| Message ID | 1621644261-1236-1-git-send-email-wcheng@codeaurora.org (mailing list archive) |
|---|---|
| State | Accepted |
| Commit | 6fc1db5e6211e30fbb1cee8d7925d79d4ed2ae14 |
| Headers | show |
| Series | usb: gadget: f_fs: Ensure io_completion_wq is idle during unbind | expand |
diff --git a/drivers/usb/gadget/function/f_fs.c b/drivers/usb/gadget/function/f_fs.c index bf10919..d4844af 100644 --- a/drivers/usb/gadget/function/f_fs.c +++ b/drivers/usb/gadget/function/f_fs.c @@ -3567,6 +3567,9 @@ static void ffs_func_unbind(struct usb_configuration *c, ffs->func = NULL; } + /* Drain any pending AIO completions */ + drain_workqueue(ffs->io_completion_wq); + if (!--opts->refcnt) functionfs_unbind(ffs);
During unbind, ffs_func_eps_disable() will be executed, resulting in completion callbacks for any pending USB requests. When using AIO, irrespective of the completion status, io_data work is queued to io_completion_wq to evaluate and handle the completed requests. Since work runs asynchronously to the unbind() routine, there can be a scenario where the work runs after the USB gadget has been fully removed, resulting in accessing of a resource which has been already freed. (i.e. usb_ep_free_request() accessing the USB ep structure) Explicitly drain the io_completion_wq, instead of relying on the destroy_workqueue() (in ffs_data_put()) to make sure no pending completion work items are running. Signed-off-by: Wesley Cheng <wcheng@codeaurora.org> --- drivers/usb/gadget/function/f_fs.c | 3 +++ 1 file changed, 3 insertions(+)