From 66fbb541a5d2d58fdae21c1e7b558a75bfbd483f Mon Sep 17 00:00:00 2001
From: Oliver Neukum <oneukum@suse.de>
Date: Thu, 15 Nov 2007 09:31:10 +0800
Subject: [PATCH] iwl4965: fix not correctly dealing with hotunplug

The interrupt handler returns IRQ_NONE if it detects that the device
is gone. That's incorrect because the device may have raised the interrupt.
Not acknowledging it may trigger the spurious interrupt detection and kill
drivers sharing the interrupt line.

Signed-off-by: Oliver Neukum <oneukum@suse.de>
Signed-off-by: Zhu Yi <yi.zhu@intel.com>
Signed-off-by: John W. Linville <linville@tuxdriver.com>
---
 drivers/net/wireless/iwlwifi/iwl4965-base.c | 8 +++++---
 1 file changed, 5 insertions(+), 3 deletions(-)

diff --git a/drivers/net/wireless/iwlwifi/iwl4965-base.c b/drivers/net/wireless/iwlwifi/iwl4965-base.c
index d60adcb9bd4a..d5107bb413cd 100644
--- a/drivers/net/wireless/iwlwifi/iwl4965-base.c
+++ b/drivers/net/wireless/iwlwifi/iwl4965-base.c
@@ -5156,9 +5156,10 @@ static irqreturn_t iwl_isr(int irq, void *data)
 	}
 
 	if ((inta == 0xFFFFFFFF) || ((inta & 0xFFFFFFF0) == 0xa5a5a5a0)) {
-		/* Hardware disappeared */
+		/* Hardware disappeared. It might have already raised
+		 * an interrupt */
 		IWL_WARNING("HARDWARE GONE?? INTA == 0x%080x\n", inta);
-		goto none;
+		goto unplugged;
 	}
 
 	IWL_DEBUG_ISR("ISR inta 0x%08x, enabled 0x%08x, fh 0x%08x\n",
@@ -5166,8 +5167,9 @@ static irqreturn_t iwl_isr(int irq, void *data)
 
 	/* iwl_irq_tasklet() will service interrupts and re-enable them */
 	tasklet_schedule(&priv->irq_tasklet);
-	spin_unlock(&priv->lock);
 
+ unplugged:
+	spin_unlock(&priv->lock);
 	return IRQ_HANDLED;
 
  none:
-- 
GitLab