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2009-11-01KVM: Fix Xen hvm msr ioctl by adding a flags fieldAvi Kivity
So we can extend it later. Signed-off-by: Avi Kivity <avi@redhat.com>
2009-11-01KVM: add flags to kvm_clock_dataMarcelo Tosatti
Signed-off-by: Marcelo Tosatti <mtosatti@redhat.com>
2009-11-01KVM: allow userspace to adjust kvmclock offsetGlauber Costa
When we migrate a kvm guest that uses pvclock between two hosts, we may suffer a large skew. This is because there can be significant differences between the monotonic clock of the hosts involved. When a new host with a much larger monotonic time starts running the guest, the view of time will be significantly impacted. Situation is much worse when we do the opposite, and migrate to a host with a smaller monotonic clock. This proposed ioctl will allow userspace to inform us what is the monotonic clock value in the source host, so we can keep the time skew short, and more importantly, never goes backwards. Userspace may also need to trigger the current data, since from the first migration onwards, it won't be reflected by a simple call to clock_gettime() anymore. Signed-off-by: Glauber Costa <glommer@redhat.com> Signed-off-by: Marcelo Tosatti <mtosatti@redhat.com>
2009-11-01KVM: Xen PV-on-HVM guest supportEd Swierk
Support for Xen PV-on-HVM guests can be implemented almost entirely in userspace, except for handling one annoying MSR that maps a Xen hypercall blob into guest address space. A generic mechanism to delegate MSR writes to userspace seems overkill and risks encouraging similar MSR abuse in the future. Thus this patch adds special support for the Xen HVM MSR. I implemented a new ioctl, KVM_XEN_HVM_CONFIG, that lets userspace tell KVM which MSR the guest will write to, as well as the starting address and size of the hypercall blobs (one each for 32-bit and 64-bit) that userspace has loaded from files. When the guest writes to the MSR, KVM copies one page of the blob from userspace to the guest. I've tested this patch with a hacked-up version of Gerd's userspace code, booting a number of guests (CentOS 5.3 i386 and x86_64, and FreeBSD 8.0-RC1 amd64) and exercising PV network and block devices. Signed-off-by: Ed Swierk <eswierk@aristanetworks.com> Signed-off-by: Marcelo Tosatti <mtosatti@redhat.com>
2009-09-10KVM: Document KVM_CAP_IRQCHIPAvi Kivity
Signed-off-by: Avi Kivity <avi@redhat.com>
2009-09-10KVM: Document basic APIAvi Kivity
Document the basic API corresponding to the 2.6.22 release. Signed-off-by: Avi Kivity <avi@redhat.com>