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2018-10-09KVM: PPC: Book3S HV: Use XICS hypercalls when running as a nested hypervisorPaul Mackerras
This adds code to call the H_IPI and H_EOI hypercalls when we are running as a nested hypervisor (i.e. without the CPU_FTR_HVMODE cpu feature) and we would otherwise access the XICS interrupt controller directly or via an OPAL call. Reviewed-by: David Gibson <david@gibson.dropbear.id.au> Signed-off-by: Paul Mackerras <paulus@ozlabs.org> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2018-10-09KVM: PPC: Book3S HV: Nested guest entry via hypercallPaul Mackerras
This adds a new hypercall, H_ENTER_NESTED, which is used by a nested hypervisor to enter one of its nested guests. The hypercall supplies register values in two structs. Those values are copied by the level 0 (L0) hypervisor (the one which is running in hypervisor mode) into the vcpu struct of the L1 guest, and then the guest is run until an interrupt or error occurs which needs to be reported to L1 via the hypercall return value. Currently this assumes that the L0 and L1 hypervisors are the same endianness, and the structs passed as arguments are in native endianness. If they are of different endianness, the version number check will fail and the hcall will be rejected. Nested hypervisors do not support indep_threads_mode=N, so this adds code to print a warning message if the administrator has set indep_threads_mode=N, and treat it as Y. Reviewed-by: David Gibson <david@gibson.dropbear.id.au> Signed-off-by: Paul Mackerras <paulus@ozlabs.org> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2018-10-09KVM: PPC: Book3S HV: Framework and hcall stubs for nested virtualizationPaul Mackerras
This starts the process of adding the code to support nested HV-style virtualization. It defines a new H_SET_PARTITION_TABLE hypercall which a nested hypervisor can use to set the base address and size of a partition table in its memory (analogous to the PTCR register). On the host (level 0 hypervisor) side, the H_SET_PARTITION_TABLE hypercall from the guest is handled by code that saves the virtual PTCR value for the guest. This also adds code for creating and destroying nested guests and for reading the partition table entry for a nested guest from L1 memory. Each nested guest has its own shadow LPID value, different in general from the LPID value used by the nested hypervisor to refer to it. The shadow LPID value is allocated at nested guest creation time. Nested hypervisor functionality is only available for a radix guest, which therefore means a radix host on a POWER9 (or later) processor. Signed-off-by: Paul Mackerras <paulus@ozlabs.org> Reviewed-by: David Gibson <david@gibson.dropbear.id.au> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2018-10-09KVM: PPC: Book3S HV: Use kvmppc_unmap_pte() in kvm_unmap_radix()Paul Mackerras
kvmppc_unmap_pte() does a sequence of operations that are open-coded in kvm_unmap_radix(). This extends kvmppc_unmap_pte() a little so that it can be used by kvm_unmap_radix(), and makes kvm_unmap_radix() call it. Reviewed-by: David Gibson <david@gibson.dropbear.id.au> Signed-off-by: Paul Mackerras <paulus@ozlabs.org> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2018-10-09KVM: PPC: Book3S HV: Refactor radix page fault handlerSuraj Jitindar Singh
The radix page fault handler accounts for all cases, including just needing to insert a pte. This breaks it up into separate functions for the two main cases; setting rc and inserting a pte. This allows us to make the setting of rc and inserting of a pte generic for any pgtable, not specific to the one for this guest. [paulus@ozlabs.org - reduced diffs from previous code] Reviewed-by: David Gibson <david@gibson.dropbear.id.au> Signed-off-by: Suraj Jitindar Singh <sjitindarsingh@gmail.com> Signed-off-by: Paul Mackerras <paulus@ozlabs.org> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2018-10-09KVM: PPC: Book3S HV: Make kvmppc_mmu_radix_xlate process/partition table ↵Suraj Jitindar Singh
agnostic kvmppc_mmu_radix_xlate() is used to translate an effective address through the process tables. The process table and partition tables have identical layout. Exploit this fact to make the kvmppc_mmu_radix_xlate() function able to translate either an effective address through the process tables or a guest real address through the partition tables. [paulus@ozlabs.org - reduced diffs from previous code] Reviewed-by: David Gibson <david@gibson.dropbear.id.au> Signed-off-by: Suraj Jitindar Singh <sjitindarsingh@gmail.com> Signed-off-by: Paul Mackerras <paulus@ozlabs.org> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2018-10-09KVM: PPC: Book3S HV: Clear partition table entry on vm teardownSuraj Jitindar Singh
