D57782.diff
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	diff --git a/sys/compat/linuxkpi/common/include/linux/hardirq.h b/sys/compat/linuxkpi/common/include/linux/hardirq.h
	--- a/sys/compat/linuxkpi/common/include/linux/hardirq.h
	+++ b/sys/compat/linuxkpi/common/include/linux/hardirq.h
	@@ -49,4 +49,26 @@
	*/
	#define synchronize_hardirq(irq) _intr_drain((irq))

	+/*
	+ * irqs_disabled - returns true if the caller should not sleep
	+ *
	+ * On Linux, irqs_disabled() reflects hardware IRQ masking (EFLAGS.IF on x86).
	+ * FreeBSD does not disable hardware IRQs for linuxkpi spinlocks; instead:
	+ *
	+ * - spin_lock() calls local_bh_disable() -> sched_pin() -> td_pinned++
	+ * td_pinned > 0 therefore means a linuxkpi spinlock is held, which is
	+ * the context where Linux irqs_disabled() would have returned true.
	+ *
	+ * - td_critnest > 0 indicates a critical section (critical_enter() or
	+ * an MTX_SPIN mutex), where sleeping is equally forbidden.
	+ *
	+ * Together these cover the cases where callers must spin with cpu_relax()
	+ * rather than sleeping.
	+ */
	+static inline bool
	+irqs_disabled(void)
	+{
	+ return (curthread->td_pinned > 0 \|\| curthread->td_critnest > 0);
	+}
	+
	#endif /* _LINUXKPI_LINUX_HARDIRQ_H_ */