2007-12-08 01:48:17

by Kevin Hilman

[permalink] [raw]
Subject: [PATCH/RFC -rt] local_bh_enable() is safe for irqs_disabled()

In local_bh_enable() there is a WARN_ON(irqs_disabled()), but looking
at the rest of the code, it seems it expects to be used with
interrupts off, so is this warning really necessary?

I hit this warning in the ads7846 touchscreen driver timer function
where enable_irq() may be called with interrupts disabled. Since
enable_irq now calls local_bh_disable/enable for IRQ resend, this
warning is triggered.

Patch against 2.6.23.9-rt12

Signed-off-by: Kevin Hilman <[email protected]>

diff --git a/kernel/softirq.c b/kernel/softirq.c
index 4c19017..68149ae 100644
--- a/kernel/softirq.c
+++ b/kernel/softirq.c
@@ -207,7 +207,6 @@ void local_bh_enable(void)

WARN_ON_ONCE(in_irq());
#endif
- WARN_ON_ONCE(irqs_disabled());

#ifdef CONFIG_TRACE_IRQFLAGS
local_irq_save(flags);