On Tue, Jan 20, 2015 at 01:08:32PM +0000, Graeme Gregory wrote: [...] > I have tested this series on Juno where it seems to work and also on FVP > model where there are some issues. > > On the FVP when we enter usespace a couple of 32 character strings are > printed then nothing else. 32 Characters is a suspicious number. > > This occurs with both OE based FS from linaro and debian ubstable FS. > > My FVP is version 5602 Can you try this: diff --git a/drivers/tty/serial/amba-pl011.c b/drivers/tty/serial/amba-pl011.c index eb397c7..9ca78db 100644 --- a/drivers/tty/serial/amba-pl011.c +++ b/drivers/tty/serial/amba-pl011.c @@ -1291,6 +1291,7 @@ static void pl011_tx_chars(struct uart_amba_port *uap) writew(uap->port.x_char, uap->port.membase + UART01x_DR); uap->port.icount.tx++; uap->port.x_char = 0; + BUG_ON(uap->tx_avail < 1); uap->tx_avail--; return; } If we can hit that BUG_ON, then it's possible tx_avail is wrapping round here, though I'm not sure if it is likely to occur in practice. I'll have a look for other potential issues... Cheers ---Dave -- To unsubscribe from this list: send the line "unsubscribe linux-serial" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
