Messages in this thread | | | Date | Wed, 14 Mar 2007 17:15:30 -0700 (PDT) | From | Linus Torvalds <> | Subject | Re: [patch 13/13] signalfd/timerfd/asyncfd v5 - KAIO asyncfd support (example/maybe-broken) ... |
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On Wed, 14 Mar 2007, Davide Libenzi wrote: > > > > That won't work. aio_complete() is supposed to be irq safe. > > Can you point me to a kernel path that ends up calling aio_complete() in a > do-not-sleep mode?
All of them.
It's called from dio_bio_end_aio(), which is the bi_end_io function for an AIO action. Which in turn is called at IO completion time.
Which is basically _always_ interrupt context.
So you cannot sleep. It's not about holding spinlocks (which it might well do as well). It's about a much more fundamental issue: you can only sleep in process context, not from interrupts.
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