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2018-11-27KVM: nVMX/nSVM: Fix bug which sets vcpu->arch.tsc_offset to L1 tsc_offsetLeonid Shatz
Since commit e79f245ddec1 ("X86/KVM: Properly update 'tsc_offset' to represent the running guest"), vcpu->arch.tsc_offset meaning was changed to always reflect the tsc_offset value set on active VMCS. Regardless if vCPU is currently running L1 or L2. However, above mentioned commit failed to also change kvm_vcpu_write_tsc_offset() to set vcpu->arch.tsc_offset correctly. This is because vmx_write_tsc_offset() could set the tsc_offset value in active VMCS to given offset parameter *plus vmcs12->tsc_offset*. However, kvm_vcpu_write_tsc_offset() just sets vcpu->arch.tsc_offset to given offset parameter. Without taking into account the possible addition of vmcs12->tsc_offset. (Same is true for SVM case). Fix this issue by changing kvm_x86_ops->write_tsc_offset() to return actually set tsc_offset in active VMCS and modify kvm_vcpu_write_tsc_offset() to set returned value in vcpu->arch.tsc_offset. In addition, rename write_tsc_offset() callback to write_l1_tsc_offset() to make it clear that it is meant to set L1 TSC offset. Fixes: e79f245ddec1 ("X86/KVM: Properly update 'tsc_offset' to represent the running guest") Reviewed-by: Liran Alon <liran.alon@oracle.com> Reviewed-by: Mihai Carabas <mihai.carabas@oracle.com> Reviewed-by: Krish Sadhukhan <krish.sadhukhan@oracle.com> Signed-off-by: Leonid Shatz <leonid.shatz@oracle.com> Cc: stable@vger.kernel.org Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2018-11-27svm: Add mutex_lock to protect apic_access_page_done on AMD systemsWei Wang
There is a race condition when accessing kvm->arch.apic_access_page_done. Due to it, x86_set_memory_region will fail when creating the second vcpu for a svm guest. Add a mutex_lock to serialize the accesses to apic_access_page_done. This lock is also used by vmx for the same purpose. Signed-off-by: Wei Wang <wawei@amazon.de> Signed-off-by: Amadeusz Juskowiak <ajusk@amazon.de> Signed-off-by: Julian Stecklina <jsteckli@amazon.de> Signed-off-by: Suravee Suthikulpanit <suravee.suthikulpanit@amd.com> Reviewed-by: Joerg Roedel <jroedel@suse.de> Cc: stable@vger.kernel.org Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2018-10-25Merge tag 'kvm-4.20-1' of git://git.kernel.org/pub/scm/virt/kvm/kvmLinus Torvalds
Pull KVM updates from Radim Krčmář: "ARM: - Improved guest IPA space support (32 to 52 bits) - RAS event delivery for 32bit - PMU fixes - Guest entry hardening - Various cleanups - Port of dirty_log_test selftest PPC: - Nested HV KVM support for radix guests on POWER9. The performance is much better than with PR KVM. Migration and arbitrary level of nesting is supported. - Disable nested HV-KVM on early POWER9 chips that need a particular hardware bug workaround - One VM per core mode to prevent potential data leaks - PCI pass-through optimization - merge ppc-kvm topic branch and kvm-ppc-fixes to get a better base s390: - Initial version of AP crypto virtualization via vfio-mdev - Improvement for vfio-ap - Set the host program identifier - Optimize page table locking x86: - Enable nested virtualization by default - Implement Hyper-V IPI hypercalls - Improve #PF and #DB handling - Allow guests to use Enlightened VMCS - Add migration selftests for VMCS and Enlightened VMCS - Allow coalesced PIO accesses - Add an option to perform nested VMCS host state consistency check through hardware - Automatic tuning of lapic_timer_advance_ns - Many fixes, minor improvements, and cleanups" * tag 'kvm-4.20-1' of git://git.kernel.org/pub/scm/virt/kvm/kvm: (204 commits) KVM/nVMX: Do not validate that posted_intr_desc_addr is page aligned Revert "kvm: x86: optimize dr6 restore" KVM: PPC: Optimize clearing TCEs for sparse tables x86/kvm/nVMX: tweak shadow fields selftests/kvm: add missing executables to .gitignore KVM: arm64: Safety check PSTATE when entering guest and handle IL KVM: PPC: Book3S HV: Don't use streamlined entry path on early POWER9 chips arm/arm64: KVM: Enable 32 bits kvm vcpu events support arm/arm64: KVM: Rename function kvm_arch_dev_ioctl_check_extension() KVM: arm64: Fix caching of host MDCR_EL2 value KVM: VMX: enable nested virtualization by default KVM/x86: Use 32bit xor to clear registers in svm.c kvm: x86: Introduce KVM_CAP_EXCEPTION_PAYLOAD kvm: vmx: Defer setting of DR6 until #DB delivery kvm: x86: Defer setting of CR2 until #PF delivery kvm: x86: Add payload operands to kvm_multiple_exception kvm: x86: Add exception payload fields to kvm_vcpu_events kvm: x86: Add has_payload and payload to kvm_queued_exception KVM: Documentation: Fix omission in struct kvm_vcpu_events KVM: selftests: add Enlightened VMCS test ...
