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* KVM: X86: Narrow down the IPI fastpath to single target IPIWanpeng Li2020-03-261-1/+4
| | | | | | | | | | | | | | | | | | The original single target IPI fastpath patch forgot to filter the ICR destination shorthand field. Multicast IPI is not suitable for this feature since wakeup the multiple sleeping vCPUs will extend the interrupt disabled time, it especially worse in the over-subscribe and VM has a little bit more vCPUs scenario. Let's narrow it down to single target IPI. Two VMs, each is 76 vCPUs, one running 'ebizzy -M', the other running cyclictest on all vCPUs, w/ this patch, the avg score of cyclictest can improve more than 5%. (pv tlb, pv ipi, pv sched yield are disabled during testing to avoid the disturb). Signed-off-by: Wanpeng Li <wanpengli@tencent.com> Message-Id: <1585189202-1708-3-git-send-email-wanpengli@tencent.com> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
* KVM: LAPIC: Also cancel preemption timer when disarm LAPIC timerWanpeng Li2020-03-241-0/+6
| | | | | | | | | | | The timer is disarmed when switching between TSC deadline and other modes, we should set everything to disarmed state, however, LAPIC timer can be emulated by preemption timer, it still works if vmx->hv_deadline_timer is not -1. This patch also cancels preemption timer when disarm LAPIC timer. Signed-off-by: Wanpeng Li <wanpengli@tencent.com> Message-Id: <1585031530-19823-1-git-send-email-wanpengli@tencent.com> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
* KVM: VMX: don't allow memory operands for inline asm that modifies SPNick Desaulniers2020-03-231-1/+1
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | THUNK_TARGET defines [thunk_target] as having "rm" input constraints when CONFIG_RETPOLINE is not set, which isn't constrained enough for this specific case. For inline assembly that modifies the stack pointer before using this input, the underspecification of constraints is dangerous, and results in an indirect call to a previously pushed flags register. In this case `entry`'s stack slot is good enough to satisfy the "m" constraint in "rm", but the inline assembly in handle_external_interrupt_irqoff() modifies the stack pointer via push+pushf before using this input, which in this case results in calling what was the previous state of the flags register, rather than `entry`. Be more specific in the constraints by requiring `entry` be in a register, and not a memory operand. Reported-by: Dmitry Vyukov <dvyukov@google.com> Reported-by: syzbot+3f29ca2efb056a761e38@syzkaller.appspotmail.com Debugged-by: Alexander Potapenko <glider@google.com> Debugged-by: Paolo Bonzini <pbonzini@redhat.com> Debugged-by: Sean Christopherson <sean.j.christopherson@intel.com> Signed-off-by: Nick Desaulniers <ndesaulniers@google.com> Message-Id: <20200323191243.30002-1-ndesaulniers@google.com> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
* KVM: LAPIC: Mark hrtimer for period or oneshot mode to expire in hard ↵He Zhe2020-03-231-1/+1
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | interrupt context apic->lapic_timer.timer was initialized with HRTIMER_MODE_ABS_HARD but started later with HRTIMER_MODE_ABS, which may cause the following warning in PREEMPT_RT kernel. WARNING: CPU: 1 PID: 2957 at kernel/time/hrtimer.c:1129 hrtimer_start_range_ns+0x348/0x3f0 CPU: 1 PID: 2957 Comm: qemu-system-x86 Not tainted 5.4.23-rt11 #1 Hardware name: Supermicro SYS-E300-9A-8C/A2SDi-8C-HLN4F, BIOS 1.1a 09/18/2018 RIP: 0010:hrtimer_start_range_ns+0x348/0x3f0 Code: 4d b8 0f 94 c1 0f b6 c9 e8 35 f1 ff ff 4c 8b 45 b0 e9 3b fd ff ff e8 d7 3f fa ff 48 98 4c 03 34 c5 a0 26 bf 93 e9 a1 fd ff ff <0f> 0b e9 fd fc ff ff 65 8b 05 fa b7 90 6d 89 c0 48 0f a3 05 60 91 RSP: 0018:ffffbc60026ffaf8 EFLAGS: 00010202 RAX: 0000000000000001 RBX: ffff9d81657d4110 RCX: 0000000000000000 RDX: 0000000000000000 RSI: 0000006cc7987bcf RDI: ffff9d81657d4110 RBP: ffffbc60026ffb58 R08: 0000000000000001 R09: 0000000000000010 R10: 0000000000000000 R11: 0000000000000000 R12: 0000006cc7987bcf R13: 0000000000000000 R14: 0000006cc7987bcf R15: ffffbc60026d6a00 FS: 00007f401daed700(0000) GS:ffff9d81ffa40000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00000000ffffffff CR3: 0000000fa7574000 CR4: 00000000003426e0 Call Trace: ? kvm_release_pfn_clean+0x22/0x60 [kvm] start_sw_timer+0x85/0x230 [kvm] ? vmx_vmexit+0x1b/0x30 [kvm_intel] kvm_lapic_switch_to_sw_timer+0x72/0x80 [kvm] vmx_pre_block+0x1cb/0x260 [kvm_intel] ? vmx_vmexit+0xf/0x30 [kvm_intel] ? vmx_vmexit+0x1b/0x30 [kvm_intel] ? vmx_vmexit+0xf/0x30 [kvm_intel] ? vmx_vmexit+0x1b/0x30 [kvm_intel] ? vmx_vmexit+0xf/0x30 [kvm_intel] ? vmx_vmexit+0x1b/0x30 [kvm_intel] ? vmx_vmexit+0xf/0x30 [kvm_intel] ? vmx_vmexit+0xf/0x30 [kvm_intel] ? vmx_vmexit+0x1b/0x30 [kvm_intel] ? vmx_vmexit+0xf/0x30 [kvm_intel] ? vmx_vmexit+0x1b/0x30 [kvm_intel] ? vmx_vmexit+0xf/0x30 [kvm_intel] ? vmx_vmexit+0x1b/0x30 [kvm_intel] ? vmx_vmexit+0xf/0x30 [kvm_intel] ? vmx_vmexit+0x1b/0x30 [kvm_intel] ? vmx_vmexit+0xf/0x30 [kvm_intel] ? vmx_sync_pir_to_irr+0x9e/0x100 [kvm_intel] ? kvm_apic_has_interrupt+0x46/0x80 [kvm] kvm_arch_vcpu_ioctl_run+0x85b/0x1fa0 [kvm] ? _raw_spin_unlock_irqrestore+0x18/0x50 ? _copy_to_user+0x2c/0x30 kvm_vcpu_ioctl+0x235/0x660 [kvm] ? rt_spin_unlock+0x2c/0x50 do_vfs_ioctl+0x3e4/0x650 ? __fget+0x7a/0xa0 ksys_ioctl+0x67/0x90 __x64_sys_ioctl+0x1a/0x20 do_syscall_64+0x4d/0x120 entry_SYSCALL_64_after_hwframe+0x44/0xa9 RIP: 0033:0x7f4027cc54a7 Code: 00 00 90 48 8b 05 e9 59 0c 00 64 c7 00 26 00 00 00 48 c7 c0 ff ff ff ff c3 66 2e 0f 1f 84 00 00 00 00 00 b8 10 00 00 00 0f 05 <48> 3d 01 f0 ff ff 73 01 c3 48 8b 0d b9 59 0c 00 f7 d8 64 89 01 48 RSP: 002b:00007f401dae9858 EFLAGS: 00000246 ORIG_RAX: 0000000000000010 RAX: ffffffffffffffda RBX: 00005558bd029690 RCX: 00007f4027cc54a7 RDX: 0000000000000000 RSI: 000000000000ae80 RDI: 000000000000000d RBP: 00007f4028b72000 R08: 00005558bc829ad0 R09: 00000000ffffffff R10: 00005558bcf90ca0 R11: 0000000000000246 R12: 0000000000000000 R13: 0000000000000000 R14: 0000000000000000 R15: 00005558bce1c840 --[ end trace 0000000000000002 ]-- Signed-off-by: He Zhe <zhe.he@windriver.com> Message-Id: <1584687967-332859-1-git-send-email-zhe.he@windriver.com> Reviewed-by: Wanpeng Li <wanpengli@tencent.com> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
* KVM: SVM: Issue WBINVD after deactivating an SEV guestTom Lendacky2020-03-231-8/+14
| | | | | | | | | | | | | | | | | | | | | Currently, CLFLUSH is used to flush SEV guest memory before the guest is terminated (or a memory hotplug region is removed). However, CLFLUSH is not enough to ensure that SEV guest tagged data is flushed from the cache. With 33af3a7ef9e6 ("KVM: SVM: Reduce WBINVD/DF_FLUSH invocations"), the original WBINVD was removed. This then exposed crashes at random times because of a cache flush race with a page that had both a hypervisor and a guest tag in the cache. Restore the WBINVD when destroying an SEV guest and add a WBINVD to the svm_unregister_enc_region() function to ensure hotplug memory is flushed when removed. The DF_FLUSH can still be avoided at this point. Fixes: 33af3a7ef9e6 ("KVM: SVM: Reduce WBINVD/DF_FLUSH invocations") Signed-off-by: Tom Lendacky <thomas.lendacky@amd.com> Message-Id: <c8bf9087ca3711c5770bdeaafa3e45b717dc5ef4.1584720426.git.thomas.lendacky@amd.com> Cc: stable@vger.kernel.org Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
* KVM: SVM: document KVM_MEM_ENCRYPT_OP, let userspace detect if SEV is availablePaolo Bonzini2020-03-201-0/+3
| | | | | | | | | | | | Userspace has no way to query if SEV has been disabled with the sev module parameter of kvm-amd.ko. Actually it has one, but it is a hack: do ioctl(KVM_MEM_ENCRYPT_OP, NULL) and check if it returns EFAULT. Make it a little nicer by returning zero for SEV enabled and NULL argument, and while at it document the ioctl arguments. Cc: Brijesh Singh <brijesh.singh@amd.com> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
* KVM: x86: remove bogus user-triggerable WARN_ONPaolo Bonzini2020-03-201-1/+0
| | | | | | | | | | | | The WARN_ON is essentially comparing a user-provided value with 0. It is trivial to trigger it just by passing garbage to KVM_SET_CLOCK. Guests can break if you do so, but the same applies to every KVM_SET_* ioctl. So, if it hurts when you do like this, just do not do it. Reported-by: syzbot+00be5da1d75f1cc95f6b@syzkaller.appspotmail.com Fixes: 9446e6fce0ab ("KVM: x86: fix WARN_ON check of an unsigned less than zero") Cc: Sean Christopherson <sean.j.christopherson@intel.com> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
* Merge branch 'kvm-null-pointer-fix' into kvm-masterPaolo Bonzini2020-03-141-2/+3
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| * KVM: nVMX: avoid NULL pointer dereference with incorrect EVMCS GPAsVitaly Kuznetsov2020-03-141-2/+3
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | When an EVMCS enabled L1 guest on KVM will tries doing enlightened VMEnter with EVMCS GPA = 0 the host crashes because the evmcs_gpa != vmx->nested.hv_evmcs_vmptr condition in nested_vmx_handle_enlightened_vmptrld() will evaluate to false (as nested.hv_evmcs_vmptr is zeroed after init). The crash will happen on vmx->nested.hv_evmcs pointer dereference. Another problematic EVMCS ptr value is '-1' but it only causes host crash after nested_release_evmcs() invocation. The problem is exactly the same as with '0', we mistakenly think that the EVMCS pointer hasn't changed and thus nested.hv_evmcs_vmptr is valid. Resolve the issue by adding an additional !vmx->nested.hv_evmcs check to nested_vmx_handle_enlightened_vmptrld(), this way we will always be trying kvm_vcpu_map() when nested.hv_evmcs is NULL and this is supposed to catch all invalid EVMCS GPAs. Also, initialize hv_evmcs_vmptr to '0' in nested_release_evmcs() to be consistent with initialization where we don't currently set hv_evmcs_vmptr to '-1'. Cc: stable@vger.kernel.org Signed-off-by: Vitaly Kuznetsov <vkuznets@redhat.com> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
