smp_affinity weirdness in LK 2.6.14

Hello,

I found that I cannot change IRQ affinity in the 2.6.14 kernel. It works however on the 2.6.13.4 and earlier.
2.6.13.4:

# cat /proc/irq/189/smp_affinity
1
# echo 2 > /proc/irq/189/smp_affinity
# cat /proc/irq/189/smp_affinity
2
#

2.6.14:

# cat /proc/irq/189/smp_affinity
1
# echo 2 > /proc/irq/189/smp_affinity
# cat /proc/irq/189/smp_affinity
1
#
/proc/interrupts is also showing that all all IRQs are bound to CPU0. I
must add, that this system is a P4 with HyperThreading support. I've
tried both with CONFIG_IRQBALANCE=y and n but the result is always the
same. With the new kernel I cannot balance the IRQs neither by hand, nor
userspace/kernel tools. Is that normal?

Regards
-Dimitri

This got fixed with 2.6.15-rc4

commit fe655d3a06488c8a188461bca493e9f23fc8c448

Author: Shaohua Li <[email protected]>
Date:   Tue Nov 29 19:34:42 2005 -0800

[PATCH] setting irq affinity is broken in ia32 with MSI enabled

Setting irq affinity stops working when MSI is enabled. With MSI, move_irq is empty, so we can't change irq affinity. It appears a typo in Ashok's original commit for this issue. X86_64 actually is using move_native_irq.

Regards,
-Dimitri Puzin aka Tristan-777