2018-10-17KVM/x86: Use 32bit xor to clear registers in svm.cUros Bizjak
x86_64 zero-extends 32bit xor operation to a full 64bit register. Also add a comment and remove unnecessary instruction suffix in vmx.c Signed-off-by: Uros Bizjak <ubizjak@gmail.com> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2018-10-17kvm: x86: Defer setting of CR2 until #PF deliveryJim Mattson
When exception payloads are enabled by userspace (which is not yet possible) and a #PF is raised in L2, defer the setting of CR2 until the #PF is delivered. This allows the L1 hypervisor to intercept the fault before CR2 is modified. For backwards compatibility, when exception payloads are not enabled by userspace, kvm_multiple_exception modifies CR2 when the #PF exception is raised. Reported-by: Jim Mattson <jmattson@google.com> Suggested-by: Paolo Bonzini <pbonzini@redhat.com> Signed-off-by: Jim Mattson <jmattson@google.com> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2018-10-17KVM: nVMX: add KVM_CAP_HYPERV_ENLIGHTENED_VMCS capabilityVitaly Kuznetsov
Enlightened VMCS is opt-in. The current version does not contain all fields supported by nested VMX so we must not advertise the corresponding VMX features if enlightened VMCS is enabled. Userspace is given the enlightened VMCS version supported by KVM as part of enabling KVM_CAP_HYPERV_ENLIGHTENED_VMCS. The version is to be advertised to the nested hypervisor, currently done via a cpuid leaf for Hyper-V. Suggested-by: Ladi Prosek <lprosek@redhat.com> Signed-off-by: Vitaly Kuznetsov <vkuznets@redhat.com> Reviewed-by: Liran Alon <liran.alon@oracle.com> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2018-10-17x86/kvm/mmu: make vcpu->mmu a pointer to the current MMUVitaly Kuznetsov
As a preparation to full MMU split between L1 and L2 make vcpu->arch.mmu a pointer to the currently used mmu. For now, this is always vcpu->arch.root_mmu. No functional change. Signed-off-by: Vitaly Kuznetsov <vkuznets@redhat.com> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com> Reviewed-by: Sean Christopherson <sean.j.christopherson@intel.com>
2018-10-09KVM: x86: support CONFIG_KVM_AMD=y with CONFIG_CRYPTO_DEV_CCP_DD=mPaolo Bonzini
SEV requires access to the AMD cryptographic device APIs, and this does not work when KVM is builtin and the crypto driver is a module. Actually the Kconfig conditions for CONFIG_KVM_AMD_SEV try to disable SEV in that case, but it does not work because the actual crypto calls are not culled, only sev_hardware_setup() is. This patch adds two CONFIG_KVM_AMD_SEV checks that gate all the remaining SEV code; it fixes this particular configuration, and drops 5 KiB of code when CONFIG_KVM_AMD_SEV=n. Reported-by: Guenter Roeck <linux@roeck-us.net> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2018-09-20KVM: VMX: use preemption timer to force immediate VMExitSean Christopherson
A VMX preemption timer value of '0' is guaranteed to cause a VMExit prior to the CPU executing any instructions in the guest. Use the preemption timer (if it's supported) to trigger immediate VMExit in place of the current method of sending a self-IPI. This ensures that pending VMExit injection to L1 occurs prior to executing any instructions in the guest (regardless of nesting level). When deferring VMExit injection, KVM generates an immediate VMExit from the (possibly nested) guest by sending itself an IPI. Because hardware interrupts are blocked prior to VMEnter and are unblocked (in hardware) after VMEnter, this results in taking a VMExit(INTR) before any guest instruction is executed. But, as this approach relies on the IPI being received before VMEnter executes, it only works as intended when KVM is running as L0. Because there are no architectural guarantees regarding when IPIs are delivered, when running nested the INTR may "arrive" long after L2 is running e.g. L0 KVM doesn't force an immediate switch to L1 to deliver an INTR. For the most part, this unintended delay is not an issue since the events being injected to L1 also do not have architectural guarantees regarding their timing. The notable exception is the VMX preemption timer[1], which is architecturally guaranteed to cause a VMExit prior to executing any instructions in the guest if the timer value is '0' at VMEnter. Specifically, the delay in injecting the VMExit causes the preemption timer KVM unit test to fail when run in a nested guest. Note: this approach is viable even on CPUs with a broken preemption timer, as broken in this context only means the timer counts at the wrong rate. There are no known errata affecting timer value of '0'. [1] I/O SMIs also have guarantees on when they arrive, but I have no idea if/how those are emulated in KVM. Signed-off-by: Sean Christopherson <sean.j.christopherson@intel.com> [Use a hook for SVM instead of leaving the default in x86.c - Paolo] Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2018-09-20KVM: SVM: Switch to bitmap_zalloc()Andy Shevchenko
Switch to bitmap_zalloc() to show clearly what we are allocating. Besides that it returns pointer of bitmap type instead of opaque void *. Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2018-08-30KVM: x86: Rename emulate_instruction() to kvm_emulate_instruction()Sean Christopherson
Lack of the kvm_ prefix gives the impression that it's a VMX or SVM specific function, and there's no conflict that prevents adding the kvm_ prefix. Signed-off-by: Sean Christopherson <sean.j.christopherson@intel.com> Signed-off-by: Radim Krčmář <rkrcmar@redhat.com>
2018-08-30KVM: x86: SVM: Set EMULTYPE_NO_REEXECUTE for RSM emulationSean Christopherson
Re-execution after an emulation decode failure is only intended to handle a case where two or vCPUs race to write a shadowed page, i.e. we should never re-execute an instruction as part of RSM emulation. Add a new helper, kvm_emulate_instruction_from_buffer(), to support emulating from a pre-defined buffer. This eliminates the last direct call to x86_emulate_instruction() outside of kvm_mmu_page_fault(), which means x86_emulate_instruction() can be unexported in a future patch. Fixes: 7607b7174405 ("KVM: SVM: install RSM intercept") Cc: Brijesh Singh <brijesh.singh@amd.com> Signed-off-by: Sean Christopherson <sean.j.christopherson@intel.com> Cc: stable@vger.kernel.org Signed-off-by: Radim Krčmář <rkrcmar@redhat.com>
2018-08-30KVM: SVM: remove unused variable dst_vaddr_endColin Ian King
