linux/arch/x86, branch v5.11-rc3

Merge tag 'x86_urgent_for_v5.11_rc3' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip

2021-01-10T19:31:17Z

Pull x86 fixes from Borislav Petkov: "As expected, fixes started trickling in after the holidays so here is the accumulated pile of x86 fixes for 5.11: - A fix for fanotify_mark() missing the conversion of x86_32 native syscalls which take 64-bit arguments to the compat handlers due to former having a general compat handler. (Brian Gerst) - Add a forgotten pmd page destructor call to pud_free_pmd_page() where a pmd page is freed. (Dan Williams) - Make IN/OUT insns with an u8 immediate port operand handling for SEV-ES guests more precise by using only the single port byte and not the whole s32 value of the insn decoder. (Peter Gonda) - Correct a straddling end range check before returning the proper MTRR type, when the end address is the same as top of memory. (Ying-Tsun Huang) - Change PQR_ASSOC MSR update scheme when moving a task to a resctrl resource group to avoid significant performance overhead with some resctrl workloads. (Fenghua Yu) - Avoid the actual task move overhead when the task is already in the resource group. (Fenghua Yu)" * tag 'x86_urgent_for_v5.11_rc3' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: x86/resctrl: Don't move a task to the same resource group x86/resctrl: Use an IPI instead of task_work_add() to update PQR_ASSOC MSR x86/mtrr: Correct the range check before performing MTRR type lookups x86/sev-es: Fix SEV-ES OUT/IN immediate opcode vc handling x86/mm: Fix leak of pmd ptlock fanotify: Fix sys_fanotify_mark() on native x86-32

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

2021-01-08T23:06:02Z

Pull kvm fixes from Paolo Bonzini: "x86: - Fixes for the new scalable MMU - Fixes for migration of nested hypervisors on AMD - Fix for clang integrated assembler - Fix for left shift by 64 (UBSAN) - Small cleanups - Straggler SEV-ES patch ARM: - VM init cleanups - PSCI relay cleanups - Kill CONFIG_KVM_ARM_PMU - Fixup __init annotations - Fixup reg_to_encoding() - Fix spurious PMCR_EL0 access Misc: - selftests cleanups" * tag 'for-linus' of git://git.kernel.org/pub/scm/virt/kvm/kvm: (38 commits) KVM: x86: __kvm_vcpu_halt can be static KVM: SVM: Add support for booting APs in an SEV-ES guest KVM: nSVM: cancel KVM_REQ_GET_NESTED_STATE_PAGES on nested vmexit KVM: nSVM: mark vmcb as dirty when forcingly leaving the guest mode KVM: nSVM: correctly restore nested_run_pending on migration KVM: x86/mmu: Clarify TDP MMU page list invariants KVM: x86/mmu: Ensure TDP MMU roots are freed after yield kvm: check tlbs_dirty directly KVM: x86: change in pv_eoi_get_pending() to make code more readable MAINTAINERS: Really update email address for Sean Christopherson KVM: x86: fix shift out of bounds reported by UBSAN KVM: selftests: Implement perf_test_util more conventionally KVM: selftests: Use vm_create_with_vcpus in create_vm KVM: selftests: Factor out guest mode code KVM/SVM: Remove leftover __svm_vcpu_run prototype from svm.c KVM: SVM: Add register operand to vmsave call in sev_es_vcpu_load KVM: x86/mmu: Optimize not-present/MMIO SPTE check in get_mmio_spte() KVM: x86/mmu: Use raw level to index into MMIO walks' sptes array KVM: x86/mmu: Get root level from walkers when retrieving MMIO SPTE KVM: x86/mmu: Use -1 to flag an undefined spte in get_mmio_spte() ...

