- 30 Apr, 2019 7 commits
-
-
Jim Mattson authored
The size checks in vmx_nested_state are wrong because the calculations are made based on the size of a pointer to a struct kvm_nested_state rather than the size of a struct kvm_nested_state. Reported-by:
Felix Wilhelm <fwilhelm@google.com> Signed-off-by:
Jim Mattson <jmattson@google.com> Reviewed-by:
Drew Schmitt <dasch@google.com> Reviewed-by:
Marc Orr <marcorr@google.com> Reviewed-by:
Peter Shier <pshier@google.com> Reviewed-by:
Krish Sadhukhan <krish.sadhukhan@oracle.com> Fixes: 8fcc4b59 Cc: stable@ver.kernel.org Signed-off-by:
Paolo Bonzini <pbonzini@redhat.com>
-
Paolo Bonzini authored
Merge tag 'kvmarm-fixes-for-5.1-2' of git://git.kernel.org/pub/scm/linux/kernel/git/kvmarm/kvmarm into kvm-master KVM/ARM fixes for 5.1, take #2: - Don't try to emulate timers on userspace access - Fix unaligned huge mappings, again - Properly reset a vcpu that fails to reset(!) - Properly retire pending LPIs on reset - Fix computation of emulated CNTP_TVAL
-
Vitaly Kuznetsov authored
Enlightened VMCS is only supported on Intel CPUs but the test shouldn't fail completely. Signed-off-by:
Vitaly Kuznetsov <vkuznets@redhat.com> Signed-off-by:
-
Sean Christopherson authored
...to avoid dereferencing a null pointer when querying the per-vCPU timer advance. Fixes: 39497d76 ("KVM: lapic: Track lapic timer advance per vCPU") Reported-by: syzbot+f7e65445a40d3e0e4ebf@syzkaller.appspotmail.com Signed-off-by:
Sean Christopherson <sean.j.christopherson@intel.com> Reviewed-by:
Konrad Rzeszutek Wilk <konrad.wilk@oracle.com> Signed-off-by:
-
Paolo Bonzini authored
If a memory slot's size is not a multiple of 64 pages (256K), then the KVM_CLEAR_DIRTY_LOG API is unusable: clearing the final 64 pages either requires the requested page range to go beyond memslot->npages, or requires log->num_pages to be unaligned, and kvm_clear_dirty_log_protect requires log->num_pages to be both in range and aligned. To allow this case, allow log->num_pages not to be a multiple of 64 if it ends exactly on the last page of the slot. Reported-by:
Peter Xu <peterx@redhat.com> Fixes: 98938aa8 ("KVM: validate userspace input in kvm_clear_dirty_log_protect()", 2019-01-02) Signed-off-by:
-
Vitaly Kuznetsov authored
Commit 47c42e6b ("KVM: x86: fix handling of role.cr4_pae and rename it to 'gpte_size'") introduced a regression: 32-bit PAE guests stopped working. The issue appears to be: when guest switches (enables) PAE we need to re-initialize MMU context (set context->root_level, do reset_rsvds_bits_mask(), ...) but init_kvm_tdp_mmu() doesn't do that because we threw away is_pae(vcpu) flag from mmu role. Restore it to kvm_mmu_extended_role (as we now don't need it in base role) to fix the issue. Fixes: 47c42e6b ("KVM: x86: fix handling of role.cr4_pae and rename it to 'gpte_size'") Signed-off-by:
-
Sean Christopherson authored
KVM's recent bug fix to update %rip after emulating I/O broke userspace that relied on the previous behavior of incrementing %rip prior to exiting to userspace. When running a Windows XP guest on AMD hardware, Qemu may patch "OUT 0x7E" instructions in reaction to the OUT itself. Because KVM's old behavior was to increment %rip before exiting to userspace to handle the I/O, Qemu manually adjusted %rip to account for the OUT instruction. Arguably this is a userspace bug as KVM requires userspace to re-enter the kernel to complete instruction emulation before taking any other actions. That being said, this is a bit of a grey area and breaking userspace that has worked for many years is bad. Pre-increment %rip on OUT to port 0x7e before exiting to userspace to hack around the issue. Fixes: 45def77e ("KVM: x86: update %rip after emulating IO") Reported-by:
Simon Becherer <simon@becherer.de> Reported-and-tested-by:
Iakov Karpov <srid@rkmail.ru> Reported-by:
Gabriele Balducci <balducci@units.it> Reported-by:
Antti Antinoja <reader@fennosys.fi> Cc: stable@vger.kernel.org Cc: Takashi Iwai <tiwai@suse.com> Cc: Jiri Slaby <jslaby@suse.com> Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Signed-off-by:
-
- 29 Apr, 2019 1 commit
-
-
Andrew Jones authored
KVM_GET_DIRTY_LOG is implemented by all architectures, not just x86, and KVM_CAP_MANUAL_DIRTY_LOG_PROTECT is additionally implemented by arm, arm64, and mips. Signed-off-by:
Andrew Jones <drjones@redhat.com> Signed-off-by:
-
- 27 Apr, 2019 1 commit
-
-
Rick Edgecombe authored
The not-so-recent change to move VMX's VM-Exit handing to a dedicated "function" unintentionally exposed KVM to a speculative attack from the guest by executing a RET prior to stuffing the RSB. Make RSB stuffing happen immediately after VM-Exit, before any unpaired returns. Alternatively, the VM-Exit path could postpone full RSB stuffing until its current location by stuffing the RSB only as needed, or by avoiding returns in the VM-Exit path entirely, but both alternatives are beyond ugly since vmx_vmexit() has multiple indirect callers (by way of vmx_vmenter()). And putting the RSB stuffing immediately after VM-Exit makes it much less likely to be re-broken in the future. Note, the cost of PUSH/POP could be avoided in the normal flow by pairing the PUSH RAX with the POP RAX in __vmx_vcpu_run() and adding an a POP to nested_vmx_check_vmentry_hw(), but such a weird/subtle dependency is likely to cause problems in the long run, and PUSH/POP will take all of a few cycles, which is peanuts compared to the number of cycles required to fill the RSB. Fixes: 453eafbe ("KVM: VMX: Move VM-Enter + VM-Exit handling to non-inline sub-routines") Reported-by:
Rick Edgecombe <rick.p.edgecombe@intel.com> Signed-off-by:
-
- 25 Apr, 2019 3 commits
-
-
Christoffer Dall authored
When a VCPU never runs before a guest exists, but we set timer registers up via ioctls, the associated hrtimer might never get cancelled. Since we moved vcpu_load/put into the arch-specific implementations and only have load/put for KVM_RUN, we won't ever have a scheduled hrtimer for emulating a timer when modifying the timer state via an ioctl from user space. All we need to do is make sure that we pick up the right state when we load the timer state next time userspace calls KVM_RUN again. We also do not need to worry about this interacting with the bg_timer, because if we were in WFI from the guest, and somehow ended up in a kvm_arm_timer_set_reg, it means that: 1. the VCPU thread has received a signal, 2. we have called vcpu_load when being scheduled in again, 3. we have called vcpu_put when we returned to userspace for it to issue another ioctl And therefore will not have a bg_timer programmed and the event is treated as a spurious wakeup from WFI if userspace decides to run the vcpu again even if there are not virtual interrupts. This fixes stray virtual timer interrupts triggered by an expiring hrtimer, which happens after a failed live migration, for instance. Fixes: bee038a6 ("KVM: arm/arm64: Rework the timer code to use a timer_map") Signed-off-by:Christoffer Dall <christoffer.dall@arm.com> Reported-by:
Andre Przywara <andre.przywara@arm.com> Tested-by:
Marc Zyngier <marc.zyngier@arm.com>
-
Suzuki K Poulose authored
With commit a80868f3, we no longer ensure that the THP page is properly aligned in the guest IPA. Skip the stage2 huge mapping for unaligned IPA backed by transparent hugepages. Fixes: a80868f3 ("KVM: arm/arm64: Enforce PTE mappings at stage2 when needed") Reported-by:
Eric Auger <eric.auger@redhat.com> Cc: Marc Zyngier <marc.zyngier@arm.com> Cc: Chirstoffer Dall <christoffer.dall@arm.com> Cc: Zenghui Yu <yuzenghui@huawei.com> Cc: Zheng Xiang <zhengxiang9@huawei.com> Cc: Andrew Murray <andrew.murray@arm.com> Cc: Eric Auger <eric.auger@redhat.com> Signed-off-by:
Suzuki K Poulose <suzuki.poulose@arm.com> Signed-off-by:
-
Andrew Jones authored
A failed KVM_ARM_VCPU_INIT should not set the vcpu target, as the vcpu target is used by kvm_vcpu_initialized() to determine if other vcpu ioctls may proceed. We need to set the target before calling kvm_reset_vcpu(), but if that call fails, we should then unset it and clear the feature bitmap while we're at it. Signed-off-by:
-
- 18 Apr, 2019 7 commits
-
-
Sean Christopherson authored
To minimize the latency of timer interrupts as observed by the guest, KVM adjusts the values it programs into the host timers to account for the host's overhead of programming and handling the timer event. In the event that the adjustments are too aggressive, i.e. the timer fires earlier than the guest expects, KVM busy waits immediately prior to entering the guest. Currently, KVM manually converts the delay from nanoseconds to clock cycles. But, the conversion is done in the guest's time domain, while the delay occurs in the host's time domain. This is perfectly ok when the guest and host are using the same TSC ratio, but if the guest is using a different ratio then the delay may not be accurate and could wait too little or too long. When the guest is not using the host's ratio, convert the delay from guest clock cycles to host nanoseconds and use ndelay() instead of __delay() to provide more accurate timing. Because converting to nanoseconds is relatively expensive, e.g. requires division and more multiplication ops, continue using __delay() directly when guest and host TSCs are running at the same ratio. Cc: Liran Alon <liran.alon@oracle.com> Cc: Wanpeng Li <wanpengli@tencent.com> Cc: stable@vger.kernel.org Fixes: 3b8a5df6 ("KVM: LAPIC: Tune lapic_timer_advance_ns automatically") Signed-off-by:
-
Sean Christopherson authored
The introduction of adaptive tuning of lapic timer advancement did not allow for the scenario where userspace would want to disable adaptive tuning but still employ timer advancement, e.g. for testing purposes or to handle a use case where adaptive tuning is unable to settle on a suitable time. This is epecially pertinent now that KVM places a hard threshold on the maximum advancment time. Rework the timer semantics to accept signed values, with a value of '-1' being interpreted as "use adaptive tuning with KVM's internal default", and any other value being used as an explicit advancement time, e.g. a time of '0' effectively disables advancement. Note, this does not completely restore the original behavior of lapic_timer_advance_ns. Prior to tracking the advancement per vCPU, which is necessary to support autotuning, userspace could adjust lapic_timer_advance_ns for *running* vCPU. With per-vCPU tracking, the module params are snapshotted at vCPU creation, i.e. applying a new advancement effectively requires restarting a VM. Dynamically updating a running vCPU is possible, e.g. a helper could be added to retrieve the desired delay, choosing between the global module param and the per-VCPU value depending on whether or not auto-tuning is (globally) enabled, but introduces a great deal of complexity. The wrapper itself is not complex, but understanding and documenting the effects of dynamically toggling auto-tuning and/or adjusting the timer advancement is nigh impossible since the behavior would be dependent on KVM's implementation as well as compiler optimizations. In other words, providing stable behavior would require extremely careful consideration now and in the future. Given that the expected use of a manually-tuned timer advancement is to "tune once, run many", use the vastly simpler approach of recognizing changes to the module params only when creating a new vCPU. Cc: Liran Alon <liran.alon@oracle.com> Cc: Wanpeng Li <wanpengli@tencent.com> Reviewed-by:
