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There was an issue when you did the following: - setup and bind an hid gadget - open /dev/hidg0 - use the resulting fd in EPOLL_CTL_ADD - unbind the UDC - bind the UDC - use the fd in EPOLL_CTL_DEL When CONFIG_DEBUG_LIST was enabled, a list_del corruption was reported within remove_wait_queue (via ep_remove_wait_queue). After some debugging I found out that the queues, which f_hid registers via poll_wait were the problem. These were initialized using init_waitqueue_head inside hidg_bind. So effectively, the bind function re-initialized the queues while there were still items in them. The solution is to move the initialization from hidg_bind to hidg_alloc to extend their lifetimes to the lifetime of the function instance. Additionally, I found many other possibly problematic init calls in the bind function, which I moved as well. Signed-off-by: Michael Zimmermann <sigmaepsilon92@gmail.com> Cc: stable <stable@kernel.org> Link: https://patch.msgid.link/20260331184844.2388761-1-sigmaepsilon92@gmail.com Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>