Big problems in acpi/event.c (needs seq_printf?)

[Pavel Machek]

Hi!

acpi/event.c needs some heavy facelifting.

This one is needed so that return value (ERESTARTSYS) is propagated
from bus_receive_event(). If this is not done, suspend/resume causes
cat /proc/acpi/event to fail with -EIO. Please apply.

However, there are more problems with event.c:

* it uses spinlock_irq to protect event_is_open(). That's huge
overkill, atomic_t should be enough here, and it is never accessed
from interrupt anyway.

* its racy w.r.t. concurent readers (and yes, you *can* have concurent
readers, think threads). acpi_system_read_event() uses static
variables, without any locking. Probably seq_printf() converstion is
needed.
								Pavel

--- clean/drivers/acpi/event.c	2003-02-15 18:51:16.000000000 +0100
+++ linux/drivers/acpi/event.c	2004-04-19 18:43:58.000000000 +0200
@@ -63,9 +58,8 @@
 			return_VALUE(-EAGAIN);
 
 		result = acpi_bus_receive_event(&event);
-		if (result) {
-			return_VALUE(-EIO);
-		}
+		if (result)
+			return_VALUE(result);
 
 		chars_remaining = sprintf(str, "%s %s %08x %08x\n", 
 			event.device_class?event.device_class:"<unknown>",

-- 
When do you have a heart between your knees?
[Johanka's followup: and *two* hearts?]
-
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at  http://vger.kernel.org/majordomo-info.html
Please read the FAQ at  http://www.tux.org/lkml/