This series fixes some hard to produce races by introducing the use of vcpu requests. It also fixes a couple easier to produce races, ones that have been produced with the PSCI kvm-unit-test test. The easy two are addressed in two different ways: the first takes advantage of power_off having been changed to a vcpu request, the second caches vcpu MPIDRs in order to avoid extracting them from sys_regs. I've tested the series on a Mustang and a ThunderX and compile-tested the ARM bits. Patch 2/9 adds documentation, as, at least for me, understanding vcpu request interplay with vcpu kicks and vcpu mode and the memory barriers that interplay implies, is exhausting. Hopefully the document is useful to others. I'm not married to it though, so it can be deferred/dropped as people like... v2: - No longer based on Radim's vcpu request API rework[1], except for including "add kvm_request_pending" as patch 1/9 [drew] - Added vcpu request documentation [drew] - Dropped the introduction of user settable MPIDRs [Christoffer] - Added vcpu requests to all request-less vcpu kicks [Christoffer] [1] https://www.mail-archive.com/linux-kernel@xxxxxxxxxxxxxxx/msg1340496.html Andrew Jones (7): KVM: Add documentation for VCPU requests KVM: arm/arm64: prepare to use vcpu requests KVM: arm/arm64: replace vcpu->arch.pause with a vcpu request KVM: arm/arm64: replace vcpu->arch.power_off with a vcpu request KVM: arm/arm64: use a vcpu request on irq injection KVM: arm/arm64: PMU: remove request-less vcpu kick KVM: arm/arm64: avoid race by caching MPIDR Levente Kurusa (1): KVM: arm/arm64: fix race in kvm_psci_vcpu_on Radim Krčmář (1): KVM: add kvm_request_pending Documentation/virtual/kvm/vcpu-requests.rst | 114 ++++++++++++++++++++++++++++ arch/arm/include/asm/kvm_emulate.h | 2 +- arch/arm/include/asm/kvm_host.h | 13 ++-- arch/arm/kvm/arm.c | 68 +++++++++++------ arch/arm/kvm/coproc.c | 20 +++-- arch/arm/kvm/handle_exit.c | 1 + arch/arm/kvm/psci.c | 18 ++--- arch/arm64/include/asm/kvm_emulate.h | 2 +- arch/arm64/include/asm/kvm_host.h | 13 ++-- arch/arm64/kvm/handle_exit.c | 1 + arch/arm64/kvm/sys_regs.c | 27 +++---- arch/mips/kvm/trap_emul.c | 2 +- arch/powerpc/kvm/booke.c | 2 +- arch/powerpc/kvm/powerpc.c | 5 +- arch/s390/kvm/kvm-s390.c | 2 +- arch/x86/kvm/x86.c | 4 +- include/linux/kvm_host.h | 5 ++ virt/kvm/arm/arch_timer.c | 1 + virt/kvm/arm/pmu.c | 29 +++---- virt/kvm/arm/vgic/vgic.c | 12 ++- 20 files changed, 245 insertions(+), 96 deletions(-) create mode 100644 Documentation/virtual/kvm/vcpu-requests.rst -- 2.9.3