- 13 Apr, 2022 19 commits
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Sean Christopherson authored
Use the recently introduced __try_cmpxchg_user() to update guest PTE A/D bits instead of mapping the PTE into kernel address space. The VM_PFNMAP path is broken as it assumes that vm_pgoff is the base pfn of the mapped VMA range, which is conceptually wrong as vm_pgoff is the offset relative to the file and has nothing to do with the pfn. The horrific hack worked for the original use case (backing guest memory with /dev/mem), but leads to accessing "random" pfns for pretty much any other VM_PFNMAP case. Fixes: bd53cb35 ("X86/KVM: Handle PFNs outside of kernel reach when touching GPTEs") Debugged-by:
Tadeusz Struk <tadeusz.struk@linaro.org> Tested-by:
Sean Christopherson <seanjc@google.com> Message-Id: <20220202004945.2540433-4-seanjc@google.com> Signed-off-by:
Paolo Bonzini <pbonzini@redhat.com>
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Peter Zijlstra authored
Add support for CMPXCHG loops on userspace addresses. Provide both an "unsafe" version for tight loops that do their own uaccess begin/end, as well as a "safe" version for use cases where the CMPXCHG is not buried in a loop, e.g. KVM will resume the guest instead of looping when emulation of a guest atomic accesses fails the CMPXCHG. Provide 8-byte versions for 32-bit kernels so that KVM can do CMPXCHG on guest PAE PTEs, which are accessed via userspace addresses. Guard the asm_volatile_goto() variation with CC_HAS_ASM_GOTO_TIED_OUTPUT, the "+m" constraint fails on some compilers that otherwise support CC_HAS_ASM_GOTO_OUTPUT. Cc: stable@vger.kernel.org Signed-off-by:
Peter Zijlstra (Intel) <peterz@infradead.org> Co-developed-by:
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Sean Christopherson authored
Add a config option to guard (future) usage of asm_volatile_goto() that includes "tied outputs", i.e. "+" constraints that specify both an input and output parameter. clang-13 has a bug[1] that causes compilation of such inline asm to fail, and KVM wants to use a "+m" constraint to implement a uaccess form of CMPXCHG[2]. E.g. the test code fails with <stdin>:1:29: error: invalid operand in inline asm: '.long (${1:l}) - .' int foo(int *x) { asm goto (".long (%l[bar]) - .\n": "+m"(*x) ::: bar); return *x; bar: return 0; } ^ <stdin>:1:29: error: unknown token in expression <inline asm>:1:9: note: instantiated into assembly here .long () - . ^ 2 errors generated. on clang-13, but passes on gcc (with appropriate asm goto support). The bug is fixed in clang-14, but won't be backported to clang-13 as the changes are too invasive/risky. gcc also had a similar bug[3], fixed in gcc-11, where gcc failed to account for its behavior of assigning two numbers to tied outputs (one for input, one for output) when evaluating symbolic references. [1] https://github.com/ClangBuiltLinux/linux/issues/1512 [2] https://lore.kernel.org/all/YfMruK8%2F1izZ2VHS@google.com [3] https://gcc.gnu.org/bugzilla/show_bug.cgi?id=98096Suggested-by:Nick Desaulniers <ndesaulniers@google.com> Reviewed-by:
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Peter Gonda authored
If an SEV-ES guest requests termination, exit to userspace with KVM_EXIT_SYSTEM_EVENT and a dedicated SEV_TERM type instead of -EINVAL so that userspace can take appropriate action. See AMD's GHCB spec section '4.1.13 Termination Request' for more details. Suggested-by:
Peter Gonda <pgonda@google.com> Reported-by:
kernel test robot <lkp@intel.com> Message-Id: <20220407210233.782250-1-pgonda@google.com> [Add documentatino. - Paolo] Signed-off-by:
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Sean Christopherson authored
