| Message ID | 20210421204837.4185-2-m.grzeschik@pengutronix.de |
|---|---|
| State | New |
| Headers | show |
| Series | usb: dwc3: gadget: fix scatter gather support | expand |
Hi, (subject format, please prepend 'usb:') Michael Grzeschik <m.grzeschik@pengutronix.de> writes: > In the dwc3_prepare_trbs_sg routine, when all data from request was > handled pending_sgs should be set to the number of mapped sgs that are ^^ , > not queued up. > > Currently the code will result in pending_sgs == queued_sgs. That > variables value will likely not be zero and break dwc3_prepare_trbs. ^^^^^^^^^ variable's you say it's 'likely'. Got any minimal reproduction method? > This patch fixes the setting of the variable to its intended purpose. > > Signed-off-by: Michael Grzeschik <m.grzeschik@pengutronix.de> please add Fixes tag and Cc stable -- balbi
Michael Grzeschik wrote: > In the dwc3_prepare_trbs_sg routine, when all data from request was > handled pending_sgs should be set to the number of mapped sgs that are > not queued up. > > Currently the code will result in pending_sgs == queued_sgs. That > variables value will likely not be zero and break dwc3_prepare_trbs. > > This patch fixes the setting of the variable to its intended purpose. > > Signed-off-by: Michael Grzeschik <m.grzeschik@pengutronix.de> > --- > drivers/usb/dwc3/gadget.c | 2 +- > 1 file changed, 1 insertion(+), 1 deletion(-) > > diff --git a/drivers/usb/dwc3/gadget.c b/drivers/usb/dwc3/gadget.c > index 6227641f2d318..118b5bcc565d6 100644 > --- a/drivers/usb/dwc3/gadget.c > +++ b/drivers/usb/dwc3/gadget.c > @@ -1242,7 +1242,7 @@ static int dwc3_prepare_trbs_sg(struct dwc3_ep *dep, > * don't include unused SG entries. > */ > if (length == 0) { > - req->num_pending_sgs -= req->request.num_mapped_sgs - req->num_queued_sgs; > + req->num_pending_sgs = req->request.num_mapped_sgs - req->num_queued_sgs; > break; > } > > We update the req->num_pending_sgs every TRB completion interrupt. Doing this will break the current logic. If there's a change to the current logic, it should be part of this patch. Otherwise bisection will fail here. BR, Thinh
diff --git a/drivers/usb/dwc3/gadget.c b/drivers/usb/dwc3/gadget.c index 6227641f2d318..118b5bcc565d6 100644 --- a/drivers/usb/dwc3/gadget.c +++ b/drivers/usb/dwc3/gadget.c @@ -1242,7 +1242,7 @@ static int dwc3_prepare_trbs_sg(struct dwc3_ep *dep, * don't include unused SG entries. */ if (length == 0) { - req->num_pending_sgs -= req->request.num_mapped_sgs - req->num_queued_sgs; + req->num_pending_sgs = req->request.num_mapped_sgs - req->num_queued_sgs; break; }
In the dwc3_prepare_trbs_sg routine, when all data from request was handled pending_sgs should be set to the number of mapped sgs that are not queued up. Currently the code will result in pending_sgs == queued_sgs. That variables value will likely not be zero and break dwc3_prepare_trbs. This patch fixes the setting of the variable to its intended purpose. Signed-off-by: Michael Grzeschik <m.grzeschik@pengutronix.de> --- drivers/usb/dwc3/gadget.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-)