Merge branch 'core-rcu-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip

Pull RCU updates from Ingo Molnar:
 "The main RCU changes in this development cycle were:

   - Miscellaneous fixes, including a change to call_rcu()'s rcu_head
     alignment check.

   - Security-motivated list consistency checks, which are disabled by
     default behind DEBUG_LIST.

   - Torture-test updates.

   - Documentation updates, yet again just simple changes"

* 'core-rcu-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  torture: Prevent jitter from delaying build-only runs
  torture: Remove obsolete files from rcutorture .gitignore
  rcu: Don't kick unless grace period or request
  rcu: Make expedited grace periods recheck dyntick idle state
  torture: Trace long read-side delays
  rcu: RCU_TRACE enables event tracing as well as debugfs
  rcu: Remove obsolete comment from __call_rcu()
  rcu: Remove obsolete rcu_check_callbacks() header comment
  rcu: Tighten up __call_rcu() rcu_head alignment check
  Documentation/RCU: Fix minor typo
  documentation: Present updated RCU guarantee
  bug: Avoid Kconfig warning for BUG_ON_DATA_CORRUPTION
  lib/Kconfig.debug: Fix typo in select statement
  lkdtm: Add tests for struct list corruption
  bug: Provide toggle for BUG on data corruption
  list: Split list_del() debug checking into separate function
  rculist: Consolidate DEBUG_LIST for list_add_rcu()
  list: Split list_add() debug checking into separate function

1 files changed, 17 insertions, 0 deletions

diff --git a/include/linux/bug.h b/include/linux/bug.h
index 292d6a10b0c2..baff2e8fc8a8 100644
--- a/include/linux/bug.h
+++ b/include/linux/bug.h
@@ -121,4 +121,21 @@ static inline enum bug_trap_type report_bug(unsigned long bug_addr,
 }
 
 #endif	/* CONFIG_GENERIC_BUG */
+
+/*
+ * Since detected data corruption should stop operation on the affected
+ * structures, this returns false if the corruption condition is found.
+ */
+#define CHECK_DATA_CORRUPTION(condition, fmt, ...)			 \
+	do {								 \
+		if (unlikely(condition)) {				 \
+			if (IS_ENABLED(CONFIG_BUG_ON_DATA_CORRUPTION)) { \
+				pr_err(fmt, ##__VA_ARGS__);		 \
+				BUG();					 \
+			} else						 \
+				WARN(1, fmt, ##__VA_ARGS__);		 \
+			return false;					 \
+		}							 \
+	} while (0)
+
 #endif	/* _LINUX_BUG_H */