- 28 Sep, 2020 36 commits
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Sean Christopherson authored
On successful nested VM-Enter, check for pending interrupts and convert the highest priority interrupt to a pending posted interrupt if it matches L2's notification vector. If the vCPU receives a notification interrupt before nested VM-Enter (assuming L1 disables IRQs before doing VM-Enter), the pending interrupt (for L1) should be recognized and processed as a posted interrupt when interrupts become unblocked after VM-Enter to L2. This fixes a bug where L1/L2 will get stuck in an infinite loop if L1 is trying to inject an interrupt into L2 by setting the appropriate bit in L2's PIR and sending a self-IPI prior to VM-Enter (as opposed to KVM's method of manually moving the vector from PIR->vIRR/RVI). KVM will observe the IPI while the vCPU is in L1 context and so won't immediately morph it to a posted interrupt for L2. The pending interrupt will be seen by vmx_check_nested_events(), cause KVM to force an immediate exit after nested VM-Enter, and eventually be reflected to L1 as a VM-Exit. After handling the VM-Exit, L1 will see that L2 has a pending interrupt in PIR, send another IPI, and repeat until L2 is killed. Note, posted interrupts require virtual interrupt deliveriy, and virtual interrupt delivery requires exit-on-interrupt, ergo interrupts will be unconditionally unmasked on VM-Enter if posted interrupts are enabled. Fixes: 705699a1 ("KVM: nVMX: Enable nested posted interrupt processing") Cc: stable@vger.kernel.org Cc: Liran Alon <liran.alon@oracle.com> Signed-off-by:
Sean Christopherson <sean.j.christopherson@intel.com> Message-Id: <20200812175129.12172-1-sean.j.christopherson@intel.com> Signed-off-by:
Paolo Bonzini <pbonzini@redhat.com>
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Tianjia Zhang authored
In the current kvm version, 'kvm_run' has been included in the 'kvm_vcpu' structure. For historical reasons, many kvm-related function parameters retain the 'kvm_run' and 'kvm_vcpu' parameters at the same time. This patch does a unified cleanup of these remaining redundant parameters. Signed-off-by:
Tianjia Zhang <tianjia.zhang@linux.alibaba.com> Reviewed-by:
Huacai Chen <chenhc@lemote.com> Tested-by:
Jiaxun Yang <jiaxun.yang@flygoat.com> Message-Id: <20200623131418.31473-6-tianjia.zhang@linux.alibaba.com> Signed-off-by:
Paolo Bonzini <pbonzini@redhat.com>
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Haiwei Li authored
Add trace_kvm_cr_write and trace_kvm_cr_read for svm. Signed-off-by:
Haiwei Li <lihaiwei@tencent.com> Message-Id: <f3031602-db3b-c4fe-b719-d402663b0a2b@gmail.com> Signed-off-by:
Paolo Bonzini <pbonzini@redhat.com>
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Wanpeng Li authored
Analyze is_guest_mode() in svm_vcpu_run() instead of svm_exit_handlers_fastpath() in conformity with VMX version. Suggested-by:
Vitaly Kuznetsov <vkuznets@redhat.com> Signed-off-by:
Wanpeng Li <wanpengli@tencent.com> Message-Id: <1600066548-4343-1-git-send-email-wanpengli@tencent.com> Signed-off-by:
Paolo Bonzini <pbonzini@redhat.com>
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Sean Christopherson authored
Rework NMI VM-Exit handling to invoke the kernel handler by function call instead of INTn. INTn microcode is relatively expensive, and aligning the IRQ and NMI handling will make it easier to update KVM should some newfangled method for invoking the handlers come along. Suggested-by:
Andi Kleen <ak@linux.intel.com> Signed-off-by:
Sean Christopherson <sean.j.christopherson@intel.com> Message-Id: <20200915191505.10355-3-sean.j.christopherson@intel.com> Signed-off-by:
Paolo Bonzini <pbonzini@redhat.com>
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Sean Christopherson authored
Move the asm blob that invokes the appropriate IRQ handler after VM-Exit into a proper subroutine. Unconditionally create a stack frame in the subroutine so that, as objtool sees things, the function has standard stack behavior. The dynamic stack adjustment makes using unwind hints problematic. Suggested-by:
