search for: slots_lock

...ENTFD_FLAG_PV_MMIO; /* The datamatch feature is optional, otherwise this is a wildcard */ if (args->flags & KVM_IOEVENTFD_FLAG_DATAMATCH) @@ -729,6 +747,7 @@ kvm_assign_ioeventfd(struct kvm *kvm, struct kvm_ioeventfd *args) else p->wildcard = true; + mutex_lock(&kvm->slots_lock); /* Verify that there isn't a match already */ @@ -744,12 +763,24 @@ kvm_assign_ioeventfd(struct kvm *kvm, struct kvm_ioeventfd *args) if (ret < 0) goto unlock_fail; + /* PV MMIO is also put on a separate bus, for faster lookups. + * Length is ignored for PV MMIO bus. */ + if (p...

...ENTFD_FLAG_PV_MMIO; /* The datamatch feature is optional, otherwise this is a wildcard */ if (args->flags & KVM_IOEVENTFD_FLAG_DATAMATCH) @@ -729,6 +747,7 @@ kvm_assign_ioeventfd(struct kvm *kvm, struct kvm_ioeventfd *args) else p->wildcard = true; + mutex_lock(&kvm->slots_lock); /* Verify that there isn't a match already */ @@ -744,12 +763,24 @@ kvm_assign_ioeventfd(struct kvm *kvm, struct kvm_ioeventfd *args) if (ret < 0) goto unlock_fail; + /* PV MMIO is also put on a separate bus, for faster lookups. + * Length is ignored for PV MMIO bus. */ + if (p...

...n, + false, &data); spin_unlock(&kvm->mmu_lock); /* - * kvm_mmu_slot_remove_write_access() and kvm_vm_ioctl_get_dirty_log() + * kvm_mmu_slot_apply_write_access() and kvm_vm_ioctl_get_dirty_log() * which do tlb flush out of mmu-lock should be serialized by * kvm->slots_lock otherwise tlb flush would be missed. */ @@ -5301,7 +5351,7 @@ void kvm_mmu_slot_largepage_remove_write_access(struct kvm *kvm, false, NULL); spin_unlock(&kvm->mmu_lock); - /* see kvm_mmu_slot_remove_write_access */ + /* see kvm_mmu_slot_apply_write_access*/ lockdep_assert_held...

...n, + false, &data); spin_unlock(&kvm->mmu_lock); /* - * kvm_mmu_slot_remove_write_access() and kvm_vm_ioctl_get_dirty_log() + * kvm_mmu_slot_apply_write_access() and kvm_vm_ioctl_get_dirty_log() * which do tlb flush out of mmu-lock should be serialized by * kvm->slots_lock otherwise tlb flush would be missed. */ @@ -5301,7 +5351,7 @@ void kvm_mmu_slot_largepage_remove_write_access(struct kvm *kvm, false, NULL); spin_unlock(&kvm->mmu_lock); - /* see kvm_mmu_slot_remove_write_access */ + /* see kvm_mmu_slot_apply_write_access*/ lockdep_assert_held...

Here is change log from V3 To V4: - Fixing spelling/grammar mistakes suggested by Randy Dunlap - Changing the hypercall interface to be able to process multiple pages per one hypercall also suggested by Randy Dunlap. It turns out that this will save lots of vmexist/memory slot flushes when protecting many pages. [PATCH RFC V4 1/3] KVM: X86: Memory ROE documentation [PATCH RFC V4 2/3] KVM:

Hi, This is my first set of patches that works as I would expect, and the third revision I sent to mailing lists. Following up with my previous discussions about kernel rootkit mitigation via placing R/O protection on critical data structure, static data, privileged registers with static content. These patches present the first part where it is only possible to place these protections on memory

Hi, This is my first set of patches that works as I would expect, and the third revision I sent to mailing lists. Following up with my previous discussions about kernel rootkit mitigation via placing R/O protection on critical data structure, static data, privileged registers with static content. These patches present the first part where it is only possible to place these protections on memory

...cpu); > vcpu->arch.last_host_tsc = rdtsc(); You can't call kvm_steal_time_set_preempted in atomic context (neither in sched_out notifier nor in vcpu_put() after preempt_disable)). __copy_to_user in kvm_write_guest_offset_cached schedules and locks up the host. kvm->srcu (or kvm->slots_lock) is also not taken and kvm_write_guest_offset_cached needs to call kvm_memslots which requires it. This I think is why postcopy live migration locks up with current upstream, and it doesn't seem related to userfaultfd at all (initially I suspected the vmf conversion but it wasn't that) and...

...cpu); > vcpu->arch.last_host_tsc = rdtsc(); You can't call kvm_steal_time_set_preempted in atomic context (neither in sched_out notifier nor in vcpu_put() after preempt_disable)). __copy_to_user in kvm_write_guest_offset_cached schedules and locks up the host. kvm->srcu (or kvm->slots_lock) is also not taken and kvm_write_guest_offset_cached needs to call kvm_memslots which requires it. This I think is why postcopy live migration locks up with current upstream, and it doesn't seem related to userfaultfd at all (initially I suspected the vmf conversion but it wasn't that) and...

...s up the host. > yes, you are right! :) we have known the problems. I am going to introduce something like kvm_write_guest_XXX_atomic and use them instead of kvm_write_guest_offset_cached. within pagefault_disable()/enable(), we can not call __copy_to_user I think. > kvm->srcu (or kvm->slots_lock) is also not taken and > kvm_write_guest_offset_cached needs to call kvm_memslots which > requires it. > let me check the details later. thanks for pointing it out. > This I think is why postcopy live migration locks up with current > upstream, and it doesn't seem related to use...

change from v6: fix typos and remove uncessary comments. change from v5: spilt x86/kvm patch into guest/host part. introduce kvm_write_guest_offset_cached. fix some typos. rebase patch onto 4.9.2 change from v4: spilt x86 kvm vcpu preempted check into two patches. add documentation patch. add x86 vcpu preempted check patch under xen add s390 vcpu preempted check patch change from v3:

change from v6: fix typos and remove uncessary comments. change from v5: spilt x86/kvm patch into guest/host part. introduce kvm_write_guest_offset_cached. fix some typos. rebase patch onto 4.9.2 change from v4: spilt x86 kvm vcpu preempted check into two patches. add documentation patch. add x86 vcpu preempted check patch under xen add s390 vcpu preempted check patch change from v3:

The KVM introspection subsystem provides a facility for applications running on the host or in a separate VM, to control the execution of other VM-s (pause, resume, shutdown), query the state of the vCPUs (GPRs, MSRs etc.), alter the page access bits in the shadow page tables (only for the hardware backed ones, eg. Intel's EPT) and receive notifications when events of interest have taken place

The KVM introspection subsystem provides a facility for applications running on the host or in a separate VM, to control the execution of other VM-s (pause, resume, shutdown), query the state of the vCPUs (GPRs, MSRs etc.), alter the page access bits in the shadow page tables (only for the hardware backed ones, eg. Intel's EPT) and receive notifications when events of interest have taken place