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