- 18 Nov, 2021 4 commits
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Maxim Levitsky authored
Incorporate EFER.LMA into kvm_mmu_extended_role, as it used to compute the guest root level and is not reflected in kvm_mmu_page_role.level when TDP is in use. When simply running the guest, it is impossible for EFER.LMA and kvm_mmu.root_level to get out of sync, as the guest cannot transition from PAE paging to 64-bit paging without toggling CR0.PG, i.e. without first bouncing through a different MMU context. And stuffing guest state via KVM_SET_SREGS{,2} also ensures a full MMU context reset. However, if KVM_SET_SREGS{,2} is followed by KVM_SET_NESTED_STATE, e.g. to set guest state when migrating the VM while L2 is active, the vCPU state will reflect L2, not L1. If L1 is using TDP for L2, then root_mmu will have been configured using L2's state, despite not being used for L2. If L2.EFER.LMA != L1.EFER.LMA, and L2 is using PAE paging, then root_mmu will be configured for guest PAE paging, but will match the mmu_role for 64-bit paging and cause KVM to not reconfigure root_mmu on the next nested VM-Exit. Alternatively, the root_mmu's role could be invalidated after a successful KVM_SET_NESTED_STATE that yields vcpu->arch.mmu != vcpu->arch.root_mmu, i.e. that switches the active mmu to guest_mmu, but doing so is unnecessarily tricky, and not even needed if L1 and L2 do have the same role (e.g., they are both 64-bit guests and run with the same CR4). Suggested-by:Sean Christopherson <seanjc@google.com> Signed-off-by:
Maxim Levitsky <mlevitsk@redhat.com> Message-Id: <20211115131837.195527-3-mlevitsk@redhat.com> Cc: stable@vger.kernel.org Signed-off-by:
Paolo Bonzini <pbonzini@redhat.com>
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Maxim Levitsky authored
When loading nested state, don't use check vcpu->arch.efer to get the L1 host's 64-bit vs. 32-bit state and don't check it for consistency with respect to VM_EXIT_HOST_ADDR_SPACE_SIZE, as register state in vCPU may be stale when KVM_SET_NESTED_STATE is called---and architecturally does not exist. When restoring L2 state in KVM, the CPU is placed in non-root where nested VMX code has no snapshot of L1 host state: VMX (conditionally) loads host state fields loaded on VM-exit, but they need not correspond to the state before entry. A simple case occurs in KVM itself, where the host RIP field points to vmx_vmexit rather than the instruction following vmlaunch/vmresume. However, for the particular case of L1 being in 32- or 64-bit mode on entry, the exit controls can be treated instead as the source of truth regarding the state of L1 on entry, and can be used to check that vmcs12.VM_EXIT_HOST_ADDR_SPACE_SIZE matches vmcs12.HOST_EFER if vmcs12.VM_EXIT_LOAD_IA32_EFER is set. The consistency check on CPU EFER vs. vmcs12.VM_EXIT_HOST_ADDR_SPACE_SIZE, instead, happens only on VM-Enter. That's because, again, there's conceptually no "current" L1 EFER to check on KVM_SET_NESTED_STATE. Suggested-by:
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David Woodhouse authored
In 64-bit mode, x86 instruction encoding allows us to use the low 8 bits of any GPR as an 8-bit operand. In 32-bit mode, however, we can only use the [abcd] registers. For which, GCC has the "q" constraint instead of the less restrictive "r". Also fix st->preempted, which is an input/output operand rather than an input. Fixes: 7e2175eb ("KVM: x86: Fix recording of guest steal time / preempted status") Reported-by:
kernel test robot <lkp@intel.com> Signed-off-by:
David Woodhouse <dwmw@amazon.co.uk> Message-Id: <89bf72db1b859990355f9c40713a34e0d2d86c98.camel@infradead.org> Signed-off-by:
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Paul Durrant authored
The lack a static declaration currently results in: arch/x86/kvm/cpuid.c:128:26: warning: no previous prototype for function 'kvm_find_kvm_cpuid_features' when compiling with "W=1". Reported-by:
Paul Durrant <pdurrant@amazon.com> Message-Id: <20211115144131.5943-1-pdurrant@amazon.com> Signed-off-by:
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- 16 Nov, 2021 1 commit
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黄乐 authored
In vcpu_load_eoi_exitmap(), currently the eoi_exit_bitmap[4] array is initialized only when Hyper-V context is available, in other path it is just passed to kvm_x86_ops.load_eoi_exitmap() directly from on the stack, which would cause unexpected interrupt delivery/handling issues, e.g. an *old* linux kernel that relies on PIT to do clock calibration on KVM might randomly fail to boot. Fix it by passing ioapic_handled_vectors to load_eoi_exitmap() when Hyper-V context is not available. Fixes: f2bc14b6 ("KVM: x86: hyper-v: Prepare to meet unallocated Hyper-V context") Cc: stable@vger.kernel.org Reviewed-by:
Vitaly Kuznetsov <vkuznets@redhat.com> Signed-off-by:
Huang Le <huangle1@jd.com> Message-Id: <62115b277dab49ea97da5633f8522daf@jd.com> Signed-off-by:
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- 11 Nov, 2021 16 commits
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Vitaly Kuznetsov authored
KVM_CAP_NR_VCPUS is used to get the "recommended" maximum number of VCPUs and arm64/mips/riscv report num_online_cpus(). Powerpc reports either num_online_cpus() or num_present_cpus(), s390 has multiple constants depending on hardware features. On x86, KVM reports an arbitrary value of '710' which is supposed to be the maximum tested value but it's possible to test all KVM_MAX_VCPUS even when there are less physical CPUs available. Drop the arbitrary '710' value and return num_online_cpus() on x86 as well. The recommendation will match other architectures and will mean 'no CPU overcommit'. For reference, QEMU only queries KVM_CAP_NR_VCPUS to print a warning when the requested vCPU number exceeds it. The static limit of '710' is quite weird as smaller systems with just a few physical CPUs should certainly "recommend" less. Suggested-by:
Eduardo Habkost <ehabkost@redhat.com> Signed-off-by:
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Vipin Sharma authored
Handle #GP on INVPCID due to an invalid type in the common switch statement instead of relying on the callers (VMX and SVM) to manually validate the type. Unlike INVVPID and INVEPT, INVPCID is not explicitly documented to check the type before reading the operand from memory, so deferring the type validity check until after that point is architecturally allowed. Signed-off-by:
Vipin Sharma <vipinsh@google.com> Reviewed-by:
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Vipin Sharma authored
handle_invept(), handle_invvpid(), handle_invpcid() read the same reg2 field in vmcs.VMX_INSTRUCTION_INFO to get the index of the GPR that holds the invalidation type. Add a helper to retrieve reg2 from VMX instruction info to consolidate and document the shift+mask magic. Signed-off-by:
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Sean Christopherson authored
Clean up the x2APIC MSR bitmap intereption code for L2, which is the last holdout of open coded bitmap manipulations. Freshen up the SDM/PRM comment, rename the function to make it abundantly clear the funky behavior is x2APIC specific, and explain _why_ vmcs01's bitmap is ignored (the previous comment was flat out wrong for x2APIC behavior). No functional change intended. Signed-off-by:
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Sean Christopherson authored
Add builder macros to generate the MSR bitmap helpers to reduce the amount of copy-paste code, especially with respect to all the magic numbers needed to calc the correct bit location. No functional change intended. Signed-off-by:
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Sean Christopherson authored
Always check vmcs01's MSR bitmap when merging L0 and L1 bitmaps for L2, and always update the relevant bits in vmcs02. This fixes two distinct, but intertwined bugs related to dynamic MSR bitmap modifications. The first issue is that KVM fails to enable MSR interception in vmcs02 for the FS/GS base MSRs if L1 first runs L2 with interception disabled, and later enables interception. The second issue is that KVM fails to honor userspace MSR filtering when preparing vmcs02. Fix both issues simultaneous as fixing only one of the issues (doesn't matter which) would create a mess that no one should have to bisect. Fixing only the first bug would exacerbate the MSR filtering issue as userspace would see inconsistent behavior depending on the whims of L1. Fixing only the second bug (MSR filtering) effectively requires fixing the first, as the nVMX code only knows how to transition vmcs02's bitmap from 1->0. Move the various accessor/mutators that are currently buried in vmx.c into vmx.h so that they can be shared by the nested code. Fixes: 1a155254 ("KVM: x86: Introduce MSR filtering") Fixes: d69129b4 ("KVM: nVMX: Disable intercept for FS/GS base MSRs in vmcs02 when possible") Cc: stable@vger.kernel.org Cc: Alexander Graf <graf@amazon.com> Signed-off-by:
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Sean Christopherson authored
Check the current VMCS controls to determine if an MSR write will be intercepted due to MSR bitmaps being disabled. In the nested VMX case, KVM will disable MSR bitmaps in vmcs02 if they're disabled in vmcs12 or if KVM can't map L1's bitmaps for whatever reason. Note, the bad behavior is relatively benign in the current code base as KVM sets all bits in vmcs02's MSR bitmap by default, clears bits if and only if L0 KVM also disables interception of an MSR, and only uses the buggy helper for MSR_IA32_SPEC_CTRL. Because KVM explicitly tests WRMSR before disabling interception of MSR_IA32_SPEC_CTRL, the flawed check will only result in KVM reading MSR_IA32_SPEC_CTRL from hardware when it isn't strictly necessary. Tag the fix for stable in case a future fix wants to use msr_write_intercepted(), in which case a buggy implementation in older kernels could prove subtly problematic. Fixes: d28b387f ("KVM/VMX: Allow direct access to MSR_IA32_SPEC_CTRL") Cc: stable@vger.kernel.org Signed-off-by:
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Vitaly Kuznetsov authored
KVM: x86: Don't update vcpu->arch.pv_eoi.msr_val when a bogus value was written to MSR_KVM_PV_EOI_EN When kvm_gfn_to_hva_cache_init() call from kvm_lapic_set_pv_eoi() fails, MSR write to MSR_KVM_PV_EOI_EN results in #GP so it is reasonable to expect that the value we keep internally in KVM wasn't updated. Signed-off-by:
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Vitaly Kuznetsov authored
kvm_lapic_enable_pv_eoi() is a misnomer as the function is also used to disable PV EOI. Rename it to kvm_lapic_set_pv_eoi(). No functional change intended. Signed-off-by:
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Paul Durrant authored
Currently when kvm_update_cpuid_runtime() runs, it assumes that the KVM_CPUID_FEATURES leaf is located at 0x40000001. This is not true, however, if Hyper-V support is enabled. In this case the KVM leaves will be offset. This patch introdues as new 'kvm_cpuid_base' field into struct kvm_vcpu_arch to track the location of the KVM leaves and function kvm_update_kvm_cpuid_base() (called from kvm_set_cpuid()) to locate the leaves using the 'KVMKVMKVM\0\0\0' signature (which is now given a definition in kvm_para.h). Adjustment of KVM_CPUID_FEATURES will hence now target the correct leaf. NOTE: A new for_each_possible_hypervisor_cpuid_base() macro is intoduced into processor.h to avoid having duplicate code for the iteration over possible hypervisor base leaves. Signed-off-by: -
Sean Christopherson authored
Move the core logic of SET_CPUID and SET_CPUID2 to a common helper, the only difference between the two ioctls() is the format of the userspace struct. A future fix will add yet more code to the core logic. No functional change intended. Cc: stable@vger.kernel.org Signed-off-by:
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Junaid Shahid authored
The fast page fault path bails out on write faults to huge pages in order to accommodate dirty logging. This change adds a check to do that only when dirty logging is actually enabled, so that access tracking for huge pages can still use the fast path for write faults in the common case. Signed-off-by:
Junaid Shahid <junaids@google.com> Reviewed-by:
Ben Gardon <bgardon@google.com> Reviewed-by:
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Sean Christopherson authored
Wrap the read of iter->sptep in tdp_mmu_map_handle_target_level() with rcu_dereference(). Shadow pages in the TDP MMU, and thus their SPTEs, are protected by rcu. This fixes a Sparse warning at tdp_mmu.c:900:51: warning: incorrect type in argument 1 (different address spaces) expected unsigned long long [usertype] *sptep got unsigned long long [noderef] [usertype] __rcu *[usertype] sptep Fixes: 7158bee4 ("KVM: MMU: pass kvm_mmu_page struct to make_spte") Cc: Ben Gardon <bgardon@google.com> Signed-off-by:
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Maxim Levitsky authored
KVM_GUESTDBG_BLOCKIRQ relies on interrupts being injected using standard kvm's inject_pending_event, and not via APICv/AVIC. Since this is a debug feature, just inhibit APICv/AVIC while KVM_GUESTDBG_BLOCKIRQ is in use on at least one vCPU. Fixes: 61e5f69e ("KVM: x86: implement KVM_GUESTDBG_BLOCKIRQ") Reported-by:
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Jim Mattson authored
