pppx_if containing tree and per pppx_dev list are protected by rwlock so
these splx(9) related dances and commentaries are not actual.
Also pxd_svcq protected by NET_LOCK().
Index: sys/net/if_pppx.c
===================================================================
RCS file: /cvs/src/sys/net/if_pppx.c,v
retrieving revision 1.81
diff -u -p -r1.81 if_pppx.c
--- sys/net/if_pppx.c 7 Apr 2020 07:11:22 -0000 1.81
+++ sys/net/if_pppx.c 7 Apr 2020 09:06:35 -0000
@@ -126,7 +126,7 @@ struct pppx_dev {
struct selinfo pxd_wsel;
struct mutex pxd_wsel_mtx;
- /* queue of packets for userland to service - protected by splnet */
+ /* queue of packets for userland to service - protected by NET_LOCK() */
struct mbuf_queue pxd_svcq;
int pxd_waiting;
LIST_HEAD(,pppx_if) pxd_pxis;
@@ -622,7 +622,6 @@ pppx_if_next_unit(void)
rw_assert_wrlock(&pppx_ifs_lk);
- /* this is safe without splnet since we're not modifying it */
do {
int found = 0;
RBT_FOREACH(pxi, pppx_ifs, &pppx_ifs) {
@@ -842,7 +841,6 @@ pppx_add_session(struct pppx_dev *pxd, s
pxi->pxi_key.pxik_protocol = req->pr_protocol;
pxi->pxi_dev = pxd;
- /* this is safe without splnet since we're not modifying it */
if (RBT_FIND(pppx_ifs, &pppx_ifs, pxi) != NULL) {
pool_put(pppx_if_pl, pxi);
error = EADDRINUSE;
@@ -850,8 +848,7 @@ pppx_add_session(struct pppx_dev *pxd, s
goto out;
}
- if (RBT_INSERT(pppx_ifs, &pppx_ifs, pxi) != NULL)
- panic("%s: pppx_ifs modified while lock was held", __func__);
+ RBT_INSERT(pppx_ifs, &pppx_ifs, pxi);
LIST_INSERT_HEAD(&pxd->pxd_pxis, pxi, pxi_list);
rw_exit_write(&pppx_ifs_lk);
@@ -1039,8 +1036,7 @@ pppx_if_destroy(struct pppx_dev *pxd, st
NET_LOCK();
rw_enter_write(&pppx_ifs_lk);
- if (RBT_REMOVE(pppx_ifs, &pppx_ifs, pxi) == NULL)
- panic("%s: pppx_ifs modified while lock was held", __func__);
+ RBT_REMOVE(pppx_ifs, &pppx_ifs, pxi);
LIST_REMOVE(pxi, pxi_list);
rw_exit_write(&pppx_ifs_lk);
