6.6-stable review patch. If anyone has any objections, please let me know.
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From: Kuen-Han Tsai khtsai@google.com
[ Upstream commit 7bf1158514e410310aec975e630cec99d4e4092f ]
While the userspace program can be notified of gadget state changes, timing issue can lead to missed transitions when reading the state value.
Introduce a trace event for usb_gadget_set_state to reliably track state transitions.
Signed-off-by: Kuen-Han Tsai khtsai@google.com Link: https://lore.kernel.org/r/20250818082722.2952867-1-khtsai@google.com Signed-off-by: Greg Kroah-Hartman gregkh@linuxfoundation.org Stable-dep-of: baeb66fbd420 ("usb: gadget: udc: fix use-after-free in usb_gadget_state_work") Signed-off-by: Sasha Levin sashal@kernel.org Signed-off-by: Greg Kroah-Hartman gregkh@linuxfoundation.org --- drivers/usb/gadget/udc/core.c | 1 + drivers/usb/gadget/udc/trace.h | 5 +++++ 2 files changed, 6 insertions(+)
--- a/drivers/usb/gadget/udc/core.c +++ b/drivers/usb/gadget/udc/core.c @@ -1123,6 +1123,7 @@ void usb_gadget_set_state(struct usb_gad { gadget->state = state; schedule_work(&gadget->work); + trace_usb_gadget_set_state(gadget, 0); } EXPORT_SYMBOL_GPL(usb_gadget_set_state);
--- a/drivers/usb/gadget/udc/trace.h +++ b/drivers/usb/gadget/udc/trace.h @@ -81,6 +81,11 @@ DECLARE_EVENT_CLASS(udc_log_gadget, __entry->ret) );
+DEFINE_EVENT(udc_log_gadget, usb_gadget_set_state, + TP_PROTO(struct usb_gadget *g, int ret), + TP_ARGS(g, ret) +); + DEFINE_EVENT(udc_log_gadget, usb_gadget_frame_number, TP_PROTO(struct usb_gadget *g, int ret), TP_ARGS(g, ret)