diff options
| author | cinap_lenrek <cinap_lenrek@felloff.net> | 2022-02-16 22:31:31 +0000 |
|---|---|---|
| committer | cinap_lenrek <cinap_lenrek@felloff.net> | 2022-02-16 22:31:31 +0000 |
| commit | 7289f371a0b113c12add274c4d4aa84d0c147dee (patch) | |
| tree | caaadea3c6dff299367b9079558141efc2f1ea65 /sys/src/9/ip/loopbackmedium.c | |
| parent | 755880b19f365c3f98eac5c7de1d8b25f773ace3 (diff) | |
devip: dont hold ifc wlock during medium bind/unbind
Wlock()'ing the ifc causes a deadlock with Medium
bind/unbind as the routine can walk /net, while
ndb/dns or ndb/cs are currently blocked enumerating
/net/ipifc/*.
The fix is to have a fake medium, called "unbound",
that is set temporarily during the call of Medium
bind and unbind.
That way, the interface rwlock can be released while
bind/unbind is in progress.
The ipifcunbind() routine will refuse to unbind a
ifc that is currently assigned to the "unbound"
medium, preventing any accidents.
Diffstat (limited to 'sys/src/9/ip/loopbackmedium.c')
| -rw-r--r-- | sys/src/9/ip/loopbackmedium.c | 6 |
1 files changed, 0 insertions, 6 deletions
diff --git a/sys/src/9/ip/loopbackmedium.c b/sys/src/9/ip/loopbackmedium.c index 036de1137..f1755152b 100644 --- a/sys/src/9/ip/loopbackmedium.c +++ b/sys/src/9/ip/loopbackmedium.c @@ -44,26 +44,20 @@ loopbackunbind(Ipifc *ifc) while(waserror()) ; - /* wat for reader to start */ while(lb->readp == (void*)-1) tsleep(&up->sleep, return0, 0, 300); if(lb->readp != nil) postnote(lb->readp, 1, "unbind", 0); - poperror(); - wunlock(ifc); while(waserror()) ; - /* wait for reader to die */ while(lb->readp != nil) tsleep(&up->sleep, return0, 0, 300); - poperror(); - wlock(ifc); /* clean up */ qfree(lb->q); |