Merge branch 'tg3-net'

Prashant Sreedharan says:

====================
tg3: synchronize_irq() should be called without taking locks

v2: Added Reported-by, Tested-by fields and reference to the thread that
    reported the problem

This series addresses the problem reported by Peter Hurley in mail thread
https://lkml.org/lkml/2015/1/12/1082
====================
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

drivers/net/ethernet/broadcom/tg3.c

@@ -7413,6 +7413,8 @@ static inline void tg3_netif_start(struct tg3 *tp)
 }
 
 static void tg3_irq_quiesce(struct tg3 *tp)
+	__releases(tp->lock)
+	__acquires(tp->lock)
 {
 	int i;
 
@@ -7421,8 +7423,12 @@ static void tg3_irq_quiesce(struct tg3 *tp)
 	tp->irq_sync = 1;
 	smp_mb();
 
+	spin_unlock_bh(&tp->lock);
+
 	for (i = 0; i < tp->irq_cnt; i++)
 		synchronize_irq(tp->napi[i].irq_vec);
+
+	spin_lock_bh(&tp->lock);
 }
 
 /* Fully shutdown all tg3 driver activity elsewhere in the system.
@@ -9018,6 +9024,8 @@ static void tg3_restore_clk(struct tg3 *tp)
 
 /* tp->lock is held. */
 static int tg3_chip_reset(struct tg3 *tp)
+	__releases(tp->lock)
+	__acquires(tp->lock)
 {
 	u32 val;
 	void (*write_op)(struct tg3 *, u32, u32);
@@ -9073,9 +9081,13 @@ static int tg3_chip_reset(struct tg3 *tp)
 	}
 	smp_mb();
 
+	tg3_full_unlock(tp);
+
 	for (i = 0; i < tp->irq_cnt; i++)
 		synchronize_irq(tp->napi[i].irq_vec);
 
+	tg3_full_lock(tp, 0);
+
 	if (tg3_asic_rev(tp) == ASIC_REV_57780) {
 		val = tr32(TG3_PCIE_LNKCTL) & ~TG3_PCIE_LNKCTL_L1_PLL_PD_EN;
 		tw32(TG3_PCIE_LNKCTL, val | TG3_PCIE_LNKCTL_L1_PLL_PD_DIS);
@@ -10903,11 +10915,13 @@ static void tg3_timer(unsigned long __opaque)
 {
 	struct tg3 *tp = (struct tg3 *) __opaque;
 
-	if (tp->irq_sync || tg3_flag(tp, RESET_TASK_PENDING))
-		goto restart_timer;
-
 	spin_lock(&tp->lock);
 
+	if (tp->irq_sync || tg3_flag(tp, RESET_TASK_PENDING)) {
+		spin_unlock(&tp->lock);
+		goto restart_timer;
+	}
+
 	if (tg3_asic_rev(tp) == ASIC_REV_5717 ||
 	    tg3_flag(tp, 57765_CLASS))
 		tg3_chk_missed_msi(tp);
@@ -11101,11 +11115,13 @@ static void tg3_reset_task(struct work_struct *work)
 	struct tg3 *tp = container_of(work, struct tg3, reset_task);
 	int err;
 
+	rtnl_lock();
 	tg3_full_lock(tp, 0);
 
 	if (!netif_running(tp->dev)) {
 		tg3_flag_clear(tp, RESET_TASK_PENDING);
 		tg3_full_unlock(tp);
+		rtnl_unlock();
 		return;
 	}
 
@@ -11138,6 +11154,7 @@ static void tg3_reset_task(struct work_struct *work)
 		tg3_phy_start(tp);
 
 	tg3_flag_clear(tp, RESET_TASK_PENDING);
+	rtnl_unlock();
 }
 
 static int tg3_request_irq(struct tg3 *tp, int irq_num)