net/sfc/base: ensure EvQ poll stops when abort is requested

If an event handler requested an abort, only the inner loop was
guaranteed to be broken out of - the outer loop could continue
if total == batch.

Fix this by poisoning batch to ensure it is different to total.

Signed-off-by: Mark Spender <mspender@solarflare.com>
Signed-off-by: Andrew Rybchenko <arybchenko@solarflare.com>

diff --git a/drivers/net/sfc/base/efx_ev.c b/drivers/net/sfc/base/efx_ev.c
index 1139cc2..907c424 100644 (file)
--- a/drivers/net/sfc/base/efx_ev.c
+++ b/drivers/net/sfc/base/efx_ev.c
@@ -480,6 +480,14 @@ efx_ev_qpoll(
                        if (should_abort) {
                                /* Ignore subsequent events */
                                total = index + 1;
+
+                               /*
+                                * Poison batch to ensure the outer
+                                * loop is broken out of.
+                                */
+                               EFSYS_ASSERT(batch <= EFX_EV_BATCH);
+                               batch += (EFX_EV_BATCH << 1);
+                               EFSYS_ASSERT(total != batch);
                                break;
                        }
                }