When destroying a VM we return the LPID to the pool, however we never zero the partition table entry. This is instead done when we reallocate the LPID. Zero the partition table entry on VM teardown before returning the LPID to the pool. This means if we were running as a nested hypervisor the real hypervisor could use this to determine when it can free resources. Reviewed-by: David Gibson <david@gibson.dropbear.id.au> Signed-off-by: Suraj Jitindar Singh <sjitindarsingh@gmail.com> Signed-off-by: Paul Mackerras <paulus@ozlabs.org> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2018-10-09KVM: PPC: Use ccr field in pt_regs struct embedded in vcpu structPaul Mackerras
When the 'regs' field was added to struct kvm_vcpu_arch, the code was changed to use several of the fields inside regs (e.g., gpr, lr, etc.) but not the ccr field, because the ccr field in struct pt_regs is 64 bits on 64-bit platforms, but the cr field in kvm_vcpu_arch is only 32 bits. This changes the code to use the regs.ccr field instead of cr, and changes the assembly code on 64-bit platforms to use 64-bit loads and stores instead of 32-bit ones. Reviewed-by: David Gibson <david@gibson.dropbear.id.au> Signed-off-by: Paul Mackerras <paulus@ozlabs.org> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2018-10-09KVM: PPC: Book3S HV: Add a debugfs file to dump radix mappingsPaul Mackerras
This adds a file called 'radix' in the debugfs directory for the guest, which when read gives all of the valid leaf PTEs in the partition-scoped radix tree for a radix guest, in human-readable format. It is analogous to the existing 'htab' file which dumps the HPT entries for a HPT guest. Reviewed-by: David Gibson <david@gibson.dropbear.id.au> Signed-off-by: Paul Mackerras <paulus@ozlabs.org> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2018-10-09KVM: PPC: Book3S HV: Handle hypervisor instruction faults betterPaul Mackerras
Currently the code for handling hypervisor instruction page faults passes 0 for the flags indicating the type of fault, which is OK in the usual case that the page is not mapped in the partition-scoped page tables. However, there are other causes for hypervisor instruction page faults, such as not being to update a reference (R) or change (C) bit. The cause is indicated in bits in HSRR1, including a bit which indicates that the fault is due to not being able to write to a page (for example to update an R or C bit). Not handling these other kinds of faults correctly can lead to a loop of continual faults without forward progress in the guest. In order to handle these faults better, this patch constructs a "DSISR-like" value from the bits which DSISR and SRR1 (for a HISI) have in common, and passes it to kvmppc_book3s_hv_page_fault() so that it knows what caused the fault. Reviewed-by: David Gibson <david@gibson.dropbear.id.au> Signed-off-by: Paul Mackerras <paulus@ozlabs.org> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2018-10-09KVM: PPC: Book3S HV: Streamlined guest entry/exit path on P9 for radix guestsPaul Mackerras
This creates an alternative guest entry/exit path which is used for radix guests on POWER9 systems when we have indep_threads_mode=Y. In these circumstances there is exactly one vcpu per vcore and there is no coordination required between vcpus or vcores; the vcpu can enter the guest without needing to synchronize with anything else. The new fast path is implemented almost entirely in C in book3s_hv.c and runs with the MMU on until the guest is entered. On guest exit we use the existing path until the point where we are committed to exiting the guest (as distinct from handling an interrupt in the low-level code and returning to the guest) and we have pulled the guest context from the XIVE. At that point we check a flag in the stack frame to see whether we came in via the old path and the new path; if we came in via the new path then we go back to C code to do the rest of the process of saving the guest context and restoring the host context. The C code is split into separate functions for handling the OS-accessible state and the hypervisor state, with the idea that the latter can be replaced by a hypercall when we implement nested virtualization. Signed-off-by: Paul Mackerras <paulus@ozlabs.org> Reviewed-by: David Gibson <david@gibson.dropbear.id.au> [mpe: Fix CONFIG_ALTIVEC=n build] Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2018-10-09KVM: PPC: Book3S HV: Call kvmppc_handle_exit_hv() with vcore unlockedPaul Mackerras
