Commit 781e14ea authored Feb 10, 2021 by Mika Westerberg

thunderbolt: Initialize HopID IDAs in tb_switch_alloc()



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: 0b2863ac ("thunderbolt: Add functions for allocating and releasing HopIDs")
Cc: stable@vger.kernel.org
Reported-by: Chiranjeevi Rapolu <chiranjeevi.rapolu@intel.com>
Signed-off-by: Mika Westerberg <mika.westerberg@linux.intel.com>

parent a38fd874

drivers/thunderbolt/switch.c

+8 −10

Original line number	Diff line number	Diff line
		@@ -768,12 +768,6 @@ static int tb_init_port(struct tb_port *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;

		@@ -1842,11 +1836,9 @@ static void tb_switch_release(struct device *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);
		}
		}

		kfree(sw->uuid);
		kfree(sw->device_name);
		@@ -2025,6 +2017,12 @@ struct tb_switch tb_switch_alloc(struct tb tb, struct device *parent,
		/* 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);