Hi, On Fri, Mar 04, 2016 at 11:51:19AM +0100, John Ogness wrote: > On 2016-03-04, John Ogness <john.ogness@xxxxxxxxxxxxx> wrote: > > Using v4.5-rc6, I modified musb_h_tx_flush_fifo() to allow infinite > > looping and kept a log of the number of loops that were executed. For > > my test I am regularly seeing 3000-3200 loops (with a max so far of > > 3289). Since there used to be an msleep() in the loop, I never hit the > > warnings before. > > > > With my board, 3200 loops takes about 950us. Perhaps the msleep() > > should be reinserted, but with a retry count of only 3 before aborting > > with the warning. > > Sorry, since musb_h_tx_flush_fifo() can run in interrupt context, > obviously an msleep() cannot be used. It seems increasing the retry > count may be the only option here. Maybe 5000? If the problem with the latest kernel is that only kernel dump happens but usb still works, I'd prefer to not try to fix it by increasing the retries. There are cases in which multiple tx urbs (100+) are queued, increasing the retries could causes minutes of delay in device disconnect. Regards, -Bin. -- To unsubscribe from this list: send the line "unsubscribe linux-usb" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
