Re: [PATCH] ata: Don't use NO_IRQ in pata_of_platform driver

Geert Uytterhoeven
2011-12-06T11:00:17Z

On Tue, Dec 6, 2011 at 11:46, Russell King - ARM Linux
<linux@arm.linux.org.uk> wrote:
> But.. let's make one thing clear: Alan Cox and Linus have been going on
> about how IRQ0 should not be used.  Let's be crystal clear: even x86
> uses IRQ0.  It happens to be the PIC timer, and that gets claimed early
> on during the x86 boot.  So please don't tell me that x86 avoids IRQ0.
> It doesn't.  It just happens that x86 never shows IRQ0 to anything but
> the i8253 PIC driver.

It's shown in /proc/interrupts due to a "bug" in show_interrupts().
The (gmail damaged) patch below fixes this bug.

>From 46f51a2d42548358868a34df00c2a4e47bbdf691 Mon Sep 17 00:00:00 2001
From: Geert Uytterhoeven <Geert.Uytterhoeven@eu.sony.com>
Date: Tue, 6 Dec 2011 11:55:05 +0100
Subject: [PATCH] /proc/interrupts: irq zero is invalid

As zero is an invalid irq number, show_interrupts() should not try to
print it. Just return after printing the header for i == 0.

Signed-off-by: Geert Uytterhoeven <geert@linux-m68k.org>
---
kernel/irq/proc.c | 1 +
1 files changed, 1 insertions(+), 0 deletions(-)

diff --git a/kernel/irq/proc.c b/kernel/irq/proc.c
index 4bd4faa..5b8bbf0 100644
--- a/kernel/irq/proc.c
+++ b/kernel/irq/proc.c
@@ -439,6 +439,7 @@ int show_interrupts(struct seq_file *p, void *v)
for_each_online_cpu(j)
seq_printf(p, "CPU%-8d", j);
seq_putc(p, '\n');
+ return 0;
}

desc = irq_to_desc(i);
--
1.7.0.4

Gr{oetje,eeting}s,

Geert

--
Geert Uytterhoeven -- There's lots of Linux beyond ia32 -- geert@linux-m68k.org

In personal conversations with technical people, I call myself a hacker. But
when I'm talking to journalists I just say "programmer" or something like that.
-- Linus Torvalds