On 1 December 2012 10:29, Janne Karhunen <955...@bugs.launchpad.net> wrote: >> this blocks forever, because the thing that would wake it up is the > signal handler writing to the pipe we're selecting on, but we will never > run the signal handler until select exits > > Duh, makes sense, have to think about this. Thank you for great analysis > :) > > Apparently have to dig into qemu's code to understand this better, but > first thought was that do you think it would be possible to add some > crude hack bit in qemu's signal handler which we could 'almost > atomically' check prior to entering system poll/select/read/whatnot ? > This bit would tell there are user signals queued and handlers should be > executed first.. ?
Nope, it's still not going to be non-racy that way (and it would still be a pretty invasive change so it doesn't really make it easier either I think). -- PMM