From 2f70de5b98e58d48ccf37198395c5f47b4cf89a0 Mon Sep 17 00:00:00 2001 From: Juergen Gross Date: Thu, 11 Feb 2021 11:16:12 +0100 Subject: [PATCH] xen/netback: fix spurious event detection for common event case [ Upstream commit a3daf3d39132b405781be8d9ede0c449b244b64e ] In case of a common event for rx and tx queue the event should be regarded to be spurious if no rx and no tx requests are pending. Unfortunately the condition for testing that is wrong causing to decide a event being spurious if no rx OR no tx requests are pending. Fix that plus using local variables for rx/tx pending indicators in order to split function calls and if condition. Fixes: 23025393dbeb3b ("xen/netback: use lateeoi irq binding") Signed-off-by: Juergen Gross Reviewed-by: Jan Beulich Reviewed-by: Paul Durrant Reviewed-by: Wei Liu Signed-off-by: David S. Miller Signed-off-by: Sasha Levin --- drivers/net/xen-netback/interface.c | 8 +++++--- 1 file changed, 5 insertions(+), 3 deletions(-) diff --git a/drivers/net/xen-netback/interface.c b/drivers/net/xen-netback/interface.c index e61073c75142..d9d06dc689ed 100644 --- a/drivers/net/xen-netback/interface.c +++ b/drivers/net/xen-netback/interface.c @@ -161,13 +161,15 @@ irqreturn_t xenvif_interrupt(int irq, void *dev_id) { struct xenvif_queue *queue = dev_id; int old; + bool has_rx, has_tx; old = atomic_fetch_or(NETBK_COMMON_EOI, &queue->eoi_pending); WARN(old, "Interrupt while EOI pending\n"); - /* Use bitwise or as we need to call both functions. */ - if ((!xenvif_handle_tx_interrupt(queue) | - !xenvif_handle_rx_interrupt(queue))) { + has_tx = xenvif_handle_tx_interrupt(queue); + has_rx = xenvif_handle_rx_interrupt(queue); + + if (!has_rx && !has_tx) { atomic_andnot(NETBK_COMMON_EOI, &queue->eoi_pending); xen_irq_lateeoi(irq, XEN_EOI_FLAG_SPURIOUS); }