Currently kvmppc_handle_exit_hv() is called with the vcore lock held because it is called within a for_each_runnable_thread loop. However, we already unlock the vcore within kvmppc_handle_exit_hv() under certain circumstances, and this is safe because (a) any vcpus that become runnable and are added to the runnable set by kvmppc_run_vcpu() have their vcpu->arch.trap == 0 and can't actually run in the guest (because the vcore state is VCORE_EXITING), and (b) for_each_runnable_thread is safe against addition or removal of vcpus from the runnable set. Therefore, in order to simplify things for following patches, let's drop the vcore lock in the for_each_runnable_thread loop, so kvmppc_handle_exit_hv() gets called without the vcore lock held. Reviewed-by: David Gibson <david@gibson.dropbear.id.au> Signed-off-by: Paul Mackerras <paulus@ozlabs.org> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2018-10-09KVM: PPC: Book3S: Rework TM save/restore code and make it C-callablePaul Mackerras
This adds a parameter to __kvmppc_save_tm and __kvmppc_restore_tm which allows the caller to indicate whether it wants the nonvolatile register state to be preserved across the call, as required by the C calling conventions. This parameter being non-zero also causes the MSR bits that enable TM, FP, VMX and VSX to be preserved. The condition register and DSCR are now always preserved. With this, kvmppc_save_tm_hv and kvmppc_restore_tm_hv can be called from C code provided the 3rd parameter is non-zero. So that these functions can be called from modules, they now include code to set the TOC pointer (r2) on entry, as they can call other built-in C functions which will assume the TOC to have been set. Also, the fake suspend code in kvmppc_save_tm_hv is modified here to assume that treclaim in fake-suspend state does not modify any registers, which is the case on POWER9. This enables the code to be simplified quite a bit. _kvmppc_save_tm_pr and _kvmppc_restore_tm_pr become much simpler with this change, since they now only need to save and restore TAR and pass 1 for the 3rd argument to __kvmppc_{save,restore}_tm. Reviewed-by: David Gibson <david@gibson.dropbear.id.au> Signed-off-by: Paul Mackerras <paulus@ozlabs.org> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2018-10-09KVM: PPC: Book3S HV: Simplify real-mode interrupt handlingPaul Mackerras
This streamlines the first part of the code that handles a hypervisor interrupt that occurred in the guest. With this, all of the real-mode handling that occurs is done before the "guest_exit_cont" label; once we get to that label we are committed to exiting to host virtual mode. Thus the machine check and HMI real-mode handling is moved before that label. Also, the code to handle external interrupts is moved out of line, as is the code that calls kvmppc_realmode_hmi_handler(). Signed-off-by: Paul Mackerras <paulus@ozlabs.org> Reviewed-by: David Gibson <david@gibson.dropbear.id.au> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2018-10-09KVM: PPC: Book3S HV: Extract PMU save/restore operations as C-callable functionsPaul Mackerras
This pulls out the assembler code that is responsible for saving and restoring the PMU state for the host and guest into separate functions so they can be used from an alternate entry path. The calling convention is made compatible with C. Reviewed-by: David Gibson <david@gibson.dropbear.id.au> Signed-off-by: Paul Mackerras <paulus@ozlabs.org> Reviewed-by: Madhavan Srinivasan <maddy@linux.vnet.ibm.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2018-10-09KVM: PPC: Book3S HV: Move interrupt delivery on guest entry to C codePaul Mackerras
This is based on a patch by Suraj Jitindar Singh. This moves the code in book3s_hv_rmhandlers.S that generates an external, decrementer or privileged doorbell interrupt just before entering the guest to C code in book3s_hv_builtin.c. This is to make future maintenance and modification easier. The algorithm expressed in the C code is almost identical to the previous algorithm. Reviewed-by: David Gibson <david@gibson.dropbear.id.au> Signed-off-by: Paul Mackerras <paulus@ozlabs.org> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2018-10-09KVM: PPC: Book3S HV: Remove left-over code in XICS-on-XIVE emulationPaul Mackerras
This removes code that clears the external interrupt pending bit in the pending_exceptions bitmap. This is left over from an earlier iteration of the code where this bit was set when an escalation interrupt arrived in order to wake the vcpu from cede. Currently we set the vcpu->arch.irq_pending flag instead for this purpose. Therefore there is no need to do anything with the pending_exceptions bitmap. Reviewed-by: David Gibson <david@gibson.dropbear.id.au> Signed-off-by: Paul Mackerras <paulus@ozlabs.org> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2018-10-09KVM: PPC: Book3S: Simplify external interrupt handlingPaul Mackerras