* | KVM: x86: Initializing all kvm_lapic_irq fields in ioapic_write_indirectNitesh Narayan Lal2020-03-141-2/+5
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Previously all fields of structure kvm_lapic_irq were not initialized before it was passed to kvm_bitmap_or_dest_vcpus(). Which will cause an issue when any of those fields are used for processing a request. For example not initializing the msi_redir_hint field before passing to the kvm_bitmap_or_dest_vcpus(), may lead to a misbehavior of kvm_apic_map_get_dest_lapic(). This will specifically happen when the kvm_lowest_prio_delivery() returns TRUE due to a non-zero garbage value of msi_redir_hint, which should not happen as the request belongs to APIC fixed delivery mode and we do not want to deliver the interrupt only to the lowest priority candidate. This patch initializes all the fields of kvm_lapic_irq based on the values of ioapic redirect_entry object before passing it on to kvm_bitmap_or_dest_vcpus(). Fixes: 7ee30bc132c6 ("KVM: x86: deliver KVM IOAPIC scan request to target vCPUs") Signed-off-by: Nitesh Narayan Lal <nitesh@redhat.com> Reviewed-by: Vitaly Kuznetsov <vkuznets@redhat.com> [Set level to false since the value doesn't really matter. Suggested by Vitaly Kuznetsov. - Paolo] Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
* | KVM: VMX: Condition ENCLS-exiting enabling on CPU support for SGX1Sean Christopherson2020-03-141-2/+14
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Enable ENCLS-exiting (and thus set vmcs.ENCLS_EXITING_BITMAP) only if the CPU supports SGX1. Per Intel's SDM, all ENCLS leafs #UD if SGX1 is not supported[*], i.e. intercepting ENCLS to inject a #UD is unnecessary. Avoiding ENCLS-exiting even when it is reported as supported by the CPU works around a reported issue where SGX is "hard" disabled after an S3 suspend/resume cycle, i.e. CPUID.0x7.SGX=0 and the VMCS field/control are enumerated as unsupported. While the root cause of the S3 issue is unknown, it's definitely _not_ a KVM (or kernel) bug, i.e. this is a workaround for what is most likely a hardware or firmware issue. As a bonus side effect, KVM saves a VMWRITE when first preparing vmcs01 and vmcs02. Note, SGX must be disabled in BIOS to take advantage of this workaround [*] The additional ENCLS CPUID check on SGX1 exists so that SGX can be globally "soft" disabled post-reset, e.g. if #MC bits in MCi_CTL are cleared. Soft disabled meaning disabling SGX without clearing the primary CPUID bit (in leaf 0x7) and without poking into non-SGX CPU paths, e.g. for the VMCS controls. Fixes: 0b665d304028 ("KVM: vmx: Inject #UD for SGX ENCLS instruction in guest") Reported-by: Toni Spets <toni.spets@iki.fi> Signed-off-by: Sean Christopherson <sean.j.christopherson@intel.com> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
* | KVM: fix Kconfig menu text for -WerrorJason A. Donenfeld2020-03-051-1/+1
| | | | | | | | | | | | | | | | | | This was evidently copy and pasted from the i915 driver, but the text wasn't updated. Fixes: 4f337faf1c55 ("KVM: allow disabling -Werror") Signed-off-by: Jason A. Donenfeld <Jason@zx2c4.com> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
* | KVM: x86: clear stale x86_emulate_ctxt->intercept valueVitaly Kuznetsov2020-03-031-0/+1
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | After commit 07721feee46b ("KVM: nVMX: Don't emulate instructions in guest mode") Hyper-V guests on KVM stopped booting with: kvm_nested_vmexit: rip fffff802987d6169 reason EPT_VIOLATION info1 181 info2 0 int_info 0 int_info_err 0 kvm_page_fault: address febd0000 error_code 181 kvm_emulate_insn: 0:fffff802987d6169: f3 a5 kvm_emulate_insn: 0:fffff802987d6169: f3 a5 FAIL kvm_inj_exception: #UD (0x0) "f3 a5" is a "rep movsw" instruction, which should not be intercepted at all. Commit c44b4c6ab80e ("KVM: emulate: clean up initializations in init_decode_cache") reduced the number of fields cleared by init_decode_cache() claiming that they are being cleared elsewhere, 'intercept', however, is left uncleared if the instruction does not have any of the "slow path" flags (NotImpl, Stack, Op3264, Sse, Mmx, CheckPerm, NearBranch, No16 and of course Intercept itself). Fixes: c44b4c6ab80e ("KVM: emulate: clean up initializations in init_decode_cache") Fixes: 07721feee46b ("KVM: nVMX: Don't emulate instructions in guest mode") Cc: stable@vger.kernel.org Suggested-by: Paolo Bonzini <pbonzini@redhat.com> Signed-off-by: Vitaly Kuznetsov <vkuznets@redhat.com> Reviewed-by: Sean Christopherson <sean.j.christopherson@intel.com> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
* | KVM: SVM: Fix the svm vmexit code for WRMSRHaiwei Li2020-03-021-1/+2