Josh Poimboeuf <jpoimboe@redhat.com> Cc: Uros Bizjak <ubizjak@gmail.com> Signed-off-by:
Sean Christopherson <sean.j.christopherson@intel.com> Message-Id: <20200915191505.10355-2-sean.j.christopherson@intel.com> Signed-off-by:
Paolo Bonzini <pbonzini@redhat.com>
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Sean Christopherson authored
Replace the existing kvm_x86_ops.need_emulation_on_page_fault() with a more generic is_emulatable(), and unconditionally call the new function in x86_emulate_instruction(). KVM will use the generic hook to support multiple security related technologies that prevent emulation in one way or another. Similar to the existing AMD #NPF case where emulation of the current instruction is not possible due to lack of information, AMD's SEV-ES and Intel's SGX and TDX will introduce scenarios where emulation is impossible due to the guest's register state being inaccessible. And again similar to the existing #NPF case, emulation can be initiated by kvm_mmu_page_fault(), i.e. outside of the control of vendor-specific code. While the cause and architecturally visible behavior of the various cases are different, e.g. SGX will inject a #UD, AMD #NPF is a clean resume or complete shutdown, and SEV-ES and TDX "return" an error, the impact on the common emulation code is identical: KVM must stop emulation immediately and resume the guest. Query is_emulatable() in handle_ud() as well so that the force_emulation_prefix code doesn't incorrectly modify RIP before calling emulate_instruction() in the absurdly unlikely scenario that KVM encounters forced emulation in conjunction with "do not emulate". Cc: Tom Lendacky <thomas.lendacky@amd.com> Signed-off-by:
Sean Christopherson <sean.j.christopherson@intel.com> Message-Id: <20200915232702.15945-1-sean.j.christopherson@intel.com> Signed-off-by:
Paolo Bonzini <pbonzini@redhat.com>
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Haiwei Li authored
Use __GFP_ZERO while alloc_page(). Signed-off-by:
Haiwei Li <lihaiwei@tencent.com> Message-Id: <20200916083621.5512-1-lihaiwei.kernel@gmail.com> Signed-off-by:
Paolo Bonzini <pbonzini@redhat.com>
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Krish Sadhukhan authored
KVM: nVMX: KVM needs to unset "unrestricted guest" VM-execution control in vmcs02 if vmcs12 doesn't set it Currently, prepare_vmcs02_early() does not check if the "unrestricted guest" VM-execution control in vmcs12 is turned off and leaves the corresponding bit on in vmcs02. Due to this setting, vmentry checks which are supposed to render the nested guest state as invalid when this VM-execution control is not set, are passing in hardware. This patch turns off the "unrestricted guest" VM-execution control in vmcs02 if vmcs12 has turned it off. Suggested-by:
Jim Mattson <jmattson@google.com> Suggested-by:
Sean Christopherson <sean.j.christopherson@intel.com> Signed-off-by:
Krish Sadhukhan <krish.sadhukhan@oracle.com> Message-Id: <20200921081027.23047-2-krish.sadhukhan@oracle.com> Signed-off-by:
Paolo Bonzini <pbonzini@redhat.com>
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Maxim Levitsky authored
MSR reads/writes should always access the L1 state, since the (nested) hypervisor should intercept all the msrs it wants to adjust, and these that it doesn't should be read by the guest as if the host had read it. However IA32_TSC is an exception. Even when not intercepted, guest still reads the value + TSC offset. The write however does not take any TSC offset into account. This is documented in Intel's SDM and seems also to happen on AMD as well. This creates a problem when userspace wants to read the IA32_TSC value and then write it. (e.g for migration) In this case it reads L2 value but write is interpreted as an L1 value. To fix this make the userspace initiated reads of IA32_TSC return L1 value as well. Huge thanks to Dave Gilbert for helping me understand this very confusing semantic of MSR writes. Signed-off-by:
