Re: [KVM PATCH v8 3/3] KVM: add iosignalfd support

From: Avi Kivity
Date: Tue Jun 23 2009 - 05:57:19 EST

On 06/23/2009 11:56 AM, Michael S. Tsirkin wrote:
On Thu, Jun 18, 2009 at 08:30:46PM -0400, Gregory Haskins wrote:
+static int
+iosignalfd_group_in_range(struct kvm_io_device *this, gpa_t addr, int len,
+ int is_write)
+ struct _iosignalfd_group *p = to_group(this);
+ return ((addr>= p->addr&& (addr< p->addr + p->length)));

I think I see a problem here. For virtio, we do not necessarily want all
virtqueues for a device to live in kernel: there might be control
virtqueues that we want to leave in userspace. Since this claims all
writes to a specific address, the signal never makes it to userspace.

Userspace could create an eventfd for this control queue and wait for it to fire.

error compiling committee.c: too many arguments to function

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