| | | | | | | | | | | | | | | | | | | | | | | | | | | | In svm, exit_code for MSR writes is not EXIT_REASON_MSR_WRITE which belongs to vmx. According to amd manual, SVM_EXIT_MSR(7ch) is the exit_code of VMEXIT_MSR due to RDMSR or WRMSR access to protected MSR. Additionally, the processor indicates in the VMCB's EXITINFO1 whether a RDMSR(EXITINFO1=0) or WRMSR(EXITINFO1=1) was intercepted. Signed-off-by: Haiwei Li <lihaiwei@tencent.com> Fixes: 1e9e2622a149 ("KVM: VMX: FIXED+PHYSICAL mode single target IPI fastpath", 2019-11-21) Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
* | KVM: X86: Fix dereference null cpufreq policyWanpeng Li2020-03-021-3/+5
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Naresh Kamboju reported: Linux version 5.6.0-rc4 (oe-user@oe-host) (gcc version (GCC)) #1 SMP Sun Mar 1 22:59:08 UTC 2020 kvm: no hardware support BUG: kernel NULL pointer dereference, address: 000000000000028c #PF: supervisor read access in kernel mode #PF: error_code(0x0000) - not-present page PGD 0 P4D 0 Oops: 0000 [#1] SMP NOPTI CPU: 0 PID: 1 Comm: swapper/0 Not tainted 5.6.0-rc4 #1 Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), 04/01/2014 RIP: 0010:kobject_put+0x12/0x1c0 Call Trace: cpufreq_cpu_put+0x15/0x20 kvm_arch_init+0x1f6/0x2b0 kvm_init+0x31/0x290 ? svm_check_processor_compat+0xd/0xd ? svm_check_processor_compat+0xd/0xd svm_init+0x21/0x23 do_one_initcall+0x61/0x2f0 ? rdinit_setup+0x30/0x30 ? rcu_read_lock_sched_held+0x4f/0x80 kernel_init_freeable+0x219/0x279 ? rest_init+0x250/0x250 kernel_init+0xe/0x110 ret_from_fork+0x27/0x50 Modules linked in: CR2: 000000000000028c ---[ end trace 239abf40c55c409b ]--- RIP: 0010:kobject_put+0x12/0x1c0 cpufreq policy which is get by cpufreq_cpu_get() can be NULL if it is failure, this patch takes care of it. Fixes: aaec7c03de (KVM: x86: avoid useless copy of cpufreq policy) Reported-by: Naresh Kamboju <naresh.kamboju@linaro.org> Cc: Naresh Kamboju <naresh.kamboju@linaro.org> Signed-off-by: Wanpeng Li <wanpengli@tencent.com> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
* | KVM: VMX: check descriptor table exits on instruction emulationOliver Upton2020-03-011-0/+15
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | KVM emulates UMIP on hardware that doesn't support it by setting the 'descriptor table exiting' VM-execution control and performing instruction emulation. When running nested, this emulation is broken as KVM refuses to emulate L2 instructions by default. Correct this regression by allowing the emulation of descriptor table instructions if L1 hasn't requested 'descriptor table exiting'. Fixes: 07721feee46b ("KVM: nVMX: Don't emulate instructions in guest mode") Reported-by: Jan Kiszka <jan.kiszka@web.de> Cc: stable@vger.kernel.org Cc: Paolo Bonzini <pbonzini@redhat.com> Cc: Jim Mattson <jmattson@google.com> Signed-off-by: Oliver Upton <oupton@google.com> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
* | kvm: x86: Limit the number of "kvm: disabled by bios" messagesErwan Velu2020-02-281-2/+2
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | In older version of systemd(219), at boot time, udevadm is called with : /usr/bin/udevadm trigger --type=devices --action=add" This program generates an echo "add" in /sys/devices/system/cpu/cpu<x>/uevent, leading to the "kvm: disabled by bios" message in case of your Bios disabled the virtualization extensions. On a modern system running up to 256 CPU threads, this pollutes the Kernel logs. This patch offers to ratelimit this message to avoid any userspace program triggering this uevent printing this message too often. This patch is only a workaround but greatly reduce the pollution without breaking the current behavior of printing a message if some try to instantiate KVM on a system that doesn't support it. Note that recent versions of systemd (>239) do not have trigger this behavior. This patch will be useful at least for some using older systemd with recent Kernels. Signed-off-by: Erwan Velu <e.velu@criteo.com> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
* | KVM: x86: avoid useless copy of cpufreq policyPaolo Bonzini2020-02-281-5/+5
| | | | | | | | | | | | | | | | | | struct cpufreq_policy is quite big and it is not a good idea to allocate one on the stack. Just use cpufreq_cpu_get and cpufreq_cpu_put which is even simpler. Reported-by: Christoph Hellwig <hch@lst.de> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
* | KVM: allow disabling -WerrorPaolo Bonzini2020-02-282-1/+14
| | | | | | | | | | | | | | | | Restrict -Werror to well-tested configurations and allow disabling it via Kconfig. Reported-by: Christoph Hellwig <hch@lst.de> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
* | KVM: x86: allow compiling as non-module with W=1Valdis Klētnieks2020-02-282-0/+4