Currently we use two bits in the vcpu pending_exceptions bitmap to indicate that an external interrupt is pending for the guest, one for "one-shot" interrupts that are cleared when delivered, and one for interrupts that persist until cleared by an explicit action of the OS (e.g. an acknowledge to an interrupt controller). The BOOK3S_IRQPRIO_EXTERNAL bit is used for one-shot interrupt requests and BOOK3S_IRQPRIO_EXTERNAL_LEVEL is used for persisting interrupts. In practice BOOK3S_IRQPRIO_EXTERNAL never gets used, because our Book3S platforms generally, and pseries in particular, expect external interrupt requests to persist until they are acknowledged at the interrupt controller. That combined with the confusion introduced by having two bits for what is essentially the same thing makes it attractive to simplify things by only using one bit. This patch does that. With this patch there is only BOOK3S_IRQPRIO_EXTERNAL, and by default it has the semantics of a persisting interrupt. In order to avoid breaking the ABI, we introduce a new "external_oneshot" flag which preserves the behaviour of the KVM_INTERRUPT ioctl with the KVM_INTERRUPT_SET argument. Reviewed-by: David Gibson <david@gibson.dropbear.id.au> Signed-off-by: Paul Mackerras <paulus@ozlabs.org> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2018-10-09powerpc: Turn off CPU_FTR_P9_TM_HV_ASSIST in non-hypervisor modePaul Mackerras
When doing nested virtualization, it is only necessary to do the transactional memory hypervisor assist at level 0, that is, when we are in hypervisor mode. Nested hypervisors can just use the TM facilities as architected. Therefore we should clear the CPU_FTR_P9_TM_HV_ASSIST bit when we are not in hypervisor mode, along with the CPU_FTR_HVMODE bit. Doing this will not change anything at this stage because the only code that tests CPU_FTR_P9_TM_HV_ASSIST is in HV KVM, which currently can only be used when when CPU_FTR_HVMODE is set. Reviewed-by: David Gibson <david@gibson.dropbear.id.au> Signed-off-by: Paul Mackerras <paulus@ozlabs.org> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2018-10-09KVM: PPC: Remove redundand permission bits removalAlexey Kardashevskiy
The kvmppc_gpa_to_ua() helper itself takes care of the permission bits in the TCE and yet every single caller removes them. This changes semantics of kvmppc_gpa_to_ua() so it takes TCEs (which are GPAs + TCE permission bits) to make the callers simpler. This should cause no behavioural change. Signed-off-by: Alexey Kardashevskiy <aik@ozlabs.ru> Reviewed-by: David Gibson <david@gibson.dropbear.id.au> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2018-10-09KVM: PPC: Propagate errors to the guest when failed instead of ignoringAlexey Kardashevskiy
At the moment if the PUT_TCE{_INDIRECT} handlers fail to update the hardware tables, we print a warning once, clear the entry and continue. This is so as at the time the assumption was that if a VFIO device is hotplugged into the guest, and the userspace replays virtual DMA mappings (i.e. TCEs) to the hardware tables and if this fails, then there is nothing useful we can do about it. However the assumption is not valid as these handlers are not called for TCE replay (VFIO ioctl interface is used for that) and these handlers are for new TCEs. This returns an error to the guest if there is a request which cannot be processed. By now the only possible failure must be H_TOO_HARD. Signed-off-by: Alexey Kardashevskiy <aik@ozlabs.ru> Reviewed-by: David Gibson <david@gibson.dropbear.id.au> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2018-10-09KVM: PPC: Validate TCEs against preregistered memory page sizesAlexey Kardashevskiy
The userspace can request an arbitrary supported page size for a DMA window and this works fine as long as the mapped memory is backed with the pages of the same or bigger size; if this is not the case, mm_iommu_ua_to_hpa{_rm}() fail and tables do not populated with dangerously incorrect TCEs. However since it is quite easy to misconfigure the KVM and we do not do reverts to all changes made to TCE tables if an error happens in a middle, we better do the acceptable page size validation before we even touch the tables. This enhances kvmppc_tce_validate() to check the hardware IOMMU page sizes against the preregistered memory page sizes. Since the new check uses real/virtual mode helpers, this renames kvmppc_tce_validate() to kvmppc_rm_tce_validate() to handle the real mode case and mirrors it for the virtual mode under the old name. The real mode handler is not used for the virtual mode as: 1. it uses _lockless() list traversing primitives instead of RCU; 2. realmode's mm_iommu_ua_to_hpa_rm() uses vmalloc_to_phys() which virtual mode does not have to use and since on POWER9+radix only virtual mode handlers actually work, we do not want to slow down that path even a bit. This removes EXPORT_SYMBOL_GPL(kvmppc_tce_validate) as the validators are static now. From now on the attempts on mapping IOMMU pages bigger than allowed will result in KVM exit. Signed-off-by: Alexey Kardashevskiy <aik@ozlabs.ru> Reviewed-by: David Gibson <david@gibson.dropbear.id.au> [mpe: Fix KVM_HV=n build] Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2018-10-08Merge branch 'apv11' of ↵Christian Borntraeger