Maxim Levitsky <mlevitsk@redhat.com> Message-Id: <20200921103805.9102-2-mlevitsk@redhat.com> Signed-off-by:
Paolo Bonzini <pbonzini@redhat.com>
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Rustam Kovhaev authored
Make use of the struct_size() helper to avoid any potential type mistakes and protect against potential integer overflows Make use of the flex_array_size() helper to calculate the size of a flexible array member within an enclosing structure Suggested-by:
Gustavo A. R. Silva <gustavoars@kernel.org> Signed-off-by:
Rustam Kovhaev <rkovhaev@gmail.com> Message-Id: <20200918120500.954436-1-rkovhaev@gmail.com> Reviewed-by:
Gustavo A. R. Silva <gustavoars@kernel.org> Signed-off-by:
Paolo Bonzini <pbonzini@redhat.com>
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Babu Moger authored
The following intercept bit has been added to support VMEXIT for INVPCID instruction: Code Name Cause A2h VMEXIT_INVPCID INVPCID instruction The following bit has been added to the VMCB layout control area to control intercept of INVPCID: Byte Offset Bit(s) Function 14h 2 intercept INVPCID Enable the interceptions when the the guest is running with shadow page table enabled and handle the tlbflush based on the invpcid instruction type. For the guests with nested page table (NPT) support, the INVPCID feature works as running it natively. KVM does not need to do any special handling in this case. AMD documentation for INVPCID feature is available at "AMD64 Architecture Programmer’s Manual Volume 2: System Programming, Pub. 24593 Rev. 3.34(or later)" The documentation can be obtained at the links below: Link: https://www.amd.com/system/files/TechDocs/24593.pdf Link: https://bugzilla.kernel.org/show_bug.cgi?id=206537Signed-off-by:
Babu Moger <babu.moger@amd.com> Reviewed-by:
Jim Mattson <jmattson@google.com> Message-Id: <159985255929.11252.17346684135277453258.stgit@bmoger-ubuntu> Signed-off-by:
Paolo Bonzini <pbonzini@redhat.com>
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Babu Moger authored
INVPCID instruction handling is mostly same across both VMX and SVM. So, move the code to common x86.c. Signed-off-by:
Babu Moger <babu.moger@amd.com> Reviewed-by:
Jim Mattson <jmattson@google.com> Message-Id: <159985255212.11252.10322694343971983487.stgit@bmoger-ubuntu> Signed-off-by:
Paolo Bonzini <pbonzini@redhat.com>
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Babu Moger authored
Handling of kvm_read/write_guest_virt*() errors can be moved to common code. The same code can be used by both VMX and SVM. Signed-off-by:
Babu Moger <babu.moger@amd.com> Reviewed-by:
Jim Mattson <jmattson@google.com> Message-Id: <159985254493.11252.6603092560732507607.stgit@bmoger-ubuntu> Signed-off-by:
Paolo Bonzini <pbonzini@redhat.com>
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Babu Moger authored
Remove set_cr_intercept, clr_cr_intercept and is_cr_intercept. Instead call generic svm_set_intercept, svm_clr_intercept an dsvm_is_intercep tfor all cr intercepts. Signed-off-by:
Babu Moger <babu.moger@amd.com> Reviewed-by:
Jim Mattson <jmattson@google.com> Message-Id: <159985253016.11252.16945893859439811480.stgit@bmoger-ubuntu> Signed-off-by:
Paolo Bonzini <pbonzini@redhat.com>
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Babu Moger authored
The new intercept bits have been added in vmcb control area to support few more interceptions. Here are the some of them. - INTERCEPT_INVLPGB, - INTERCEPT_INVLPGB_ILLEGAL, - INTERCEPT_INVPCID, - INTERCEPT_MCOMMIT, - INTERCEPT_TLBSYNC, Add a new intercept word in vmcb_control_area to support these instructions. Also update kvm_nested_vmrun trace function to support the new addition. AMD documentation for these instructions is available at "AMD64 Architecture Programmer’s Manual Volume 2: System Programming, Pub. 24593 Rev. 3.34(or later)" The documentation can be obtained at the links below: Link: https://www.amd.com/system/files/TechDocs/24593.pdf Link: https://bugzilla.kernel.org/show_bug.cgi?id=206537Signed-off-by:
