From 9344d3fcd3bee7e9ac4ea2acfbf918817678020b Mon Sep 17 00:00:00 2001 From: Stephen Worley Date: Tue, 12 Nov 2019 14:56:56 -0500 Subject: [PATCH] zebra: dplane cancel update thread from correct pthread This code is called from the zebra main pthread during shutdown but the thread event is scheduled via the zebra dplane pthread. Hence, we should be using the `thread_cancel_async()` API to cancel the thread event on a different pthread. This is only ever hit in the rare case that we still have work left to do on the update queue during shutdown. Found via zebra crash: ``` (gdb) bt \#0 __GI_raise (sig=sig@entry=6) at ../sysdeps/unix/sysv/linux/raise.c:50 \#1 0x00007f4e4d3f7535 in __GI_abort () at abort.c:79 \#2 0x00007f4e4d3f740f in __assert_fail_base (fmt=0x7f4e4d559ee0 "%s%s%s:%u: %s%sAssertion `%s' failed.\n%n", assertion=0x7f4e4d9071d0 "master->owner == pthread_self()", file=0x7f4e4d906cf8 "lib/thread.c", line=1185, function=) at assert.c:92 \#3 0x00007f4e4d405102 in __GI___assert_fail (assertion=assertion@entry=0x7f4e4d9071d0 "master->owner == pthread_self()", file=file@entry=0x7f4e4d906cf8 "lib/thread.c", line=line@entry=1185, function=function@entry=0x7f4e4d906b68 <__PRETTY_FUNCTION__.15817> "thread_cancel") at assert.c:101 \#4 0x00007f4e4d8d095a in thread_cancel (thread=0x55b40d01a640) at lib/thread.c:1185 \#5 0x000055b40c291845 in zebra_dplane_shutdown () at zebra/zebra_dplane.c:3274 \#6 0x000055b40c27ee13 in zebra_finalize (dummy=) at zebra/main.c:202 \#7 0x00007f4e4d8d1416 in thread_call (thread=thread@entry=0x7ffcbbc08870) at lib/thread.c:1599 \#8 0x00007f4e4d8a1ef8 in frr_run (master=0x55b40ce35510) at lib/libfrr.c:1024 \#9 0x000055b40c270916 in main (argc=8, argv=0x7ffcbbc08c78) at zebra/main.c:483 (gdb) down \#4 0x00007f4e4d8d095a in thread_cancel (thread=0x55b40d01a640) at lib/thread.c:1185 1185 assert(master->owner == pthread_self()); (gdb) ``` Signed-off-by: Stephen Worley --- zebra/zebra_dplane.c | 4 +++- 1 file changed, 3 insertions(+), 1 deletion(-) diff --git a/zebra/zebra_dplane.c b/zebra/zebra_dplane.c index a88b0a38da81..7f993442a624 100644 --- a/zebra/zebra_dplane.c +++ b/zebra/zebra_dplane.c @@ -3752,7 +3752,9 @@ void zebra_dplane_shutdown(void) zdplane_info.dg_run = false; - THREAD_OFF(zdplane_info.dg_t_update); + if (zdplane_info.dg_t_update) + thread_cancel_async(zdplane_info.dg_t_update->master, + &zdplane_info.dg_t_update, NULL); frr_pthread_stop(zdplane_info.dg_pthread, NULL);