block/qed: add missing graph rdlock in qed_need_check_timer_entry

This function is called in two different places:
- timer callback, which does not take the graph rdlock.
- bdrv_qed_drain_begin(), which is .bdrv_drain_begin()
  callback documented as function that does not take the lock.

Since it calls recursive functions that traverse the
graph, we need to protect them with the graph rdlock.

Signed-off-by: Emanuele Giuseppe Esposito <eesposit@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
Message-Id: <20230203152202.49054-7-kwolf@redhat.com>
Reviewed-by: Emanuele Giuseppe Esposito <eesposit@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
This commit is contained in:
Emanuele Giuseppe Esposito 2023-02-03 16:21:45 +01:00 committed by Kevin Wolf
parent 26c518ab1e
commit c16b8bd4e5

View File

@ -282,11 +282,12 @@ static void coroutine_fn qed_unplug_allocating_write_reqs(BDRVQEDState *s)
qemu_co_mutex_unlock(&s->table_lock);
}
static void coroutine_fn qed_need_check_timer(BDRVQEDState *s)
static void coroutine_fn GRAPH_RDLOCK qed_need_check_timer(BDRVQEDState *s)
{
int ret;
trace_qed_need_check_timer_cb(s);
assert_bdrv_graph_readable();
if (!qed_plug_allocating_write_reqs(s)) {
return;
@ -312,6 +313,7 @@ static void coroutine_fn qed_need_check_timer(BDRVQEDState *s)
static void coroutine_fn qed_need_check_timer_entry(void *opaque)
{
BDRVQEDState *s = opaque;
GRAPH_RDLOCK_GUARD();
qed_need_check_timer(opaque);
bdrv_dec_in_flight(s->bs);