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Compile error with CONFIG_KVM_INTEL=y and W=1: CC arch/x86/kvm/vmx/vmx.o arch/x86/kvm/vmx/vmx.c:68:32: error: 'vmx_cpu_id' defined but not used [-Werror=unused-const-variable=] 68 | static const struct x86_cpu_id vmx_cpu_id[] = { | ^~~~~~~~~~ cc1: all warnings being treated as errors When building with =y, the MODULE_DEVICE_TABLE macro doesn't generate a reference to the structure (or any code at all). This makes W=1 compiles unhappy. Wrap both in a #ifdef to avoid the issue. Signed-off-by: Valdis Kletnieks <valdis.kletnieks@vt.edu> [Do the same for CONFIG_KVM_AMD. - Paolo] Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
* | KVM: SVM: allocate AVIC data structures based on kvm_amd module parameterPaolo Bonzini2020-02-281-1/+2
|/ | | | | | | | | | | | | Even if APICv is disabled at startup, the backing page and ir_list need to be initialized in case they are needed later. The only case in which this can be skipped is for userspace irqchip, and that must be done because avic_init_backing_page dereferences vcpu->arch.apic (which is NULL for userspace irqchip). Tested-by: rmuncrief@humanavance.com Fixes: https://bugzilla.kernel.org/show_bug.cgi?id=206579 Reviewed-by: Miaohe Lin <linmiaohe@huawei.com> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
* KVM: nVMX: Check IO instruction VM-exit conditionsOliver Upton2020-02-232-7/+52
| | | | | | | | | | Consult the 'unconditional IO exiting' and 'use IO bitmaps' VM-execution controls when checking instruction interception. If the 'use IO bitmaps' VM-execution control is 1, check the instruction access against the IO bitmaps to determine if the instruction causes a VM-exit. Signed-off-by: Oliver Upton <oupton@google.com> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
* KVM: nVMX: Refactor IO bitmap checks into helper functionOliver Upton2020-02-232-14/+27
| | | | | | | | | | Checks against the IO bitmap are useful for both instruction emulation and VM-exit reflection. Refactor the IO bitmap checks into a helper function. Signed-off-by: Oliver Upton <oupton@google.com> Reviewed-by: Vitaly Kuznetsov <vkuznets@redhat.com> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
* KVM: nVMX: Don't emulate instructions in guest modePaolo Bonzini2020-02-231-1/+1
| | | | | | | | | | | vmx_check_intercept is not yet fully implemented. To avoid emulating instructions disallowed by the L1 hypervisor, refuse to emulate instructions by default. Cc: stable@vger.kernel.org [Made commit, added commit msg - Oliver] Signed-off-by: Oliver Upton <oupton@google.com> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
* KVM: nVMX: Emulate MTF when performing instruction emulationOliver Upton2020-02-236-2/+81
| | | | | | | | | | | | | | | | | Since commit 5f3d45e7f282 ("kvm/x86: add support for MONITOR_TRAP_FLAG"), KVM has allowed an L1 guest to use the monitor trap flag processor-based execution control for its L2 guest. KVM simply forwards any MTF VM-exits to the L1 guest, which works for normal instruction execution. However, when KVM needs to emulate an instruction on the behalf of an L2 guest, the monitor trap flag is not emulated. Add the necessary logic to kvm_skip_emulated_instruction() to synthesize an MTF VM-exit to L1 upon instruction emulation for L2. Fixes: 5f3d45e7f282 ("kvm/x86: add support for MONITOR_TRAP_FLAG") Signed-off-by: Oliver Upton <oupton@google.com> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
* KVM: fix error handling in svm_hardware_setupLi RongQing2020-02-231-21/+20
| | | | | | | | | | | | | | rename svm_hardware_unsetup as svm_hardware_teardown, move it before svm_hardware_setup, and call it to free all memory if fail to setup in svm_hardware_setup, otherwise memory will be leaked remove __exit attribute for it since it is called in __init function Signed-off-by: Li RongQing <lirongqing@baidu.com> Reviewed-by: Vitaly Kuznetsov <vkuznets@redhat.com> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
* KVM: SVM: Fix potential memory leak in svm_cpu_init()Miaohe Lin2020-02-211-7/+6
| | | | | | | | | | | When kmalloc memory for sd->sev_vmcbs failed, we forget to free the page held by sd->save_area. Also get rid of the var r as '-ENOMEM' is actually the only possible outcome here. Reviewed-by: Liran Alon <liran.alon@oracle.com> Reviewed-by: Vitaly Kuznetsov <vkuznets@redhat.com> Signed-off-by: Miaohe Lin <linmiaohe@huawei.com> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
* KVM: apic: avoid calculating pending eoi from an uninitialized valMiaohe Lin2020-02-211-1/+3
| | | | | | | | | | | When pv_eoi_get_user() fails, 'val' may remain uninitialized and the return value of pv_eoi_get_pending() becomes random. Fix the issue by initializing the variable. Reviewed-by: Vitaly Kuznetsov <vkuznets@redhat.com> Signed-off-by: Miaohe Lin <linmiaohe@huawei.com> Cc: stable@vger.kernel.org Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
* KVM: nVMX: clear PIN_BASED_POSTED_INTR from nested pinbased_ctls only when ↵Vitaly Kuznetsov2020-02-214-11/+8