git://git.kernel.org/pub/scm/linux/kernel/git/kvms390/linux into kernelorgnext
2018-10-08s390: vfio-ap: make local functions and data staticChristian Borntraeger
no functional change, just hygiene. Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com> Reviewed-by: Cornelia Huck <cohuck@redhat.com> Reviewed-by: David Hildenbrand <david@redhat.com>
2018-10-05s390: vfio-ap: setup APCB mask using KVM dedicated functionPierre Morel
We replace the vfio_ap_mdev_copy_masks() by the new kvm_arch_crypto_set_masks() to be able to use the standard KVM tracing system. Signed-off-by: Pierre Morel <pmorel@linux.ibm.com> Message-Id: <1538728270-10340-3-git-send-email-pmorel@linux.ibm.com> Reviewed-by: Cornelia Huck <cohuck@redhat.com> Reviewed-by: David Hildenbrand <david@redhat.com> Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com>
2018-10-05KVM: s390: Tracing APCB changesPierre Morel
kvm_arch_crypto_set_masks is a new function to centralize the setup the APCB masks inside the CRYCB SIE satellite. To trace APCB mask changes, we add KVM_EVENT() tracing to both kvm_arch_crypto_set_masks and kvm_arch_crypto_clear_masks. Signed-off-by: Pierre Morel <pmorel@linux.ibm.com> Message-Id: <1538728270-10340-2-git-send-email-pmorel@linux.ibm.com> Reviewed-by: Cornelia Huck <cohuck@redhat.com> Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com>
2018-10-05KVM: s390: fix locking for crypto setting error pathChristian Borntraeger
We need to unlock the kvm->lock mutex in the error case. Reported-by: smatch Fixes: 37940fb0b6a2c4bf101 ("KVM: s390: device attrs to enable/disable AP interpretation") Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com> Reviewed-by: Janosch Frank <frankja@linux.ibm.com> Reviewed-by: Pierre Morel <pmorel@linux.ibm.com> Reviewed-by: David Hildenbrand <david@redhat.com> Reviewed-by: Cornelia Huck <cohuck@redhat.com> Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com>
2018-10-05KVM: PPC: Book3S HV: Provide mode where all vCPUs on a core must be the same VMPaul Mackerras
This adds a mode where the vcore scheduling logic in HV KVM limits itself to scheduling only virtual cores from the same VM on any given physical core. This is enabled via a new module parameter on the kvm-hv module called "one_vm_per_core". For this to work on POWER9, it is necessary to set indep_threads_mode=N. (On POWER8, hardware limitations mean that KVM is never in independent threads mode, regardless of the indep_threads_mode setting.) Thus the settings needed for this to work are: 1. The host is in SMT1 mode. 2. On POWER8, the host is not in 2-way or 4-way static split-core mode. 3. On POWER9, the indep_threads_mode parameter is N. 4. The one_vm_per_core parameter is Y. With these settings, KVM can run up to 4 vcpus on a core at the same time on POWER9, or up to 8 vcpus on POWER8 (depending on the guest threading mode), and will ensure that all of the vcpus belong to the same VM. This is intended for use in security-conscious settings where users are concerned about possible side-channel attacks between threads which could perhaps enable one VM to attack another VM on the same core, or the host. Signed-off-by: Paul Mackerras <paulus@ozlabs.org>
2018-10-05KVM: PPC: Book3S PR: Exiting split hack mode needs to fixup both PC and LRCameron Kaiser
When an OS (currently only classic Mac OS) is running in KVM-PR and makes a linked jump from code with split hack addressing enabled into code that does not, LR is not correctly updated and reflects the previously munged PC. To fix this, this patch undoes the address munge when exiting split hack mode so that code relying on LR being a proper address will now execute. This does not affect OS X or other operating systems running on KVM-PR. Signed-off-by: Cameron Kaiser <spectre@floodgap.com> Signed-off-by: Paul Mackerras <paulus@ozlabs.org>
2018-10-04Merge tag 'kvm-s390-next-4.20-1' of ↵Paolo Bonzini
git://git.kernel.org/pub/scm/linux/kernel/git/kvms390/linux into HEAD KVM: s390: Features for 4.20 - Initial version of AP crypto virtualization via vfio-mdev - Set the host program identifier - Optimize page table locking
2018-10-04kvm: nVMX: fix entry with pending interrupt if APICv is enabledPaolo Bonzini
Commit b5861e5cf2fcf83031ea3e26b0a69d887adf7d21 introduced a check on the interrupt-window and NMI-window CPU execution controls in order to inject an external interrupt vmexit before the first guest instruction executes. However, when APIC virtualization is enabled the host does not need a vmexit in order to inject an interrupt at the next interrupt window; instead, it just places the interrupt vector in RVI and the processor will inject it as soon as possible. Therefore, on machines with APICv it is not enough to check the CPU execution controls: the same scenario can also happen if RVI>vPPR. Fixes: b5861e5cf2fcf83031ea3e26b0a69d887adf7d21 Reviewed-by: Nikita Leshchenko <nikita.leshchenko@oracle.com> Cc: Sean Christopherson <sean.j.christopherson@intel.com> Cc: Liran Alon <liran.alon@oracle.com> Cc: Radim Krčmář <rkrcmar@redhat.com> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2018-10-04KVM: VMX: hide flexpriority from guest when disabled at the module levelPaolo Bonzini