Liran Alon <liran.alon@oracle.com> Cc: stable@vger.kernel.org Fixes: 3b8a5df6 ("KVM: LAPIC: Tune lapic_timer_advance_ns automatically") Signed-off-by:
-
Sean Christopherson authored
Automatically adjusting the globally-shared timer advancement could corrupt the timer, e.g. if multiple vCPUs are concurrently adjusting the advancement value. That could be partially fixed by using a local variable for the arithmetic, but it would still be susceptible to a race when setting timer_advance_adjust_done. And because virtual_tsc_khz and tsc_scaling_ratio are per-vCPU, the correct calibration for a given vCPU may not apply to all vCPUs. Furthermore, lapic_timer_advance_ns is marked __read_mostly, which is effectively violated when finding a stable advancement takes an extended amount of timer. Opportunistically change the definition of lapic_timer_advance_ns to a u32 so that it matches the style of struct kvm_timer. Explicitly pass the param to kvm_create_lapic() so that it doesn't have to be exposed to lapic.c, thus reducing the probability of unintentionally using the global value instead of the per-vCPU value. Cc: Liran Alon <liran.alon@oracle.com> Cc: Wanpeng Li <wanpengli@tencent.com> Reviewed-by:
-
Sean Christopherson authored
To minimize the latency of timer interrupts as observed by the guest, KVM adjusts the values it programs into the host timers to account for the host's overhead of programming and handling the timer event. Now that the timer advancement is automatically tuned during runtime, it's effectively unbounded by default, e.g. if KVM is running as L1 the advancement can measure in hundreds of milliseconds. Disable timer advancement if adaptive tuning yields an advancement of more than 5000ns, as large advancements can break reasonable assumptions of the guest, e.g. that a timer configured to fire after 1ms won't arrive on the next instruction. Although KVM busy waits to mitigate the case of a timer event arriving too early, complications can arise when shifting the interrupt too far, e.g. kvm-unit-test's vmx.interrupt test will fail when its "host" exits on interrupts as KVM may inject the INTR before the guest executes STI+HLT. Arguably the unit test is "broken" in the sense that delaying a timer interrupt by 1ms doesn't technically guarantee the interrupt will arrive after STI+HLT, but it's a reasonable assumption that KVM should support. Furthermore, an unbounded advancement also effectively unbounds the time spent busy waiting, e.g. if the guest programs a timer with a very large delay. 5000ns is a somewhat arbitrary threshold. When running on bare metal, which is the intended use case, timer advancement is expected to be in the general vicinity of 1000ns. 5000ns is high enough that false positives are unlikely, while not being so high as to negatively affect the host's performance/stability. Note, a future patch will enable userspace to disable KVM's adaptive tuning, which will allow priveleged userspace will to specifying an advancement value in excess of this arbitrary threshold in order to satisfy an abnormal use case. Cc: Liran Alon <liran.alon@oracle.com> Cc: Wanpeng Li <wanpengli@tencent.com> Cc: stable@vger.kernel.org Fixes: 3b8a5df6 ("KVM: LAPIC: Tune lapic_timer_advance_ns automatically") Signed-off-by:
-
Vitaly Kuznetsov authored
