From d7618e38461e6a3f190d88fb941befd51b7c29b0 Mon Sep 17 00:00:00 2001 From: Benjamin Poirier Date: Fri, 27 Sep 2019 19:11:55 +0900 Subject: [PATCH] staging: qlge: Fix irq masking in INTx mode Tracing the driver operation reveals that the INTR_EN_EN bit (per-queue interrupt control) does not immediately prevent rx completion interrupts when the device is operating in INTx mode. This leads to interrupts being raised while napi is scheduled/running. Those interrupts are ignored by qlge_isr() and falsely reported as IRQ_NONE thanks to the irq_cnt scheme. This in turn can cause frames to loiter in the receive queue until a later frame leads to another rx interrupt that will schedule napi. Use the INTR_EN_EI bit (master interrupt control) instead. Signed-off-by: Benjamin Poirier Link: https://lore.kernel.org/r/20190927101210.23856-2-bpoirier@suse.com Signed-off-by: Greg Kroah-Hartman --- drivers/staging/qlge/qlge_main.c | 11 +++++++++++ 1 file changed, 11 insertions(+) diff --git a/drivers/staging/qlge/qlge_main.c b/drivers/staging/qlge/qlge_main.c index 6cae330..d7b64d3 100644 --- a/drivers/staging/qlge/qlge_main.c +++ b/drivers/staging/qlge/qlge_main.c @@ -3366,6 +3366,7 @@ msi: } } qlge_irq_type = LEG_IRQ; + set_bit(QL_LEGACY_ENABLED, &qdev->flags); netif_printk(qdev, ifup, KERN_DEBUG, qdev->ndev, "Running with legacy interrupts.\n"); } @@ -3509,6 +3510,16 @@ static void ql_resolve_queues_to_irqs(struct ql_adapter *qdev) intr_context->intr_dis_mask = INTR_EN_TYPE_MASK | INTR_EN_INTR_MASK | INTR_EN_TYPE_DISABLE; + if (test_bit(QL_LEGACY_ENABLED, &qdev->flags)) { + /* Experience shows that when using INTx interrupts, + * the device does not always auto-mask INTR_EN_EN. + * Moreover, masking INTR_EN_EN manually does not + * immediately prevent interrupt generation. + */ + intr_context->intr_en_mask |= INTR_EN_EI << 16 | + INTR_EN_EI; + intr_context->intr_dis_mask |= INTR_EN_EI << 16; + } intr_context->intr_read_mask = INTR_EN_TYPE_MASK | INTR_EN_INTR_MASK | INTR_EN_TYPE_READ; /* -- 2.7.4