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Subject: Re: [Qemu-devel] usb-storage assertions
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To: Andrey Korolyov <andrey@xdel.ru>
Cc: Kevin Wolf <kwolf@redhat.com>, hdegoede@redhat.com, "qemu-devel@nongnu.org" <qemu-devel@nongnu.org>

  Hi,

> Probably not enough with driver subsystem to point even at the obvious
> issue in the EHCI driver. I`d start with slowing down an emulated CPU
> 10...100 times via its thread cg, leaving emulator code hanging with
> enough CPU cycles and check if the issue is still here. If roots of
> the crash or endless loop are timing-related, they either would change
> appearance significanly or disappear completely (or vice versa, slow
> an emulator thread). If you don`t have enough time for such blind
> testing, I may check it in a next few days. Since I`ve seen interrupt
> storm complaint on FreeBSD within same conditions, I strongly prefer
> the idea of a race-driven behavior.

Ha!  That nailed it.  /me was looking for a loop in the code, waiting
for the device having finished reset or something like that.  But it
turned out to be a interrupt storm indeed.

cheers,
  Gerd