linux/virt/kvm, branch v3.19

kvm: warn on more invariant breakage

2014-12-28T09:01:25Z

Modifying a non-existent slot is not allowed. Also check that the first loop doesn't move a deleted slot beyond the used part of the mslots array. Signed-off-by: Paolo Bonzini

kvm: fix sorting of memslots with base_gfn == 0

2014-12-28T09:01:17Z

Before commit 0e60b0799fed (kvm: change memslot sorting rule from size to GFN, 2014-12-01), the memslots' sorting key was npages, meaning that a valid memslot couldn't have its sorting key equal to zero. On the other hand, a valid memslot can have base_gfn == 0, and invalid memslots are identified by base_gfn == npages == 0. Because of this, commit 0e60b0799fed broke the invariant that invalid memslots are at the end of the mslots array. When a memslot with base_gfn == 0 was created, any invalid memslot before it were left in place. This can be fixed by changing the insertion to use a ">=" comparison instead of "<=", but some care is needed to avoid breaking the case of deleting a memslot; see the comment in update_memslots. Thanks to Tiejun Chen for posting an initial patch for this bug. Reported-by: Jamie Heilman Reported-by: Andy Lutomirski Tested-by: Jamie Heilman Signed-off-by: Paolo Bonzini

Merge tag 'for-linus' of git://git.kernel.org/pub/scm/virt/kvm/kvm

2014-12-19T00:05:28Z

Pull KVM update from Paolo Bonzini: "3.19 changes for KVM: - spring cleaning: removed support for IA64, and for hardware- assisted virtualization on the PPC970 - ARM, PPC, s390 all had only small fixes For x86: - small performance improvements (though only on weird guests) - usual round of hardware-compliancy fixes from Nadav - APICv fixes - XSAVES support for hosts and guests. XSAVES hosts were broken because the (non-KVM) XSAVES patches inadvertently changed the KVM userspace ABI whenever XSAVES was enabled; hence, this part is going to stable. Guest support is just a matter of exposing the feature and CPUID leaves support" * tag 'for-linus' of git://git.kernel.org/pub/scm/virt/kvm/kvm: (179 commits) KVM: move APIC types to arch/x86/ KVM: PPC: Book3S: Enable in-kernel XICS emulation by default KVM: PPC: Book3S HV: Improve H_CONFER implementation KVM: PPC: Book3S HV: Fix endianness of instruction obtained from HEIR register KVM: PPC: Book3S HV: Remove code for PPC970 processors KVM: PPC: Book3S HV: Tracepoints for KVM HV guest interactions KVM: PPC: Book3S HV: Simplify locking around stolen time calculations arch: powerpc: kvm: book3s_paired_singles.c: Remove unused function arch: powerpc: kvm: book3s_pr.c: Remove unused function arch: powerpc: kvm: book3s.c: Remove some unused functions arch: powerpc: kvm: book3s_32_mmu.c: Remove unused function KVM: PPC: Book3S HV: Check wait conditions before sleeping in kvmppc_vcore_blocked KVM: PPC: Book3S HV: ptes are big endian KVM: PPC: Book3S HV: Fix inaccuracies in ICP emulation for H_IPI KVM: PPC: Book3S HV: Fix KSM memory corruption KVM: PPC: Book3S HV: Fix an issue where guest is paused on receiving HMI KVM: PPC: Book3S HV: Fix computation of tlbie operand KVM: PPC: Book3S HV: Add missing HPTE unlock KVM: PPC: BookE: Improve irq inject tracepoint arm/arm64: KVM: Require in-kernel vgic for the arch timers ...