As of commit 8d860bbeedef ("kvm: vmx: Basic APIC virtualization controls have three settings"), KVM will disable VIRTUALIZE_APIC_ACCESSES when a nested guest writes APIC_BASE MSR and kvm-intel.flexpriority=0, whereas previously KVM would allow a nested guest to enable VIRTUALIZE_APIC_ACCESSES so long as it's supported in hardware. That is, KVM now advertises VIRTUALIZE_APIC_ACCESSES to a guest but doesn't (always) allow setting it when kvm-intel.flexpriority=0, and may even initially allow the control and then clear it when the nested guest writes APIC_BASE MSR, which is decidedly odd even if it doesn't cause functional issues. Hide the control completely when the module parameter is cleared. reported-by: Sean Christopherson <sean.j.christopherson@intel.com> Fixes: 8d860bbeedef ("kvm: vmx: Basic APIC virtualization controls have three settings") Cc: Jim Mattson <jmattson@google.com> Cc: stable@vger.kernel.org Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2018-10-04KVM: VMX: check for existence of secondary exec controls before accessingSean Christopherson
Return early from vmx_set_virtual_apic_mode() if the processor doesn't support VIRTUALIZE_APIC_ACCESSES or VIRTUALIZE_X2APIC_MODE, both of which reside in SECONDARY_VM_EXEC_CONTROL. This eliminates warnings due to VMWRITEs to SECONDARY_VM_EXEC_CONTROL (VMCS field 401e) failing on processors without secondary exec controls. Remove the similar check for TPR shadowing as it is incorporated in the flexpriority_enabled check and the APIC-related code in vmx_update_msr_bitmap() is further gated by VIRTUALIZE_X2APIC_MODE. Reported-by: Gerhard Wiesinger <redhat@wiesinger.com> Fixes: 8d860bbeedef ("kvm: vmx: Basic APIC virtualization controls have three settings") Cc: Jim Mattson <jmattson@google.com> Cc: stable@vger.kernel.org Signed-off-by: Sean Christopherson <sean.j.christopherson@intel.com> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2018-10-02KVM: PPC: Inform the userspace about TCE update failuresAlexey Kardashevskiy
We return H_TOO_HARD from TCE update handlers when we think that the next handler (realmode -> virtual mode -> user mode) has a chance to handle the request; H_HARDWARE/H_CLOSED otherwise. This changes the handlers to return H_TOO_HARD on every error giving the userspace an opportunity to handle any request or at least log them all. Signed-off-by: Alexey Kardashevskiy <aik@ozlabs.ru> Reviewed-by: David Gibson <david@gibson.dropbear.id.au> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2018-10-02KVM: PPC: Validate all tces before updating tablesAlexey Kardashevskiy
The KVM TCE handlers are written in a way so they fail when either something went horribly wrong or the userspace did some obvious mistake such as passing a misaligned address. We are going to enhance the TCE checker to fail on attempts to map bigger IOMMU page than the underlying pinned memory so let's valitate TCE beforehand. This should cause no behavioral change. Signed-off-by: Alexey Kardashevskiy <aik@ozlabs.ru> Reviewed-by: David Gibson <david@gibson.dropbear.id.au> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2018-10-02Merge branch 'kvm-ppc-fixes' of paulus/powerpc into topic/ppc-kvmMichael Ellerman
Some commits we'd like to share between the powerpc and kvm-ppc tree for next have dependencies on commits that went into 4.19 via the kvm-ppc-fixes branch and weren't merged before 4.19-rc3, which is our base commit. So merge the kvm-ppc-fixes branch into topic/ppc-kvm.
2018-10-01KVM: x86: fix L1TF's MMIO GFN calculationSean Christopherson
One defense against L1TF in KVM is to always set the upper five bits of the *legal* physical address in the SPTEs for non-present and reserved SPTEs, e.g. MMIO SPTEs. In the MMIO case, the GFN of the MMIO SPTE may overlap with the upper five bits that are being usurped to defend against L1TF. To preserve the GFN, the bits of the GFN that overlap with the repurposed bits are shifted left into the reserved bits, i.e. the GFN in the SPTE will be split into high and low parts. When retrieving the GFN from the MMIO SPTE, e.g. to check for an MMIO access, get_mmio_spte_gfn() unshifts the affected bits and restores the original GFN for comparison. Unfortunately, get_mmio_spte_gfn() neglects to mask off the reserved bits in the SPTE that were used to store the upper chunk of the GFN. As a result, KVM fails to detect MMIO accesses whose GPA overlaps the repurprosed bits, which in turn causes guest panics and hangs. Fix the bug by generating a mask that covers