usb: dwc3: gadget: Fix dwc3_calc_trbs_left()
commit 51f1954a upstream. We can't depend on the TRB's HWO bit to determine if the TRB ring is "full". A TRB is only available when the driver had processed it, not when the controller consumed and relinquished the TRB's ownership to the driver. Otherwise, the driver may overwrite unprocessed TRBs. This can happen when many transfer events accumulate and the system is slow to process them and/or when there are too many small requests. If a request is in the started_list, that means there is one or more unprocessed TRBs remained. Check this instead of the TRB's HWO bit whether the TRB ring is full. Fixes: c4233573 ("usb: dwc3: gadget: prepare TRBs on update transfers too") Cc: <stable@vger.kernel.org> Acked-by:Felipe Balbi <balbi@kernel.org> Signed-off-by:
Thinh Nguyen <Thinh.Nguyen@synopsys.com> Link: https://lore.kernel.org/r/e91e975affb0d0d02770686afc3a5b9eb84409f6.1629335416.git.Thinh.Nguyen@synopsys.com Signed-off-by:
Greg Kroah-Hartman <gregkh@linuxfoundation.org>
parent
af130541
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