On Tuesday 05 February 2008 15:07:27 H. Peter Anvin wrote: > Rob Landley wrote: > > When running a 2.6.24 kernel built for x86-64 under qemu via serial > > console, doing CPU-intensive things that also produce a lot of output > > (such as compiling software) tends to produce the error message in the > > title. > > > > Anybody have a clue why? It doesn't seem to cause an actual problem, but > > it's kind of annoying. > > > > (If it's a qemu issue, I can go bother them. It's possible that qemu > > isn't delivering interrupts as often as it expects, since that's limited > > by the granularity of the host timer; I know the clock in qemu can run a > > bit slow because it only gets clock interrupts when the host system isn't > > too busy to schedule the emulator. But this doesn't usually cause a > > problem. I _think_ the message is just a "this should never happen" type > > warning, which is happening to me. But I break stuff. :) > > This is because Qemu spews data to the serial port without any rate > limiting; this causes the in-kernel serial port driver to think the port > is stuck. The serial port emulation needs to make it possible to drain > the virtual FIFO every now and then, as opposed to filling it again > immediately. > > -hpa
Thanks. cc'd the right list on this one. :) Rob -- "One of my most productive days was throwing away 1000 lines of code." - Ken Thompson.
