On Tue, 2006-12-12 at 14:18 +0100, Johannes Berg wrote:

quoted

?? Context for downing cpu should better be well-defined. Just do this
in cpu_die if it is really required.

It is actually required but I'm not exactly sure why. When I don't do
this, I end up with preempt_count() 0x100000 (IIRC, notes not here at

                                      ^^^^^^^^ typo, should be 0x10000

the moment).

I think this is because the suspend code has interrupts disabled already
when downing the CPUs.

Also, the /sys/devices/system/cpu/cpuN/online thing doesn't disable
interrupts before downing the CPU thus that works without this.

johannes