Hi all, How is this going? http://www.archivum.info/[EMAIL PROTECTED]/2008-02/msg00169.html
I use serial as guest's default stdio on powerpc platform. When displaying a number of characters, e.g. cat a big ascii file, the serial always hangs as it encounters overwhelming interrupts, and then complains "serial8250: too much work for irq 42". The problem is that: serial in qemu generate an interrupt on every output character, while Linux driver reads serial data in a loop but gives up after a fixed number (256) of iterations. So if serial output more than 256 characters in a short time, the serial die. I had to use the patch below to get it worked around. So what is the best way to solve it? --- diff --git a/drivers/serial/8250.c b/drivers/serial/8250.c index be95e55..af3e569 100644 --- a/drivers/serial/8250.c +++ b/drivers/serial/8250.c @@ -70,7 +70,7 @@ static unsigned int nr_uarts = CONFIG_SERIAL_8250_RUNTIME_UARTS; #define DEBUG_INTR(fmt...) do { } while (0) #endif -#define PASS_LIMIT 256 +#define PASS_LIMIT 65536 /* * We default to IRQ0 for the "no irq" hack. Some