From 30bb0e0dce78427f3e5cb728d6b5ea73acbefffa Mon Sep 17 00:00:00 2001
From: Jeff Kirsher <jeffrey.t.kirsher@intel.com>
Date: Thu, 11 Dec 2008 21:28:11 -0800
Subject: [PATCH] e1000e: fix double release of mutex

During a reset, releasing the swflag after it failed to be acquired would
cause a double unlock of the mutex.  Instead, test whether acquisition of
the swflag was successful and if not, do not release the swflag.  The reset
must still be done to bring the device to a quiescent state.

This resolves [BUG 12200] BUG: bad unlock balance detected! e1000e
http://bugzilla.kernel.org/show_bug.cgi?id=12200

Signed-off-by: Jeff Kirsher <jeffrey.t.kirsher@intel.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
---
 drivers/net/e1000e/ich8lan.c | 9 +++++++--
 1 file changed, 7 insertions(+), 2 deletions(-)

diff --git a/drivers/net/e1000e/ich8lan.c b/drivers/net/e1000e/ich8lan.c
index 523b9716a543..d115a6d30f29 100644
--- a/drivers/net/e1000e/ich8lan.c
+++ b/drivers/net/e1000e/ich8lan.c
@@ -1893,12 +1893,17 @@ static s32 e1000_reset_hw_ich8lan(struct e1000_hw *hw)
 		ctrl |= E1000_CTRL_PHY_RST;
 	}
 	ret_val = e1000_acquire_swflag_ich8lan(hw);
+	/* Whether or not the swflag was acquired, we need to reset the part */
 	hw_dbg(hw, "Issuing a global reset to ich8lan");
 	ew32(CTRL, (ctrl | E1000_CTRL_RST));
 	msleep(20);
 
-	/* release the swflag because it is not reset by hardware reset */
-	e1000_release_swflag_ich8lan(hw);
+	if (!ret_val) {
+		/* release the swflag because it is not reset by
+		 * hardware reset
+		 */
+		e1000_release_swflag_ich8lan(hw);
+	}
 
 	ret_val = e1000e_get_auto_rd_done(hw);
 	if (ret_val) {
-- 
2.34.1