do better accounting of how many msix interrupts we want to use.

ok jmatthew@

diff --git a/sys/dev/pci/if_mcx.c b/sys/dev/pci/if_mcx.c
index 72fba2f..8d5c886 100644 (file)
--- a/sys/dev/pci/if_mcx.c
+++ b/sys/dev/pci/if_mcx.c
@@ -1,4 +1,4 @@
-/*     $OpenBSD: if_mcx.c,v 1.97 2021/01/25 12:27:42 dlg Exp $ */
+/*     $OpenBSD: if_mcx.c,v 1.98 2021/01/27 07:46:11 dlg Exp $ */
 
 /*
  * Copyright (c) 2017 David Gwynne <dlg@openbsd.org>
@@ -2831,6 +2831,12 @@ mcx_attach(struct device *parent, struct device *self, void *aux)
                goto teardown;
        }
 
+       msix = pci_intr_msix_count(pa->pa_pc, pa->pa_tag);
+       if (msix < 2) {
+               printf(": not enough msi-x vectors\n");
+               goto teardown;
+       }
+
        /*
         * PRM makes no mention of msi interrupts, just legacy and msi-x.
         * mellanox support tells me legacy interrupts are not supported,
@@ -2878,7 +2884,7 @@ mcx_attach(struct device *parent, struct device *self, void *aux)
        printf(", %s, address %s\n", intrstr,
            ether_sprintf(sc->sc_ac.ac_enaddr));
 
-       msix = pci_intr_msix_count(pa->pa_pc, pa->pa_tag);
+       msix--; /* admin ops took one */
        sc->sc_intrmap = intrmap_create(&sc->sc_dev, msix, MCX_MAX_QUEUES,
            INTRMAP_POWEROF2);
        if (sc->sc_intrmap == NULL) {