From 4f2c346e621624315e2a1405e98616a0c5ac146f Mon Sep 17 00:00:00 2001 From: Stuart Hayes Date: Wed, 18 Sep 2024 23:31:43 -0500 Subject: [PATCH] driver core: fix async device shutdown hang Modify device_shutdown() so that supplier devices do not wait for consumer devices to be shut down first when the devlink is sync state only, since the consumer is not dependent on the supplier in this case. Without this change, a circular dependency could hang the system. Fixes: 8064952c6504 ("driver core: shut down devices asynchronously") Signed-off-by: Stuart Hayes Tested-by: Laurence Oberman Tested-by: Nathan Chancellor Link: https://lore.kernel.org/r/20240919043143.1194950-1-stuart.w.hayes@gmail.com Signed-off-by: Greg Kroah-Hartman --- drivers/base/core.c | 10 +++++++++- 1 file changed, 9 insertions(+), 1 deletion(-) diff --git a/drivers/base/core.c b/drivers/base/core.c index b69b82da8837..76513e360496 100644 --- a/drivers/base/core.c +++ b/drivers/base/core.c @@ -4898,8 +4898,16 @@ void device_shutdown(void) idx = device_links_read_lock(); list_for_each_entry_rcu(link, &dev->links.suppliers, c_node, - device_links_read_lock_held()) + device_links_read_lock_held()) { + /* + * sync_state_only suppliers don't need to wait, + * aren't reordered on devices_kset, so making them + * wait could result in a hang + */ + if (device_link_flag_is_sync_state_only(link->flags)) + continue; link->supplier->p->shutdown_after = cookie; + } device_links_read_unlock(idx); put_device(dev); -- 2.50.1