Clear the IDT vectoring field in vmcs12 on next VM-Exit due to a double or triple fault. Per the SDM, a VM-Exit isn't considered to occur during event delivery if the exit is due to an intercepted double fault or a triple fault. Opportunistically move the default clearing (no event "pending") into the helper so that it's more obvious that KVM does indeed handle this case. Note, the double fault case is worded rather wierdly in the SDM: The original event results in a double-fault exception that causes the VM exit directly. Temporarily ignoring injected events, double faults can _only_ occur if an exception occurs while attempting to deliver a different exception, i.e. there's _always_ an original event. And for injected double fault, while there's no original event, injected events are never subject to interception. Presumably the SDM is calling out that a the vectoring info will be valid if a different exit occurs after a double fault, e.g. if a #PF occurs and is intercepted while vectoring #DF, then the vectoring info will show the double fault. In other words, the clause can simply be read as: The VM exit is caused by a double-fault exception. Fixes: 4704d0be ("KVM: nVMX: Exiting from L2 to L1") Cc: Chenyi Qiang <chenyi.qiang@intel.com> Signed-off-by:
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Sean Christopherson authored
Don't modify vmcs12 exit fields except EXIT_REASON and EXIT_QUALIFICATION when performing a nested VM-Exit due to failed VM-Entry. Per the SDM, only the two aformentioned fields are filled and "All other VM-exit information fields are unmodified". Fixes: 4704d0be ("KVM: nVMX: Exiting from L2 to L1") Signed-off-by:
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Sean Christopherson authored
Remove WARNs that sanity check that KVM never lets a triple fault for L2 escape and incorrectly end up in L1. In normal operation, the sanity check is perfectly valid, but it incorrectly assumes that it's impossible for userspace to induce KVM_REQ_TRIPLE_FAULT without bouncing through KVM_RUN (which guarantees kvm_check_nested_state() will see and handle the triple fault). The WARN can currently be triggered if userspace injects a machine check while L2 is active and CR4.MCE=0. And a future fix to allow save/restore of KVM_REQ_TRIPLE_FAULT, e.g. so that a synthesized triple fault isn't lost on migration, will make it trivially easy for userspace to trigger the WARN. Clearing KVM_REQ_TRIPLE_FAULT when forcibly leaving guest mode is tempting, but wrong, especially if/when the request is saved/restored, e.g. if userspace restores events (including a triple fault) and then restores nested state (which may forcibly leave guest mode). Ignoring the fact that KVM doesn't currently provide the necessary APIs, it's userspace's responsibility to manage pending events during save/restore. ------------[ cut here ]------------ WARNING: CPU: 7 PID: 1399 at arch/x86/kvm/vmx/nested.c:4522 nested_vmx_vmexit+0x7fe/0xd90 [kvm_intel] Modules linked in: kvm_intel kvm irqbypass CPU: 7 PID: 1399 Comm: state_test Not tainted 5.17.0-rc3+ #808 Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS 0.0.0 02/06/2015 RIP: 0010:nested_vmx_vmexit+0x7fe/0xd90 [kvm_intel] Call Trace: <TASK> vmx_leave_nested+0x30/0x40 [kvm_intel] vmx_set_nested_state+0xca/0x3e0 [kvm_intel] kvm_arch_vcpu_ioctl+0xf49/0x13e0 [kvm] kvm_vcpu_ioctl+0x4b9/0x660 [kvm] __x64_sys_ioctl+0x83/0xb0 do_syscall_64+0x3b/0xc0 entry_SYSCALL_64_after_hwframe+0x44/0xae </TASK> ---[ end trace 0000000000000000 ]--- Fixes: cb6a32c2 ("KVM: x86: Handle triple fault in L2 without killing L1") Cc: stable@vger.kernel.org Cc: Chenyi Qiang <chenyi.qiang@intel.com> Signed-off-by:
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Like Xu authored
Use static calls to improve kvm_pmu_ops performance, following the same pattern and naming scheme used by kvm-x86-ops.h. Here are the worst fenced_rdtsc() cycles numbers for the kvm_pmu_ops functions that is most often called (up to 7 digits of calls) when running a single perf test case in a guest on an ICX 2.70GHz host (mitigations=on): | legacy | static call ------------------------------------------------------------ .pmc_idx_to_pmc | 1304840 | 994872 (+23%) .pmc_is_enabled | 978670 | 1011750 (-3%) .msr_idx_to_pmc | 47828 | 41690 (+12%) .is_valid_msr | 28786 | 30108 (-4%) Signed-off-by:
Like Xu <likexu@tencent.com> [sean: Handle static call updates in pmu.c, tweak changelog] Signed-off-by:
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Like Xu authored
The pmu_ops should be moved to kvm_x86_init_ops and tagged as __initdata. That'll save those precious few bytes, and more importantly make the original ops unreachable, i.e. make it harder to sneak in post-init modification bugs. Suggested-by:
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Like Xu authored
Replace the kvm_pmu_ops pointer in common x86 with an instance of the struct to save one pointer dereference when invoking functions. Copy the struct by value to set the ops during kvm_init(). Signed-off-by:
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Like Xu authored
The kvm_ops_static_call_update() is defined in kvm_host.h. That's completely unnecessary, it should have exactly one caller, kvm_arch_hardware_setup(). Move the helper to x86.c and have it do the actual memcpy() of the ops in addition to the static call updates. This will also allow for cleanly giving kvm_pmu_ops static_call treatment. Suggested-by:
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Sean Christopherson authored
Derive the mask of RWX bits reported on EPT violations from the mask of RWX bits that are shoved into EPT entries; the layout is the same, the EPT violation bits are simply shifted by three. Use the new shift and a slight copy-paste of the mask derivation instead of completely open coding the same to convert between the EPT entry bits and the exit qualification when synthesizing a nested EPT Violation. No functional change intended. Cc: SU Hang <darcy.sh@antgroup.com> Signed-off-by:
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SU Hang authored
Using self-expressing macro definition EPT_VIOLATION_GVA_VALIDATION and EPT_VIOLATION_GVA_TRANSLATED instead of 0x180 in FNAME(walk_addr_generic)(). Signed-off-by:
SU Hang <darcy.sh@antgroup.com> Reviewed-by:
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Wanpeng Li authored
When the "nopv" command line parameter is used, it should not waste memory for kvmclock. Signed-off-by:
Wanpeng Li <wanpengli@tencent.com> Message-Id: <1646727529-11774-1-git-send-email-wanpengli@tencent.com> Signed-off-by:
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Peng Hao authored
Remove redundant parentheses. Signed-off-by:
Peng Hao <flyingpeng@tencent.com> Message-Id: <20220228030902.88465-1-flyingpeng@tencent.com> Signed-off-by:
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Peng Hao authored
Adjust the field pkru_mask to the back of direct_map to make up 8-byte alignment.This reduces the size of kvm_mmu by 8 bytes. Signed-off-by:
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Like Xu authored
+WARNING: Possible comma where semicolon could be used +#397: FILE: tools/testing/selftests/kvm/x86_64/xen_shinfo_test.c:700: ++ tmr.type = KVM_XEN_VCPU_ATTR_TYPE_TIMER, ++ vcpu_ioctl(vm, VCPU_ID, KVM_XEN_VCPU_GET_ATTR, &tmr); Fixes: 25eaeebe ("KVM: x86/xen: Add self tests for KVM_XEN_HVM_CONFIG_EVTCHN_SEND") Signed-off-by:
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Like Xu authored
The header lapic.h is included more than once, remove one of them. Signed-off-by:
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Paolo Bonzini authored
Merge branch for features that did not make it into 5.18: * New ioctls to get/set TSC frequency for a whole VM * Allow userspace to opt out of hypercall patching Nested virtualization improvements for AMD: * Support for "nested nested" optimizations (nested vVMLOAD/VMSAVE, nested vGIF) * Allow AVIC to co-exist with a nested guest running * Fixes for LBR virtualizations when a nested guest is running, and nested LBR virtualization support * PAUSE filtering for nested hypervisors Guest support: * Decoupling of vcpu_is_preempted from PV spinlocks Signed-off-by:
