From 6f535763165331bb91277d7519b507fed22034e5 Mon Sep 17 00:00:00 2001 From: "David S. Miller" Date: Thu, 11 Oct 2007 18:08:29 -0700 Subject: [NET]: Fix NAPI completion handling in some drivers. In order for the list handling in net_rx_action() to be correct, drivers must follow certain rules as stated by this comment in net_rx_action(): /* Drivers must not modify the NAPI state if they * consume the entire weight. In such cases this code * still "owns" the NAPI instance and therefore can * move the instance around on the list at-will. */ A few drivers do not do this because they mix the budget checks with reading hardware state, resulting in crashes like the one reported by takano@axe-inc.co.jp. BNX2 and TG3 are taken care of here, SKY2 fix is from Stephen Hemminger. Signed-off-by: David S. Miller --- drivers/net/bnx2.c | 52 ++++++++++++++++++++++++++++++++-------------------- 1 file changed, 32 insertions(+), 20 deletions(-) (limited to 'drivers/net/bnx2.c') diff --git a/drivers/net/bnx2.c b/drivers/net/bnx2.c index bbfbdafb4ae5..d68accea380b 100644 --- a/drivers/net/bnx2.c +++ b/drivers/net/bnx2.c @@ -2633,15 +2633,11 @@ bnx2_has_work(struct bnx2 *bp) return 0; } -static int -bnx2_poll(struct napi_struct *napi, int budget) +static int bnx2_poll_work(struct bnx2 *bp, int work_done, int budget) { - struct bnx2 *bp = container_of(napi, struct bnx2, napi); - struct net_device *dev = bp->dev; struct status_block *sblk = bp->status_blk; u32 status_attn_bits = sblk->status_attn_bits; u32 status_attn_bits_ack = sblk->status_attn_bits_ack; - int work_done = 0; if ((status_attn_bits & STATUS_ATTN_EVENTS) != (status_attn_bits_ack & STATUS_ATTN_EVENTS)) { @@ -2660,27 +2656,43 @@ bnx2_poll(struct napi_struct *napi, int budget) bnx2_tx_int(bp); if (bp->status_blk->status_rx_quick_consumer_index0 != bp->hw_rx_cons) - work_done = bnx2_rx_int(bp, budget); + work_done += bnx2_rx_int(bp, budget - work_done); - bp->last_status_idx = bp->status_blk->status_idx; - rmb(); + return work_done; +} + +static int bnx2_poll(struct napi_struct *napi, int budget) +{ + struct bnx2 *bp = container_of(napi, struct bnx2, napi); + int work_done = 0; + + while (1) { + work_done = bnx2_poll_work(bp, work_done, budget); - if (!bnx2_has_work(bp)) { - netif_rx_complete(dev, napi); - if (likely(bp->flags & USING_MSI_FLAG)) { + if (unlikely(work_done >= budget)) + break; + + if (likely(!bnx2_has_work(bp))) { + bp->last_status_idx = bp->status_blk->status_idx; + rmb(); + + netif_rx_complete(bp->dev, napi); + if (likely(bp->flags & USING_MSI_FLAG)) { + REG_WR(bp, BNX2_PCICFG_INT_ACK_CMD, + BNX2_PCICFG_INT_ACK_CMD_INDEX_VALID | + bp->last_status_idx); + return 0; + } REG_WR(bp, BNX2_PCICFG_INT_ACK_CMD, BNX2_PCICFG_INT_ACK_CMD_INDEX_VALID | + BNX2_PCICFG_INT_ACK_CMD_MASK_INT | bp->last_status_idx); - return 0; - } - REG_WR(bp, BNX2_PCICFG_INT_ACK_CMD, - BNX2_PCICFG_INT_ACK_CMD_INDEX_VALID | - BNX2_PCICFG_INT_ACK_CMD_MASK_INT | - bp->last_status_idx); - REG_WR(bp, BNX2_PCICFG_INT_ACK_CMD, - BNX2_PCICFG_INT_ACK_CMD_INDEX_VALID | - bp->last_status_idx); + REG_WR(bp, BNX2_PCICFG_INT_ACK_CMD, + BNX2_PCICFG_INT_ACK_CMD_INDEX_VALID | + bp->last_status_idx); + break; + } } return work_done; -- cgit v1.2.3