From: Pat Gefre Date: Thu, 8 Mar 2007 04:41:29 +0000 (-0800) Subject: [PATCH] 2.6 Altix: console fix for CONFIG_DEBUG_SHIRQ usage X-Git-Tag: v2.6.21-rc4~84 X-Git-Url: https://err.no/cgi-bin/gitweb.cgi?a=commitdiff_plain;h=f70c81d4ddb0d300abc252cb594198d3c797a5e1;p=linux-2.6 [PATCH] 2.6 Altix: console fix for CONFIG_DEBUG_SHIRQ usage The sn console driver was snagged by the use of CONFIG_DEBUG_SHIRQ! The request_irq() immediate call to the interrupt handler caused another attempt to lock the port lock - deadlock. This is a patch to fix that. Signed-off-by: Patrick Gefre Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds --- diff --git a/drivers/serial/sn_console.c b/drivers/serial/sn_console.c index 253ceb895c..a27e9e92cb 100644 --- a/drivers/serial/sn_console.c +++ b/drivers/serial/sn_console.c @@ -635,25 +635,6 @@ static irqreturn_t sn_sal_interrupt(int irq, void *dev_id) return IRQ_HANDLED; } -/** - * sn_sal_connect_interrupt - Request interrupt, handled by sn_sal_interrupt - * @port: Our sn_cons_port (which contains the uart port) - * - * returns the console irq if interrupt is successfully registered, else 0 - * - */ -static int sn_sal_connect_interrupt(struct sn_cons_port *port) -{ - if (request_irq(SGI_UART_VECTOR, sn_sal_interrupt, - IRQF_DISABLED | IRQF_SHARED, - "SAL console driver", port) >= 0) { - return SGI_UART_VECTOR; - } - - printk(KERN_INFO "sn_console: console proceeding in polled mode\n"); - return 0; -} - /** * sn_sal_timer_poll - this function handles polled console mode * @data: A pointer to our sn_cons_port (which contains the uart port) @@ -746,30 +727,31 @@ static void __init sn_sal_switch_to_asynch(struct sn_cons_port *port) * mode. We were previously in asynch/polling mode (using init_timer). * * We attempt to switch to interrupt mode here by calling - * sn_sal_connect_interrupt. If that works out, we enable receive interrupts. + * request_irq. If that works out, we enable receive interrupts. */ static void __init sn_sal_switch_to_interrupts(struct sn_cons_port *port) { - int irq; unsigned long flags; - if (!port) - return; - - DPRINTF("sn_console: switching to interrupt driven console\n"); - - spin_lock_irqsave(&port->sc_port.lock, flags); + if (port) { + DPRINTF("sn_console: switching to interrupt driven console\n"); - irq = sn_sal_connect_interrupt(port); + if (request_irq(SGI_UART_VECTOR, sn_sal_interrupt, + IRQF_DISABLED | IRQF_SHARED, + "SAL console driver", port) >= 0) { + spin_lock_irqsave(&port->sc_port.lock, flags); + port->sc_port.irq = SGI_UART_VECTOR; + port->sc_ops = &intr_ops; - if (irq) { - port->sc_port.irq = irq; - port->sc_ops = &intr_ops; - - /* turn on receive interrupts */ - ia64_sn_console_intr_enable(SAL_CONSOLE_INTR_RECV); + /* turn on receive interrupts */ + ia64_sn_console_intr_enable(SAL_CONSOLE_INTR_RECV); + spin_unlock_irqrestore(&port->sc_port.lock, flags); + } + else { + printk(KERN_INFO + "sn_console: console proceeding in polled mode\n"); + } } - spin_unlock_irqrestore(&port->sc_port.lock, flags); } /*