[PATCH 5.10 123/157] thunderbolt: Initialize HopID IDAs in tb_switch_alloc()

From: Greg Kroah-Hartman
Date: Mon Mar 22 2021 - 08:51:17 EST


From: Mika Westerberg <mika.westerberg@xxxxxxxxxxxxxxx>

commit 781e14eaa7d168dc07d2a2eea5c55831a5bb46f3 upstream.

If there is a failure before the tb_switch_add() is called the switch
object is released by tb_switch_release() but at that point HopID IDAs
have not yet been initialized. So we see splat like this:

BUG: spinlock bad magic on CPU#2, kworker/u8:5/115
...
Workqueue: thunderbolt0 tb_handle_hotplug
Call Trace:
dump_stack+0x97/0xdc
? spin_bug+0x9a/0xa7
do_raw_spin_lock+0x68/0x98
_raw_spin_lock_irqsave+0x3f/0x5d
ida_destroy+0x4f/0x127
tb_switch_release+0x6d/0xfd
device_release+0x2c/0x7d
kobject_put+0x9b/0xbc
tb_handle_hotplug+0x278/0x452
process_one_work+0x1db/0x396
worker_thread+0x216/0x375
kthread+0x14d/0x155
? pr_cont_work+0x58/0x58
? kthread_blkcg+0x2e/0x2e
ret_from_fork+0x1f/0x40

Fix this by always initializing HopID IDAs in tb_switch_alloc().

Fixes: 0b2863ac3cfd ("thunderbolt: Add functions for allocating and releasing HopIDs")
Cc: stable@xxxxxxxxxxxxxxx
Reported-by: Chiranjeevi Rapolu <chiranjeevi.rapolu@xxxxxxxxx>
Signed-off-by: Mika Westerberg <mika.westerberg@xxxxxxxxxxxxxxx>
Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>
---
drivers/thunderbolt/switch.c | 18 ++++++++----------
1 file changed, 8 insertions(+), 10 deletions(-)

--- a/drivers/thunderbolt/switch.c
+++ b/drivers/thunderbolt/switch.c
@@ -761,12 +761,6 @@ static int tb_init_port(struct tb_port *

tb_dump_port(port->sw->tb, &port->config);

- /* Control port does not need HopID allocation */
- if (port->port) {
- ida_init(&port->in_hopids);
- ida_init(&port->out_hopids);
- }
-
INIT_LIST_HEAD(&port->list);
return 0;

@@ -1764,10 +1758,8 @@ static void tb_switch_release(struct dev
dma_port_free(sw->dma_port);

tb_switch_for_each_port(sw, port) {
- if (!port->disabled) {
- ida_destroy(&port->in_hopids);
- ida_destroy(&port->out_hopids);
- }
+ ida_destroy(&port->in_hopids);
+ ida_destroy(&port->out_hopids);
}

kfree(sw->uuid);
@@ -1947,6 +1939,12 @@ struct tb_switch *tb_switch_alloc(struct
/* minimum setup for tb_find_cap and tb_drom_read to work */
sw->ports[i].sw = sw;
sw->ports[i].port = i;
+
+ /* Control port does not need HopID allocation */
+ if (i) {
+ ida_init(&sw->ports[i].in_hopids);
+ ida_init(&sw->ports[i].out_hopids);
+ }
}

ret = tb_switch_find_vse_cap(sw, TB_VSE_CAP_PLUG_EVENTS);