It was reported that with some special Multi Processor Group configuration, e.g: bcdedit.exe /set groupsize 1 bcdedit.exe /set maxgroup on bcdedit.exe /set groupaware on for a 16-vCPU guest WS2012 shows BSOD on boot when PV TLB flush mechanism is in use. Tracing kvm_hv_flush_tlb immediately reveals the issue: kvm_hv_flush_tlb: processor_mask 0x0 address_space 0x0 flags 0x2 The only flag set in this request is HV_FLUSH_ALL_VIRTUAL_ADDRESS_SPACES, however, processor_mask is 0x0 and no HV_FLUSH_ALL_PROCESSORS is specified. We don't flush anything and apparently it's not what Windows expects. TLFS doesn't say anything about such requests and newer Windows versions seem to be unaffected. This all feels like a WS2012 bug, which is, however, easy to workaround in KVM: let's flush everything when we see an empty flush request, over-flushing doesn't hurt. Signed-off-by:
-
Liran Alon authored
If guest sets MSR_IA32_TSCDEADLINE to value such that in host time-domain it's shorter than lapic_timer_advance_ns, we can reach a case that we call hrtimer_start() with expiration time set at the past. Because lapic_timer.timer is init with HRTIMER_MODE_ABS_PINNED, it is not allowed to run in softirq and therefore will never expire. To avoid such a scenario, verify that deadline expiration time is set on host time-domain further than (now + lapic_timer_advance_ns). A future patch can also consider adding a min_timer_deadline_ns module parameter, similar to min_timer_period_us to avoid races that amount of ns it takes to run logic could still call hrtimer_start() with expiration timer set at the past. Reviewed-by:
Joao Martins <joao.m.martins@oracle.com> Signed-off-by:
-
Paolo Bonzini authored
Merge tag 'kvm-ppc-fixes-5.1-1' of git://git.kernel.org/pub/scm/linux/kernel/git/paulus/powerpc into HEAD KVM/PPC fixes for 5.1 - Fix host hang in the HTM assist code for POWER9 - Take srcu read lock around memslot lookup
-
- 16 Apr, 2019 20 commits
-
-
Vitaly Kuznetsov authored
In __apic_accept_irq() interface trig_mode is int and actually on some code paths it is set above u8: kvm_apic_set_irq() extracts it from 'struct kvm_lapic_irq' where trig_mode is u16. This is done on purpose as e.g. kvm_set_msi_irq() sets it to (1 << 15) & e->msi.data kvm_apic_local_deliver sets it to reg & (1 << 15). Fix the immediate issue by making 'tm' into u16. We may also want to adjust __apic_accept_irq() interface and use proper sizes for vector, level, trig_mode but this is not urgent. Signed-off-by:
-
Paolo Bonzini authored
These were found with smatch, and then generalized when applicable. Signed-off-by: -
Hariprasad Kelam authored
Changed passing argument as "0 to NULL" which resolves below sparse warning arch/x86/kvm/x86.c:3096:61: warning: Using plain integer as NULL pointer Signed-off-by:
Hariprasad Kelam <hariprasad.kelam@gmail.com> Signed-off-by:
-
Vitaly Kuznetsov authored
Add a simple test for SMM, based on VMX. The test implements its own sync between the guest and the host as using our ucall library seems to be too cumbersome: SMI handler is happening in real-address mode. This patch also fixes KVM_SET_NESTED_STATE to happen after KVM_SET_VCPU_EVENTS, in fact it places it last. This is because KVM needs to know whether the processor is in SMM or not. Signed-off-by:
-
Paolo Bonzini authored
-no-pie was added to GCC at the same time as their configuration option --enable-default-pie. Compilers that were built before do not have -no-pie, but they also do not need it. Detect the option at build time. Signed-off-by: -
Paolo Bonzini authored
Starting state migration after an IO exit without first completing IO may result in test failures. We already have two tests that need this (this patch in fact fixes evmcs_test, similar to what was fixed for state_test in commit 0f73bbc8, "KVM: selftests: complete IO before migrating guest state", 2019-03-13) and a third is coming. So, move the code to vcpu_save_state, and while at it do not access register state until after I/O is complete. Signed-off-by:
-
Sean Christopherson authored
Invoking the 64-bit variation on a 32-bit kenrel will crash the guest, trigger a WARN, and/or lead to a buffer overrun in the host, e.g. rsm_load_state_64() writes r8-r15 unconditionally, but enum kvm_reg and thus x86_emulate_ctxt._regs only define r8-r15 for CONFIG_X86_64. KVM allows userspace to report long mode support via CPUID, even though the guest is all but guaranteed to crash if it actually tries to enable long mode. But, a pure 32-bit guest that is ignorant of long mode will happily plod along. SMM complicates things as 64-bit CPUs use a different SMRAM save state area. KVM handles this correctly for 64-bit kernels, e.g. uses the legacy save state map if userspace has hid long mode from the guest, but doesn't fare well when userspace reports long mode support on a 32-bit host kernel (32-bit KVM doesn't support 64-bit guests). Since the alternative is to crash the guest, e.g. by not loading state or explicitly requesting shutdown, unconditionally use the legacy SMRAM save state map for 32-bit KVM. If a guest has managed to get far enough to handle SMIs when running under a weird/buggy userspace hypervisor, then don't deliberately crash the guest since there are no downsides (from KVM's perspective) to allow it to continue running. Fixes: 660a5d51 ("KVM: x86: save/load state on SMM switch") Cc: stable@vger.kernel.org Signed-off-by:
-
Sean Christopherson authored
Neither AMD nor Intel CPUs have an EFER field in the legacy SMRAM save state area, i.e. don't save/restore EFER across SMM transitions. KVM somewhat models this, e.g. doesn't clear EFER on entry to SMM if the guest doesn't support long mode. But during RSM, KVM unconditionally clears EFER so that it can get back to pure 32-bit mode in order to start loading CRs with their actual non-SMM values. Clear EFER only when it will be written when loading the non-SMM state so as to preserve bits that can theoretically be set on 32-bit vCPUs, e.g. KVM always emulates EFER_SCE. And because CR4.PAE is cleared only to play nice with EFER, wrap that code in the long mode check as well. Note, this may result in a compiler warning about cr4 being consumed uninitialized. Re-read CR4 even though it's technically unnecessary, as doing so allows for more readable code and RSM emulation is not a performance critical path. Fixes: 660a5d51 ("KVM: x86: save/load state on SMM switch") Cc: stable@vger.kernel.org Signed-off-by:
-
Sean Christopherson authored
RSM emulation is currently broken on VMX when the interrupted guest has CR4.VMXE=1. Stop dancing around the issue of HF_SMM_MASK being set when loading SMSTATE into architectural state, e.g. by toggling it for problematic flows, and simply clear HF_SMM_MASK prior to loading architectural state (from SMRAM save state area). Reported-by:
Jon Doron <arilou@gmail.com> Cc: Jim Mattson <jmattson@google.com> Cc: Liran Alon <liran.alon@oracle.com> Cc: Vitaly Kuznetsov <vkuznets@redhat.com> Fixes: 5bea5123 ("KVM: VMX: check nested state and CR4.VMXE against SMM") Signed-off-by:
-
Sean Christopherson authored
Prepare for clearing HF_SMM_MASK prior to loading state from the SMRAM save state map, i.e. kvm_smm_changed() needs to be called after state has been loaded and so cannot be done automatically when setting hflags from RSM. Signed-off-by:
-
Sean Christopherson authored