| | | | | | | | | | | | | | | | | | | | | | | | | | apicv is globally disabled When apicv is disabled on a vCPU (e.g. by enabling KVM_CAP_HYPERV_SYNIC*), nothing happens to VMX MSRs on the already existing vCPUs, however, all new ones are created with PIN_BASED_POSTED_INTR filtered out. This is very confusing and results in the following picture inside the guest: $ rdmsr -ax 0x48d ff00000016 7f00000016 7f00000016 7f00000016 This is observed with QEMU and 4-vCPU guest: QEMU creates vCPU0, does KVM_CAP_HYPERV_SYNIC2 and then creates the remaining three. L1 hypervisor may only check CPU0's controls to find out what features are available and it will be very confused later. Switch to setting PIN_BASED_POSTED_INTR control based on global 'enable_apicv' setting. Signed-off-by: Vitaly Kuznetsov <vkuznets@redhat.com> Cc: stable@vger.kernel.org Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
* KVM: nVMX: handle nested posted interrupts when apicv is disabled for L1Vitaly Kuznetsov2020-02-213-9/+16
| | | | | | | | | | | | Even when APICv is disabled for L1 it can (and, actually, is) still available for L2, this means we need to always call vmx_deliver_nested_posted_interrupt() when attempting an interrupt delivery. Suggested-by: Paolo Bonzini <pbonzini@redhat.com> Signed-off-by: Vitaly Kuznetsov <vkuznets@redhat.com> Cc: stable@vger.kernel.org Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
* kvm: x86: svm: Fix NULL pointer dereference when AVIC not enabledSuravee Suthikulpanit2020-02-211-0/+3
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Launching VM w/ AVIC disabled together with pass-through device results in NULL pointer dereference bug with the following call trace. RIP: 0010:svm_refresh_apicv_exec_ctrl+0x17e/0x1a0 [kvm_amd] Call Trace: kvm_vcpu_update_apicv+0x44/0x60 [kvm] kvm_arch_vcpu_ioctl_run+0x3f4/0x1c80 [kvm] kvm_vcpu_ioctl+0x3d8/0x650 [kvm] do_vfs_ioctl+0xaa/0x660 ? tomoyo_file_ioctl+0x19/0x20 ksys_ioctl+0x67/0x90 __x64_sys_ioctl+0x1a/0x20 do_syscall_64+0x57/0x190 entry_SYSCALL_64_after_hwframe+0x44/0xa9 Investigation shows that this is due to the uninitialized usage of struct vapu_svm.ir_list in the svm_set_pi_irte_mode(), which is called from svm_refresh_apicv_exec_ctrl(). The ir_list is initialized only if AVIC is enabled. So, fixes by adding a check if AVIC is enabled in the svm_refresh_apicv_exec_ctrl(). Bugzilla: https://bugzilla.kernel.org/show_bug.cgi?id=206579 Fixes: 8937d762396d ("kvm: x86: svm: Add support to (de)activate posted interrupts.") Signed-off-by: Suravee Suthikulpanit <suravee.suthikulpanit@amd.com> Tested-by: Alex Williamson <alex.williamson@redhat.com> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
* KVM: nVMX: Hold KVM's srcu lock when syncing vmcs12->shadowwanpeng li2020-02-211-2/+9
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | For the duration of mapping eVMCS, it derefences ->memslots without holding ->srcu or ->slots_lock when accessing hv assist page. This patch fixes it by moving nested_sync_vmcs12_to_shadow to prepare_guest_switch, where the SRCU is already taken. It can be reproduced by running kvm's evmcs_test selftest. ============================= warning: suspicious rcu usage 5.6.0-rc1+ #53 tainted: g w ioe ----------------------------- ./include/linux/kvm_host.h:623 suspicious rcu_dereference_check() usage! other info that might help us debug this: rcu_scheduler_active = 2, debug_locks = 1 1 lock held by evmcs_test/8507: #0: ffff9ddd156d00d0 (&vcpu->mutex){+.+.}, at: kvm_vcpu_ioctl+0x85/0x680 [kvm] stack backtrace: cpu: 6 pid: 8507 comm: evmcs_test tainted: g w ioe 5.6.0-rc1+ #53 hardware name: dell inc. optiplex 7040/0jctf8, bios 1.4.9 09/12/2016 call trace: dump_stack+0x68/0x9b kvm_read_guest_cached+0x11d/0x150 [kvm] kvm_hv_get_assist_page+0x33/0x40 [kvm] nested_enlightened_vmentry+0x2c/0x60 [kvm_intel] nested_vmx_handle_enlightened_vmptrld.part.52+0x32/0x1c0 [kvm_intel] nested_sync_vmcs12_to_shadow+0x439/0x680 [kvm_intel] vmx_vcpu_run+0x67a/0xe60 [kvm_intel] vcpu_enter_guest+0x35e/0x1bc0 [kvm] kvm_arch_vcpu_ioctl_run+0x40b/0x670 [kvm] kvm_vcpu_ioctl+0x370/0x680 [kvm] ksys_ioctl+0x235/0x850 __x64_sys_ioctl+0x16/0x20 do_syscall_64+0x77/0x780 entry_syscall_64_after_hwframe+0x49/0xbe Signed-off-by: Wanpeng Li <wanpengli@tencent.com> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
* KVM: x86: don't notify userspace IOAPIC on edge-triggered interrupt EOIMiaohe Lin2020-02-211-1/+1
| | | | | | | | | | | | | | | Commit 13db77347db1 ("KVM: x86: don't notify userspace IOAPIC on edge EOI") said, edge-triggered interrupts don't set a bit in TMR, which means that IOAPIC isn't notified on EOI. And var level indicates level-triggered interrupt. But commit 3159d36ad799 ("KVM: x86: use generic function for MSI parsing") replace var level with irq.level by mistake. Fix it by changing irq.level to irq.trig_mode. Cc: stable@vger.kernel.org Fixes: 3159d36ad799 ("KVM: x86: use generic function for MSI parsing") Signed-off-by: Miaohe Lin <linmiaohe@huawei.com> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
