On Fri, 30 May 2014, Huang Rui wrote: > Currently, in usb_sg_wait routine there isn't a timeout on waiting for > completion signal. When using TEST 5 -> 8 at usbtest module to verify > a new device controller with gadget zero, it might be hang on this > phase and this routine waits forever. And it's better to report a > error even though it fails. > > So it should use a test_sg_wait instead of usb_sg_wait to add a > timeout about 10s to export a TIMEOUT error to return in usbtest > driver. > > Reference: http://marc.info/?l=linux-usb&m=140137751813423&w=2 > +/* > + * Some codes are borrowed from usb_sg_wait and sg_clean routines > + */ > +static void test_sg_clean(struct usb_sg_request *io) > +{ > + if (io->urbs) { > + while (io->entries--) > + usb_free_urb(io->urbs[io->entries]); > + kfree(io->urbs); > + io->urbs = NULL; > + } > + io->dev = NULL; > +} > + > +static int test_sg_wait(struct usb_sg_request *io, unsigned long timeout) > +{ > + int i; > + int entries = io->entries; > + long timeleft; ... Ugh, don't make a copy of the existing code. Use the facilities the way they are meant to be used. Like the patch below. Alan Stern Index: usb-3.15/drivers/usb/misc/usbtest.c =================================================================== --- usb-3.15.orig/drivers/usb/misc/usbtest.c +++ usb-3.15/drivers/usb/misc/usbtest.c @@ -7,7 +7,7 @@ #include <linux/moduleparam.h> #include <linux/scatterlist.h> #include <linux/mutex.h> - +#include <linux/timer.h> #include <linux/usb.h> #define SIMPLE_IO_TIMEOUT 10000 /* in milliseconds */ @@ -484,6 +484,13 @@ alloc_sglist(int nents, int max, int var return sg; } +static void sg_timeout(unsigned long _req) +{ + struct usb_sg_request *req = (struct usb_sg_request *) _req; + + usb_sg_cancel(req); +} + static int perform_sglist( struct usbtest_dev *tdev, unsigned iterations, @@ -495,6 +502,9 @@ static int perform_sglist( { struct usb_device *udev = testdev_to_usbdev(tdev); int retval = 0; + struct timer_list sg_timer; + + setup_timer_on_stack(&sg_timer, sg_timeout, (unsigned long) req); while (retval == 0 && iterations-- > 0) { retval = usb_sg_init(req, udev, pipe, @@ -505,7 +515,10 @@ static int perform_sglist( if (retval) break; + mod_timer(&sg_timer, jiffies + + msecs_to_jiffies(SIMPLE_IO_TIMEOUT)); usb_sg_wait(req); + del_timer_sync(&sg_timer); retval = req->status; /* FIXME check resulting data pattern */ -- To unsubscribe from this list: send the line "unsubscribe stable" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html