diff options
| author | Peter Zijlstra <peterz@infradead.org> | 2020-10-02 11:04:21 +0200 |
|---|---|---|
| committer | Ingo Molnar <mingo@kernel.org> | 2020-10-09 08:53:30 +0200 |
| commit | 4d004099a668c41522242aa146a38cc4eb59cb1e (patch) | |
| tree | 9a8023c8fdbe431b9edbbcb2621dbf5c6bb4367b /include/linux/lockdep.h | |
| parent | 2bb8945bcc1a768f2bc402a16c9610bba8d5187d (diff) | |
lockdep: Fix lockdep recursion
Steve reported that lockdep_assert*irq*(), when nested inside lockdep
itself, will trigger a false-positive.
One example is the stack-trace code, as called from inside lockdep,
triggering tracing, which in turn calls RCU, which then uses
lockdep_assert_irqs_disabled().
Fixes: a21ee6055c30 ("lockdep: Change hardirq{s_enabled,_context} to per-cpu variables")
Reported-by: Steven Rostedt <rostedt@goodmis.org>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Diffstat (limited to 'include/linux/lockdep.h')
| -rw-r--r-- | include/linux/lockdep.h | 13 |
1 files changed, 8 insertions, 5 deletions
diff --git a/include/linux/lockdep.h b/include/linux/lockdep.h index 6a584b3e5c74..b1227be47496 100644 --- a/include/linux/lockdep.h +++ b/include/linux/lockdep.h @@ -534,6 +534,7 @@ do { \ DECLARE_PER_CPU(int, hardirqs_enabled); DECLARE_PER_CPU(int, hardirq_context); +DECLARE_PER_CPU(unsigned int, lockdep_recursion); /* * The below lockdep_assert_*() macros use raw_cpu_read() to access the above @@ -543,25 +544,27 @@ DECLARE_PER_CPU(int, hardirq_context); * read the value from our previous CPU. */ +#define __lockdep_enabled (debug_locks && !raw_cpu_read(lockdep_recursion)) + #define lockdep_assert_irqs_enabled() \ do { \ - WARN_ON_ONCE(debug_locks && !raw_cpu_read(hardirqs_enabled)); \ + WARN_ON_ONCE(__lockdep_enabled && !raw_cpu_read(hardirqs_enabled)); \ } while (0) #define lockdep_assert_irqs_disabled() \ do { \ - WARN_ON_ONCE(debug_locks && raw_cpu_read(hardirqs_enabled)); \ + WARN_ON_ONCE(__lockdep_enabled && raw_cpu_read(hardirqs_enabled)); \ } while (0) #define lockdep_assert_in_irq() \ do { \ - WARN_ON_ONCE(debug_locks && !raw_cpu_read(hardirq_context)); \ + WARN_ON_ONCE(__lockdep_enabled && !raw_cpu_read(hardirq_context)); \ } while (0) #define lockdep_assert_preemption_enabled() \ do { \ WARN_ON_ONCE(IS_ENABLED(CONFIG_PREEMPT_COUNT) && \ - debug_locks && \ + __lockdep_enabled && \ (preempt_count() != 0 || \ !raw_cpu_read(hardirqs_enabled))); \ } while (0) @@ -569,7 +572,7 @@ do { \ #define lockdep_assert_preemption_disabled() \ do { \ WARN_ON_ONCE(IS_ENABLED(CONFIG_PREEMPT_COUNT) && \ - debug_locks && \ + __lockdep_enabled && \ (preempt_count() == 0 && \ raw_cpu_read(hardirqs_enabled))); \ } while (0) |