[src/trunk]: src/sys/dev/pci wm(4): if_flags and IFNET_LOCK audit

[riastradh <riastradh%NetBSD.org@localhost>]

details:   https://anonhg.NetBSD.org/src/rev/669839504e4b
branches:  trunk
changeset: 368897:669839504e4b
user:      riastradh <riastradh%NetBSD.org@localhost>
date:      Fri Aug 12 10:57:06 2022 +0000

description:
wm(4): if_flags and IFNET_LOCK audit

Don't touch if_flags without IFNET_LOCK:

- If only core lock is held, use sc_if_flags.
- If only txq lock is held, use txq_stopping.
  => Verified all paths guarantee !txq_stopping, so assert.
- Make sure sc_if_flags is updated on stop.
- Make wm_init fail once we enter wm_detach.
- Sprinkle assertions.


Author: Taylor R Campbell <riastradh%NetBSD.org@localhost>

diffstat:

 sys/dev/pci/if_wm.c |  39 ++++++++++++++++++++++++++++-----------
 1 files changed, 28 insertions(+), 11 deletions(-)

diffs (160 lines):

diff -r 4e53a760d8ff -r 669839504e4b sys/dev/pci/if_wm.c
--- a/sys/dev/pci/if_wm.c       Fri Aug 12 10:55:01 2022 +0000
+++ b/sys/dev/pci/if_wm.c       Fri Aug 12 10:57:06 2022 +0000
@@ -1,4 +1,4 @@
-/*     $NetBSD: if_wm.c,v 1.759 2022/08/12 10:55:01 riastradh Exp $    */
+/*     $NetBSD: if_wm.c,v 1.760 2022/08/12 10:57:06 riastradh Exp $    */
 
 /*
  * Copyright (c) 2001, 2002, 2003, 2004 Wasabi Systems, Inc.
@@ -82,7 +82,7 @@
  */
 
 #include <sys/cdefs.h>
-__KERNEL_RCSID(0, "$NetBSD: if_wm.c,v 1.759 2022/08/12 10:55:01 riastradh Exp $");
+__KERNEL_RCSID(0, "$NetBSD: if_wm.c,v 1.760 2022/08/12 10:57:06 riastradh Exp $");
 
 #ifdef _KERNEL_OPT
 #include "opt_net_mpsafe.h"
@@ -705,6 +705,9 @@
 
        struct wm_phyop phy;
        struct wm_nvmop nvm;
+
+       bool sc_dying;
+
 #ifdef WM_DEBUG
        uint32_t sc_debug;
 #endif
@@ -3385,7 +3388,10 @@
                return 0;
 
        /* Stop the interface. Callouts are stopped in it. */
+       IFNET_LOCK(ifp);
+       sc->sc_dying = true;
        wm_stop(ifp, 1);
+       IFNET_UNLOCK(ifp);
 
        pmf_device_deregister(self);
 
@@ -3572,6 +3578,7 @@
 
        if (sc->sc_type >= WM_T_PCH2)
                wm_resume_workarounds_pchlan(sc);
+       IFNET_LOCK(ifp);
        if ((ifp->if_flags & IFF_UP) == 0) {
                /* >= PCH_SPT hardware workaround before reset. */
                if (sc->sc_type >= WM_T_PCH_SPT)
@@ -3590,6 +3597,7 @@
                 * via wm_init().
                 */
        }
+       IFNET_UNLOCK(ifp);
 
        return true;
 }
@@ -4326,6 +4334,7 @@
 
        DPRINTF(sc, WM_DEBUG_INIT, ("%s: %s called\n",
                device_xname(sc->sc_dev), __func__));
+       KASSERT(WM_CORE_LOCKED(sc));
 
        if (sc->sc_type >= WM_T_82544)
                mta_reg = WMREG_CORDOVA_MTA;
@@ -4334,9 +4343,9 @@
 
        sc->sc_rctl &= ~(RCTL_BAM | RCTL_UPE | RCTL_MPE);
 