KVM: x86: __kvm_vcpu_halt can be static

2021-01-08T10:54:44Z

Signed-off-by: Paolo Bonzini

x86/resctrl: Don't move a task to the same resource group

2021-01-08T08:08:03Z

Shakeel Butt reported in [1] that a user can request a task to be moved to a resource group even if the task is already in the group. It just wastes time to do the move operation which could be costly to send IPI to a different CPU. Add a sanity check to ensure that the move operation only happens when the task is not already in the resource group. [1] https://lore.kernel.org/lkml/CALvZod7E9zzHwenzf7objzGKsdBmVwTgEJ0nPgs0LUFU3SN5Pw@mail.gmail.com/ Fixes: e02737d5b826 ("x86/intel_rdt: Add tasks files") Reported-by: Shakeel Butt Signed-off-by: Fenghua Yu Signed-off-by: Reinette Chatre Signed-off-by: Borislav Petkov Reviewed-by: Tony Luck Cc: stable@vger.kernel.org Link: https://lkml.kernel.org/r/962ede65d8e95be793cb61102cca37f7bb018e66.1608243147.git.reinette.chatre@intel.com

x86/resctrl: Use an IPI instead of task_work_add() to update PQR_ASSOC MSR

2021-01-08T08:03:36Z

Currently, when moving a task to a resource group the PQR_ASSOC MSR is updated with the new closid and rmid in an added task callback. If the task is running, the work is run as soon as possible. If the task is not running, the work is executed later in the kernel exit path when the kernel returns to the task again. Updating the PQR_ASSOC MSR as soon as possible on the CPU a moved task is running is the right thing to do. Queueing work for a task that is not running is unnecessary (the PQR_ASSOC MSR is already updated when the task is scheduled in) and causing system resource waste with the way in which it is implemented: Work to update the PQR_ASSOC register is queued every time the user writes a task id to the "tasks" file, even if the task already belongs to the resource group. This could result in multiple pending work items associated with a single task even if they are all identical and even though only a single update with most recent values is needed. Specifically, even if a task is moved between different resource groups while it is sleeping then it is only the last move that is relevant but yet a work item is queued during each move. This unnecessary queueing of work items could result in significant system resource waste, especially on tasks sleeping for a long time. For example, as demonstrated by Shakeel Butt in [1] writing the same task id to the "tasks" file can quickly consume significant memory. The same problem (wasted system resources) occurs when moving a task between different resource groups. As pointed out by Valentin Schneider in [2] there is an additional issue with the way in which the queueing of work is done in that the task_struct update is currently done after the work is queued, resulting in a race with the register update possibly done before the data needed by the update is available. To solve these issues, update the PQR_ASSOC MSR in a synchronous way right after the new closid and rmid are ready during the task movement, only if the task is running. If a moved task is not running nothing is done since the PQR_ASSOC MSR will be updated next time the task is scheduled. This is the same way used to update the register when tasks are moved as part of resource group removal. [1] https://lore.kernel.org/lkml/CALvZod7E9zzHwenzf7objzGKsdBmVwTgEJ0nPgs0LUFU3SN5Pw@mail.gmail.com/ [2] https://lore.kernel.org/lkml/20201123022433.17905-1-valentin.schneider@arm.com [ bp: Massage commit message and drop the two update_task_closid_rmid() variants. ] Fixes: e02737d5b826 ("x86/intel_rdt: Add tasks files") Reported-by: Shakeel Butt Reported-by: Valentin Schneider Signed-off-by: Fenghua Yu Signed-off-by: Reinette Chatre Signed-off-by: Borislav Petkov Reviewed-by: Tony Luck Reviewed-by: James Morse Reviewed-by: Valentin Schneider Cc: stable@vger.kernel.org Link: https://lkml.kernel.org/r/17aa2fb38fc12ce7bb710106b3e7c7b45acb9e94.1608243147.git.reinette.chatre@intel.com