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- 11 Apr, 2022 5 commits
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Vitaly Kuznetsov authored
The following WARN is triggered from kvm_vm_ioctl_set_clock(): WARNING: CPU: 10 PID: 579353 at arch/x86/kvm/../../../virt/kvm/kvm_main.c:3161 mark_page_dirty_in_slot+0x6c/0x80 [kvm] ... CPU: 10 PID: 579353 Comm: qemu-system-x86 Tainted: G W O 5.16.0.stable #20 Hardware name: LENOVO 20UF001CUS/20UF001CUS, BIOS R1CET65W(1.34 ) 06/17/2021 RIP: 0010:mark_page_dirty_in_slot+0x6c/0x80 [kvm] ... Call Trace: <TASK> ? kvm_write_guest+0x114/0x120 [kvm] kvm_hv_invalidate_tsc_page+0x9e/0xf0 [kvm] kvm_arch_vm_ioctl+0xa26/0xc50 [kvm] ? schedule+0x4e/0xc0 ? __cond_resched+0x1a/0x50 ? futex_wait+0x166/0x250 ? __send_signal+0x1f1/0x3d0 kvm_vm_ioctl+0x747/0xda0 [kvm] ... The WARN was introduced by commit 03c0304a86bc ("KVM: Warn if mark_page_dirty() is called without an active vCPU") but the change seems to be correct (unlike Hyper-V TSC page update mechanism). In fact, there's no real need to actually write to guest memory to invalidate TSC page, this can be done by the first vCPU which goes through kvm_guest_time_update(). Reported-by:Maxim Levitsky <mlevitsk@redhat.com> Reported-by:
Naresh Kamboju <naresh.kamboju@linaro.org> Suggested-by:
Vitaly Kuznetsov <vkuznets@redhat.com> Message-Id: <20220407201013.963226-1-vkuznets@redhat.com>
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Suravee Suthikulpanit authored
Since current AVIC implementation cannot support encrypted memory, inhibit AVIC for SEV-enabled guest. Signed-off-by:
Suravee Suthikulpanit <suravee.suthikulpanit@amd.com> Message-Id: <20220408133710.54275-1-suravee.suthikulpanit@amd.com> Signed-off-by:
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Like Xu authored
+new file mode 100644 +WARNING: Missing or malformed SPDX-License-Identifier tag in line 1 +#27: FILE: Documentation/virt/kvm/x86/errata.rst:1: Opportunistically update all other non-added KVM documents and remove a new extra blank line at EOF for x86/errata.rst. Signed-off-by:
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Like Xu authored
The tsc_scaling_sync's binary should be present in the .gitignore file for the git to ignore it. Signed-off-by:
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https://github.com/kvm-riscv/linuxPaolo Bonzini authored
KVM/riscv fixes for 5.18, take #1 - Remove hgatp zeroing in kvm_arch_vcpu_put() - Fix alignment of the guest_hang() in KVM selftest - Fix PTE A and D bits in KVM selftest - Missing #include in vcpu_fp.c
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- 09 Apr, 2022 4 commits
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Heiko Stuebner authored
vcpu_fp uses the riscv_isa_extension mechanism which gets defined in hwcap.h but doesn't include that head file. While it seems to work in most cases, in certain conditions this can lead to build failures like ../arch/riscv/kvm/vcpu_fp.c: In function ‘kvm_riscv_vcpu_fp_reset’: ../arch/riscv/kvm/vcpu_fp.c:22:13: error: implicit declaration of function ‘riscv_isa_extension_available’ [-Werror=implicit-function-declaration] 22 | if (riscv_isa_extension_available(&isa, f) || | ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~ ../arch/riscv/kvm/vcpu_fp.c:22:49: error: ‘f’ undeclared (first use in this function) 22 | if (riscv_isa_extension_available(&isa, f) || Fix this by simply including the necessary header. Fixes: 0a86512d ("RISC-V: KVM: Factor-out FP virtualization into separate sources") Signed-off-by:Heiko Stuebner <heiko@sntech.de> Signed-off-by:
Anup Patel <anup@brainfault.org>
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Anup Patel authored
