diff options
| author | Greg Rose <gregory.v.rose@intel.com> | 2012-01-18 23:13:31 +0100 |
|---|---|---|
| committer | David S. Miller <davem@davemloft.net> | 2012-01-19 18:35:06 +0100 |
| commit | 375b27cf5db963e2bc2a34dc5643d0d7ceca1ee2 (patch) | |
| tree | 5448047154a5c4676685f8665d8af6b96647d68b /drivers | |
| parent | ixgbe: Fix register defines to correctly handle complex expressions (diff) | |
| download | linux-375b27cf5db963e2bc2a34dc5643d0d7ceca1ee2.tar.xz linux-375b27cf5db963e2bc2a34dc5643d0d7ceca1ee2.zip | |
ixgbevf: Prevent possible race condition by checking for message
The mailbox interrupt routine might cause a race condition sometimes
and cause a message to be missed.
Signed-off-by: Greg Rose <gregory.v.rose@intel.com>
Tested-by: Sibai Li <sibai.li@intel.com>
Signed-off-by: Jeff Kirsher <jeffrey.t.kirsher@intel.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Diffstat (limited to 'drivers')
| -rw-r--r-- | drivers/net/ethernet/intel/ixgbevf/ixgbevf_main.c | 39 |
1 files changed, 21 insertions, 18 deletions
diff --git a/drivers/net/ethernet/intel/ixgbevf/ixgbevf_main.c b/drivers/net/ethernet/intel/ixgbevf/ixgbevf_main.c index 891162d1610c..1cad3b6d2c30 100644 --- a/drivers/net/ethernet/intel/ixgbevf/ixgbevf_main.c +++ b/drivers/net/ethernet/intel/ixgbevf/ixgbevf_main.c @@ -917,31 +917,34 @@ static irqreturn_t ixgbevf_msix_mbx(int irq, void *data) struct ixgbe_hw *hw = &adapter->hw; u32 eicr; u32 msg; + bool got_ack = false; eicr = IXGBE_READ_REG(hw, IXGBE_VTEICS); IXGBE_WRITE_REG(hw, IXGBE_VTEICR, eicr); - if (!hw->mbx.ops.check_for_ack(hw)) { - /* - * checking for the ack clears the PFACK bit. Place - * it back in the v2p_mailbox cache so that anyone - * polling for an ack will not miss it. Also - * avoid the read below because the code to read - * the mailbox will also clear the ack bit. This was - * causing lost acks. Just cache the bit and exit - * the IRQ handler. - */ - hw->mbx.v2p_mailbox |= IXGBE_VFMAILBOX_PFACK; - goto out; - } + if (!hw->mbx.ops.check_for_ack(hw)) + got_ack = true; - /* Not an ack interrupt, go ahead and read the message */ - hw->mbx.ops.read(hw, &msg, 1); + if (!hw->mbx.ops.check_for_msg(hw)) { + hw->mbx.ops.read(hw, &msg, 1); - if ((msg & IXGBE_MBVFICR_VFREQ_MASK) == IXGBE_PF_CONTROL_MSG) - mod_timer(&adapter->watchdog_timer, - round_jiffies(jiffies + 1)); + if ((msg & IXGBE_MBVFICR_VFREQ_MASK) == IXGBE_PF_CONTROL_MSG) + mod_timer(&adapter->watchdog_timer, + round_jiffies(jiffies + 1)); + if (msg & IXGBE_VT_MSGTYPE_NACK) + pr_warn("Last Request of type %2.2x to PF Nacked\n", + msg & 0xFF); + goto out; + } + + /* + * checking for the ack clears the PFACK bit. Place + * it back in the v2p_mailbox cache so that anyone + * polling for an ack will not miss it + */ + if (got_ack) + hw->mbx.v2p_mailbox |= IXGBE_VFMAILBOX_PFACK; out: return IRQ_HANDLED; } |