On Fri, Jul 13, 2012 at 01:40:48PM -0600, Alex Williamson wrote: > v4: > - KVM_IRQFD_FLAG_LEVEL flag now documented and coded to only be > necessary on assign. > - Lock added to struct _irq_source to maintain the source ID assertion > state to avoid repeat assertions or spurious EOIs. I couldn't figure > out a way to make this work w/o races using atomics and don't see any > way to make use of kvm_irq_line_state. Well not kvm_irq_line_state specifically but what's the problem with looking at irq_state in the correct pic? That is already done atomically. We'll need new APIs for this of course. See specific patch for suggestion. > - GSI support in KVM_EOIFD is dropped since it's not immediately used > and I don't seem to be able to explain why it's useful. It makes it > optional though, which may be a good thing if other archs try to use > this interface. > - eoifd switch to mutex from spinlock (all tested as lockdep safe) > - _irqfd_fdget_lock/_irqfd_put_unlock replaces _irqfd_fdget/_irqfd_put > so we hold the lock for the irqfds ensuring the one we're binding to > doesn't go away while we get a reference to the _irq_source. > - We also pull the GSI off the irqfd rather than specifying it for eoifd. > - eoifd_deactivate renamed to eoifd_destroy to make it blindingly > obvious what it does. Overall looks ok to me. Looks like as written userspace can create any # of eoifds with same irqfd leading to unlimited kernel memory use. See specific patch for suggestion on how to fix. > Patch 3/3 is not for commit and not meant to be ready for commit, it's > just an FYI on what adding back support for a GSI based, non-de-asserting > eoifd will look like. Thanks, > > Alex > > --- > > Alex Williamson (3): > kvm: Add a GSI specification for KVM_EOIFD > kvm: KVM_EOIFD, an eventfd for EOIs > kvm: Extend irqfd to support level interrupts > > > Documentation/virtual/kvm/api.txt | 27 +++ > arch/x86/kvm/x86.c | 3 > include/linux/kvm.h | 24 +++ > include/linux/kvm_host.h | 13 + > virt/kvm/eventfd.c | 349 +++++++++++++++++++++++++++++++++++++ > virt/kvm/kvm_main.c | 11 + > 6 files changed, 423 insertions(+), 4 deletions(-) -- To unsubscribe from this list: send the line "unsubscribe kvm" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
