# This is a BitKeeper generated patch for the following project:
# Project Name: Linux kernel tree
# This patch format is intended for GNU patch command version 2.5 or higher.
# This patch includes the following deltas:
#	           ChangeSet	1.1102  -> 1.1103 
#	arch/i386/kernel/irq.c	1.7     -> 1.8    
#	include/asm-i386/hardirq.h	1.4     -> 1.5    
#
# The following is the BitKeeper ChangeSet Log
# --------------------------------------------
# 03/08/24	tj@atj.dyndns.org	1.1103
# - irq/bh race fixes.
# --------------------------------------------
#
diff -Nru a/arch/i386/kernel/irq.c b/arch/i386/kernel/irq.c
--- a/arch/i386/kernel/irq.c	Sun Aug 24 12:18:01 2003
+++ b/arch/i386/kernel/irq.c	Sun Aug 24 12:18:01 2003
@@ -272,8 +272,7 @@
 		 * already executing in one..
 		 */
 		if (!irqs_running())
-			if (local_bh_count(cpu) || !spin_is_locked(&global_bh_lock))
-				break;
+			break;
 
 		/* Duh, we have to loop. Release the lock to avoid deadlocks */
 		clear_bit(0,&global_irq_lock);
@@ -307,6 +306,7 @@
  */
 void synchronize_irq(void)
 {
+	smp_mb(); /* Sync with irq_enter() */
 	if (irqs_running()) {
 		/* Stupid approach */
 		cli();
@@ -332,6 +332,10 @@
 	 * in an interrupt context. 
 	 */
 	wait_on_irq(cpu);
+
+	/* bh is disallowed inside irqlock. */
+	if (!local_bh_count(cpu))
+		spin_lock(&global_bh_lock);
 
 	/*
 	 * Ok, finally..
diff -Nru a/include/asm-i386/hardirq.h b/include/asm-i386/hardirq.h
--- a/include/asm-i386/hardirq.h	Sun Aug 24 12:18:01 2003
+++ b/include/asm-i386/hardirq.h	Sun Aug 24 12:18:01 2003
@@ -54,10 +54,15 @@
 	return 0;
 }
 
+extern spinlock_t global_bh_lock; /* copied from linux/interrupt.h to break
+				     include loop :-( */
+
 static inline void release_irqlock(int cpu)
 {
 	/* if we didn't own the irq lock, just ignore.. */
 	if (global_irq_holder == (unsigned char) cpu) {
+		if (!local_bh_count(cpu))
+			spin_unlock(&global_bh_lock);
 		global_irq_holder = NO_PROC_ID;
 		clear_bit(0,&global_irq_lock);
 	}
@@ -66,6 +71,8 @@
 static inline void irq_enter(int cpu, int irq)
 {
 	++local_irq_count(cpu);
+
+	smp_mb(); /* sync with wait_on_irq() and synchronize_irq() */
 
 	while (test_bit(0,&global_irq_lock)) {
 		cpu_relax();