Variable dst_vaddr_end is being assigned but is never used hence it is redundant and can be removed. Cleans up clang warning: variable 'dst_vaddr_end' set but not used [-Wunused-but-set-variable] Signed-off-by: Colin Ian King <colin.king@canonical.com> Signed-off-by: Radim Krčmář <rkrcmar@redhat.com>
2018-08-22KVM: x86: SVM: Call x86_spec_ctrl_set_guest/host() with interrupts disabledThomas Gleixner
Mikhail reported the following lockdep splat: WARNING: possible irq lock inversion dependency detected CPU 0/KVM/10284 just changed the state of lock: 000000000d538a88 (&st->lock){+...}, at: speculative_store_bypass_update+0x10b/0x170 but this lock was taken by another, HARDIRQ-safe lock in the past: (&(&sighand->siglock)->rlock){-.-.} and interrupts could create inverse lock ordering between them. Possible interrupt unsafe locking scenario: CPU0 CPU1 ---- ---- lock(&st->lock); local_irq_disable(); lock(&(&sighand->siglock)->rlock); lock(&st->lock); <Interrupt> lock(&(&sighand->siglock)->rlock); *** DEADLOCK *** The code path which connects those locks is: speculative_store_bypass_update() ssb_prctl_set() do_seccomp() do_syscall_64() In svm_vcpu_run() speculative_store_bypass_update() is called with interupts enabled via x86_virt_spec_ctrl_set_guest/host(). This is actually a false positive, because GIF=0 so interrupts are disabled even if IF=1; however, we can easily move the invocations of x86_virt_spec_ctrl_set_guest/host() into the interrupt disabled region to cure it, and it's a good idea to keep the GIF=0/IF=1 area as small and self-contained as possible. Fixes: 1f50ddb4f418 ("x86/speculation: Handle HT correctly on AMD") Reported-by: Mikhail Gavrilov <mikhail.v.gavrilov@gmail.com> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Tested-by: Mikhail Gavrilov <mikhail.v.gavrilov@gmail.com> Cc: Joerg Roedel <joro@8bytes.org> Cc: Paolo Bonzini <pbonzini@redhat.com> Cc: Radim Krčmář <rkrcmar@redhat.com> Cc: Matthew Wilcox <willy@infradead.org> Cc: Borislav Petkov <bp@suse.de> Cc: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com> Cc: Tom Lendacky <thomas.lendacky@amd.com> Cc: kvm@vger.kernel.org Cc: x86@kernel.org Cc: stable@vger.kernel.org Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2018-08-06kvm: x86: Flush only affected TLB entries in kvm_mmu_invlpg*Junaid Shahid
This needs a minor bug fix. The updated patch is as follows. Thanks, Junaid ------------------------------------------------------------------------------ kvm_mmu_invlpg() and kvm_mmu_invpcid_gva() only need to flush the TLB entries for the specific guest virtual address, instead of flushing all TLB entries associated with the VM. Signed-off-by: Junaid Shahid <junaids@google.com> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2018-08-06kvm: x86: Add ability to skip TLB flush when switching CR3Junaid Shahid
Remove the implicit flush from the set_cr3 handlers, so that the callers are able to decide whether to flush the TLB or not. Signed-off-by: Junaid Shahid <junaids@google.com> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2018-06-12Merge tag 'overflow-v4.18-rc1-part2' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/kees/linux Pull more overflow updates from Kees Cook: "The rest of the overflow changes for v4.18-rc1. This includes the explicit overflow fixes from Silvio, further struct_size() conversions from Matthew, and a bug fix from Dan. But the bulk of it is the treewide conversions to use either the 2-factor argument allocators (e.g. kmalloc(a * b, ...) into kmalloc_array(a, b, ...) or the array_size() macros (e.g. vmalloc(a * b) into vmalloc(array_size(a, b)). Coccinelle was fighting me on several fronts, so I've done a bunch of manual whitespace updates in the patches as well. Summary: - Error path bug fix for overflow tests (Dan) - Additional struct_size() conversions (Matthew, Kees) - Explicitly reported overflow fixes (Silvio, Kees) - Add missing kvcalloc() function (Kees) - Treewide conversions of allocators to use either 2-factor argument variant when available, or array_size() and array3_size() as needed (Kees)" * tag 'overflow-v4.18-rc1-part2' of git://git.kernel.org/pub/scm/linux/kernel/git/kees/linux: (26 commits) treewide: Use array_size in f2fs_kvzalloc() treewide: Use array_size() in f2fs_kzalloc() treewide: Use array_size() in f2fs_kmalloc() treewide: Use array_size() in sock_kmalloc() treewide: Use array_size() in kvzalloc_node() treewide: Use array_size() in vzalloc_node() treewide: Use array_size() in vzalloc() treewide: Use array_size() in vmalloc() treewide: devm_kzalloc() -> devm_kcalloc() treewide: devm_kmalloc() -> devm_kmalloc_array() treewide: kvzalloc() -> kvcalloc() treewide: kvmalloc() -> kvmalloc_array() treewide: kzalloc_node() -> kcalloc_node() treewide: kzalloc() -> kcalloc() treewide: kmalloc() -> kmalloc_array() mm: Introduce kvcalloc() video: uvesafb: Fix integer overflow in allocation UBIFS: Fix potential integer overflow in allocation leds: Use struct_size() in allocation Convert intel uncore to struct_size ...
2018-06-12treewide: kmalloc() -> kmalloc_array()Kees Cook
The kmalloc() function has a 2-factor argument form, kmalloc_array(). This patch replaces cases of: kmalloc(a * b, gfp) with: kmalloc_array(a * b, gfp) as well as handling cases of: kmalloc(a * b * c, gfp) with: kmalloc(array3_size(a, b, c), gfp) as it's slightly less ugly than: kmalloc_array(array_size(a, b), c, gfp) This does, however, attempt to ignore constant size factors like: kmalloc(4 * 1024, gfp) though any constants defined via macros get caught up in the conversion. Any factors with a sizeof() of "unsigned char", "char", and "u8" were dropped, since they're redundant. The tools/ directory was manually excluded, since it has its own implementation of kmalloc(). The Coccinelle script used for this was: // Fix redundant parens around sizeof(). @@ type TYPE; expression THING, E; @@ ( kmalloc( - (sizeof(TYPE)) * E + sizeof(TYPE) * E , ...) | kmalloc( - (sizeof(THING)) * E + sizeof(THING) * E , ...) ) // Drop single-byte sizes and redundant parens. @@ expression COUNT; typedef u8; typedef __u8; @@ ( kmalloc( - sizeof(u8) * (COUNT) + COUNT , ...) | kmalloc( - sizeof(__u8) * (COUNT) + COUNT , ...) | kmalloc( - sizeof(char) * (COUNT) + COUNT , ...) | kmalloc( - sizeof(unsigned char) * (COUNT) + COUNT , ...) | kmalloc( - sizeof(u8) * COUNT + COUNT , ...) | kmalloc( - sizeof(__u8) * COUNT + COUNT , ...) | kmalloc( - sizeof(char) * COUNT + COUNT , ...) | kmalloc( - sizeof(unsigned char) * COUNT + COUNT , ...) ) // 2-factor product with sizeof(type/expression) and identifier or constant. @@ type TYPE; expression THING; identifier