These function names sound like predicates, and they have siblings, *is_valid_msr(), which _are_ predicates. Moreover, there are comments that essentially warn that these functions behave unexpectedly. Flip the polarity of the return values, so that they become predicates, and convert the boolean result to a success/failure code at the outer call site. Suggested-by:
Jim Mattson <jmattson@google.com> Reviewed-by:
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David Woodhouse authored
In commit b0431382 ("x86/KVM: Make sure KVM_VCPU_FLUSH_TLB flag is not missed") we switched to using a gfn_to_pfn_cache for accessing the guest steal time structure in order to allow for an atomic xchg of the preempted field. This has a couple of problems. Firstly, kvm_map_gfn() doesn't work at all for IOMEM pages when the atomic flag is set, which it is in kvm_steal_time_set_preempted(). So a guest vCPU using an IOMEM page for its steal time would never have its preempted field set. Secondly, the gfn_to_pfn_cache is not invalidated in all cases where it should have been. There are two stages to the GFN->PFN conversion; first the GFN is converted to a userspace HVA, and then that HVA is looked up in the process page tables to find the underlying host PFN. Correct invalidation of the latter would require being hooked up to the MMU notifiers, but that doesn't happen---so it just keeps mapping and unmapping the *wrong* PFN after the userspace page tables change. In the !IOMEM case at least the stale page *is* pinned all the time it's cached, so it won't be freed and reused by anyone else while still receiving the steal time updates. The map/unmap dance only takes care of the KVM administrivia such as marking the page dirty. Until the gfn_to_pfn cache handles the remapping automatically by integrating with the MMU notifiers, we might as well not get a kernel mapping of it, and use the perfectly serviceable userspace HVA that we already have. We just need to implement the atomic xchg on the userspace address with appropriate exception handling, which is fairly trivial. Cc: stable@vger.kernel.org Fixes: b0431382 ("x86/KVM: Make sure KVM_VCPU_FLUSH_TLB flag is not missed") Signed-off-by:
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- 02 Nov, 2021 1 commit
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https://github.com/kvm-riscv/linuxPaolo Bonzini authored
Minor cocci warning fixes: 1) Bool return warning fix 2) Unnedded semicolon warning fix
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- 01 Nov, 2021 2 commits
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Bixuan Cui authored
Fix boolreturn.cocci warnings: ./arch/riscv/kvm/mmu.c:603:9-10: WARNING: return of 0/1 in function 'kvm_age_gfn' with return type bool ./arch/riscv/kvm/mmu.c:582:9-10: WARNING: return of 0/1 in function 'kvm_set_spte_gfn' with return type bool ./arch/riscv/kvm/mmu.c:621:9-10: WARNING: return of 0/1 in function 'kvm_test_age_gfn' with return type bool ./arch/riscv/kvm/mmu.c:568:9-10: WARNING: return of 0/1 in function 'kvm_unmap_gfn_range' with return type bool Signed-off-by:
Bixuan Cui <cuibixuan@linux.alibaba.com> Signed-off-by:
Anup Patel <anup.patel@wdc.com>
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ran jianping authored
Elimate the following coccinelle check warning: ./arch/riscv/kvm/vcpu_sbi.c:169:2-3: Unneeded semicolon ./arch/riscv/kvm/vcpu_exit.c:397:2-3: Unneeded semicolon ./arch/riscv/kvm/vcpu_exit.c:687:2-3: Unneeded semicolon ./arch/riscv/kvm/vcpu_exit.c:645:2-3: Unneeded semicolon ./arch/riscv/kvm/vcpu.c:247:2-3: Unneeded semicolon ./arch/riscv/kvm/vcpu.c:284:2-3: Unneeded semicolon ./arch/riscv/kvm/vcpu_timer.c:123:2-3: Unneeded semicolon ./arch/riscv/kvm/vcpu_timer.c:170:2-3: Unneeded semicolon Reported-by:
Zeal Robot <zealci@zte.com.cn> Signed-off-by:
ran jianping <ran.jianping@zte.com.cn> Signed-off-by:
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- 31 Oct, 2021 4 commits
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Paolo Bonzini authored
Merge tag 'kvm-s390-next-5.16-1' of git://git.kernel.org/pub/scm/linux/kernel/git/kvms390/linux into HEAD KVM: s390: Fixes and Features for 5.16 - SIGP Fixes - initial preparations for lazy destroy of secure VMs - storage key improvements/fixes - Log the guest CPNC
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Anup Patel authored
