> This patch is needed as is. One real risk this is protecting > against is the call of cpu_interrupt(cpu_foo) when the calling > thread is not cpu_foo's thread--this write to interrupt_request > might race with other writes, e.g. another call to cpu_interrupt > from another thread, or the clearing of interrupt_request by > cpu_foo.
But it should be protected by the iothread lock. That requires a lot of auditing. :( I prefer to go with patch 23 first and then optimize things on top (not that I don't like the optimization, since it also affects KVM!). :) Paolo > Patch 23 fixes another issue--bootup hangs without it. The amount > of code wrapped by the iothread lock can be reduced, though. > Will fix.