COUNT_ID; constant COUNT_CONST; @@ ( - kmalloc + kmalloc_array ( - sizeof(TYPE) * (COUNT_ID) + COUNT_ID, sizeof(TYPE) , ...) | - kmalloc + kmalloc_array ( - sizeof(TYPE) * COUNT_ID + COUNT_ID, sizeof(TYPE) , ...) | - kmalloc + kmalloc_array ( - sizeof(TYPE) * (COUNT_CONST) + COUNT_CONST, sizeof(TYPE) , ...) | - kmalloc + kmalloc_array ( - sizeof(TYPE) * COUNT_CONST + COUNT_CONST, sizeof(TYPE) , ...) | - kmalloc + kmalloc_array ( - sizeof(THING) * (COUNT_ID) + COUNT_ID, sizeof(THING) , ...) | - kmalloc + kmalloc_array ( - sizeof(THING) * COUNT_ID + COUNT_ID, sizeof(THING) , ...) | - kmalloc + kmalloc_array ( - sizeof(THING) * (COUNT_CONST) + COUNT_CONST, sizeof(THING) , ...) | - kmalloc + kmalloc_array ( - sizeof(THING) * COUNT_CONST + COUNT_CONST, sizeof(THING) , ...) ) // 2-factor product, only identifiers. @@ identifier SIZE, COUNT; @@ - kmalloc + kmalloc_array ( - SIZE * COUNT + COUNT, SIZE , ...) // 3-factor product with 1 sizeof(type) or sizeof(expression), with // redundant parens removed. @@ expression THING; identifier STRIDE, COUNT; type TYPE; @@ ( kmalloc( - sizeof(TYPE) * (COUNT) * (STRIDE) + array3_size(COUNT, STRIDE, sizeof(TYPE)) , ...) | kmalloc( - sizeof(TYPE) * (COUNT) * STRIDE + array3_size(COUNT, STRIDE, sizeof(TYPE)) , ...) | kmalloc( - sizeof(TYPE) * COUNT * (STRIDE) + array3_size(COUNT, STRIDE, sizeof(TYPE)) , ...) | kmalloc( - sizeof(TYPE) * COUNT * STRIDE + array3_size(COUNT, STRIDE, sizeof(TYPE)) , ...) | kmalloc( - sizeof(THING) * (COUNT) * (STRIDE) + array3_size(COUNT, STRIDE, sizeof(THING)) , ...) | kmalloc( - sizeof(THING) * (COUNT) * STRIDE + array3_size(COUNT, STRIDE, sizeof(THING)) , ...) | kmalloc( - sizeof(THING) * COUNT * (STRIDE) + array3_size(COUNT, STRIDE, sizeof(THING)) , ...) | kmalloc( - sizeof(THING) * COUNT * STRIDE + array3_size(COUNT, STRIDE, sizeof(THING)) , ...) ) // 3-factor product with 2 sizeof(variable), with redundant parens removed. @@ expression THING1, THING2; identifier COUNT; type TYPE1, TYPE2; @@ ( kmalloc( - sizeof(TYPE1) * sizeof(TYPE2) * COUNT + array3_size(COUNT, sizeof(TYPE1), sizeof(TYPE2)) , ...) | kmalloc( - sizeof(TYPE1) * sizeof(THING2) * (COUNT) + array3_size(COUNT, sizeof(TYPE1), sizeof(TYPE2)) , ...) | kmalloc( - sizeof(THING1) * sizeof(THING2) * COUNT + array3_size(COUNT, sizeof(THING1), sizeof(THING2)) , ...) | kmalloc( - sizeof(THING1) * sizeof(THING2) * (COUNT) + array3_size(COUNT, sizeof(THING1), sizeof(THING2)) , ...) | kmalloc( - sizeof(TYPE1) * sizeof(THING2) * COUNT + array3_size(COUNT, sizeof(TYPE1), sizeof(THING2)) , ...) | kmalloc( - sizeof(TYPE1) * sizeof(THING2) * (COUNT) + array3_size(COUNT, sizeof(TYPE1), sizeof(THING2)) , ...) ) // 3-factor product, only identifiers, with redundant parens removed. @@ identifier STRIDE, SIZE, COUNT; @@ ( kmalloc( - (COUNT) * STRIDE * SIZE + array3_size(COUNT, STRIDE, SIZE) , ...) | kmalloc( - COUNT * (STRIDE) * SIZE + array3_size(COUNT, STRIDE, SIZE) , ...) | kmalloc( - COUNT * STRIDE * (SIZE) + array3_size(COUNT, STRIDE, SIZE) , ...) | kmalloc( - (COUNT) * (STRIDE) * SIZE + array3_size(COUNT, STRIDE, SIZE) , ...) | kmalloc( - COUNT * (STRIDE) * (SIZE) + array3_size(COUNT, STRIDE, SIZE) , ...) | kmalloc( - (COUNT) * STRIDE * (SIZE) + array3_size(COUNT, STRIDE, SIZE) , ...) | kmalloc( - (COUNT) * (STRIDE) * (SIZE) + array3_size(COUNT, STRIDE, SIZE) , ...) | kmalloc( - COUNT * STRIDE * SIZE + array3_size(COUNT, STRIDE, SIZE) , ...) ) // Any remaining multi-factor products, first at least 3-factor products, // when they're not all constants... @@ expression E1, E2, E3; constant C1, C2, C3; @@ ( kmalloc(C1 * C2 * C3, ...) | kmalloc( - (E1) * E2 * E3 + array3_size(E1, E2, E3) , ...) | kmalloc( - (E1) * (E2) * E3 + array3_size(E1, E2, E3) , ...) | kmalloc( - (E1) * (E2) * (E3) + array3_size(E1, E2, E3) , ...) | kmalloc( - E1 * E2 * E3 + array3_size(E1, E2, E3) , ...) ) // And then all remaining 2 factors products when they're not all constants, // keeping sizeof() as the second factor argument. @@ expression THING, E1, E2; type TYPE; constant C1, C2, C3; @@ ( kmalloc(sizeof(THING) * C2, ...) | kmalloc(sizeof(TYPE) * C2, ...) | kmalloc(C1 * C2 * C3, ...) | kmalloc(C1 * C2, ...) | - kmalloc + kmalloc_array ( - sizeof(TYPE) * (E2) + E2, sizeof(TYPE) , ...) | - kmalloc + kmalloc_array ( - sizeof(TYPE) * E2 + E2, sizeof(TYPE) , ...) | - kmalloc + kmalloc_array ( - sizeof(THING) * (E2) + E2, sizeof(THING) , ...) | - kmalloc + kmalloc_array ( - sizeof(THING) * E2 + E2, sizeof(THING) , ...) | - kmalloc + kmalloc_array ( - (E1) * E2 + E1, E2 , ...) | - kmalloc + kmalloc_array ( - (E1) * (E2) + E1, E2 , ...) | - kmalloc + kmalloc_array ( - E1 * E2 + E1, E2 , ...) ) Signed-off-by: Kees Cook <keescook@chromium.org>
2018-06-12Merge tag 'for-linus' of git://git.kernel.org/pub/scm/virt/kvm/kvmLinus Torvalds
Pull KVM updates from Paolo Bonzini: "Small update for KVM: ARM: - lazy context-switching of FPSIMD registers on arm64 - "split" regions for vGIC redistributor s390: - cleanups for nested - clock handling - crypto - storage keys - control register bits x86: - many bugfixes - implement more Hyper-V super powers - implement lapic_timer_advance_ns even when the LAPIC timer is emulated using the processor's VMX preemption timer. - two security-related bugfixes at the top of the branch" * tag 'for-linus' of git://git.kernel.org/pub/scm/virt/kvm/kvm: (79 commits) kvm: fix typo in flag name kvm: x86: use correct privilege level for sgdt/sidt/fxsave/fxrstor access KVM: x86: pass kvm_vcpu to kvm_read_guest_virt and kvm_write_guest_virt_system KVM: x86: introduce linear_{read,write}_system kvm: nVMX: Enforce cpl=0 for VMX instructions kvm: nVMX: Add support for "VMWRITE to any supported field" kvm: nVMX: Restrict VMX capability MSR changes KVM: VMX: Optimize tscdeadline timer latency KVM: docs: nVMX: Remove known limitations as they do not exist now KVM: docs: mmu: KVM support exposing SLAT to guests kvm: no need to check return value of debugfs_create functions kvm: Make VM ioctl do valloc for some archs kvm: Change return type to vm_fault_t KVM: docs: mmu: Fix link to NPT presentation from KVM Forum 2008 kvm: x86: Amend the KVM_GET_SUPPORTED_CPUID API documentation KVM: x86: hyperv: declare KVM_CAP_HYPERV_TLBFLUSH capability KVM: x86: hyperv: simplistic HVCALL_FLUSH_VIRTUAL_ADDRESS_{LIST,SPACE}_EX implementation KVM: x86: hyperv: simplistic HVCALL_FLUSH_VIRTUAL_ADDRESS_{LIST,SPACE} implementation KVM: introduce kvm_make_vcpus_request_mask() API KVM: x86: hyperv: do rep check for each hypercall separately ...
