[patch 108/149] via-velocity: Give RX descriptors to the NIC later on open or MTU change

From: Greg KH
Date: Thu Jul 01 2010 - 14:34:28 EST


2.6.32-stable review patch. If anyone has any objections, please let us know.

------------------

From: Ben Hutchings <ben@xxxxxxxxxxxxxxx>

commit 35bb5cadc8c7b1462df57e32e08d964f1be7a75c upstream.

velocity_open() calls velocity_give_many_rx_descs(), which gives RX
descriptors to the NIC, before installing an interrupt handler or
calling velocity_init_registers(). I think this is very unsafe and it
appears to explain the bug report <http://bugs.debian.org/508527>.

On MTU change, velocity_give_many_rx_descs() is again called before
velocity_init_registers(). I'm not sure whether this is unsafe but
it does look wrong.

Therefore, move the calls to velocity_give_many_rx_descs() after
request_irq() and velocity_init_registers().

Signed-off-by: Ben Hutchings <ben@xxxxxxxxxxxxxxx>
Tested-by: Jan Ceuleers <jan.ceuleers@xxxxxxxxxxxx>
Signed-off-by: David S. Miller <davem@xxxxxxxxxxxxx>
Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxx>

---
drivers/net/via-velocity.c | 8 ++++----
1 file changed, 4 insertions(+), 4 deletions(-)

--- a/drivers/net/via-velocity.c
+++ b/drivers/net/via-velocity.c
@@ -2186,8 +2186,6 @@ static int velocity_open(struct net_devi
/* Ensure chip is running */
pci_set_power_state(vptr->pdev, PCI_D0);

- velocity_give_many_rx_descs(vptr);
-
velocity_init_registers(vptr, VELOCITY_INIT_COLD);

ret = request_irq(vptr->pdev->irq, &velocity_intr, IRQF_SHARED,
@@ -2199,6 +2197,8 @@ static int velocity_open(struct net_devi
goto out;
}

+ velocity_give_many_rx_descs(vptr);
+
mac_enable_int(vptr->mac_regs);
netif_start_queue(dev);
vptr->flags |= VELOCITY_FLAGS_OPENED;
@@ -2287,10 +2287,10 @@ static int velocity_change_mtu(struct ne

dev->mtu = new_mtu;

- velocity_give_many_rx_descs(vptr);
-
velocity_init_registers(vptr, VELOCITY_INIT_COLD);

+ velocity_give_many_rx_descs(vptr);
+
mac_enable_int(vptr->mac_regs);
netif_start_queue(dev);



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