KVM: SVM: Add support for booting APs in an SEV-ES guest

2021-01-07T23:11:37Z

Typically under KVM, an AP is booted using the INIT-SIPI-SIPI sequence, where the guest vCPU register state is updated and then the vCPU is VMRUN to begin execution of the AP. For an SEV-ES guest, this won't work because the guest register state is encrypted. Following the GHCB specification, the hypervisor must not alter the guest register state, so KVM must track an AP/vCPU boot. Should the guest want to park the AP, it must use the AP Reset Hold exit event in place of, for example, a HLT loop. First AP boot (first INIT-SIPI-SIPI sequence): Execute the AP (vCPU) as it was initialized and measured by the SEV-ES support. It is up to the guest to transfer control of the AP to the proper location. Subsequent AP boot: KVM will expect to receive an AP Reset Hold exit event indicating that the vCPU is being parked and will require an INIT-SIPI-SIPI sequence to awaken it. When the AP Reset Hold exit event is received, KVM will place the vCPU into a simulated HLT mode. Upon receiving the INIT-SIPI-SIPI sequence, KVM will make the vCPU runnable. It is again up to the guest to then transfer control of the AP to the proper location. To differentiate between an actual HLT and an AP Reset Hold, a new MP state is introduced, KVM_MP_STATE_AP_RESET_HOLD, which the vCPU is placed in upon receiving the AP Reset Hold exit event. Additionally, to communicate the AP Reset Hold exit event up to userspace (if needed), a new exit reason is introduced, KVM_EXIT_AP_RESET_HOLD. A new x86 ops function is introduced, vcpu_deliver_sipi_vector, in order to accomplish AP booting. For VMX, vcpu_deliver_sipi_vector is set to the original SIPI delivery function, kvm_vcpu_deliver_sipi_vector(). SVM adds a new function that, for non SEV-ES guests, invokes the original SIPI delivery function, kvm_vcpu_deliver_sipi_vector(), but for SEV-ES guests, implements the logic above. Signed-off-by: Tom Lendacky Message-Id: Signed-off-by: Paolo Bonzini

KVM: nSVM: cancel KVM_REQ_GET_NESTED_STATE_PAGES on nested vmexit

2021-01-07T23:11:35Z

It is possible to exit the nested guest mode, entered by svm_set_nested_state prior to first vm entry to it (e.g due to pending event) if the nested run was not pending during the migration. In this case we must not switch to the nested msr permission bitmap. Also add a warning to catch similar cases in the future. Fixes: a7d5c7ce41ac1 ("KVM: nSVM: delay MSR permission processing to first nested VM run") Signed-off-by: Maxim Levitsky Message-Id: <20210107093854.882483-2-mlevitsk@redhat.com> Signed-off-by: Paolo Bonzini

KVM: nSVM: mark vmcb as dirty when forcingly leaving the guest mode

2021-01-07T23:11:34Z

We overwrite most of vmcb fields while doing so, so we must mark it as dirty. Signed-off-by: Maxim Levitsky Message-Id: <20210107093854.882483-5-mlevitsk@redhat.com> Signed-off-by: Paolo Bonzini

KVM: nSVM: correctly restore nested_run_pending on migration

2021-01-07T23:11:33Z

The code to store it on the migration exists, but no code was restoring it. One of the side effects of fixing this is that L1->L2 injected events are no longer lost when migration happens with nested run pending. Signed-off-by: Maxim Levitsky Message-Id: <20210107093854.882483-3-mlevitsk@redhat.com> Signed-off-by: Paolo Bonzini

KVM: x86/mmu: Clarify TDP MMU page list invariants

2021-01-07T23:11:32Z

The tdp_mmu_roots and tdp_mmu_pages in struct kvm_arch should only contain pages with tdp_mmu_page set to true. tdp_mmu_pages should not contain any pages with a non-zero root_count and tdp_mmu_roots should only contain pages with a positive root_count, unless a thread holds the MMU lock and is in the process of modifying the list. Various functions expect these invariants to be maintained, but they are not explictily documented. Add to the comments on both fields to document the above invariants. Signed-off-by: Ben Gardon Message-Id: <20210107001935.3732070-2-bgardon@google.com> Signed-off-by: Paolo Bonzini