[src/trunk]: src/sys/dev/usb usbnet: Detach interface and mii before waiting ...

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

details:   https://anonhg.NetBSD.org/src/rev/da15a85dbee7
branches:  trunk
changeset: 362499:da15a85dbee7
user:      riastradh <riastradh%NetBSD.org@localhost>
date:      Thu Mar 03 05:48:52 2022 +0000

description:
usbnet: Detach interface and mii before waiting for refcnt to drain.

All outstanding software activity under usbnet's control -- which is
all that participates in the refcnting -- should be quiesced by
stopping and detaching everything.

diffstat:

 sys/dev/usb/usbnet.c |  32 ++++++++++++++++----------------
 1 files changed, 16 insertions(+), 16 deletions(-)

diffs (60 lines):

diff -r e2eed9b9a880 -r da15a85dbee7 sys/dev/usb/usbnet.c
--- a/sys/dev/usb/usbnet.c      Thu Mar 03 05:48:45 2022 +0000
+++ b/sys/dev/usb/usbnet.c      Thu Mar 03 05:48:52 2022 +0000
@@ -1,4 +1,4 @@
-/*     $NetBSD: usbnet.c,v 1.59 2022/03/03 05:48:45 riastradh Exp $    */
+/*     $NetBSD: usbnet.c,v 1.60 2022/03/03 05:48:52 riastradh Exp $    */
 
 /*
  * Copyright (c) 2019 Matthew R. Green
@@ -31,7 +31,7 @@
  */
 
 #include <sys/cdefs.h>
-__KERNEL_RCSID(0, "$NetBSD: usbnet.c,v 1.59 2022/03/03 05:48:45 riastradh Exp $");
+__KERNEL_RCSID(0, "$NetBSD: usbnet.c,v 1.60 2022/03/03 05:48:52 riastradh Exp $");
 
 #include <sys/param.h>
 #include <sys/kernel.h>
@@ -1611,20 +1611,6 @@
        usb_rem_task_wait(un->un_udev, &unp->unp_mcasttask, USB_TASKQ_DRIVER,
            NULL);
 
-       mutex_enter(&unp->unp_core_lock);
-       unp->unp_refcnt--;
-       while (unp->unp_refcnt >= 0) {
-               /* Wait for processes to go away */
-               cv_wait(&unp->unp_detachcv, &unp->unp_core_lock);
-       }
-       mutex_exit(&unp->unp_core_lock);
-
-       usbnet_rx_list_free(un);
-       usbnet_tx_list_free(un);
-
-       callout_destroy(&unp->unp_stat_ch);
-       rnd_detach_source(&unp->unp_rndsrc);
-
        if (mii) {
                mii_detach(mii, MII_PHY_ANY, MII_OFFSET_ANY);
                ifmedia_fini(&mii->mii_media);
@@ -1672,6 +1658,20 @@
        usb_rem_task_wait(un->un_udev, &unp->unp_mcasttask, USB_TASKQ_DRIVER,
            NULL);
 
+       mutex_enter(&unp->unp_core_lock);
+       unp->unp_refcnt--;
+       while (unp->unp_refcnt >= 0) {
+               /* Wait for processes to go away */
+               cv_wait(&unp->unp_detachcv, &unp->unp_core_lock);
+       }
+       mutex_exit(&unp->unp_core_lock);
+
+       usbnet_rx_list_free(un);
+       usbnet_tx_list_free(un);
+
+       callout_destroy(&unp->unp_stat_ch);
+       rnd_detach_source(&unp->unp_rndsrc);
+
        cv_destroy(&unp->unp_detachcv);
        mutex_destroy(&unp->unp_core_lock);
        mutex_destroy(&unp->unp_rxlock);