The guest_hang() function is used as the default exception handler for various KVM selftests applications by setting it's address in the vstvec CSR. The vstvec CSR requires exception handler base address to be at least 4-byte aligned so this patch fixes alignment of the guest_hang() function. Fixes: 3e06cdf1 ("KVM: selftests: Add initial support for RISC-V 64-bit") Signed-off-by:
Anup Patel <apatel@ventanamicro.com> Tested-by:
Mayuresh Chitale <mchitale@ventanamicro.com> Signed-off-by:
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Anup Patel authored
Supporting hardware updates of PTE A and D bits is optional for any RISC-V implementation so current software strategy is to always set these bits in both G-stage (hypervisor) and VS-stage (guest kernel). If PTE A and D bits are not set by software (hypervisor or guest) then RISC-V implementations not supporting hardware updates of these bits will cause traps even for perfectly valid PTEs. Based on above explanation, the VS-stage page table created by various KVM selftest applications is not correct because PTE A and D bits are not set. This patch fixes VS-stage page table programming of PTE A and D bits for KVM selftests. Fixes: 3e06cdf1 ("KVM: selftests: Add initial support for RISC-V 64-bit") Signed-off-by:
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Anup Patel authored
We might have RISC-V systems (such as QEMU) where VMID is not part of the TLB entry tag so these systems will have to flush all TLB entries upon any change in hgatp.VMID. Currently, we zero-out hgatp CSR in kvm_arch_vcpu_put() and we re-program hgatp CSR in kvm_arch_vcpu_load(). For above described systems, this will flush all TLB entries whenever VCPU exits to user-space hence reducing performance. This patch fixes above described performance issue by not clearing hgatp CSR in kvm_arch_vcpu_put(). Fixes: 34bde9d8 ("RISC-V: KVM: Implement VCPU world-switch") Cc: stable@vger.kernel.org Signed-off-by:
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- 08 Apr, 2022 1 commit
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Paolo Bonzini authored
Merge tag 'kvmarm-fixes-5.18-1' of git://git.kernel.org/pub/scm/linux/kernel/git/kvmarm/kvmarm into HEAD KVM/arm64 fixes for 5.18, take #1 - Some PSCI fixes after introducing PSCIv1.1 and SYSTEM_RESET2 - Fix the MMU write-lock not being taken on THP split - Fix mixed-width VM handling - Fix potential UAF when debugfs registration fails - Various selftest updates for all of the above
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- 07 Apr, 2022 4 commits
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Oliver Upton authored
In order to correctly destroy a VM, all references to the VM must be freed. The arch_timer selftest creates a VGIC for the guest, which itself holds a reference to the VM. Close the GIC FD when cleaning up a VM. Signed-off-by:
Oliver Upton <oupton@google.com> Signed-off-by:
Marc Zyngier <maz@kernel.org> Link: https://lore.kernel.org/r/20220406235615.1447180-4-oupton@google.com
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Oliver Upton authored
dirty_log_perf_test instantiates a VGICv3 for the guest (if supported by hardware) to reduce the overhead of guest exits. However, the test does not actually close the GIC fd when cleaning up the VM between test iterations, meaning that the VM is never actually destroyed in the kernel. While this is generally a bad idea, the bug was detected from the kernel spewing about duplicate debugfs entries as subsequent VMs happen to reuse the same FD even though the debugfs directory is still present. Abstract away the notion of setup/cleanup of the GIC FD from the test by creating arch-specific helpers for test setup/cleanup. Close the GIC FD on VM cleanup and do nothing for the other architectures. Fixes: c340f789 ("KVM: selftests: Add vgic initialization for dirty log perf test for ARM") Reviewed-by:
Jing Zhang <jingzhangos@google.com> Signed-off-by:
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Oliver Upton authored
