RE: [BUG][2.6.8.1] serial driver hangs SMP kernel, but not the UP kernel

[Tim_T_Murphy]

> anything i can do to avoid dropping characters without using 
> low_latency, which still hangs SMP kernels?

this patch fixes the problem for me, but its probably an awful hack -- a
brief interrupt storm occurs until tty processes its buffer, but IMHO
that's better than dropping characters.

is there a better alternative?
thanks,
tim

--- 8250-orig.c	2005-01-06 16:25:24.000000000 -0600
+++ 8250.c	2005-01-06 16:27:21.000000000 -0600
@@ -989,8 +989,10 @@
 		if (unlikely(tty->flip.count >= TTY_FLIPBUF_SIZE)) {
 			if(tty->low_latency)
 				tty_flip_buffer_push(tty);
-			/* If this failed then we will throw away the
-			   bytes but must do so to clear interrupts */
+			else
+				break;
+			/* If this failed then we will just leave now 
+			   rather than dropping bytes (interrupts not
cleared) */
 		}
 		ch = serial_inp(up, UART_RX);
 		flag = TTY_NORMAL;
-
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