often used in memory barrier based synchronization and silently restoring it w/o mb breaks them. Use set_current_state() instead. Signed-off-by: Tejun Heo <tj@kernel.org>
Diffstat (limited to 'Documentation/kmemleak.txt')
0 files changed, 0 insertions, 0 deletions