* kvm/emulate: fix a -Werror=cast-function-typeQian Cai2020-02-201-22/+14
| | | | | | | | | | | | | | | | arch/x86/kvm/emulate.c: In function 'x86_emulate_insn': arch/x86/kvm/emulate.c:5686:22: error: cast between incompatible function types from 'int (*)(struct x86_emulate_ctxt *)' to 'void (*)(struct fastop *)' [-Werror=cast-function-type] rc = fastop(ctxt, (fastop_t)ctxt->execute); Fix it by using an unnamed union of a (*execute) function pointer and a (*fastop) function pointer. Fixes: 3009afc6e39e ("KVM: x86: Use a typedef for fastop functions") Suggested-by: Paolo Bonzini <pbonzini@redhat.com> Signed-off-by: Qian Cai <cai@lca.pw> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
* KVM: x86: fix incorrect comparison in trace eventPaolo Bonzini2020-02-201-1/+1
| | | | | | | The "u" field in the event has three states, -1/0/1. Using u8 however means that comparison with -1 will always fail, so change to signed char. Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
* KVM: nVMX: Fix some obsolete comments and grammar errorMiaohe Lin2020-02-171-5/+5
| | | | | | | Fix wrong variable names and grammar error in comment. Signed-off-by: Miaohe Lin <linmiaohe@huawei.com> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
* KVM: x86: enable -WerrorPaolo Bonzini2020-02-121-0/+1
| | | | | | | Avoid more embarrassing mistakes. At least those that the compiler can catch. Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
* KVM: x86: fix WARN_ON check of an unsigned less than zeroPaolo Bonzini2020-02-121-1/+1
| | | | | | | | | | | | | The check cpu->hv_clock.system_time < 0 is redundant since system_time is a u64 and hence can never be less than zero. But what was actually meant is to check that the result is positive, since kernel_ns and v->kvm->arch.kvmclock_offset are both s64. Reported-by: Colin King <colin.king@canonical.com> Suggested-by: Sean Christopherson <sean.j.christopherson@intel.com> Addresses-Coverity: ("Macro compares unsigned to 0") Reviewed-by: Miaohe Lin <linmiaohe@huawei.com> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
* KVM: x86/mmu: Fix struct guest_walker arrays for 5-level pagingSean Christopherson2020-02-121-1/+1
| | | | | | | | | | | | | | | | | | | Define PT_MAX_FULL_LEVELS as PT64_ROOT_MAX_LEVEL, i.e. 5, to fix shadow paging for 5-level guest page tables. PT_MAX_FULL_LEVELS is used to size the arrays that track guest pages table information, i.e. using a "max levels" of 4 causes KVM to access garbage beyond the end of an array when querying state for level 5 entries. E.g. FNAME(gpte_changed) will read garbage and most likely return %true for a level 5 entry, soft-hanging the guest because FNAME(fetch) will restart the guest instead of creating SPTEs because it thinks the guest PTE has changed. Note, KVM doesn't yet support 5-level nested EPT, so PT_MAX_FULL_LEVELS gets to stay "4" for the PTTYPE_EPT case. Fixes: 855feb673640 ("KVM: MMU: Add 5 level EPT & Shadow page table support.") Cc: stable@vger.kernel.org Signed-off-by: Sean Christopherson <sean.j.christopherson@intel.com> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
* KVM: nVMX: Use correct root level for nested EPT shadow page tablesSean Christopherson2020-02-121-0/+3
| | | | | | | | | | | | | Hardcode the EPT page-walk level for L2 to be 4 levels, as KVM's MMU currently also hardcodes the page walk level for nested EPT to be 4 levels. The L2 guest is all but guaranteed to soft hang on its first instruction when L1 is using EPT, as KVM will construct 4-level page tables and then tell hardware to use 5-level page tables. Fixes: 855feb673640 ("KVM: MMU: Add 5 level EPT & Shadow page table support.") Cc: stable@vger.kernel.org Signed-off-by: Sean Christopherson <sean.j.christopherson@intel.com> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
* KVM: nVMX: Fix some comment typos and coding styleMiaohe Lin2020-02-121-2/+3
| | | | | | | | | Fix some typos in the comments. Also fix coding style. [Sean Christopherson rewrites the comment of write_fault_to_shadow_pgtable field in struct kvm_vcpu_arch.] Signed-off-by: Miaohe Lin <linmiaohe@huawei.com> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
* KVM: x86/mmu: Avoid retpoline on ->page_fault() with TDPSean Christopherson2020-02-123-7/+19
| | | | | | | | | | | | | | Wrap calls to ->page_fault() with a small shim to directly invoke the TDP fault handler when the kernel is using retpolines and TDP is being used. Single out the TDP fault handler and annotate the TDP path as likely to coerce the compiler into preferring it over the indirect function call. Rename tdp_page_fault() to kvm_tdp_page_fault(), as it's exposed outside of mmu.c to allow inlining the shim. Signed-off-by: Sean Christopherson <sean.j.christopherson@intel.com> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
* KVM: apic: reuse smp_wmb() in kvm_make_request()Miaohe Lin2020-02-121-3/+0