2018-06-06x86/bugs: Add AMD's SPEC_CTRL MSR usageKonrad Rzeszutek Wilk
The AMD document outlining the SSBD handling 124441_AMD64_SpeculativeStoreBypassDisable_Whitepaper_final.pdf mentions that if CPUID 8000_0008.EBX[24] is set we should be using the SPEC_CTRL MSR (0x48) over the VIRT SPEC_CTRL MSR (0xC001_011f) for speculative store bypass disable. This in effect means we should clear the X86_FEATURE_VIRT_SSBD flag so that we would prefer the SPEC_CTRL MSR. See the document titled: 124441_AMD64_SpeculativeStoreBypassDisable_Whitepaper_final.pdf A copy of this document is available at https://bugzilla.kernel.org/show_bug.cgi?id=199889 Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Cc: Tom Lendacky <thomas.lendacky@amd.com> Cc: Janakarajan Natarajan <Janakarajan.Natarajan@amd.com> Cc: kvm@vger.kernel.org Cc: KarimAllah Ahmed <karahmed@amazon.de> Cc: andrew.cooper3@citrix.com Cc: Joerg Roedel <joro@8bytes.org> Cc: Radim Krčmář <rkrcmar@redhat.com> Cc: Andy Lutomirski <luto@kernel.org> Cc: "H. Peter Anvin" <hpa@zytor.com> Cc: Paolo Bonzini <pbonzini@redhat.com> Cc: Borislav Petkov <bp@suse.de> Cc: David Woodhouse <dwmw@amazon.co.uk> Cc: Kees Cook <keescook@chromium.org> Link: https://lkml.kernel.org/r/20180601145921.9500-3-konrad.wilk@oracle.com
2018-06-01kvm: Make VM ioctl do valloc for some archsMarc Orr
The kvm struct has been bloating. For example, it's tens of kilo-bytes for x86, which turns out to be a large amount of memory to allocate contiguously via kzalloc. Thus, this patch does the following: 1. Uses architecture-specific routines to allocate the kvm struct via vzalloc for x86. 2. Switches arm to __KVM_HAVE_ARCH_VM_ALLOC so that it can use vzalloc when has_vhe() is true. Other architectures continue to default to kalloc, as they have a dependency on kalloc or have a small-enough struct kvm. Signed-off-by: Marc Orr <marcorr@google.com> Reviewed-by: Marc Zyngier <marc.zyngier@arm.com> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2018-05-24KVM: x86: prevent integer overflows in KVM_MEMORY_ENCRYPT_REG_REGIONDan Carpenter
This is a fix from reviewing the code, but it looks like it might be able to lead to an Oops. It affects 32bit systems. The KVM_MEMORY_ENCRYPT_REG_REGION ioctl uses a u64 for range->addr and range->size but the high 32 bits would be truncated away on a 32 bit system. This is harmless but it's also harmless to prevent it. Then in sev_pin_memory() the "uaddr + ulen" calculation can wrap around. The wrap around can happen on 32 bit or 64 bit systems, but I was only able to figure out a problem for 32 bit systems. We would pick a number which results in "npages" being zero. The sev_pin_memory() would then return ZERO_SIZE_PTR without allocating anything. I made it illegal to call sev_pin_memory() with "ulen" set to zero. Hopefully, that doesn't cause any problems. I also changed the type of "first" and "last" to long, just for cosmetic reasons. Otherwise on a 64 bit system you're saving "uaddr >> 12" in an int and it truncates the high 20 bits away. The math works in the current code so far as I can see but it's just weird. Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com> [Brijesh noted that the code is only reachable on X86_64.] Reviewed-by: Brijesh Singh <brijesh.singh@amd.com> Signed-off-by: Radim Krčmář <rkrcmar@redhat.com>
2018-05-17KVM: SVM: Implement VIRT_SPEC_CTRL support for SSBDTom Lendacky
Expose the new virtualized architectural mechanism, VIRT_SSBD, for using speculative store bypass disable (SSBD) under SVM. This will allow guests to use SSBD on hardware that uses non-architectural mechanisms for enabling SSBD. [ tglx: Folded the migration fixup from Paolo Bonzini ] Signed-off-by: Tom Lendacky <thomas.lendacky@amd.com> Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2018-05-17x86/bugs, KVM: Extend speculation control for VIRT_SPEC_CTRLThomas Gleixner
AMD is proposing a VIRT_SPEC_CTRL MSR to handle the Speculative Store Bypass Disable via MSR_AMD64_LS_CFG so that guests do not have to care about the bit position of the SSBD bit and thus facilitate migration. Also, the sibling coordination on Family 17H CPUs can only be done on the host. Extend x86_spec_ctrl_set_guest() and x86_spec_ctrl_restore_host() with an extra argument for the VIRT_SPEC_CTRL MSR. Hand in 0 from VMX and in SVM add a new virt_spec_ctrl member to the CPU data structure which is going to be used in later patches for the actual implementation. Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Reviewed-by: Borislav Petkov <bp@suse.de> Reviewed-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
2018-05-17x86/speculation: Use synthetic bits for IBRS/IBPB/STIBPBorislav Petkov
Intel and AMD have different CPUID bits hence for those use synthetic bits which get set on the respective vendor's in init_speculation_control(). So that debacles like what the commit message of c65732e4f721 ("x86/cpu: Restore CPUID_8000_0008_EBX reload") talks about don't happen anymore. Signed-off-by: Borislav Petkov <bp@suse.de> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Reviewed-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com> Tested-by: Jörg Otte <jrg.otte@gmail.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: "Kirill A. Shutemov" <kirill.shutemov@linux.intel.com> Link: https://lkml.kernel.org/r/20180504161815.GG9257@pd.tnic
2018-05-17KVM: SVM: Move spec control call after restore of GSThomas Gleixner
svm_vcpu_run() invokes x86_spec_ctrl_restore_host() after VMEXIT, but before the host GS is restored. x86_spec_ctrl_restore_host() uses 'current' to determine the host SSBD state of the thread. 'current' is GS based, but host GS is not yet restored and the access causes a triple fault. Move the call after the host GS restore. Fixes: 885f82bfbc6f x86/process: Allow runtime control of Speculative Store Bypass Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Reviewed-by: Borislav Petkov <bp@suse.de> Reviewed-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com> Acked-by: Paolo Bonzini <pbonzini@redhat.com>
