linux-dev/arch/powerpc/kvm/powerpc.c, branch linus/master

Merge branch 'topic/ppc-kvm' into next

2022-05-19T13:10:42Z

Merge our KVM topic branch.

KVM: PPC: Book3S HV: Use IDA allocator for LPID allocator

2022-05-13T11:33:33Z

This removes the fixed-size lpid_inuse array. Signed-off-by: Nicholas Piggin Reviewed-by: Fabiano Rosas Signed-off-by: Michael Ellerman Link: https://lore.kernel.org/r/20220123120043.3586018-4-npiggin@gmail.com

KVM: PPC: Remove kvmppc_claim_lpid

2022-05-13T11:33:33Z

Removing kvmppc_claim_lpid makes the lpid allocator API a bit simpler to change the underlying implementation in a future patch. The host LPID is always 0, so that can be a detail of the allocator. If the allocator range is restricted, that can reserve LPIDs at the top of the range. This allows kvmppc_claim_lpid to be removed. Signed-off-by: Michael Ellerman Link: https://lore.kernel.org/r/20220123120043.3586018-2-npiggin@gmail.com

powerpc: Add missing headers

2022-05-08T12:15:40Z

Don't inherit headers "by chances" from asm/prom.h, asm/mpc52xx.h, asm/pci.h etc... Include the needed headers, and remove asm/prom.h when it was needed exclusively for pulling necessary headers. Signed-off-by: Christophe Leroy Signed-off-by: Michael Ellerman Link: https://lore.kernel.org/r/be8bdc934d152a7d8ee8d1a840d5596e2f7d85e0.1646767214.git.christophe.leroy@csgroup.eu

KVM: Add helpers to wrap vcpu->srcu_idx and yell if it's abused

2022-04-21T17:16:11Z

Add wrappers to acquire/release KVM's SRCU lock when stashing the index in vcpu->src_idx, along with rudimentary detection of illegal usage, e.g. re-acquiring SRCU and thus overwriting vcpu->src_idx. Because the SRCU index is (currently) either 0 or 1, illegal nesting bugs can go unnoticed for quite some time and only cause problems when the nested lock happens to get a different index. Wrap the WARNs in PROVE_RCU=y, and make them ONCE, otherwise KVM will likely yell so loudly that it will bring the kernel to its knees. Signed-off-by: Sean Christopherson Tested-by: Fabiano Rosas Message-Id: <20220415004343.2203171-4-seanjc@google.com> Signed-off-by: Paolo Bonzini

KVM: PPC: Use KVM_CAP_PPC_AIL_MODE_3

2022-03-08T02:14:01Z

Use KVM_CAP_PPC_AIL_MODE_3 to advertise the capability to set the AIL resource mode to 3 with the H_SET_MODE hypercall. This capability differs between processor types and KVM types (PR, HV, Nested HV), and affects guest-visible behaviour. QEMU will implement a cap-ail-mode-3 to control this behaviour[1], and use the KVM CAP if available to determine KVM support[2]. [1] https://lists.nongnu.org/archive/html/qemu-ppc/2022-02/msg00437.html [2] https://lists.nongnu.org/archive/html/qemu-ppc/2022-02/msg00439.html Signed-off-by: Nicholas Piggin Reviewed-by: Fabiano Rosas [mpe: Rebase onto 93b71801a827 from kvm-ppc-cap-210 branch, add EXPORT_SYMBOL] Signed-off-by: Michael Ellerman Link: https://lore.kernel.org/r/20220222064727.2314380-4-npiggin@gmail.com

KVM: PPC: Decrement module refcount if init_vm fails

2022-02-03T05:50:44Z

We increment the reference count for KVM-HV/PR before the call to kvmppc_core_init_vm. If that function fails we need to decrement the refcount. Also remove the check on kvm_ops->owner because try_module_get can handle a NULL module. Signed-off-by: Fabiano Rosas Reviewed-by: Nicholas Piggin Signed-off-by: Michael Ellerman Link: https://lore.kernel.org/r/20220125155735.1018683-5-farosas@linux.ibm.com

KVM: PPC: Merge powerpc's debugfs entry content into generic entry

2022-02-02T09:30:26Z

At the moment KVM on PPC creates 4 types of entries under the kvm debugfs: 1) "%pid-%fd" per a KVM instance (for all platforms); 2) "vm%pid" (for PPC Book3s HV KVM); 3) "vm%u_vcpu%u_timing" (for PPC Book3e KVM); 4) "kvm-xive-%p" (for XIVE PPC Book3s KVM, the same for XICS); The problem with this is that multiple VMs per process is not allowed for 2) and 3) which makes it possible for userspace to trigger errors when creating duplicated debugfs entries. This merges all these into 1). This defines kvm_arch_create_kvm_debugfs() similar to kvm_arch_create_vcpu_debugfs(). This defines 2 hooks in kvmppc_ops that allow specific KVM implementations add necessary entries, this adds the _e500 suffix to kvmppc_create_vcpu_debugfs_e500() to make it clear what platform it is for. This makes use of already existing kvm_arch_create_vcpu_debugfs() on PPC. This removes no more used debugfs_dir pointers from PPC kvm_arch structs. This stops removing vcpu entries as once created vcpus stay around for the entire life of a VM and removed when the KVM instance is closed, see commit d56f5136b010 ("KVM: let kvm_destroy_vm_debugfs clean up vCPU debugfs directories"). Suggested-by: Fabiano Rosas Signed-off-by: Alexey Kardashevskiy Reviewed-by: Cédric Le Goater Signed-off-by: Michael Ellerman Link: https://lore.kernel.org/r/20220111005404.162219-1-aik@ozlabs.ru

KVM: PPC: Book3s: mmio: Deliver DSI after emulation failure

2022-01-31T02:43:00Z

MMIO emulation can fail if the guest uses an instruction that we are not prepared to emulate. Since these instructions can be and most likely are valid ones, this is (slightly) closer to an access fault than to an illegal instruction, so deliver a Data Storage interrupt instead of a Program interrupt. BookE ignores bad faults, so it will keep using a Program interrupt because a DSI would cause a fault loop in the guest. Suggested-by: Nicholas Piggin Signed-off-by: Fabiano Rosas Reviewed-by: Nicholas Piggin Signed-off-by: Michael Ellerman Link: https://lore.kernel.org/r/20220125215655.1026224-6-farosas@linux.ibm.com

KVM: PPC: mmio: Return to guest after emulation failure

2022-01-31T02:43:00Z

If MMIO emulation fails we don't want to crash the whole guest by returning to userspace. The original commit bbf45ba57eae ("KVM: ppc: PowerPC 440 KVM implementation") added a todo: /* XXX Deliver Program interrupt to guest. */ and later the commit d69614a295ae ("KVM: PPC: Separate loadstore emulation from priv emulation") added the Program interrupt injection but in another file, so I'm assuming it was missed that this block needed to be altered. Also change the message to a ratelimited one since we're letting the guest run and it could flood the host logs. Signed-off-by: Fabiano Rosas Reviewed-by: Nicholas Piggin Signed-off-by: Michael Ellerman Link: https://lore.kernel.org/r/20220125215655.1026224-5-farosas@linux.ibm.com