Routers might not have a UID set if the DROM read failed during initialization previously. Normally upon resume the UID is re-read to confirm it's the same device connected. * If the DROM read failed during init but then succeeded during resume it could either be a new device or faulty device * If the DROM read failed during init and also failed during resume it might be a different device plugged in all together. Detect this situation and prevent re-using the same configuration in these cirucmstances. Signed-off-by: Mario Limonciello <mario.limonciello@xxxxxxx> --- v1->v2: * Update commit message drivers/thunderbolt/switch.c | 4 ++++ 1 file changed, 4 insertions(+) diff --git a/drivers/thunderbolt/switch.c b/drivers/thunderbolt/switch.c index b5fb3e76ed09..294518af4ee4 100644 --- a/drivers/thunderbolt/switch.c +++ b/drivers/thunderbolt/switch.c @@ -2980,6 +2980,10 @@ int tb_switch_resume(struct tb_switch *sw) return err; } + /* We don't have any way to confirm this was the same device */ + if (!sw->uid) + return -ENODEV; + if (tb_switch_is_usb4(sw)) err = usb4_switch_read_uid(sw, &uid); else -- 2.34.1