2018-05-14kvm: vmx: Basic APIC virtualization controls have three settingsJim Mattson
Previously, we toggled between SECONDARY_EXEC_VIRTUALIZE_X2APIC_MODE and SECONDARY_EXEC_VIRTUALIZE_APIC_ACCESSES, depending on whether or not the EXTD bit was set in MSR_IA32_APICBASE. However, if the local APIC is disabled, we should not set either of these APIC virtualization control bits. Signed-off-by: Jim Mattson <jmattson@google.com> Signed-off-by: Krish Sadhukhan <krish.sadhukhan@oracle.com> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2018-05-03x86/speculation: Create spec-ctrl.h to avoid include hellThomas Gleixner
Having everything in nospec-branch.h creates a hell of dependencies when adding the prctl based switching mechanism. Move everything which is not required in nospec-branch.h to spec-ctrl.h and fix up the includes in the relevant files. Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Reviewed-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com> Reviewed-by: Ingo Molnar <mingo@kernel.org>
2018-05-03x86/bugs, KVM: Support the combination of guest and host IBRSKonrad Rzeszutek Wilk
A guest may modify the SPEC_CTRL MSR from the value used by the kernel. Since the kernel doesn't use IBRS, this means a value of zero is what is needed in the host. But the 336996-Speculative-Execution-Side-Channel-Mitigations.pdf refers to the other bits as reserved so the kernel should respect the boot time SPEC_CTRL value and use that. This allows to deal with future extensions to the SPEC_CTRL interface if any at all. Note: This uses wrmsrl() instead of native_wrmsl(). I does not make any difference as paravirt will over-write the callq *0xfff.. with the wrmsrl assembler code. Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Reviewed-by: Borislav Petkov <bp@suse.de> Reviewed-by: Ingo Molnar <mingo@kernel.org>
2018-04-16Merge tag 'for-linus' of git://git.kernel.org/pub/scm/virt/kvm/kvmLinus Torvalds
Pull kvm fixes from Paolo Bonzini: "Bug fixes, plus a new test case and the associated infrastructure for writing nested virtualization tests" * tag 'for-linus' of git://git.kernel.org/pub/scm/virt/kvm/kvm: kvm: selftests: add vmx_tsc_adjust_test kvm: x86: move MSR_IA32_TSC handling to x86.c X86/KVM: Properly update 'tsc_offset' to represent the running guest kvm: selftests: add -std=gnu99 cflags x86: Add check for APIC access address for vmentry of L2 guests KVM: X86: fix incorrect reference of trace_kvm_pi_irte_update X86/KVM: Do not allow DISABLE_EXITS_MWAIT when LAPIC ARAT is not available kvm: selftests: fix spelling mistake: "divisable" and "divisible" X86/VMX: Disable VMX preemption timer if MWAIT is not intercepted
2018-04-16kvm: x86: move MSR_IA32_TSC handling to x86.cPaolo Bonzini
This is not specific to Intel/AMD anymore. The TSC offset is available in vcpu->arch.tsc_offset. Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2018-04-16X86/KVM: Properly update 'tsc_offset' to represent the running guestKarimAllah Ahmed
Update 'tsc_offset' on vmentry/vmexit of L2 guests to ensure that it always captures the TSC_OFFSET of the running guest whether it is the L1 or L2 guest. Cc: Paolo Bonzini <pbonzini@redhat.com> Cc: Radim Krčmář <rkrcmar@redhat.com> Cc: kvm@vger.kernel.org Cc: linux-kernel@vger.kernel.org Reviewed-by: Jim Mattson <jmattson@google.com> Suggested-by: Paolo Bonzini <pbonzini@redhat.com> Signed-off-by: KarimAllah Ahmed <karahmed@amazon.de> [AMD changes, fix update_ia32_tsc_adjust_msr. - Paolo] Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2018-04-11KVM: X86: fix incorrect reference of trace_kvm_pi_irte_updatehu huajun
In arch/x86/kvm/trace.h, this function is declared as host_irq the first input, and vcpu_id the second, instead of otherwise. Signed-off-by: hu huajun <huhuajun@linux.alibaba.com> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2018-04-09Merge tag 'for-linus' of git://git.kernel.org/pub/scm/virt/kvm/kvmLinus Torvalds
Pull kvm updates from Paolo Bonzini: "ARM: - VHE optimizations - EL2 address space randomization - speculative execution mitigations ("variant 3a", aka execution past invalid privilege register access) - bugfixes and cleanups PPC: - improvements for the radix page fault handler for HV KVM on POWER9 s390: - more kvm stat counters - virtio gpu plumbing - documentation - facilities improvements x86: - support for VMware magic I/O port and pseudo-PMCs - AMD pause loop exiting - support for AMD core performance extensions - support for synchronous register access - expose nVMX capabilities to userspace - support for Hyper-V signaling via eventfd - use Enlightened VMCS when running on Hyper-V - allow userspace to disable MWAIT/HLT/PAUSE vmexits - usual roundup of optimizations and nested virtualization bugfixes Generic: - API selftest infrastructure (though the only tests are for x86 as of now)" * tag 'for-linus' of git://git.kernel.org/pub/scm/virt/kvm/kvm: (174 commits) kvm: x86: fix a prototype warning kvm: selftests: add sync_regs_test kvm: selftests: add API testing infrastructure kvm: x86: fix a compile warning KVM: X86: Add Force Emulation Prefix for "emulate the next instruction" KVM: X86: Introduce handle_ud() KVM: vmx: unify adjacent #ifdefs x86: kvm: hide the unused 'cpu' variable KVM: VMX: remove bogus WARN_ON in handle_ept_misconfig Revert "KVM: X86: Fix SMRAM accessing even if VM is shutdown" kvm: Add emulation for movups/movupd KVM: VMX: raise internal error for exception during invalid protected mode state KVM: nVMX: Optimization: Dont set KVM_REQ_EVENT when VMExit with nested_run_pending KVM: nVMX: Require immediate-exit when event reinjected to L2 and L1 event pending KVM: x86: Fix misleading comments on handling pending exceptions KVM: x86: Rename interrupt.pending to interrupt.injected KVM: VMX: No need to clear pending NMI/interrupt on inject realmode interrupt x86/kvm: use Enlightened VMCS when running on Hyper-V x86/hyper-v: detect nested features x86/hyper-v: define struct hv_enlightened_vmcs and clean field bits ...