The parameter passed to HFENCE.GVMA instruction in rs1 register is guest physical address right shifted by 2 (i.e. divided by 4). Unfortunately, we overlooked the semantics of rs1 registers for HFENCE.GVMA instruction and never right shifted guest physical address by 2. This issue did not manifest for hypervisors till now because: 1) Currently, only __kvm_riscv_hfence_gvma_all() and SBI HFENCE calls are used to invalidate TLB. 2) All H-extension implementations (such as QEMU, Spike, Rocket Core FPGA, etc) that we tried till now were conservatively flushing everything upon any HFENCE.GVMA instruction. This patch fixes GPA passed to __kvm_riscv_hfence_gvma_vmid_gpa() and __kvm_riscv_hfence_gvma_gpa() functions. Fixes: fd7bb4a2 ("RISC-V: KVM: Implement VMID allocator") Reported-by:Ian Huang <ihuang@ventanamicro.com> Signed-off-by:
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Anup Patel authored
The timer and SBI virtualization is already in separate sources. In future, we will have vector and AIA virtualization also added as separate sources. To align with above described modularity, we factor-out FP virtualization into separate sources. Signed-off-by:
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git://git.kernel.org/pub/scm/linux/kernel/git/kvmarm/kvmarmPaolo Bonzini authored
KVM/arm64 updates for Linux 5.16 - More progress on the protected VM front, now with the full fixed feature set as well as the limitation of some hypercalls after initialisation. - Cleanup of the RAZ/WI sysreg handling, which was pointlessly complicated - Fixes for the vgic placement in the IPA space, together with a bunch of selftests - More memcg accounting of the memory allocated on behalf of a guest - Timer and vgic selftests - Workarounds for the Apple M1 broken vgic implementation - KConfig cleanups - New kvmarm.mode=none option, for those who really dislike us
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- 27 Oct, 2021 3 commits
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Collin Walling authored
The diag 318 data contains values that denote information regarding the guest's environment. Currently, it is unecessarily difficult to observe this value (either manually-inserted debug statements, gdb stepping, mem dumping etc). It's useful to observe this information to obtain an at-a-glance view of the guest's environment, so lets add a simple VCPU event that prints the CPNC to the s390dbf logs. Signed-off-by:
Collin Walling <walling@linux.ibm.com> Acked-by:
Christian Borntraeger <borntraeger@de.ibm.com> Link: https://lore.kernel.org/r/20211027025451.290124-1-walling@linux.ibm.com [borntraeger@de.ibm.com]: change debug level to 3 Signed-off-by:
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Claudio Imbrenda authored
Introduce variants of the convert and destroy page functions that also clear the PG_arch_1 bit used to mark them as secure pages. The PG_arch_1 flag is always allowed to overindicate; using the new functions introduced here allows to reduce the extent of overindication and thus improve performance. These new functions can only be called on pages for which a reference is already being held. Signed-off-by:
Claudio Imbrenda <imbrenda@linux.ibm.com> Reviewed-by:
Janosch Frank <frankja@linux.ibm.com> Reviewed-by:
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Janis Schoetterl-Glausch authored
If handle_sske cannot set the storage key, because there is no page table entry or no present large page entry, it calls fixup_user_fault. However, currently, if the call succeeds, handle_sske returns -EAGAIN, without having set the storage key. Instead, retry by continue'ing the loop without incrementing the address. The same issue in handle_pfmf was fixed by a11bdb1a ("KVM: s390: Fix pfmf and conditional skey emulation"). Fixes: bd096f64 ("KVM: s390: Add skey emulation fault handling") Signed-off-by:
Janis Schoetterl-Glausch <scgl@linux.ibm.com> Reviewed-by:
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- 25 Oct, 2021 9 commits
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Paolo Bonzini authored
pvclock_gtod_sync_lock is completely gone in Linux 5.16. Include this fix into the kvm/next history to record that the syzkaller report is not valid there. Signed-off-by: -
David Woodhouse authored
