kernel.git/arch/powerpc/kvm/powerpc.c, branch linux-5.3.y

KVM: PPC: Book3S: Enable XIVE native capability only if OPAL has required functions

2019-10-11T16:35:49Z

commit 2ad7a27deaf6d78545d97ab80874584f6990360e upstream. There are some POWER9 machines where the OPAL firmware does not support the OPAL_XIVE_GET_QUEUE_STATE and OPAL_XIVE_SET_QUEUE_STATE calls. The impact of this is that a guest using XIVE natively will not be able to be migrated successfully. On the source side, the get_attr operation on the KVM native device for the KVM_DEV_XIVE_GRP_EQ_CONFIG attribute will fail; on the destination side, the set_attr operation for the same attribute will fail. This adds tests for the existence of the OPAL get/set queue state functions, and if they are not supported, the XIVE-native KVM device is not created and the KVM_CAP_PPC_IRQ_XIVE capability returns false. Userspace can then either provide a software emulation of XIVE, or else tell the guest that it does not have a XIVE controller available to it. Cc: stable@vger.kernel.org # v5.2+ Fixes: 3fab2d10588e ("KVM: PPC: Book3S HV: XIVE: Activate XIVE exploitation mode") Reviewed-by: David Gibson Reviewed-by: Cédric Le Goater Signed-off-by: Paul Mackerras Signed-off-by: Greg Kroah-Hartman

KVM: remove kvm_arch_has_vcpu_debugfs()

2019-08-05T10:55:48Z

There is no need for this function as all arches have to implement kvm_arch_create_vcpu_debugfs() no matter what. A #define symbol let us actually simplify the code. Signed-off-by: Paolo Bonzini

KVM: Fix leak vCPU's VMCS value into other pCPU

2019-08-05T10:55:47Z

After commit d73eb57b80b (KVM: Boost vCPUs that are delivering interrupts), a five years old bug is exposed. Running ebizzy benchmark in three 80 vCPUs VMs on one 80 pCPUs Skylake server, a lot of rcu_sched stall warning splatting in the VMs after stress testing: INFO: rcu_sched detected stalls on CPUs/tasks: { 4 41 57 62 77} (detected by 15, t=60004 jiffies, g=899, c=898, q=15073) Call Trace: flush_tlb_mm_range+0x68/0x140 tlb_flush_mmu.part.75+0x37/0xe0 tlb_finish_mmu+0x55/0x60 zap_page_range+0x142/0x190 SyS_madvise+0x3cd/0x9c0 system_call_fastpath+0x1c/0x21 swait_active() sustains to be true before finish_swait() is called in kvm_vcpu_block(), voluntarily preempted vCPUs are taken into account by kvm_vcpu_on_spin() loop greatly increases the probability condition kvm_arch_vcpu_runnable(vcpu) is checked and can be true, when APICv is enabled the yield-candidate vCPU's VMCS RVI field leaks(by vmx_sync_pir_to_irr()) into spinning-on-a-taken-lock vCPU's current VMCS. This patch fixes it by checking conservatively a subset of events. Cc: Paolo Bonzini Cc: Radim Krčmář Cc: Christian Borntraeger Cc: Marc Zyngier Cc: stable@vger.kernel.org Fixes: 98f4a1467 (KVM: add kvm_arch_vcpu_runnable() test to kvm_vcpu_on_spin() loop) Signed-off-by: Wanpeng Li Signed-off-by: Paolo Bonzini

Merge tag 'kvm-arm-for-5.3' of git://git.kernel.org/pub/scm/linux/kernel/git/kvmarm/kvmarm into HEAD

2019-07-11T13:14:16Z

KVM/arm updates for 5.3 - Add support for chained PMU counters in guests - Improve SError handling - Handle Neoverse N1 erratum #1349291 - Allow side-channel mitigation status to be migrated - Standardise most AArch64 system register accesses to msr_s/mrs_s - Fix host MPIDR corruption on 32bit

treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 266

2019-06-05T15:30:28Z

Based on 1 normalized pattern(s): this program is free software you can redistribute it and or modify it under the terms of the gnu general public license version 2 as published by the free software foundation this program is distributed in the hope that it will be useful but without any warranty without even the implied warranty of merchantability or fitness for a particular purpose see the gnu general public license for more details you should have received a copy of the gnu general public license along with this program if not write to the free software foundation 51 franklin street fifth floor boston ma 02110 1301 usa extracted by the scancode license scanner the SPDX license identifier GPL-2.0-only has been chosen to replace the boilerplate/reference in 67 file(s). Signed-off-by: Thomas Gleixner Reviewed-by: Allison Randal Reviewed-by: Richard Fontana Reviewed-by: Alexios Zavras Cc: linux-spdx@vger.kernel.org Link: https://lkml.kernel.org/r/20190529141333.953658117@linutronix.de Signed-off-by: Greg Kroah-Hartman