2018-04-04KVM: X86: Introduce handle_ud()Wanpeng Li
Introduce handle_ud() to handle invalid opcode, this function will be used by later patches. Reviewed-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com> Reviewed-by: Liran Alon <liran.alon@oracle.com> Cc: Paolo Bonzini <pbonzini@redhat.com> Cc: Radim KrÄmář <rkrcmar@redhat.com> Cc: Andrew Cooper <andrew.cooper3@citrix.com> Cc: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com> Cc: Liran Alon <liran.alon@oracle.com> Signed-off-by: Wanpeng Li <wanpengli@tencent.com> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2018-03-28KVM: SVM: Implement pause loop exit logic in SVMBabu Moger
Bring the PLE(pause loop exit) logic to AMD svm driver. While testing, we found this helping in situations where numerous pauses are generated. Without these patches we could see continuos VMEXITS due to pause interceptions. Tested it on AMD EPYC server with boot parameter idle=poll on a VM with 32 vcpus to simulate extensive pause behaviour. Here are VMEXITS in 10 seconds interval. Pauses 810199 504 Total 882184 325415 Signed-off-by: Babu Moger <babu.moger@amd.com> [Prevented the window from dropping below the initial value. - Radim] Signed-off-by: Radim Krčmář <rkrcmar@redhat.com>
2018-03-28KVM: SVM: Add pause filter thresholdBabu Moger
This patch adds the support for pause filtering threshold. This feature support is indicated by CPUID Fn8000_000A_EDX. See AMD APM Vol 2 Section 15.14.4 Pause Intercept Filtering for more details. In this mode, a 16-bit pause filter threshold field is added in VMCB. The threshold value is a cycle count that is used to reset the pause counter. As with simple pause filtering, VMRUN loads the pause count value from VMCB into an internal counter. Then, on each pause instruction the hardware checks the elapsed number of cycles since the most recent pause instruction against the pause Filter Threshold. If the elapsed cycle count is greater than the pause filter threshold, then the internal pause count is reloaded from VMCB and execution continues. If the elapsed cycle count is less than the pause filter threshold, then the internal pause count is decremented. If the count value is less than zero and pause intercept is enabled, a #VMEXIT is triggered. If advanced pause filtering is supported and pause filter threshold field is set to zero, the filter will operate in the simpler, count only mode. Signed-off-by: Babu Moger <babu.moger@amd.com> Signed-off-by: Radim Krčmář <rkrcmar@redhat.com>
2018-03-28KVM: x86: Fix perf timer mode IP reportingAndi Kleen
KVM and perf have a special backdoor mechanism to report the IP for interrupts re-executed after vm exit. This works for the NMIs that perf normally uses. However when perf is in timer mode it doesn't work because the timer interrupt doesn't get this special treatment. This is common when KVM is running nested in another hypervisor which may not implement the PMU, so only timer mode is available. Call the functions to set up the backdoor IP also for non NMI interrupts. I renamed the functions to set up the backdoor IP reporting to be more appropiate for their new use. The SVM change is only compile tested. v2: Moved the functions inline. For the normal interrupt case the before/after functions are now called from x86.c, not arch specific code. For the NMI case we still need to call it in the architecture specific code, because it's already needed in the low level *_run functions. Signed-off-by: Andi Kleen <ak@linux.intel.com> [Removed unnecessary calls from arch handle_external_intr. - Radim] Signed-off-by: Radim Krčmář <rkrcmar@redhat.com>
2018-03-23KVM: SVM: add struct kvm_svm to hold SVM specific KVM varsSean Christopherson
Add struct kvm_svm, which is analagous to struct vcpu_svm, along with a helper to_kvm_svm() to retrieve kvm_svm from a struct kvm *. Move the SVM specific variables and struct definitions out of kvm_arch and into kvm_svm. Cc: Tom Lendacky <thomas.lendacky@amd.com> Cc: Brijesh Singh <brijesh.singh@amd.com> Cc: Suravee Suthikulpanit <suravee.suthikulpanit@amd.com> Signed-off-by: Sean Christopherson <sean.j.christopherson@intel.com> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2018-03-23KVM: x86: move setting of ept_identity_map_addr to vmx.cSean Christopherson
Add kvm_x86_ops->set_identity_map_addr and set ept_identity_map_addr in VMX specific code so that ept_identity_map_addr can be moved out of 'struct kvm_arch' in a future patch. Signed-off-by: Sean Christopherson <sean.j.christopherson@intel.com> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2018-03-23KVM: x86: define SVM/VMX specific kvm_arch_[alloc|free]_vmSean Christopherson
Define kvm_arch_[alloc|free]_vm in x86 as pass through functions to new kvm_x86_ops vm_alloc and vm_free, and move the current allocation logic as-is to SVM and VMX. Vendor specific alloc/free functions set the stage for SVM/VMX wrappers of 'struct kvm', which will allow us to move the growing number of SVM/VMX specific member variables out of 'struct kvm_arch'. Signed-off-by: Sean Christopherson <sean.j.christopherson@intel.com> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2018-03-16KVM: X86: Provide a capability to disable PAUSE interceptsWanpeng Li
Allow to disable pause loop exit/pause filtering on a per VM basis. If some VMs have dedicated host CPUs, they won't be negatively affected due to needlessly intercepted PAUSE instructions. Thanks to Jan H. Schönherr's initial patch. Cc: Paolo Bonzini <pbonzini@redhat.com> Cc: Radim Krčmář <rkrcmar@redhat.com> Cc: Jan H. Schönherr <jschoenh@amazon.de> Signed-off-by: Wanpeng Li <wanpengli@tencent.com> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2018-03-16KVM: X86: Provide a capability to disable HLT interceptsWanpeng Li