On the preemption path when updating a Xen guest's runstate times, this lock is taken inside the scheduler rq->lock, which is a raw spinlock. This was shown in a lockdep warning: [ 89.138354] ============================= [ 89.138356] [ BUG: Invalid wait context ] [ 89.138358] 5.15.0-rc5+ #834 Tainted: G S I E [ 89.138360] ----------------------------- [ 89.138361] xen_shinfo_test/2575 is trying to lock: [ 89.138363] ffffa34a0364efd8 (&kvm->arch.pvclock_gtod_sync_lock){....}-{3:3}, at: get_kvmclock_ns+0x1f/0x130 [kvm] [ 89.138442] other info that might help us debug this: [ 89.138444] context-{5:5} [ 89.138445] 4 locks held by xen_shinfo_test/2575: [ 89.138447] #0: ffff972bdc3b8108 (&vcpu->mutex){+.+.}-{4:4}, at: kvm_vcpu_ioctl+0x77/0x6f0 [kvm] [ 89.138483] #1: ffffa34a03662e90 (&kvm->srcu){....}-{0:0}, at: kvm_arch_vcpu_ioctl_run+0xdc/0x8b0 [kvm] [ 89.138526] #2: ffff97331fdbac98 (&rq->__lock){-.-.}-{2:2}, at: __schedule+0xff/0xbd0 [ 89.138534] #3: ffffa34a03662e90 (&kvm->srcu){....}-{0:0}, at: kvm_arch_vcpu_put+0x26/0x170 [kvm] ... [ 89.138695] get_kvmclock_ns+0x1f/0x130 [kvm] [ 89.138734] kvm_xen_update_runstate+0x14/0x90 [kvm] [ 89.138783] kvm_xen_update_runstate_guest+0x15/0xd0 [kvm] [ 89.138830] kvm_arch_vcpu_put+0xe6/0x170 [kvm] [ 89.138870] kvm_sched_out+0x2f/0x40 [kvm] [ 89.138900] __schedule+0x5de/0xbd0 Cc: stable@vger.kernel.org Reported-by: syzbot+b282b65c2c68492df769@syzkaller.appspotmail.com Fixes: 30b5c851 ("KVM: x86/xen: Add support for vCPU runstate information") Signed-off-by: -
David Edmondson authored
When passing the failing address and size out to user space, SGX must ensure not to trample on the earlier fields of the emulation_failure sub-union of struct kvm_run. Signed-off-by:
David Edmondson <david.edmondson@oracle.com> Reviewed-by:
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David Edmondson authored
Should instruction emulation fail, include the VM exit reason, etc. in the emulation_failure data passed to userspace, in order that the VMM can report it as a debugging aid when describing the failure. Suggested-by:
Joao Martins <joao.m.martins@oracle.com> Signed-off-by:
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David Edmondson authored
Extend the get_exit_info static call to provide the reason for the VM exit. Modify relevant trace points to use this rather than extracting the reason in the caller. Signed-off-by:
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David Edmondson authored
Until more flags for kvm_run.emulation_failure flags are defined, it is undetermined whether new payload elements corresponding to those flags will be additive or alternative. As a hint to userspace that an alternative is possible, wrap the current payload elements in a union. Suggested-by:
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Eric Farman authored
This capability exists, but we don't record anything when userspace enables it. Let's refactor that code so that a note can be made in the debug logs that it was enabled. Signed-off-by:
Eric Farman <farman@linux.ibm.com> Reviewed-by:
Thomas Huth <thuth@redhat.com> Reviewed-by:
David Hildenbrand <david@redhat.com> Link: https://lore.kernel.org/r/20211008203112.1979843-7-farman@linux.ibm.comSigned-off-by:
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Eric Farman authored
The Principles of Operations describe the various reasons that each individual SIGP orders might be rejected, and the status bit that are set for each condition. For example, for the Set Architecture order, it states: "If it is not true that all other CPUs in the configu- ration are in the stopped or check-stop state, ... bit 54 (incorrect state) ... is set to one." However, it also states: "... if the CZAM facility is installed, ... bit 55 (invalid parameter) ... is set to one." Since the Configuration-z/Architecture-Architectural Mode (CZAM) facility is unconditionally presented, there is no need to examine each VCPU to determine if it is started/stopped. It can simply be rejected outright with the Invalid Parameter bit. Fixes: b697e435 ("KVM: s390: Support Configuration z/Architecture Mode") Signed-off-by:
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Claudio Imbrenda authored
Improve make_secure_pte to avoid stalls when the system is heavily overcommitted. This was especially problematic in kvm_s390_pv_unpack, because of the loop over all pages that needed unpacking. Due to the locks being held, it was not possible to simply replace uv_call with uv_call_sched. A more complex approach was needed, in which uv_call is replaced with __uv_call, which does not loop. When the UVC needs to be executed again, -EAGAIN is returned, and the caller (or its caller) will try again. When -EAGAIN is returned, the path is the same as when the page is in writeback (and the writeback check is also performed, which is harmless). Fixes: 214d9bbc ("s390/mm: provide memory management functions for protected KVM guests") Signed-off-by:
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