diff options
| author | Paul E. McKenney <paulmck@kernel.org> | 2019-12-22 19:39:35 -0800 |
|---|---|---|
| committer | Paul E. McKenney <paulmck@kernel.org> | 2020-02-20 16:01:11 -0800 |
| commit | 39f91504a03a7a2abdb52205106942fa4a548d0d (patch) | |
| tree | 21148b0b3bd1e4c676a50e9414e5a919fd85350c /kernel/rcu | |
| parent | 8c9e0cb32315835825ea1ad725a858a2d2ce4a8e (diff) | |
srcu: Fix process_srcu()/srcu_batches_completed() datarace
The srcu_struct structure's ->srcu_idx field is accessed locklessly,
so reads must use READ_ONCE(). This commit therefore adds the needed
READ_ONCE() invocation where it was missed.
This data race was reported by KCSAN. Not appropriate for backporting
due to failure being unlikely.
Signed-off-by: Paul E. McKenney <paulmck@kernel.org>
Diffstat (limited to 'kernel/rcu')
| -rw-r--r-- | kernel/rcu/srcutree.c | 2 |
1 files changed, 1 insertions, 1 deletions
diff --git a/kernel/rcu/srcutree.c b/kernel/rcu/srcutree.c index 79848f7d575d..119a37319e67 100644 --- a/kernel/rcu/srcutree.c +++ b/kernel/rcu/srcutree.c @@ -1079,7 +1079,7 @@ EXPORT_SYMBOL_GPL(srcu_barrier); */ unsigned long srcu_batches_completed(struct srcu_struct *ssp) { - return ssp->srcu_idx; + return READ_ONCE(ssp->srcu_idx); } EXPORT_SYMBOL_GPL(srcu_batches_completed); |