From: Peter Zijlstra <pet...@infradead.org> [ Upstream commit f8e48a3dca060e80f672d398d181db1298fbc86c ]
It is valid (albeit uncommon) to call local_irq_enable() without first having called local_irq_disable(). In this case we enter lockdep_hardirqs_on*() with IRQs enabled and trip a preemption warning for using __this_cpu_read(). Use this_cpu_read() instead to avoid the warning. Fixes: 4d004099a6 ("lockdep: Fix lockdep recursion") Reported-by: syzbot+53f8ce8bbc07924b6...@syzkaller.appspotmail.com Reported-by: kernel test robot <l...@intel.com> Signed-off-by: Peter Zijlstra (Intel) <pet...@infradead.org> Signed-off-by: Sasha Levin <sas...@kernel.org> --- kernel/locking/lockdep.c | 4 ++-- 1 file changed, 2 insertions(+), 2 deletions(-) diff --git a/kernel/locking/lockdep.c b/kernel/locking/lockdep.c index 85d15f0362dc5..3eb35ad1b5241 100644 --- a/kernel/locking/lockdep.c +++ b/kernel/locking/lockdep.c @@ -3681,7 +3681,7 @@ void lockdep_hardirqs_on_prepare(unsigned long ip) if (unlikely(in_nmi())) return; - if (unlikely(__this_cpu_read(lockdep_recursion))) + if (unlikely(this_cpu_read(lockdep_recursion))) return; if (unlikely(lockdep_hardirqs_enabled())) { @@ -3750,7 +3750,7 @@ void noinstr lockdep_hardirqs_on(unsigned long ip) goto skip_checks; } - if (unlikely(__this_cpu_read(lockdep_recursion))) + if (unlikely(this_cpu_read(lockdep_recursion))) return; if (lockdep_hardirqs_enabled()) { -- 2.27.0