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Subject[PATCH RT 2/2] x86: lazy-preempt: properly check against preempt-mask
should_resched() should check against preempt_offset after unmasking the
need-resched-bit. Otherwise should_resched() won't work for
preempt_offset != 0 and lazy-preempt set.

Cc: stable-rt@vger.kernel.org
Signed-off-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
---
arch/x86/include/asm/preempt.h | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/arch/x86/include/asm/preempt.h b/arch/x86/include/asm/preempt.h
index 22992c8377952..f667087792747 100644
--- a/arch/x86/include/asm/preempt.h
+++ b/arch/x86/include/asm/preempt.h
@@ -118,7 +118,7 @@ static __always_inline bool should_resched(int preempt_offset)

/* preempt count == 0 ? */
tmp &= ~PREEMPT_NEED_RESCHED;
- if (tmp)
+ if (tmp != preempt_offset)
return false;
if (current_thread_info()->preempt_lazy_count)
return false;
--
2.20.1
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