the lower chunk of the GFN, i.e. the bits that aren't shifted by the L1TF mitigation. The alternative approach would be to explicitly zero the five reserved bits that are used to store the upper chunk of the GFN, but that requires additional run-time computation and makes an already-ugly bit of code even more inscrutable. I considered adding a WARN_ON_ONCE(low_phys_bits-1 <= PAGE_SHIFT) to warn if GENMASK_ULL() generated a nonsensical value, but that seemed silly since that would mean a system that supports VMX has less than 18 bits of physical address space... Reported-by: Sakari Ailus <sakari.ailus@iki.fi> Fixes: d9b47449c1a1 ("kvm: x86: Set highest physical address bits in non-present/reserved SPTEs") Cc: Junaid Shahid <junaids@google.com> Cc: Jim Mattson <jmattson@google.com> Cc: stable@vger.kernel.org Reviewed-by: Junaid Shahid <junaids@google.com> Tested-by: Sakari Ailus <sakari.ailus@linux.intel.com> Signed-off-by: Sean Christopherson <sean.j.christopherson@intel.com> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2018-10-01tools/kvm_stat: cut down decimal places in update interval dialogStefan Raspl
We currently display the default number of decimal places for floats in _show_set_update_interval(), which is quite pointless. Cutting down to a single decimal place. Signed-off-by: Stefan Raspl <raspl@linux.ibm.com> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2018-10-01KVM: nVMX: Fix emulation of VM_ENTRY_LOAD_BNDCFGSLiran Alon
L2 IA32_BNDCFGS should be updated with vmcs12->guest_bndcfgs only when VM_ENTRY_LOAD_BNDCFGS is specified in vmcs12->vm_entry_controls. Otherwise, L2 IA32_BNDCFGS should be set to vmcs01->guest_bndcfgs which is L1 IA32_BNDCFGS. Reviewed-by: Nikita Leshchenko <nikita.leshchenko@oracle.com> Reviewed-by: Darren Kenny <darren.kenny@oracle.com> Signed-off-by: Liran Alon <liran.alon@oracle.com> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2018-10-01KVM: x86: Do not use kvm_x86_ops->mpx_supported() directlyLiran Alon
Commit a87036add092 ("KVM: x86: disable MPX if host did not enable MPX XSAVE features") introduced kvm_mpx_supported() to return true iff MPX is enabled in the host. However, that commit seems to have missed replacing some calls to kvm_x86_ops->mpx_supported() to kvm_mpx_supported(). Complete original commit by replacing remaining calls to kvm_mpx_supported(). Fixes: a87036add092 ("KVM: x86: disable MPX if host did not enable MPX XSAVE features") Suggested-by: Sean Christopherson <sean.j.christopherson@intel.com> Signed-off-by: Liran Alon <liran.alon@oracle.com> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2018-10-01KVM: nVMX: Do not expose MPX VMX controls when guest MPX disabledLiran Alon
Before this commit, KVM exposes MPX VMX controls to L1 guest only based on if KVM and host processor supports MPX virtualization. However, these controls should be exposed to guest only in case guest vCPU supports MPX. Without this change, a L1 guest running with kernel which don't have commit 691bd4340bef ("kvm: vmx: allow host to access guest MSR_IA32_BNDCFGS") asserts in QEMU on the following: qemu-kvm: error: failed to set MSR 0xd90 to 0x0 qemu-kvm: .../qemu-2.10.0/target/i386/kvm.c:1801 kvm_put_msrs: Assertion 'ret == cpu->kvm_msr_buf->nmsrs failed' This is because L1 KVM kvm_init_msr_list() will see that vmx_mpx_supported() (As it only checks MPX VMX controls support) and therefore KVM_GET_MSR_INDEX_LIST IOCTL will include MSR_IA32_BNDCFGS. However, later when L1 will attempt to set this MSR via KVM_SET_MSRS IOCTL, it will fail because !guest_cpuid_has_mpx(vcpu). Therefore, fix the issue by exposing MPX VMX controls to L1 guest only when vCPU supports MPX. Fixes: 36be0b9deb23 ("KVM: x86: Add nested virtualization support for MPX") Reported-by: Eyal Moscovici <eyal.moscovici@oracle.com> Reviewed-by: Nikita Leshchenko <nikita.leshchenko@oracle.com> Reviewed-by: Darren Kenny <darren.kenny@oracle.com> Signed-off-by: Liran Alon <liran.alon@oracle.com> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2018-10-01Merge branch 'apv11' of ↵Christian Borntraeger
git://git.kernel.org/pub/scm/linux/kernel/git/kvms390/linux into kernelorgnext
2018-10-01s390/mm: optimize locking without huge pages in gmap_pmd_op_walk()David Hildenbrand
Right now we temporarily take the page table lock in gmap_pmd_op_walk() even though we know we won't need it (if we can never have 1mb pages mapped into the gmap). Let's make this a special case, so gmap_protect_range() and gmap_sync_dirty_log_pmd() will not take the lock when huge pages are not allowed. gmap_protect_range() is called quite frequently for managing shadow page tables in vSIE environments. Signed-off-by: David Hildenbrand <david@redhat.com> Reviewed-by: Janosch Frank <frankja@linux.ibm.com> Message-Id: <20180806155407.15252-1-david@redhat.com> Signed-off-by: Janosch Frank <frankja@linux.ibm.com>
