- 01 Nov, 2017 3 commits
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Nicholas Piggin authored
This fixes the message: arch/powerpc/kvm/book3s_segment.S: Assembler messages: arch/powerpc/kvm/book3s_segment.S:330: Warning: invalid register expression Signed-off-by:
Nicholas Piggin <npiggin@gmail.com> Signed-off-by:
Paul Mackerras <paulus@ozlabs.org>
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Greg Kurz authored
Userland passes an array of 64 SLB descriptors to KVM_SET_SREGS, some of which are valid (ie, SLB_ESID_V is set) and the rest are likely all-zeroes (with QEMU at least). Each of them is then passed to kvmppc_mmu_book3s_64_slbmte(), which assumes to find the SLB index in the 3 lower bits of its rb argument. When passed zeroed arguments, it happily overwrites the 0th SLB entry with zeroes. This is exactly what happens while doing live migration with QEMU when the destination pushes the incoming SLB descriptors to KVM PR. When reloading the SLBs at the next synchronization, QEMU first clears its SLB array and only restore valid ones, but the 0th one is now gone and we cannot access the corresponding memory anymore: (qemu) x/x $pc c0000000000b742c: Cannot access memory To avoid this, let's filter out non-valid SLB entries. While here, we also force a full SLB flush before installing new entries. Since SLB is for 64-bit only, we now build this path conditionally to avoid a build break on 32-bit, which doesn't define SLB_ESID_V. Signed-off-by:
Greg Kurz <groug@kaod.org> Reviewed-by:
David Gibson <david@gibson.dropbear.id.au> Signed-off-by:
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Paul Mackerras authored
When running a guest on a POWER9 system with the in-kernel XICS emulation disabled (for example by running QEMU with the parameter "-machine pseries,kernel_irqchip=off"), the kernel does not pass the XICS-related hypercalls such as H_CPPR up to userspace for emulation there as it should. The reason for this is that the real-mode handlers for these hypercalls don't check whether a XICS device has been instantiated before calling the xics-on-xive code. That code doesn't check either, leading to potential NULL pointer dereferences because vcpu->arch.xive_vcpu is NULL. Those dereferences won't cause an exception in real mode but will lead to kernel memory corruption. This fixes it by adding kvmppc_xics_enabled() checks before calling the XICS functions. Cc: stable@vger.kernel.org # v4.11+ Fixes: 5af50993 ("KVM: PPC: Book3S HV: Native usage of the XIVE interrupt controller") Signed-off-by:
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- 15 Oct, 2017 1 commit
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Paul Mackerras authored
This adds code to make sure that we don't try to access the non-existent HPT for a radix guest using the htab file for the VM in debugfs, a file descriptor obtained using the KVM_PPC_GET_HTAB_FD ioctl, or via the KVM_PPC_RESIZE_HPT_{PREPARE,COMMIT} ioctls. At present nothing bad happens if userspace does access these interfaces on a radix guest, mostly because kvmppc_hpt_npte() gives 0 for a radix guest, which in turn is because 1 << -4 comes out as 0 on POWER processors. However, that relies on undefined behaviour, so it is better to be explicit about not accessing the HPT for a radix guest. Signed-off-by:
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- 14 Oct, 2017 5 commits
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Alexey Kardashevskiy authored
The handlers support PR KVM from the day one; however the PR KVM's enable/disable hcalls handler missed these ones. Signed-off-by:
Alexey Kardashevskiy <aik@ozlabs.ru> Signed-off-by:
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Markus Elfring authored
KVM: PPC: Book3S HV: Delete an error message for a failed memory allocation in kvmppc_allocate_hpt() Omit an extra message for a memory allocation failure in this function. This issue was detected by using the Coccinelle software. Signed-off-by:
Markus Elfring <elfring@users.sourceforge.net> Signed-off-by:
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Thomas Meyer authored
Use vma_pages function on vma object instead of explicit computation. Found by coccinelle spatch "api/vma_pages.cocci" Signed-off-by:
Thomas Meyer <thomas@m3y3r.de> Signed-off-by:
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Thomas Meyer authored
Use ARRAY_SIZE macro, rather than explicitly coding some variant of it yourself. Found with: find -type f -name "*.c" -o -name "*.h" | xargs perl -p -i -e 's/\bsizeof\s*\(\s*(\w+)\s*\)\s*\ /\s*sizeof\s*\(\s*\1\s*\[\s*0\s*\]\s*\) /ARRAY_SIZE(\1)/g' and manual check/verification. Signed-off-by:
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Paul Mackerras authored
At present, if an interrupt (i.e. an exception or trap) occurs in the code where KVM is switching the MMU to or from guest context, we jump to kvmppc_bad_host_intr, where we simply spin with interrupts disabled. In this situation, it is hard to debug what happened because we get no indication as to which interrupt occurred or where. Typically we get a cascade of stall and soft lockup warnings from other CPUs. In order to get more information for debugging, this adds code to create a stack frame on the emergency stack and save register values to it. We start half-way down the emergency stack in order to give ourselves some chance of being able to do a stack trace on secondary threads that are already on the emergency stack. On POWER7 or POWER8, we then just spin, as before, because we don't know what state the MMU context is in or what other threads are doing, and we can't switch back to host context without coordinating with other threads. On POWER9 we can do better; there we load up the host MMU context and jump to C code, which prints an oops message to the console and panics. Signed-off-by:
