diff options
| author | Paul E. McKenney <paulmck@linux.vnet.ibm.com> | 2016-08-23 06:51:47 -0700 |
|---|---|---|
| committer | Paul E. McKenney <paulmck@linux.vnet.ibm.com> | 2016-11-14 10:46:08 -0800 |
| commit | b8f2ed538477d9ab803c6458f497df1b1c6cf4ce (patch) | |
| tree | 60ba4899c6b8c4dc48a727209a94435c21980647 | |
| parent | 1001354ca34179f3db924eb66672442a173147dc (diff) | |
rcu: Tighten up __call_rcu() rcu_head alignment check
Commit 720abae3d68ae ("rcu: force alignment on struct
callback_head/rcu_head") forced the rcu_head (AKA callback_head)
structure's alignment to pointer size, that is, to 4-byte boundaries on
32-bit systems and to 8-byte boundaries on 64-bit systems. This
commit therefore checks for this same alignment in __call_rcu(),
which used to contain a looser check for two-byte alignment.
Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Tested-by: Geert Uytterhoeven <geert@linux-m68k.org>
Acked-by: Kirill A. Shutemov <kirill.shutemov@linux.intel.com>
Reviewed-by: Josh Triplett <josh@joshtriplett.org>
| -rw-r--r-- | kernel/rcu/tree.c | 4 |
1 files changed, 3 insertions, 1 deletions
diff --git a/kernel/rcu/tree.c b/kernel/rcu/tree.c index 69a5611a7e7c..37e4f7d2be0c 100644 --- a/kernel/rcu/tree.c +++ b/kernel/rcu/tree.c @@ -3121,7 +3121,9 @@ __call_rcu(struct rcu_head *head, rcu_callback_t func, unsigned long flags; struct rcu_data *rdp; - WARN_ON_ONCE((unsigned long)head & 0x1); /* Misaligned rcu_head! */ + /* Misaligned rcu_head! */ + WARN_ON_ONCE((unsigned long)head & (sizeof(void *) - 1)); + if (debug_rcu_head_queue(head)) { /* Probable double call_rcu(), so leak the callback. */ WRITE_ONCE(head->func, rcu_leak_callback); |