If host CPUs are dedicated to a VM, we can avoid VM exits on HLT. This patch adds the per-VM capability to disable them. Cc: Paolo Bonzini <pbonzini@redhat.com> Cc: Radim Krčmář <rkrcmar@redhat.com> Cc: Jan H. Schönherr <jschoenh@amazon.de> Signed-off-by: Wanpeng Li <wanpengli@tencent.com> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2018-03-16KVM: X86: Provide a capability to disable MWAIT interceptsWanpeng Li
Allowing a guest to execute MWAIT without interception enables a guest to put a (physical) CPU into a power saving state, where it takes longer to return from than what may be desired by the host. Don't give a guest that power over a host by default. (Especially, since nothing prevents a guest from using MWAIT even when it is not advertised via CPUID.) Cc: Paolo Bonzini <pbonzini@redhat.com> Cc: Radim Krčmář <rkrcmar@redhat.com> Cc: Jan H. Schönherr <jschoenh@amazon.de> Signed-off-by: Wanpeng Li <wanpengli@tencent.com> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2018-03-16KVM: x86: SVM: Intercept #GP to support access to VMware backdoor portsLiran Alon
If KVM enable_vmware_backdoor module parameter is set, the commit change VMX to now intercept #GP instead of being directly deliviered from CPU to guest. It is done to support access to VMware Backdoor I/O ports even if TSS I/O permission denies it. In that case: 1. A #GP will be raised and intercepted. 2. #GP intercept handler will simulate I/O port access instruction. 3. I/O port access instruction simulation will allow access to VMware backdoor ports specifically even if TSS I/O permission bitmap denies it. Note that the above change introduce slight performance hit as now #GPs are now not deliviered directly from CPU to guest but instead cause #VMExit and instruction emulation. However, this behavior is introduced only when enable_vmware_backdoor KVM module parameter is set. Signed-off-by: Liran Alon <liran.alon@oracle.com> Reviewed-by: Nikita Leshenko <nikita.leshchenko@oracle.com> Reviewed-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com> Reviewed-by: Radim Krčmář <rkrcmar@redhat.com> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2018-03-16KVM: x86: add kvm_fast_pio() to consolidate fast PIO codeSean Christopherson
Add kvm_fast_pio() to consolidate duplicate code in VMX and SVM. Unexport kvm_fast_pio_in() and kvm_fast_pio_out(). Suggested-by: Paolo Bonzini <pbonzini@redhat.com> Signed-off-by: Sean Christopherson <sean.j.christopherson@intel.com> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2018-03-08x86/MSR: Move native_* variants to msr.hBorislav Petkov
... where they belong. No functional change. Signed-off-by: Borislav Petkov <bp@suse.de> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Reviewed-by: Darren Kenny <darren.kenny@oracle.com> Cc: kvm@vger.kernel.org Link: https://lkml.kernel.org/r/20180301151336.12948-1-bp@alien8.de
2018-03-02Merge tag 'for-linus' of git://git.kernel.org/pub/scm/virt/kvm/kvmLinus Torvalds
Pull KVM fixes from Radim Krčmář: "x86: - fix NULL dereference when using userspace lapic - optimize spectre v1 mitigations by allowing guests to use LFENCE - make microcode revision configurable to prevent guests from unnecessarily blacklisting spectre v2 mitigation feature" * tag 'for-linus' of git://git.kernel.org/pub/scm/virt/kvm/kvm: KVM: x86: fix vcpu initialization with userspace lapic KVM: X86: Allow userspace to define the microcode version KVM: X86: Introduce kvm_get_msr_feature() KVM: SVM: Add MSR-based feature support for serializing LFENCE KVM: x86: Add a framework for supporting MSR-based features
2018-03-01KVM: X86: Allow userspace to define the microcode versionWanpeng Li
Linux (among the others) has checks to make sure that certain features aren't enabled on a certain family/model/stepping if the microcode version isn't greater than or equal to a known good version. By exposing the real microcode version, we're preventing buggy guests that don't check that they are running virtualized (i.e., they should trust the hypervisor) from disabling features that are effectively not buggy. Suggested-by: Filippo Sironi <sironi@amazon.de> Cc: Paolo Bonzini <pbonzini@redhat.com> Cc: Radim Krčmář <rkrcmar@redhat.com> Cc: Liran Alon <liran.alon@oracle.com> Cc: Nadav Amit <nadav.amit@gmail.com> Cc: Borislav Petkov <bp@alien8.de> Cc: Tom Lendacky <thomas.lendacky@amd.com> Signed-off-by: Wanpeng Li <wanpengli@tencent.com> Reviewed-by: Paolo Bonzini <pbonzini@redhat.com> Signed-off-by: Radim Krčmář <rkrcmar@redhat.com>
2018-03-01KVM: SVM: Add MSR-based feature support for serializing LFENCETom Lendacky
In order to determine if LFENCE is a serializing instruction on AMD processors, MSR 0xc0011029 (MSR_F10H_DECFG) must be read and the state of bit 1 checked. This patch will add support to allow a guest to properly make this determination. Add the MSR feature callback operation to svm.c and add MSR 0xc0011029 to the list of MSR-based features. If LFENCE is serializing, then the feature is supported, allowing the hypervisor to set the value of the MSR that guest will see. Support is also added to write (hypervisor only) and read the MSR value for the guest. A write by the guest will result in a #GP. A read by the guest will return the value as set by the host. In this way, the support to expose the feature to the guest is controlled by the hypervisor. Reviewed-by: Paolo Bonzini <pbonzini@redhat.com> Signed-off-by: Tom Lendacky <thomas.lendacky@amd.com> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com> Signed-off-by: Radim Krčmář <rkrcmar@redhat.com>