RSM emulation is currently broken on VMX when the interrupted guest has CR4.VMXE=1. Rather than dance around the issue of HF_SMM_MASK being set when loading SMSTATE into architectural state, ideally RSM emulation itself would be reworked to clear HF_SMM_MASK prior to loading non-SMM architectural state. Ostensibly, the only motivation for having HF_SMM_MASK set throughout the loading of state from the SMRAM save state area is so that the memory accesses from GET_SMSTATE() are tagged with role.smm. Load all of the SMRAM save state area from guest memory at the beginning of RSM emulation, and load state from the buffer instead of reading guest memory one-by-one. This paves the way for clearing HF_SMM_MASK prior to loading state, and also aligns RSM with the enter_smm() behavior, which fills a buffer and writes SMRAM save state in a single go. Signed-off-by:
-
Liran Alon authored
Issue was discovered when running kvm-unit-tests on KVM running as L1 on top of Hyper-V. When vmx_instruction_intercept unit-test attempts to run RDPMC to test RDPMC-exiting, it is intercepted by L1 KVM which it's EXIT_REASON_RDPMC handler raise #GP because vCPU exposed by Hyper-V doesn't support PMU. Instead of unit-test expectation to be reflected with EXIT_REASON_RDPMC. The reason vmx_instruction_intercept unit-test attempts to run RDPMC even though Hyper-V doesn't support PMU is because L1 expose to L2 support for RDPMC-exiting. Which is reasonable to assume that is supported only in case CPU supports PMU to being with. Above issue can easily be simulated by modifying vmx_instruction_intercept config in x86/unittests.cfg to run QEMU with "-cpu host,+vmx,-pmu" and run unit-test. To handle issue, change KVM to expose RDPMC-exiting only when guest supports PMU. Reported-by:
Saar Amar <saaramar@microsoft.com> Reviewed-by:
Mihai Carabas <mihai.carabas@oracle.com> Reviewed-by:
-
Liran Alon authored
Before this change, reading a VMware pseduo PMC will succeed even when PMU is not supported by guest. This can easily be seen by running kvm-unit-test vmware_backdoors with "-cpu host,-pmu" option. Reviewed-by:
-
WANG Chao authored
guest xcr0 could leak into host when MCE happens in guest mode. Because do_machine_check() could schedule out at a few places. For example: kvm_load_guest_xcr0 ... kvm_x86_ops->run(vcpu) { vmx_vcpu_run vmx_complete_atomic_exit kvm_machine_check do_machine_check do_memory_failure memory_failure lock_page In this case, host_xcr0 is 0x2ff, guest vcpu xcr0 is 0xff. After schedule out, host cpu has guest xcr0 loaded (0xff). In __switch_to { switch_fpu_finish copy_kernel_to_fpregs XRSTORS If any bit i in XSTATE_BV[i] == 1 and xcr0[i] == 0, XRSTORS will generate #GP (In this case, bit 9). Then ex_handler_fprestore kicks in and tries to reinitialize fpu by restoring init fpu state. Same story as last #GP, except we get DOUBLE FAULT this time. Cc: stable@vger.kernel.org Signed-off-by:WANG Chao <chao.wang@ucloud.cn> Signed-off-by:
-
Vitaly Kuznetsov authored
I noticed that apic test from kvm-unit-tests always hangs on my EPYC 7401P, the hanging test nmi-after-sti is trying to deliver 30000 NMIs and tracing shows that we're sometimes able to deliver a few but never all. When we're trying to inject an NMI we may fail to do so immediately for various reasons, however, we still need to inject it so enable_nmi_window() arms nmi_singlestep mode. #DB occurs as expected, but we're not checking for pending NMIs before entering the guest and unless there's a different event to process, the NMI will never get delivered. Make KVM_REQ_EVENT request on the vCPU from db_interception() to make sure pending NMIs are checked and possibly injected. Signed-off-by:
-
Suthikulpanit, Suravee authored
Only clear the valid bit when invalidate logical APIC id entry. The current logic clear the valid bit, but also set the rest of the bits (including reserved bits) to 1. Fixes: 98d90582 ('svm: Fix AVIC DFR and LDR handling') Signed-off-by:
Suravee Suthikulpanit <suravee.suthikulpanit@amd.com> Cc: stable@vger.kernel.org Signed-off-by:
-
Suthikulpanit, Suravee authored
This reverts commit bb218fbc. As Oren Twaig pointed out the old discussion: https://patchwork.kernel.org/patch/8292231/ that the change coud potentially cause an extra IPI to be sent to the destination vcpu because the AVIC hardware already set the IRR bit before the incomplete IPI #VMEXIT with id=1 (target vcpu is not running). Since writting to ICR and ICR2 will also set the IRR. If something triggers the destination vcpu to get scheduled before the emulation finishes, then this could result in an additional IPI. Also, the issue mentioned in the commit bb218fbc was misdiagnosed. Cc: Radim Krčmář <rkrcmar@redhat.com> Cc: Paolo Bonzini <pbonzini@redhat.com> Reported-by:
Oren Twaig <oren@scalemp.com> Signed-off-by:
-
Ben Gardon authored
KVM bases its memory usage limits on the total number of guest pages across all memslots. However, those limits, and the calculations to produce them, use 32 bit unsigned integers. This can result in overflow if a VM has more guest pages that can be represented by a u32. As a result of this overflow, KVM can use a low limit on the number of MMU pages it will allocate. This makes KVM unable to map all of guest memory at once, prompting spurious faults. Tested: Ran all kvm-unit-tests on an Intel Haswell machine. This patch introduced no new failures. Signed-off-by:
Ben Gardon <bgardon@google.com> Cc: stable@vger.kernel.org Signed-off-by:
-
Paolo Bonzini authored
The remaining failures of vmx.flat when EPT is disabled are caused by incorrectly reflecting VMfails to the L1 hypervisor. What happens is that nested_vmx_restore_host_state corrupts the guest CR3, reloading it with the host's shadow CR3 instead, because it blindly loads GUEST_CR3 from the vmcs01. For simplicity let's just always use hardware VMCS checks when EPT is disabled. This way, nested_vmx_restore_host_state is not reached at all (or at least shouldn't be reached). Signed-off-by: -
Paolo Bonzini authored
As mentioned in the comment, there are some special cases where we can simply clear the TPR shadow bit from the CPU-based execution controls in the vmcs02. Handle them so that we can remove some XFAILs from vmx.flat. Signed-off-by:
-
- 15 Apr, 2019 1 commit
-
-
Sean Christopherson authored
A recently introduced helper for handling zap vs. remote flush incorrectly bails early, effectively leaking defunct shadow pages. Manifests as a slab BUG when exiting KVM due to the shadow pages being alive when their associated cache is destroyed. ========================================================================== BUG kvm_mmu_page_header: Objects remaining in kvm_mmu_page_header on ... -------------------------------------------------------------------------- Disabling lock debugging due to kernel taint INFO: Slab 0x00000000fc436387 objects=26 used=23 fp=0x00000000d023caee ... CPU: 6 PID: 4315 Comm: rmmod Tainted: G B 5.1.0-rc2+ #19 Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS 0.0.0 02/06/2015 Call Trace: dump_stack+0x46/0x5b slab_err+0xad/0xd0 ? on_each_cpu_mask+0x3c/0x50 ? ksm_migrate_page+0x60/0x60 ? on_each_cpu_cond_mask+0x7c/0xa0 ? __kmalloc+0x1ca/0x1e0 __kmem_cache_shutdown+0x13a/0x310 shutdown_cache+0xf/0x130 kmem_cache_destroy+0x1d5/0x200 kvm_mmu_module_exit+0xa/0x30 [kvm] kvm_arch_exit+0x45/0x60 [kvm] kvm_exit+0x6f/0x80 [kvm] vmx_exit+0x1a/0x50 [kvm_intel] __x64_sys_delete_module+0x153/0x1f0 ? exit_to_usermode_loop+0x88/0xc0 do_syscall_64+0x4f/0x100 entry_SYSCALL_64_after_hwframe+0x44/0xa9 Fixes: a2113634 ("KVM: x86/mmu: Split remote_flush+zap case out of kvm_mmu_flush_or_zap()") Signed-off-by:
-
