On Mon, 1 Apr 2024, Feng Chunguo wrote: > Hi Greg KH, > > Sent this path again. > >  the irq should not be turned off here, what happens if some data comes in while this > function is running?  Will it be lost? > --> lost,not receive other irq. > >  When the uart was switching the baud rate from one to other,  this issue can be > reproduced. >> This feels wrong, >> the irq should not be turned off here, what happens if some data comes in while this >> function is running? Will it be lost? thanks, greg k-h Changing rate always risks losing what's currently on wire due to timing related corruption, I don't think there there's a way around that IRQ being enabled or not. -- i.