KVM: Directly return result from kvm_arch_check_processor_compat()

2019-06-04T17:27:32Z

Add a wrapper to invoke kvm_arch_check_processor_compat() so that the boilerplate ugliness of checking virtualization support on all CPUs is hidden from the arch specific code. x86's implementation in particular is quite heinous, as it unnecessarily propagates the out-param pattern into kvm_x86_ops. While the x86 specific issue could be resolved solely by changing kvm_x86_ops, make the change for all architectures as returning a value directly is prettier and technically more robust, e.g. s390 doesn't set the out param, which could lead to subtle breakage in the (highly unlikely) scenario where the out-param was not pre-initialized by the caller. Opportunistically annotate svm_check_processor_compat() with __init. Signed-off-by: Sean Christopherson Reviewed-by: Cornelia Huck Signed-off-by: Paolo Bonzini

KVM: s390: Do not report unusabled IDs via KVM_CAP_MAX_VCPU_ID

2019-05-28T13:52:19Z

KVM_CAP_MAX_VCPU_ID is currently always reporting KVM_MAX_VCPU_ID on all architectures. However, on s390x, the amount of usable CPUs is determined during runtime - it is depending on the features of the machine the code is running on. Since we are using the vcpu_id as an index into the SCA structures that are defined by the hardware (see e.g. the sca_add_vcpu() function), it is not only the amount of CPUs that is limited by the hard- ware, but also the range of IDs that we can use. Thus KVM_CAP_MAX_VCPU_ID must be determined during runtime on s390x, too. So the handling of KVM_CAP_MAX_VCPU_ID has to be moved from the common code into the architecture specific code, and on s390x we have to return the same value here as for KVM_CAP_MAX_VCPUS. This problem has been discovered with the kvm_create_max_vcpus selftest. With this change applied, the selftest now passes on s390x, too. Reviewed-by: Andrew Jones Reviewed-by: Cornelia Huck Reviewed-by: David Hildenbrand Signed-off-by: Thomas Huth Message-Id: <20190523164309.13345-9-thuth@redhat.com> Cc: stable@vger.kernel.org Signed-off-by: Christian Borntraeger

Merge tag 'kvm-ppc-next-5.2-2' of git://git.kernel.org/pub/scm/linux/kernel/git/paulus/powerpc into HEAD

2019-05-15T21:39:38Z

PPC KVM update for 5.2 * Support for guests to access the new POWER9 XIVE interrupt controller hardware directly, reducing interrupt latency and overhead for guests. * In-kernel implementation of the H_PAGE_INIT hypercall. * Reduce memory usage of sparsely-populated IOMMU tables. * Several bug fixes. Second PPC KVM update for 5.2 * Fix a bug, fix a spelling mistake, remove some useless code.

KVM: PPC: Book3S HV: XIVE: Activate XIVE exploitation mode

2019-04-30T09:35:16Z

Full support for the XIVE native exploitation mode is now available, advertise the capability KVM_CAP_PPC_IRQ_XIVE for guests running on PowerNV KVM Hypervisors only. Support for nested guests (pseries KVM Hypervisor) is not yet available. XIVE should also have been activated which is default setting on POWER9 systems running a recent Linux kernel. Signed-off-by: Cédric Le Goater Reviewed-by: David Gibson Signed-off-by: Paul Mackerras

KVM: PPC: Book3S HV: XIVE: Introduce a new capability KVM_CAP_PPC_IRQ_XIVE

2019-04-30T09:35:16Z

The user interface exposes a new capability KVM_CAP_PPC_IRQ_XIVE to let QEMU connect the vCPU presenters to the XIVE KVM device if required. The capability is not advertised for now as the full support for the XIVE native exploitation mode is not yet available. When this is case, the capability will be advertised on PowerNV Hypervisors only. Nested guests (pseries KVM Hypervisor) are not supported. Internally, the interface to the new KVM device is protected with a new interrupt mode: KVMPPC_IRQ_XIVE. Signed-off-by: Cédric Le Goater Reviewed-by: David Gibson Signed-off-by: Paul Mackerras