Unfortunately, there is no guarantee that KVM was able to instantiate a debugfs directory for a particular VM. To that end, KVM shouldn't even attempt to create new debugfs files in this case. If the specified parent dentry is NULL, debugfs_create_file() will instantiate files at the root of debugfs. For arm64, it is possible to create the vgic-state file outside of a VM directory, the file is not cleaned up when a VM is destroyed. Nonetheless, the corresponding struct kvm is freed when the VM is destroyed. Nip the problem in the bud for all possible errant debugfs file creations by initializing kvm->debugfs_dentry to -ENOENT. In so doing, debugfs_create_file() will fail instead of creating the file in the root directory. Cc: stable@kernel.org Fixes: 929f45e3 ("kvm: no need to check return value of debugfs_create functions") Signed-off-by:
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Andrew Jones authored
When testing a kernel with commit a5905d6a ("KVM: arm64: Allow SMCCC_ARCH_WORKAROUND_3 to be discovered and migrated") get-reg-list output vregs: Number blessed registers: 234 vregs: Number registers: 238 vregs: There are 1 new registers. Consider adding them to the blessed reg list with the following lines: KVM_REG_ARM_FW_REG(3), vregs: PASS ... That output inspired two changes: 1) add the new register to the blessed list and 2) explain why "Number registers" is actually four larger than "Number blessed registers" (on the system used for testing), even though only one register is being stated as new. The reason is that some registers are host dependent and they get filtered out when comparing with the blessed list. The system used for the test apparently had three filtered registers. Signed-off-by:
Andrew Jones <drjones@redhat.com> Acked-by:
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- 06 Apr, 2022 7 commits
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Paolo Bonzini authored
kvm_vcpu_release() will call kvm_dirty_ring_free(), freeing ring->dirty_gfns and setting it to NULL. Afterwards, it calls kvm_arch_vcpu_destroy(). However, if closing the file descriptor races with KVM_RUN in such away that vcpu->arch.st.preempted == 0, the following call stack leads to a NULL pointer dereference in kvm_dirty_run_push(): mark_page_dirty_in_slot+0x192/0x270 arch/x86/kvm/../../../virt/kvm/kvm_main.c:3171 kvm_steal_time_set_preempted arch/x86/kvm/x86.c:4600 [inline] kvm_arch_vcpu_put+0x34e/0x5b0 arch/x86/kvm/x86.c:4618 vcpu_put+0x1b/0x70 arch/x86/kvm/../../../virt/kvm/kvm_main.c:211 vmx_free_vcpu+0xcb/0x130 arch/x86/kvm/vmx/vmx.c:6985 kvm_arch_vcpu_destroy+0x76/0x290 arch/x86/kvm/x86.c:11219 kvm_vcpu_destroy arch/x86/kvm/../../../virt/kvm/kvm_main.c:441 [inline] The fix is to release the dirty page ring after kvm_arch_vcpu_destroy has run. Reported-by:
Qiuhao Li <qiuhao@sysec.org> Reported-by:
Gaoning Pan <pgn@zju.edu.cn> Reported-by:
Yongkang Jia <kangel@zju.edu.cn> Cc: stable@vger.kernel.org Signed-off-by:
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Reiji Watanabe authored
Introduce a test for aarch64 that ensures non-mixed-width vCPUs (all 64bit vCPUs or all 32bit vcPUs) can be configured, and mixed-width vCPUs cannot be configured. Reviewed-by:
Reiji Watanabe <reijiw@google.com> Reviewed-by:
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Reiji Watanabe authored
KVM allows userspace to configure either all EL1 32bit or 64bit vCPUs for a guest. At vCPU reset, vcpu_allowed_register_width() checks if the vcpu's register width is consistent with all other vCPUs'. Since the checking is done even against vCPUs that are not initialized (KVM_ARM_VCPU_INIT has not been done) yet, the uninitialized vCPUs are erroneously treated as 64bit vCPU, which causes the function to incorrectly detect a mixed-width VM. Introduce KVM_ARCH_FLAG_EL1_32BIT and KVM_ARCH_FLAG_REG_WIDTH_CONFIGURED bits for kvm->arch.flags. A value of the EL1_32BIT bit indicates that the guest needs to be configured with all 32bit or 64bit vCPUs, and a value of the REG_WIDTH_CONFIGURED bit indicates if a value of the EL1_32BIT bit is valid (already set up). Values in those bits are set at the first KVM_ARM_VCPU_INIT for the guest based on KVM_ARM_VCPU_EL1_32BIT configuration for the vCPU. Check vcpu's register width against those new bits at the vcpu's KVM_ARM_VCPU_INIT (instead of against other vCPUs' register width). Fixes: 66e94d5c ("KVM: arm64: Prevent mixed-width VM creation") Signed-off-by:
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Yu Zhe authored
Remove unnecessary casts. Signed-off-by:
Yu Zhe <yuzhe@nfschina.com> Signed-off-by:
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Oliver Upton authored
It is possible to take a stage-2 permission fault on a page larger than PAGE_SIZE. For example, when running a guest backed by 2M HugeTLB, KVM eagerly maps at the largest possible block size. When dirty logging is enabled on a memslot, KVM does *not* eagerly split these 2M stage-2 mappings and instead clears the write bit on the pte. Since dirty logging is always performed at PAGE_SIZE granularity, KVM lazily splits these 2M block mappings down to PAGE_SIZE in the stage-2 fault handler. This operation must be done under the write lock. Since commit f783ef1c ("KVM: arm64: Add fast path to handle permission relaxation during dirty logging"), the stage-2 fault handler conditionally takes the read lock on permission faults with dirty logging enabled. To that end, it is possible to split a 2M block mapping while only holding the read lock. The problem is demonstrated by running kvm_page_table_test with 2M anonymous HugeTLB, which splats like so: WARNING: CPU: 5 PID: 15276 at arch/arm64/kvm/hyp/pgtable.c:153 stage2_map_walk_leaf+0x124/0x158 [...] Call trace: stage2_map_walk_leaf+0x124/0x158 stage2_map_walker+0x5c/0xf0 __kvm_pgtable_walk+0x100/0x1d4 __kvm_pgtable_walk+0x140/0x1d4 __kvm_pgtable_walk+0x140/0x1d4 kvm_pgtable_walk+0xa0/0xf8 kvm_pgtable_stage2_map+0x15c/0x198 user_mem_abort+0x56c/0x838 kvm_handle_guest_abort+0x1fc/0x2a4 handle_exit+0xa4/0x120 kvm_arch_vcpu_ioctl_run+0x200/0x448 kvm_vcpu_ioctl+0x588/0x664 __arm64_sys_ioctl+0x9c/0xd4 invoke_syscall+0x4c/0x144 el0_svc_common+0xc4/0x190 do_el0_svc+0x30/0x8c el0_svc+0x28/0xcc el0t_64_sync_handler+0x84/0xe4 el0t_64_sync+0x1a4/0x1a8 Fix the issue by only acquiring the read lock if the guest faulted on a PAGE_SIZE granule w/ dirty logging enabled. Add a WARN to catch locking bugs in future changes. Fixes: f783ef1c ("KVM: arm64: Add fast path to handle permission relaxation during dirty logging") Cc: Jing Zhang <jingzhangos@google.com> Signed-off-by:
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Oliver Upton authored
We already sanitize the guest's PSCI version when it is being written by userspace, rejecting unsupported version numbers. Additionally, the 'minor' parameter to kvm_psci_1_x_call() is a constant known at compile time for all callsites. Though it is benign, the additional check against the PSCI kvm_psci_1_x_call() is unnecessary and likely to be missed the next time KVM raises its maximum PSCI version. Drop the check altogether and rely on sanitization when the PSCI version is set by userspace. No functional change intended. Signed-off-by:
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Oliver Upton authored
The SMCCC does not allow the SMC64 calling convention to be used from AArch32. While KVM checks to see if the calling convention is allowed in PSCI_1_0_FN_PSCI_FEATURES, it does not actually prevent calls to unadvertised PSCI v1.0+ functions. Hoist the check to see if the requested function is allowed into kvm_psci_call(), thereby preventing SMC64 calls from AArch32 for all PSCI versions. Fixes: d43583b8 ("KVM: arm64: Expose PSCI SYSTEM_RESET2 call to the guest") Acked-by:
Will Deacon <will@kernel.org> Reviewed-by:
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