-       if (ifp->if_flags & IFF_BROADCAST)
+       if (sc->sc_if_flags & IFF_BROADCAST)
                sc->sc_rctl |= RCTL_BAM;
-       if (ifp->if_flags & IFF_PROMISC) {
+       if (sc->sc_if_flags & IFF_PROMISC) {
                sc->sc_rctl |= RCTL_UPE;
                ETHER_LOCK(ec);
                ec->ec_flags |= ETHER_F_ALLMULTI;
@@ -5257,6 +5266,8 @@
        int nexttx;
        uint32_t rctl;
 
+       KASSERT(IFNET_LOCKED(&sc->sc_ethercom.ec_if));
+
        /* First, disable MULR fix in FEXTNVM11 */
        reg = CSR_READ(sc, WMREG_FEXTNVM11);
        reg |= FEXTNVM11_DIS_MULRFIX;
@@ -6482,6 +6493,9 @@
 
        KASSERT(IFNET_LOCKED(ifp));
 
+       if (sc->sc_dying)
+               return ENXIO;
+
        WM_CORE_LOCK(sc);
        ret = wm_init_locked(ifp);
        WM_CORE_UNLOCK(sc);
@@ -7081,6 +7095,7 @@
        struct wm_softc *sc = ifp->if_softc;
 
        ASSERT_SLEEPABLE();
+       KASSERT(IFNET_LOCKED(ifp));
 
        WM_CORE_LOCK(sc);
        wm_stop_locked(ifp, disable ? true : false, true);
@@ -7106,6 +7121,7 @@
 
        DPRINTF(sc, WM_DEBUG_INIT, ("%s: %s called\n",
                device_xname(sc->sc_dev), __func__));
+       KASSERT(IFNET_LOCKED(ifp));
        KASSERT(WM_CORE_LOCKED(sc));
 
        wm_set_stopping_flags(sc);
@@ -7185,6 +7201,7 @@
 
        /* Mark the interface as down and cancel the watchdog timer. */
        ifp->if_flags &= ~IFF_RUNNING;
+       sc->sc_if_flags = ifp->if_flags;
 
        if (disable) {
                for (i = 0; i < sc->sc_nqueues; i++) {
@@ -8384,9 +8401,8 @@
        bool remap = true;
 
        KASSERT(mutex_owned(txq->txq_lock));
-
-       if ((ifp->if_flags & IFF_RUNNING) == 0)
-               return;
+       KASSERT(!txq->txq_stopping);
+
        if ((txq->txq_flags & WM_TXQ_NO_SPACE) != 0)
                return;
 
@@ -9002,9 +9018,8 @@
        bool remap = true;
 
        KASSERT(mutex_owned(txq->txq_lock));
-
-       if ((ifp->if_flags & IFF_RUNNING) == 0)
-               return;
+       KASSERT(!txq->txq_stopping);
+
        if ((txq->txq_flags & WM_TXQ_NO_SPACE) != 0)
                return;
 
@@ -13156,7 +13171,7 @@
                sc->sc_tbi_serdes_ticks = 0;
        }
 
-       if ((sc->sc_ethercom.ec_if.if_flags & IFF_UP) == 0)
+       if ((sc->sc_if_flags & IFF_UP) == 0)
                goto setled;
 
        if ((status & STATUS_LU) == 0) {
@@ -15650,6 +15665,8 @@
 
        DPRINTF(sc, WM_DEBUG_INIT, ("%s: %s called\n",
                device_xname(sc->sc_dev), __func__));
+       KASSERT(IFNET_LOCKED(&sc->sc_ethercom.ec_if));
+
        if (sc->sc_flags & WM_F_HAS_MANAGE) {
                uint32_t manc2h = CSR_READ(sc, WMREG_MANC2H);
                uint32_t manc = CSR_READ(sc, WMREG_MANC);