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: Require in-kernel vgic for the arch timers

2014-12-15T10:50:42Z

It is curently possible to run a VM with architected timers support without creating an in-kernel VGIC, which will result in interrupts from the virtual timer going nowhere. To address this issue, move the architected timers initialization to the time when we run a VCPU for the first time, and then only initialize (and enable) the architected timers if we have a properly created and initialized in-kernel VGIC. When injecting interrupts from the virtual timer to the vgic, the current setup should ensure that this never calls an on-demand init of the VGIC, which is the only call path that could return an error from kvm_vgic_inject_irq(), so capture the return value and raise a warning if there's an error there. We also change the kvm_timer_init() function from returning an int to be a void function, since the function always succeeds. Reviewed-by: Marc Zyngier Signed-off-by: Christoffer Dall

arm/arm64: KVM: Initialize the vgic on-demand when injecting IRQs

2014-12-15T10:36:21Z

Userspace assumes that it can wire up IRQ injections after having created all VCPUs and after having created the VGIC, but potentially before starting the first VCPU. This can currently lead to lost IRQs because the state of that IRQ injection is not stored anywhere and we don't return an error to userspace. We haven't seen this problem manifest itself yet, presumably because guests reset the devices on boot, but this could cause issues with migration and other non-standard startup configurations. Reviewed-by: Marc Zyngier Signed-off-by: Christoffer Dall

arm/arm64: KVM: Add (new) vgic_initialized macro

2014-12-13T13:17:10Z

Some code paths will need to check to see if the internal state of the vgic has been initialized (such as when creating new VCPUs), so introduce such a macro that checks the nr_cpus field which is set when the vgic has been initialized. Also set nr_cpus = 0 in kvm_vgic_destroy, because the error path in vgic_init() will call this function, and code should never errornously assume the vgic to be properly initialized after an error. Acked-by: Marc Zyngier Reviewed-by: Eric Auger Signed-off-by: Christoffer Dall

arm/arm64: KVM: Rename vgic_initialized to vgic_ready

2014-12-13T13:17:05Z

The vgic_initialized() macro currently returns the state of the vgic->ready flag, which indicates if the vgic is ready to be used when running a VM, not specifically if its internal state has been initialized. Rename the macro accordingly in preparation for a more nuanced initialization flow. Acked-by: Marc Zyngier Reviewed-by: Eric Auger Signed-off-by: Christoffer Dall

arm/arm64: KVM: vgic: move reset initialization into vgic_init_maps()

2014-12-13T13:15:52Z

VGIC initialization currently happens in three phases: (1) kvm_vgic_create() (triggered by userspace GIC creation) (2) vgic_init_maps() (triggered by userspace GIC register read/write requests, or from kvm_vgic_init() if not already run) (3) kvm_vgic_init() (triggered by first VM run) We were doing initialization of some state to correspond with the state of a freshly-reset GIC in kvm_vgic_init(); this is too late, since it will overwrite changes made by userspace using the register access APIs before the VM is run. Move this initialization earlier, into the vgic_init_maps() phase. This fixes a bug where QEMU could successfully restore a saved VM state snapshot into a VM that had already been run, but could not restore it "from cold" using the -loadvm command line option (the symptoms being that the restored VM would run but interrupts were ignored). Finally rename vgic_init_maps to vgic_init and renamed kvm_vgic_init to kvm_vgic_map_resources. [ This patch is originally written by Peter Maydell, but I have modified it somewhat heavily, renaming various bits and moving code around. If something is broken, I am to be blamed. - Christoffer ] Acked-by: Marc Zyngier Reviewed-by: Eric Auger Signed-off-by: Peter Maydell Signed-off-by: Christoffer Dall

KVM: track pid for VCPU only on KVM_RUN ioctl

2014-12-04T14:29:13Z

We currently track the pid of the task that runs the VCPU in vcpu_load. If a yield to that VCPU is triggered while the PID of the wrong thread is active, the wrong thread might receive a yield, but this will most likely not help the executing thread at all. Instead, if we only track the pid on the KVM_RUN ioctl, there are two possibilities: 1) the thread that did a non-KVM_RUN ioctl is holding a mutex that the VCPU thread is waiting for. In this case, the VCPU thread is not runnable, but we also do not do a wrong yield. 2) the thread that did a non-KVM_RUN ioctl is sleeping, or doing something that does not block the VCPU thread. In this case, the VCPU thread can receive the directed yield correctly. Signed-off-by: Christian Borntraeger CC: Rik van Riel CC: Raghavendra K T CC: Michael Mueller Signed-off-by: Paolo Bonzini