2018-10-01KVM: s390: set host program identifierCollin Walling
A host program identifier (HPID) provides information regarding the underlying host environment. A level-2 (VM) guest will have an HPID denoting Linux/KVM, which is set during VCPU setup. A level-3 (VM on a VM) and beyond guest will have an HPID denoting KVM vSIE, which is set for all shadow control blocks, overriding the original value of the HPID. Signed-off-by: Collin Walling <walling@linux.ibm.com> Reviewed-by: Janosch Frank <frankja@linux.ibm.com> Message-Id: <1535734279-10204-4-git-send-email-walling@linux.ibm.com> Reviewed-by: Christian Borntraeger <borntraeger@de.ibm.com> Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com>
2018-09-28s390: doc: detailed specifications for AP virtualizationTony Krowiak
This patch provides documentation describing the AP architecture and design concepts behind the virtualization of AP devices. It also includes an example of how to configure AP devices for exclusive use of KVM guests. Signed-off-by: Tony Krowiak <akrowiak@linux.ibm.com> Reviewed-by: Halil Pasic <pasic@linux.ibm.com> Message-Id: <20180925231641.4954-27-akrowiak@linux.vnet.ibm.com> Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com>
2018-09-28KVM: s390: CPU model support for AP virtualizationTony Krowiak
Introduces two new CPU model facilities to support AP virtualization for KVM guests: 1. AP Query Configuration Information (QCI) facility is installed. This is indicated by setting facilities bit 12 for the guest. The kernel will not enable this facility for the guest if it is not set on the host. If this facility is not set for the KVM guest, then only APQNs with an APQI less than 16 will be used by a Linux guest regardless of the matrix configuration for the virtual machine. This is a limitation of the Linux AP bus. 2. AP Facilities Test facility (APFT) is installed. This is indicated by setting facilities bit 15 for the guest. The kernel will not enable this facility for the guest if it is not set on the host. If this facility is not set for the KVM guest, then no AP devices will be available to the guest regardless of the guest's matrix configuration for the virtual machine. This is a limitation of the Linux AP bus. Signed-off-by: Tony Krowiak <akrowiak@linux.ibm.com> Reviewed-by: Christian Borntraeger <borntraeger@de.ibm.com> Reviewed-by: Halil Pasic <pasic@linux.ibm.com> Reviewed-by: David Hildenbrand <david@redhat.com> Tested-by: Michael Mueller <mimu@linux.ibm.com> Tested-by: Farhan Ali <alifm@linux.ibm.com> Acked-by: Cornelia Huck <cohuck@redhat.com> Message-Id: <20180925231641.4954-26-akrowiak@linux.vnet.ibm.com> Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com>
2018-09-28KVM: s390: device attrs to enable/disable AP interpretationTony Krowiak
Introduces two new VM crypto device attributes (KVM_S390_VM_CRYPTO) to enable or disable AP instruction interpretation from userspace via the KVM_SET_DEVICE_ATTR ioctl: * The KVM_S390_VM_CRYPTO_ENABLE_APIE attribute enables hardware interpretation of AP instructions executed on the guest. * The KVM_S390_VM_CRYPTO_DISABLE_APIE attribute disables hardware interpretation of AP instructions executed on the guest. In this case the instructions will be intercepted and pass through to the guest. Signed-off-by: Tony Krowiak <akrowiak@linux.ibm.com> Reviewed-by: Cornelia Huck <cohuck@redhat.com> Message-Id: <20180925231641.4954-25-akrowiak@linux.vnet.ibm.com> Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com>
2018-09-28KVM: s390: vsie: allow guest FORMAT-0 CRYCB on host FORMAT-2Pierre Morel
When the guest schedules a SIE with a FORMAT-0 CRYCB, we are able to schedule it in the host with a FORMAT-2 CRYCB if the host uses FORMAT-2 Signed-off-by: Pierre Morel <pmorel@linux.ibm.com> Signed-off-by: Tony Krowiak <akrowiak@linux.ibm.com> Message-Id: <20180925231641.4954-24-akrowiak@linux.vnet.ibm.com> Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com>
2018-09-28KVM: s390: vsie: allow guest FORMAT-1 CRYCB on host FORMAT-2Pierre Morel
When the guest schedules a SIE with a CRYCB FORMAT-1 CRYCB, we are able to schedule it in the host with a FORMAT-2 CRYCB if the host uses FORMAT-2. Signed-off-by: Pierre Morel <pmorel@linux.ibm.com> Signed-off-by: Tony Krowiak <akrowiak@linux.ibm.com> Message-Id: <20180925231641.4954-23-akrowiak@linux.vnet.ibm.com> Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com>
2018-09-28KVM: s390: vsie: allow guest FORMAT-0 CRYCB on host FORMAT-1Pierre Morel
When the guest schedules a SIE with a FORMAT-0 CRYCB, we are able to schedule it in the host with a FORMAT-1 CRYCB if the host uses FORMAT-1 or FORMAT-0. Signed-off-by: Pierre Morel <pmorel@linux.ibm.com> Signed-off-by: Tony Krowiak <akrowiak@linux.ibm.com> Message-Id: <20180925231641.4954-22-akrowiak@linux.vnet.ibm.com> Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com>