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- 12 Oct, 2017 31 commits
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Paolo Bonzini authored
The x86 MMU if full of code that returns 0 and 1 for retry/emulate. Use the existing RET_MMIO_PF_RETRY/RET_MMIO_PF_EMULATE enum, renaming it to drop the MMIO part. Signed-off-by:Paolo Bonzini <pbonzini@redhat.com>
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Ladi Prosek authored
Entering SMM while running in guest mode wasn't working very well because several pieces of the vcpu state were left set up for nested operation. Some of the issues observed: * L1 was getting unexpected VM exits (using L1 interception controls but running in SMM execution environment) * MMU was confused (walk_mmu was still set to nested_mmu) * INTERCEPT_SMI was not emulated for L1 (KVM never injected SVM_EXIT_SMI) Intel SDM actually prescribes the logical processor to "leave VMX operation" upon entering SMM in 34.14.1 Default Treatment of SMI Delivery. AMD doesn't seem to document this but they provide fields in the SMM state-save area to stash the current state of SVM. What we need to do is basically get out of guest mode for the duration of SMM. All this completely transparent to L1, i.e. L1 is not given control and no L1 observable state changes. To avoid code duplication this commit takes advantage of the existing nested vmexit and run functionality, perhaps at the cost of efficiency. To get out of guest mode, nested_svm_vmexit is called, unchanged. Re-entering is performed using enter_svm_guest_mode. This commit fixes running Windows Server 2016 with Hyper-V enabled in a VM with OVMF firmware (OVMF_CODE-need-smm.fd). Signed-off-by:
Ladi Prosek <lprosek@redhat.com> Signed-off-by:
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Ladi Prosek authored
Analogous to 858e25c0 ("kvm: nVMX: Refactor nested_vmx_run()"), this commit splits nested_svm_vmrun into two parts. The newly introduced enter_svm_guest_mode modifies the vcpu state to transition from L1 to L2, while the code left in nested_svm_vmrun handles the VMRUN instruction. Signed-off-by:
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Ladi Prosek authored
Entering SMM while running in guest mode wasn't working very well because several pieces of the vcpu state were left set up for nested operation. Some of the issues observed: * L1 was getting unexpected VM exits (using L1 interception controls but running in SMM execution environment) * SMM handler couldn't write to vmx_set_cr4 because of incorrect validity checks predicated on nested.vmxon * MMU was confused (walk_mmu was still set to nested_mmu) Intel SDM actually prescribes the logical processor to "leave VMX operation" upon entering SMM in 34.14.1 Default Treatment of SMI Delivery. What we need to do is basically get out of guest mode and set nested.vmxon to false for the duration of SMM. All this completely transparent to L1, i.e. L1 is not given control and no L1 observable state changes. To avoid code duplication this commit takes advantage of the existing nested vmexit and run functionality, perhaps at the cost of efficiency. To get out of guest mode, nested_vmx_vmexit with exit_reason == -1 is called, a trick already used in vmx_leave_nested. Re-entering is cleaner, using enter_vmx_non_root_mode. This commit fixes running Windows Server 2016 with Hyper-V enabled in a VM with OVMF firmware (OVMF_CODE-need-smm.fd). Signed-off-by:
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Ladi Prosek authored
Intel SDM 27.5.2 Loading Host Segment and Descriptor-Table Registers: "The GDTR and IDTR limits are each set to FFFFH." Signed-off-by:
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Ladi Prosek authored
Similar to NMI, there may be ISA specific reasons why an SMI cannot be injected into the guest. This commit adds a new smi_allowed callback to be implemented in following commits. Signed-off-by:
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Ladi Prosek authored
Entering and exiting SMM may require ISA specific handling under certain circumstances. This commit adds two new callbacks with empty implementations. Actual functionality will be added in following commits. * pre_enter_smm() is to be called when injecting an SMM, before any SMM related vcpu state has been changed * pre_leave_smm() is to be called when emulating the RSM instruction, when the vcpu is in real mode and before any SMM related vcpu state has been restored Signed-off-by:
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Paolo Bonzini authored
It has always annoyed me a bit how SVM_EXIT_NPF is handled by pf_interception. This is also the only reason behind the under-documented need_unprotect argument to kvm_handle_page_fault. Let NPF go straight to kvm_mmu_page_fault, just like VMX does in handle_ept_violation and handle_ept_misconfig. Reviewed-by:
Brijesh Singh <brijesh.singh@amd.com> Signed-off-by:
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Paolo Bonzini authored
Checking the mode is unnecessary, and is done without a memory barrier separating the LAPIC write from the vcpu->mode read; in addition, kvm_vcpu_wake_up is already doing a check for waiters on the wait queue that has the same effect. In practice it's safe because spin_lock has full-barrier semantics on x86, but don't be too clever. Reviewed-by:
