Re: [PATCH]skge napi->poll() locking bug

From: Jeff Garzik
Date: Tue Mar 25 2008 - 23:21:02 EST


Marin Mitov wrote:
Hi all,

According to: Documentation/networking/netdevices.txt:

<cite>
napi->poll:
..........
Context: softirq
will be called with interrupts disabled by netconsole.
</cite>

napi->poll() could be called either with interrupts enabled (in softirq context) or disabled (by netconsole), so the irq flag
should be preserved.

Inspired by Ingo's resent forcedeth patch :-)

Regards

Marin Mitov

Signed-off-by: Marin Mitov <mitov@xxxxxxxxxxx>
===============================
--- a/drivers/net/skge.c 2008-03-23 09:06:13.000000000 +0200
+++ b/drivers/net/skge.c 2008-03-23 09:24:47.000000000 +0200
@@ -3199,12 +3199,14 @@ static int skge_poll(struct napi_struct skge_write8(hw, Q_ADDR(rxqaddr[skge->port], Q_CSR), CSR_START);
if (work_done < to_do) {
- spin_lock_irq(&hw->hw_lock);
+ unsigned long flags;
+
+ spin_lock_irqsave(&hw->hw_lock, flags);
__netif_rx_complete(dev, napi);
hw->intr_mask |= napimask[skge->port];
skge_write32(hw, B0_IMSK, hw->intr_mask);
skge_read32(hw, B0_IMSK);
- spin_unlock_irq(&hw->hw_lock);
+ spin_unlock_irqrestore(&hw->hw_lock, flags);
}
return work_done;


--

applied


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