Babu Moger <babu.moger@amd.com> Reviewed-by:
Jim Mattson <jmattson@google.com> Message-Id: <159985251547.11252.16994139329949066945.stgit@bmoger-ubuntu> Signed-off-by:
Paolo Bonzini <pbonzini@redhat.com>
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Babu Moger authored
Convert all the intercepts to one array of 32 bit vectors in vmcb_control_area. This makes it easy for future intercept vector additions. Also update trace functions. Signed-off-by:
Babu Moger <babu.moger@amd.com> Reviewed-by:
Jim Mattson <jmattson@google.com> Message-Id: <159985250813.11252.5736581193881040525.stgit@bmoger-ubuntu> Signed-off-by:
Paolo Bonzini <pbonzini@redhat.com>
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Babu Moger authored
Modify intercept_exceptions to generic intercepts in vmcb_control_area. Use the generic vmcb_set_intercept, vmcb_clr_intercept and vmcb_is_intercept to set/clear/test the intercept_exceptions bits. Signed-off-by:
Babu Moger <babu.moger@amd.com> Reviewed-by:
Jim Mattson <jmattson@google.com> Message-Id: <159985250037.11252.1361972528657052410.stgit@bmoger-ubuntu> Signed-off-by:
Paolo Bonzini <pbonzini@redhat.com>
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Babu Moger authored
Modify intercept_dr to generic intercepts in vmcb_control_area. Use the generic vmcb_set_intercept, vmcb_clr_intercept and vmcb_is_intercept to set/clear/test the intercept_dr bits. Signed-off-by:
Babu Moger <babu.moger@amd.com> Reviewed-by:
Jim Mattson <jmattson@google.com> Message-Id: <159985249255.11252.10000868032136333355.stgit@bmoger-ubuntu> Signed-off-by:
Paolo Bonzini <pbonzini@redhat.com>
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Babu Moger authored
Change intercept_cr to generic intercepts in vmcb_control_area. Use the new vmcb_set_intercept, vmcb_clr_intercept and vmcb_is_intercept where applicable. Signed-off-by:
Babu Moger <babu.moger@amd.com> Reviewed-by:
Jim Mattson <jmattson@google.com> Message-Id: <159985248506.11252.9081085950784508671.stgit@bmoger-ubuntu> [Change constant names. - Paolo] Signed-off-by:
Paolo Bonzini <pbonzini@redhat.com>
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Babu Moger authored
This is in preparation for the future intercept vector additions. Add new functions vmcb_set_intercept, vmcb_clr_intercept and vmcb_is_intercept using kernel APIs __set_bit, __clear_bit and test_bit espectively. Signed-off-by:
Babu Moger <babu.moger@amd.com> Reviewed-by:
Jim Mattson <jmattson@google.com> Message-Id: <159985247876.11252.16039238014239824460.stgit@bmoger-ubuntu> Signed-off-by:
Paolo Bonzini <pbonzini@redhat.com>
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Babu Moger authored
host_intercept_exceptions is not used anywhere. Clean it up. Signed-off-by:
Babu Moger <babu.moger@amd.com> Reviewed-by:
Jim Mattson <jmattson@google.com> Message-Id: <159985252277.11252.8819848322175521354.stgit@bmoger-ubuntu> Signed-off-by:
Paolo Bonzini <pbonzini@redhat.com>
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Maxim Levitsky authored
Kernel coding style suggests not to use labels like error1,error2 Suggested-by:
Jim Mattson <jmattson@google.com> Signed-off-by:
Maxim Levitsky <mlevitsk@redhat.com> Message-Id: <20200827171145.374620-6-mlevitsk@redhat.com> Signed-off-by:
Paolo Bonzini <pbonzini@redhat.com>
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Maxim Levitsky authored
Another small refactoring. Suggested-by:
Jim Mattson <jmattson@google.com> Signed-off-by:
Maxim Levitsky <mlevitsk@redhat.com> Message-Id: <20200827171145.374620-5-mlevitsk@redhat.com> Signed-off-by:
Paolo Bonzini <pbonzini@redhat.com>
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Maxim Levitsky authored
Replace svm_vcpu_init_msrpm with svm_vcpu_alloc_msrpm, that also allocates the msr bitmap and add svm_vcpu_free_msrpm to free it. This will be used later to move the nested msr permission bitmap allocation to nested.c Signed-off-by:
Maxim Levitsky <mlevitsk@redhat.com> Message-Id: <20200827171145.374620-4-mlevitsk@redhat.com> Signed-off-by:
Paolo Bonzini <pbonzini@redhat.com>
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Maxim Levitsky authored
This is to be more consistient with VMX, and to support upcoming addition of vmcb02 Hopefully no functional changes. Signed-off-by:
Maxim Levitsky <mlevitsk@redhat.com> Message-Id: <20200827171145.374620-3-mlevitsk@redhat.com> Signed-off-by:
Paolo Bonzini <pbonzini@redhat.com>
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Maxim Levitsky authored
The 'page' is to hold the vcpu's vmcb so name it as such to avoid confusion. Signed-off-by:
Maxim Levitsky <mlevitsk@redhat.com> Reviewed-by:
Jim Mattson <jmattson@google.com> Message-Id: <20200827171145.374620-2-mlevitsk@redhat.com> Signed-off-by:
Paolo Bonzini <pbonzini@redhat.com>
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Wanpeng Li authored
All the checks in lapic_timer_int_injected(), __kvm_wait_lapic_expire(), and these function calls waste cpu cycles when the timer mode is not tscdeadline. We can observe ~1.3% world switch time overhead by kvm-unit-tests/vmexit.flat vmcall testing on AMD server. This patch reduces the world switch latency caused by timer_advance_ns feature when the timer mode is not tscdeadline by simpling move the check against apic->lapic_timer.expired_tscdeadline much earlier. Signed-off-by:
Wanpeng Li <wanpengli@tencent.com> Message-Id: <1599731444-3525-7-git-send-email-wanpengli@tencent.com> Signed-off-by:
Paolo Bonzini <pbonzini@redhat.com>
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Wanpeng Li authored
The kick after setting KVM_REQ_PENDING_TIMER is used to handle the timer fires on a different pCPU which vCPU is running on. This kick costs about 1000 clock cycles and we don't need this when injecting already-expired timer or when using the VMX preemption timer because kvm_lapic_expired_hv_timer() is called from the target vCPU. Reviewed-by:
Sean Christopherson <sean.j.christopherson@intel.com> Signed-off-by:
Wanpeng Li <wanpengli@tencent.com> Message-Id: <1599731444-3525-6-git-send-email-wanpengli@tencent.com> Signed-off-by:
Paolo Bonzini <pbonzini@redhat.com>
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Wanpeng Li authored
Check apic_lvtt_tscdeadline() mode directly instead of apic_lvtt_oneshot() and apic_lvtt_period() to guarantee the timer is in tsc-deadline mode when wrmsr MSR_IA32_TSCDEADLINE. Reviewed-by:
Sean Christopherson <sean.j.christopherson@intel.com> Signed-off-by:
Wanpeng Li <wanpengli@tencent.com> Message-Id: <1599731444-3525-3-git-send-email-wanpengli@tencent.com> Signed-off-by:
Paolo Bonzini <pbonzini@redhat.com>
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Wanpeng Li authored
Return 0 when getting the tscdeadline timer if the lapic is hw disabled. Suggested-by:
Paolo Bonzini <pbonzini@redhat.com> Reviewed-by:
Sean Christopherson <sean.j.christopherson@intel.com> Signed-off-by:
Wanpeng Li <wanpengli@tencent.com> Message-Id: <1599731444-3525-2-git-send-email-wanpengli@tencent.com> Signed-off-by:
Paolo Bonzini <pbonzini@redhat.com>
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Wanpeng Li authored
There is missing apic map recalculation after updating DFR, if it is INIT RESET, in x2apic mode, local apic is software enabled before. This patch fix it by introducing the function kvm_apic_set_dfr() to be called in INIT RESET handling path. Signed-off-by:
Wanpeng Li <wanpengli@tencent.com> Message-Id: <1597827327-25055-1-git-send-email-wanpengli@tencent.com> Signed-off-by:
Paolo Bonzini <pbonzini@redhat.com>
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Yi Li authored
There is no need to calculate wildcard in each iteration since wildcard is not changed. Signed-off-by:
Yi Li <yili@winhong.com> Message-Id: <20200911055652.3041762-1-yili@winhong.com> Signed-off-by:
Paolo Bonzini <pbonzini@redhat.com>
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Chenyi Qiang authored