Radim Krčmář <rkrcmar@redhat.com> Signed-off-by:
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Tim Hansen authored
Remove redundant null checks before calling kmem_cache_destroy. Found with make coccicheck M=arch/x86/kvm on linux-next tag next-20170929. Signed-off-by:
Tim Hansen <devtimhansen@gmail.com> Signed-off-by:
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Wanpeng Li authored
SDM mentioned: "If either the “unrestricted guest†VM-execution control or the “mode-based execute control for EPT†VM- execution control is 1, the “enable EPT†VM-execution control must also be 1." However, we can still observe unrestricted_guest is Y after inserting the kvm-intel.ko w/ ept=N. It depends on later starts a guest in order that the function vmx_compute_secondary_exec_control() can be executed, then both the module parameter and exec control fields will be amended. This patch fixes it by amending module parameter immediately during vmcs data setup. Reviewed-by:
Jim Mattson <jmattson@google.com> Cc: Paolo Bonzini <pbonzini@redhat.com> Cc: Radim Krčmář <rkrcmar@redhat.com> Cc: Jim Mattson <jmattson@google.com> Signed-off-by:
Wanpeng Li <wanpeng.li@hotmail.com> Signed-off-by:
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Wanpeng Li authored
- XCR0 is reset to 1 by RESET but not INIT - XSS is zeroed by both RESET and INIT - BNDCFGU, BND0-BND3, BNDCFGS, BNDSTATUS are zeroed by both RESET and INIT This patch does this according to SDM. Cc: Paolo Bonzini <pbonzini@redhat.com> Cc: Radim Krčmář <rkrcmar@redhat.com> Cc: Jim Mattson <jmattson@google.com> Signed-off-by:
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Radim Krčmář authored
Our routines look at tscdeadline and period when deciding state of a timer. The timer is disarmed when switching between TSC deadline and other modes, so we should set everything to disarmed state. Signed-off-by:
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Radim Krčmář authored
preemption timer only looks at tscdeadline and could inject already disarmed timer. Signed-off-by:
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Radim Krčmář authored
0 should disable the timer, but start_hv_timer will recognize it as an expired timer instead. Signed-off-by:
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Shakeel Butt authored
The kvm slabs can consume a significant amount of system memory and indeed in our production environment we have observed that a lot of machines are spending significant amount of memory that can not be left as system memory overhead. Also the allocations from these slabs can be triggered directly by user space applications which has access to kvm and thus a buggy application can leak such memory. So, these caches should be accounted to kmemcg. Signed-off-by:
Shakeel Butt <shakeelb@google.com> Signed-off-by:
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David Hildenbrand authored
Let's just name these according to the SDM. This should make it clearer that the are used to enable exiting and not the feature itself. Signed-off-by:
David Hildenbrand <david@redhat.com> Signed-off-by:
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David Hildenbrand authored
Changing it afterwards doesn't make too much sense and will only result in inconsistencies. Reviewed-by:
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David Hildenbrand authored
Setting it to 0 leads to setting it to the default value, let's document this. Reviewed-by:
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David Hildenbrand authored
No need for another enable_ept check. kvm->arch.ept_identity_map_addr only has to be inititalized once. Having alloc_identity_pagetable() is overkill and dropping BUG_ONs is always nice. Reviewed-by:
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David Hildenbrand authored
They are inititally 0, so no need to reset them to 0. Signed-off-by:
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David Hildenbrand authored
vcpu->cpu is not cleared when doing a vmx_vcpu_put/load, so this can be dropped. Reviewed-by:
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David Hildenbrand authored
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David Hildenbrand authored
Without this, we won't be able to do any flushes, so let's just require it. Should be absent in very strange configurations. Suggested-by:
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David Hildenbrand authored
ept_* function should only be called with enable_ept being set. Reviewed-by:
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David Hildenbrand authored
This function is only called with enable_ept. Reviewed-by:
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David Hildenbrand authored
vmx and svm use zalloc, so this is not necessary. Reviewed-by:
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David Hildenbrand authored
Make it a void and drop error handling code. Reviewed-by:
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David Hildenbrand authored
And also get rid of that superfluous local variable "kvm". Reviewed-by:
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David Hildenbrand authored
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David Hildenbrand authored
Let's just drop the return. Reviewed-by:
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