From 903649e718f80da2ba4b65a0adf6930219b4b2e5 Mon Sep 17 00:00:00 2001 From: Michael Chan Date: Mon, 28 Aug 2017 13:40:30 -0400 Subject: [PATCH] bnxt_en: Improve -ENOMEM logic in NAPI poll loop. If we cannot allocate RX buffers in the NAPI poll loop when processing an RX event, the current code does not count that event towards the NAPI budget. This can cause us to potentially loop forever in NAPI if we consistently cannot allocate new buffers. Improve it by counting -ENOMEM event as 1 towards the NAPI budget. Cc: Martin KaFai Lau Signed-off-by: Michael Chan Reported-by: Martin KaFai Lau Acked-by: Martin KaFai Lau Signed-off-by: David S. Miller --- drivers/net/ethernet/broadcom/bnxt/bnxt.c | 7 +++++++ 1 file changed, 7 insertions(+) diff --git a/drivers/net/ethernet/broadcom/bnxt/bnxt.c b/drivers/net/ethernet/broadcom/bnxt/bnxt.c index 1afb408798d1..a34fcddbd14c 100644 --- a/drivers/net/ethernet/broadcom/bnxt/bnxt.c +++ b/drivers/net/ethernet/broadcom/bnxt/bnxt.c @@ -1850,6 +1850,13 @@ static int bnxt_poll_work(struct bnxt *bp, struct bnxt_napi *bnapi, int budget) &event); if (likely(rc >= 0)) rx_pkts += rc; + /* Increment rx_pkts when rc is -ENOMEM to count towards + * the NAPI budget. Otherwise, we may potentially loop + * here forever if we consistently cannot allocate + * buffers. + */ + else if (rc == -ENOMEM) + rx_pkts++; else if (rc == -EBUSY) /* partial completion */ break; } else if (unlikely((TX_CMP_TYPE(txcmp) == -- 2.39.5