4.19-stable review patch. If anyone has any objections, please let me know.
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[ Upstream commit a39f15b9644fac3f950f522c39e667c3af25c588 ]
Since kprobe itself depends on RCU, probing on RCU debug routine can cause recursive breakpoint bugs.
Prohibit probing on RCU debug routines.
int3 ->do_int3() ->ist_enter() ->RCU_LOCKDEP_WARN() ->debug_lockdep_rcu_enabled() -> int3
Signed-off-by: Masami Hiramatsu mhiramat@kernel.org Cc: Alexander Shishkin alexander.shishkin@linux.intel.com Cc: Andrea Righi righi.andrea@gmail.com Cc: Arnaldo Carvalho de Melo acme@redhat.com Cc: Jiri Olsa jolsa@redhat.com Cc: Linus Torvalds torvalds@linux-foundation.org Cc: Mathieu Desnoyers mathieu.desnoyers@efficios.com Cc: Peter Zijlstra peterz@infradead.org Cc: Steven Rostedt rostedt@goodmis.org Cc: Thomas Gleixner tglx@linutronix.de Link: http://lkml.kernel.org/r/154998807741.31052.11229157537816341591.stgit@devbo... Signed-off-by: Ingo Molnar mingo@kernel.org Signed-off-by: Sasha Levin sashal@kernel.org --- kernel/rcu/update.c | 2 ++ 1 file changed, 2 insertions(+)
diff --git a/kernel/rcu/update.c b/kernel/rcu/update.c index 39cb23d22109..81688a133552 100644 --- a/kernel/rcu/update.c +++ b/kernel/rcu/update.c @@ -52,6 +52,7 @@ #include <linux/tick.h> #include <linux/rcupdate_wait.h> #include <linux/sched/isolation.h> +#include <linux/kprobes.h>
#define CREATE_TRACE_POINTS
@@ -253,6 +254,7 @@ int notrace debug_lockdep_rcu_enabled(void) current->lockdep_recursion == 0; } EXPORT_SYMBOL_GPL(debug_lockdep_rcu_enabled); +NOKPROBE_SYMBOL(debug_lockdep_rcu_enabled);
/** * rcu_read_lock_held() - might we be in RCU read-side critical section?