| | | | | | | | | | kvm_make_request() provides smp_wmb() so pending_events changes are guaranteed to be visible. Signed-off-by: Miaohe Lin <linmiaohe@huawei.com> Reviewed-by: Vitaly Kuznetsov <vkuznets@redhat.com> Reviewed-by: Sean Christopherson <sean.j.christopherson@intel.com> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
* KVM: x86: remove duplicated KVM_REQ_EVENT requestMiaohe Lin2020-02-121-1/+0
| | | | | | | | | The KVM_REQ_EVENT request is already made in kvm_set_rflags(). We should not make it again. Signed-off-by: Miaohe Lin <linmiaohe@huawei.com> Reviewed-by: Vitaly Kuznetsov <vkuznets@redhat.com> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
* KVM: x86: Deliver exception payload on KVM_GET_VCPU_EVENTSOliver Upton2020-02-121-13/+16
| | | | | | | | | | | | | | | | | | | | | KVM allows the deferral of exception payloads when a vCPU is in guest mode to allow the L1 hypervisor to intercept certain events (#PF, #DB) before register state has been modified. However, this behavior is incompatible with the KVM_{GET,SET}_VCPU_EVENTS ABI, as userspace expects register state to have been immediately modified. Userspace may opt-in for the payload deferral behavior with the KVM_CAP_EXCEPTION_PAYLOAD per-VM capability. As such, kvm_multiple_exception() will immediately manipulate guest registers if the capability hasn't been requested. Since the deferral is only necessary if a userspace ioctl were to be serviced at the same as a payload bearing exception is recognized, this behavior can be relaxed. Instead, opportunistically defer the payload from kvm_multiple_exception() and deliver the payload before completing a KVM_GET_VCPU_EVENTS ioctl. Signed-off-by: Oliver Upton <oupton@google.com> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
* KVM: nVMX: Handle pending #DB when injecting INIT VM-exitOliver Upton2020-02-121-0/+28
| | | | | | | | | | | SDM 27.3.4 states that the 'pending debug exceptions' VMCS field will be populated if a VM-exit caused by an INIT signal takes priority over a debug-trap. Emulate this behavior when synthesizing an INIT signal VM-exit into L1. Fixes: 4b9852f4f389 ("KVM: x86: Fix INIT signal handling in various CPU states") Signed-off-by: Oliver Upton <oupton@google.com> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
* KVM: x86: Mask off reserved bit from #DB exception payloadOliver Upton2020-02-121-0/+8
| | | | | | | | | | | KVM defines the #DB payload as compatible with the 'pending debug exceptions' field under VMX, not DR6. Mask off bit 12 when applying the payload to DR6, as it is reserved on DR6 but not the 'pending debug exceptions' field. Fixes: f10c729ff965 ("kvm: vmx: Defer setting of DR6 until #DB delivery") Signed-off-by: Oliver Upton <oupton@google.com> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
* KVM: x86: do not reset microcode version on INIT or RESETPaolo Bonzini2020-02-122-2/+2
| | | | | | | | | | | | | | | | | Do not initialize the microcode version at RESET or INIT, only on vCPU creation. Microcode updates are not lost during INIT, and exact behavior across a warm RESET is not specified by the architecture. Since we do not support a microcode update directly from the hypervisor, but only as a result of userspace setting the microcode version MSR, it's simpler for userspace if we do nothing in KVM and let userspace emulate behavior for RESET as it sees fit. Userspace can tie the fix to the availability of MSR_IA32_UCODE_REV in the list of emulated MSRs. Reported-by: Alex Williamson <alex.williamson@redhat.com> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
* KVM: vmx: delete meaningless vmx_decache_cr0_guest_bits() declarationMiaohe Lin2020-02-051-2/+0
| | | | | | | | The function vmx_decache_cr0_guest_bits() is only called below its implementation. So this is meaningless and should be removed. Signed-off-by: Miaohe Lin <linmiaohe@huawei.com> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
* KVM: x86: Mark CR4.UMIP as reserved based on associated CPUID bitSean Christopherson2020-02-051-0/+2
| | | | | | | | | | | | | | | | | Re-add code to mark CR4.UMIP as reserved if UMIP is not supported by the host. The UMIP handling was unintentionally dropped during a recent refactoring. Not flagging CR4.UMIP allows the guest to set its CR4.UMIP regardless of host support or userspace desires. On CPUs with UMIP support, including emulated UMIP, this allows the guest to enable UMIP against the wishes of the userspace VMM. On CPUs without any form of UMIP, this results in a failed VM-Enter due to invalid guest state. Fixes: 345599f9a2928 ("KVM: x86: Add macro to ensure reserved cr4 bits checks stay in sync") Signed-off-by: Sean Christopherson <sean.j.christopherson@intel.com> Reviewed-by: Vitaly Kuznetsov <vkuznets@redhat.com> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
generated by cgit v1.2.3 (git 2.25.1) at 2024-10-19 19:50:31 +0000