kernel.git/Documentation/virtual/kvm/api.txt, branch linux-4.0.y

Merge tag 'kvm-s390-next-20150122' of git://git.kernel.org/pub/scm/linux/kernel/git/kvms390/linux into kvm-next

2015-01-23T13:33:36Z

KVM: s390: fixes and features for kvm/next (3.20) 1. Generic - sparse warning (make function static) - optimize locking - bugfixes for interrupt injection - fix MVPG addressing modes 2. hrtimer/wakeup fun A recent change can cause KVM hangs if adjtime is used in the host. The hrtimer might wake up too early or too late. Too early is fatal as vcpu_block will see that the wakeup condition is not met and sleep again. This CPU might never wake up again. This series addresses this problem. adjclock slowing down the host clock will result in too late wakeups. This will require more work. In addition to that we also change the hrtimer from REALTIME to MONOTONIC to avoid similar problems with timedatectl set-time. 3. sigp rework We will move all "slow" sigps to QEMU (protected with a capability that can be enabled) to avoid several races between concurrent SIGP orders. 4. Optimize the shadow page table Provide an interface to announce the maximum guest size. The kernel will use that to make the pagetable 2,3,4 (or theoretically) 5 levels. 5. Provide an interface to set the guest TOD We now use two vm attributes instead of two oneregs, as oneregs are vcpu ioctl and we don't want to call them from other threads. 6. Protected key functions The real HMC allows to enable/disable protected key CPACF functions. Lets provide an implementation + an interface for QEMU to activate this the protected key instructions.

KVM: s390: forward most SIGP orders to user space

2015-01-23T12:25:37Z

Most SIGP orders are handled partially in kernel and partially in user space. In order to: - Get a correct SIGP SET PREFIX handler that informs user space - Avoid race conditions between concurrently executed SIGP orders - Serialize SIGP orders per VCPU We need to handle all "slow" SIGP orders in user space. The remaining ones to be handled completely in kernel are: - SENSE - SENSE RUNNING - EXTERNAL CALL - EMERGENCY SIGNAL - CONDITIONAL EMERGENCY SIGNAL According to the PoP, they have to be fast. They can be executed without conflicting to the actions of other pending/concurrently executing orders (e.g. STOP vs. START). This patch introduces a new capability that will - when enabled - forward all but the mentioned SIGP orders to user space. The instruction counters in the kernel are still updated. Reviewed-by: Cornelia Huck Signed-off-by: David Hildenbrand Signed-off-by: Christian Borntraeger

KVM: s390: new parameter for SIGP STOP irqs

2015-01-23T12:25:33Z

In order to get rid of the action_flags and to properly migrate pending SIGP STOP irqs triggered e.g. by SIGP STOP AND STORE STATUS, we need to remember whether to store the status when stopping. For this reason, a new parameter (flags) for the SIGP STOP irq is introduced. These flags further define details of the requested STOP and can be easily migrated. Reviewed-by: Thomas Huth Acked-by: Cornelia Huck Signed-off-by: David Hildenbrand Signed-off-by: Christian Borntraeger

arm/arm64: KVM: allow userland to request a virtual GICv3

2015-01-20T17:25:33Z

With all of the GICv3 code in place now we allow userland to ask the kernel for using a virtual GICv3 in the guest. Also we provide the necessary support for guests setting the memory addresses for the virtual distributor and redistributors. This requires some userland code to make use of that feature and explicitly ask for a virtual GICv3. Document that KVM_CREATE_IRQCHIP only works for GICv2, but is considered legacy and using KVM_CREATE_DEVICE is preferred. Signed-off-by: Andre Przywara Signed-off-by: Christoffer Dall

Merge tag 'kvm-arm-for-3.19-take2' of git://git.kernel.org/pub/scm/linux/kernel/git/kvmarm/kvmarm into HEAD

2014-12-15T12:06:40Z

Second round of changes for KVM for arm/arm64 for v3.19; fixes reboot problems, clarifies VCPU init, and fixes a regression concerning the VGIC init flow. Conflicts: arch/ia64/kvm/kvm-ia64.c [deleted in HEAD and modified in kvmarm]

arm/arm64: KVM: Turn off vcpus on PSCI shutdown/reboot

2014-12-13T13:15:27Z

When a vcpu calls SYSTEM_OFF or SYSTEM_RESET with PSCI v0.2, the vcpus should really be turned off for the VM adhering to the suggestions in the PSCI spec, and it's the sane thing to do. Also, clarify the behavior and expectations for exits to user space with the KVM_EXIT_SYSTEM_EVENT case. Acked-by: Marc Zyngier Signed-off-by: Christoffer Dall

arm/arm64: KVM: Clarify KVM_ARM_VCPU_INIT ABI

2014-12-13T13:15:26Z

It is not clear that this ioctl can be called multiple times for a given vcpu. Userspace already does this, so clarify the ABI. Also specify that userspace is expected to always make secondary and subsequent calls to the ioctl with the same parameters for the VCPU as the initial call (which userspace also already does). Add code to check that userspace doesn't violate that ABI in the future, and move the kvm_vcpu_set_target() function which is currently duplicated between the 32-bit and 64-bit versions in guest.c to a common static function in arm.c, shared between both architectures. Acked-by: Marc Zyngier Signed-off-by: Christoffer Dall

arm/arm64: KVM: Correct KVM_ARM_VCPU_INIT power off option

2014-12-13T13:15:25Z

The implementation of KVM_ARM_VCPU_INIT is currently not doing what userspace expects, namely making sure that a vcpu which may have been turned off using PSCI is returned to its initial state, which would be powered on if userspace does not set the KVM_ARM_VCPU_POWER_OFF flag. Implement the expected functionality and clarify the ABI. Acked-by: Marc Zyngier Signed-off-by: Christoffer Dall

kvm: Documentation: remove ia64

2014-11-20T10:08:55Z

kvm/ia64 is gone, clean up Documentation too. Signed-off-by: Paolo Bonzini

kvm: drop unsupported capabilities, fix documentation

2014-11-03T11:07:29Z

No kernel ever reported KVM_CAP_DEVICE_MSIX, KVM_CAP_DEVICE_MSI, KVM_CAP_DEVICE_ASSIGNMENT, KVM_CAP_DEVICE_DEASSIGNMENT. This makes the documentation wrong, and no application ever written to use these capabilities has a chance to work correctly. The only way to detect support is to try, and test errno for ENOTTY. That's unfortunate, but we can't fix the past. Document the actual semantics, and drop the definitions from the exported header to make it easier for application developers to note and fix the bug. Signed-off-by: Michael S. Tsirkin Signed-off-by: Paolo Bonzini