The nested VMX controls MSRs can be initialized by the global capability values stored in vmcs_config. Signed-off-by:
Chenyi Qiang <chenyi.qiang@intel.com> Reviewed-by:
Xiaoyao Li <xiaoyao.li@intel.com> Message-Id: <20200828085622.8365-6-chenyi.qiang@intel.com> Signed-off-by:
Paolo Bonzini <pbonzini@redhat.com>
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Chenyi Qiang authored
KVM supports the nested VM_{EXIT, ENTRY}_LOAD_IA32_PERF_GLOBAL_CTRL and VM_{ENTRY_LOAD, EXIT_CLEAR}_BNDCFGS, but they are not exposed by the system ioctl KVM_GET_MSR. Add them to the setup of nested VMX controls MSR. Signed-off-by:
Chenyi Qiang <chenyi.qiang@intel.com> Message-Id: <20200828085622.8365-2-chenyi.qiang@intel.com> Reviewed-by:
Xiaoyao Li <xiaoyao.li@intel.com> Signed-off-by:
Paolo Bonzini <pbonzini@redhat.com>
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Vitaly Kuznetsov authored
The save and ctl pointers are passed uninitialized to kfree() when svm_set_nested_state() follows the 'goto out_set_gif' path. While the issue could've been fixed by initializing these on-stack varialbles to NULL, it seems preferable to eliminate 'out_set_gif' label completely as it is not actually a failure path and duplicating a single svm_set_gif() call doesn't look too bad. [ bp: Drop obscure Addresses-Coverity: tag. ] Fixes: 6ccbd29a ("KVM: SVM: nested: Don't allocate VMCB structures on stack") Reported-by:
Dan Carpenter <dan.carpenter@oracle.com> Reported-by:
Joerg Roedel <jroedel@suse.de> Reported-by:
Colin King <colin.king@canonical.com> Signed-off-by:
Vitaly Kuznetsov <vkuznets@redhat.com> Signed-off-by:
Borislav Petkov <bp@suse.de> Reviewed-by:
Sean Christopherson <sean.j.christopherson@intel.com> Acked-by:
Joerg Roedel <jroedel@suse.de> Tested-by:
Tom Lendacky <thomas.lendacky@amd.com> Link: https://lkml.kernel.org/r/20200914133725.650221-1-vkuznets@redhat.comSigned-off-by:
Paolo Bonzini <pbonzini@redhat.com>
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- 22 Sep, 2020 4 commits
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Paolo Bonzini authored
Merge tag 'kvm-ppc-next-5.10-1' of git://git.kernel.org/pub/scm/linux/kernel/git/paulus/powerpc into HEAD PPC KVM update for 5.10 - Fix for running nested guests with in-kernel IRQ chip - Fix race condition causing occasional host hard lockup - Minor cleanups and bugfixes
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Paolo Bonzini authored
Merge branch 'x86-seves-for-paolo' of https://git.kernel.org/pub/scm/linux/kernel/git/tip/tip into HEAD
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Wang Wensheng authored
Build the kernel with `C=2`: arch/powerpc/kvm/book3s_hv_nested.c:572:25: warning: symbol 'kvmhv_alloc_nested' was not declared. Should it be static? arch/powerpc/kvm/book3s_64_mmu_radix.c:350:6: warning: symbol 'kvmppc_radix_set_pte_at' was not declared. Should it be static? arch/powerpc/kvm/book3s_hv.c:3568:5: warning: symbol 'kvmhv_p9_guest_entry' was not declared. Should it be static? arch/powerpc/kvm/book3s_hv_rm_xics.c:767:15: warning: symbol 'eoi_rc' was not declared. Should it be static? arch/powerpc/kvm/book3s_64_vio_hv.c:240:13: warning: symbol 'iommu_tce_kill_rm' was not declared. Should it be static? arch/powerpc/kvm/book3s_64_vio.c:492:6: warning: symbol 'kvmppc_tce_iommu_do_map' was not declared. Should it be static? arch/powerpc/kvm/book3s_pr.c:572:6: warning: symbol 'kvmppc_set_pvr_pr' was not declared. Should it be static? Those symbols are used only in the files that define them so make them static to fix the warnings. Signed-off-by:
Wang Wensheng <wangwensheng4@huawei.com> Signed-off-by:
Paul Mackerras <paulus@ozlabs.org>
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Jing Xiangfeng authored
The variable ret is being initialized with '-ENOMEM' that is meaningless. So remove it. Signed-off-by:
Jing Xiangfeng <jingxiangfeng@huawei.com> Reviewed-by:
Fabiano Rosas <farosas@linux.ibm.com> Signed-off-by:
Paul Mackerras <paulus@ozlabs.org>
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