[SERIAL]: Fix console write locking in sparc drivers.
Mirror the logic in 8250 for proper console write locking
when SYSRQ is triggered or an OOPS is in progress.
Signed-off-by: David S. Miller <davem@davemloft.net>
diff --git a/drivers/serial/sunhv.c b/drivers/serial/sunhv.c
index 96557e6..17bcca5 100644
--- a/drivers/serial/sunhv.c
+++ b/drivers/serial/sunhv.c
@@ -440,8 +440,16 @@
{
struct uart_port *port = sunhv_port;
unsigned long flags;
+ int locked = 1;
- spin_lock_irqsave(&port->lock, flags);
+ local_irq_save(flags);
+ if (port->sysrq) {
+ locked = 0;
+ } else if (oops_in_progress) {
+ locked = spin_trylock(&port->lock);
+ } else
+ spin_lock(&port->lock);
+
while (n > 0) {
unsigned long ra = __pa(con_write_page);
unsigned long page_bytes;
@@ -469,7 +477,10 @@
ra += written;
}
}
- spin_unlock_irqrestore(&port->lock, flags);
+
+ if (locked)
+ spin_unlock(&port->lock);
+ local_irq_restore(flags);
}
static inline void sunhv_console_putchar(struct uart_port *port, char c)
@@ -488,7 +499,15 @@
{
struct uart_port *port = sunhv_port;
unsigned long flags;
- int i;
+ int i, locked = 1;
+
+ local_irq_save(flags);
+ if (port->sysrq) {
+ locked = 0;
+ } else if (oops_in_progress) {
+ locked = spin_trylock(&port->lock);
+ } else
+ spin_lock(&port->lock);
spin_lock_irqsave(&port->lock, flags);
for (i = 0; i < n; i++) {
@@ -496,7 +515,10 @@
sunhv_console_putchar(port, '\r');
sunhv_console_putchar(port, *s++);
}
- spin_unlock_irqrestore(&port->lock, flags);
+
+ if (locked)
+ spin_unlock(&port->lock);
+ local_irq_restore(flags);
}
static struct console sunhv_console = {