- 23 Mar, 2020 6 commits
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Sean Christopherson authored
VMCLEAR all in-use VMCSes during a crash, even if kdump's NMI shootdown interrupted a KVM update of the percpu in-use VMCS list. Because NMIs are not blocked by disabling IRQs, it's possible that crash_vmclear_local_loaded_vmcss() could be called while the percpu list of VMCSes is being modified, e.g. in the middle of list_add() in vmx_vcpu_load_vmcs(). This potential corner case was called out in the original commit[*], but the analysis of its impact was wrong. Skipping the VMCLEARs is wrong because it all but guarantees that a loaded, and therefore cached, VMCS will live across kexec and corrupt memory in the new kernel. Corruption will occur because the CPU's VMCS cache is non-coherent, i.e. not snooped, and so the writeback of VMCS memory on its eviction will overwrite random memory in the new kernel. The VMCS will live because the NMI shootdown also disables VMX, i.e. the in-progress VMCLEAR will #UD, and existing Intel CPUs do not flush the VMCS cache on VMXOFF. Furthermore, interrupting list_add() and list_del() is safe due to crash_vmclear_local_loaded_vmcss() using forward iteration. list_add() ensures the new entry is not visible to forward iteration unless the entire add completes, via WRITE_ONCE(prev->next, new). A bad "prev" pointer could be observed if the NMI shootdown interrupted list_del() or list_add(), but list_for_each_entry() does not consume ->prev. In addition to removing the temporary disabling of VMCLEAR, open code loaded_vmcs_init() in __loaded_vmcs_clear() and reorder VMCLEAR so that the VMCS is deleted from the list only after it's been VMCLEAR'd. Deleting the VMCS before VMCLEAR would allow a race where the NMI shootdown could arrive between list_del() and vmcs_clear() and thus neither flow would execute a successful VMCLEAR. Alternatively, more code could be moved into loaded_vmcs_init(), but that gets rather silly as the only other user, alloc_loaded_vmcs(), doesn't need the smp_wmb() and would need to work around the list_del(). Update the smp_*() comments related to the list manipulation, and opportunistically reword them to improve clarity. [*] https://patchwork.kernel.org/patch/1675731/#3720461 Fixes: 8f536b76 ("KVM: VMX: provide the vmclear function and a bitmap to support VMCLEAR in kdump") Cc: stable@vger.kernel.org Signed-off-by:
Sean Christopherson <sean.j.christopherson@intel.com> Message-Id: <20200321193751.24985-2-sean.j.christopherson@intel.com> Reviewed-by:
Vitaly Kuznetsov <vkuznets@redhat.com> Signed-off-by:
Paolo Bonzini <pbonzini@redhat.com>
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Zhenyu Wang authored
For CPU supporting fast short REP MOV (XF86_FEATURE_FSRM) e.g Icelake, Tigerlake, expose it in KVM supported cpuid as well. Signed-off-by:
Zhenyu Wang <zhenyuw@linux.intel.com> Message-Id: <20200323092236.3703-1-zhenyuw@linux.intel.com> Signed-off-by:
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Stefan Raspl authored
Add an alternative format that can be more easily used for further processing later on. Note that we add a timestamp in the first column for both, the regular and the new csv format. Signed-off-by:
Stefan Raspl <raspl@linux.ibm.com> Message-Id: <20200306114250.57585-5-raspl@linux.ibm.com> Signed-off-by:
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Stefan Raspl authored
This now controls both, the refresh rate of the interactive mode as well as the logging mode. Which, as a consequence, means that the default of logging mode is now 3s, too (use command line switch '-s' to adjust to your liking). Signed-off-by:
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Stefan Raspl authored
optparse is deprecated for a while, hence switching over to argparse (which also works with python2). As a consequence, help output has some subtle changes, the most significant one being that the options are all listed explicitly instead of a universal '[options]' indicator. Also, some of the error messages are phrased slightly different. While at it, squashed a number of minor PEP8 issues. Signed-off-by:
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Stefan Raspl authored
Make sure command line arguments are sorted alphabetically everywhere, and adjusted existing texts for interactive command 's' to become consistent with the long form --set-delay. Throwing in some PEP8 fixes (all cosmetics) for good measure. Signed-off-by:
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- 18 Mar, 2020 7 commits
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Andrew Jones authored
The steal_time test's timespec stop condition was wrong and should have used the timespec functions instead to avoid being wrong, but timespec_diff had a strange interface. Rework all the timespec API and its use. Signed-off-by:
Andrew Jones <drjones@redhat.com> Signed-off-by:
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Xiaoyao Li authored
In kvm_arch_dev_ioctl(), the brackets of case KVM_X86_GET_MCE_CAP_SUPPORTED accidently encapsulates case KVM_GET_MSR_FEATURE_INDEX_LIST and case KVM_GET_MSRS. It doesn't affect functionality but it's misleading. Remove unnecessary brackets and opportunistically add a "break" in the default path. Suggested-by:
Xiaoyao Li <xiaoyao.li@intel.com> Reviewed-by:
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Sean Christopherson authored
Tack on "used max basic" at the end of the CPUID tracepoint when the output values correspond to the max basic leaf, i.e. when emulating Intel's out-of-range CPUID behavior. Observing "cpuid entry not found" in the tracepoint with non-zero output values is confusing for users that aren't familiar with the out-of-range semantics, and qualifying the "not found" case hopefully makes it clear that "found" means "found the exact entry". Suggested-by:
Jan Kiszka <jan.kiszka@siemens.com> Signed-off-by:
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Sean Christopherson authored
Output the requested index when tracing CPUID emulation; it's basically mandatory for leafs where the index is meaningful, and is helpful for verifying KVM correctness even when the index isn't meaningful, e.g. the trace for a Linux guest's hypervisor_cpuid_base() probing appears to be broken (returns all zeroes) at first glance, but is correct because the index is non-zero, i.e. the output values correspond to a random index in the maximum basic leaf. Suggested-by:
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Paolo Bonzini authored
EFER is set for L2 using svm_set_efer, which hardcodes EFER_SVME to 1 and hides an incorrect value for EFER.SVME in the L1 VMCB. Perform the check manually to detect invalid guest state. Reported-by:
Krish Sadhukhan <krish.sadhukhan@oracle.com> Signed-off-by:
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Zhenyu Wang authored
On Tigerlake new AVX512 VP2INTERSECT feature is available. This allows to expose it via KVM_GET_SUPPORTED_CPUID. Cc: "Zhong, Yang" <yang.zhong@intel.com> Signed-off-by:
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Paolo Bonzini authored
The name of nested_vmx_exit_reflected suggests that it's purely a test, but it actually marks VMCS12 pages as dirty. Move this to vmx_handle_exit, observing that the initial nested_run_pending check in nested_vmx_exit_reflected is pointless---nested_run_pending has just been cleared in vmx_vcpu_run and won't be set until handle_vmlaunch or handle_vmresume. Suggested-by:
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- 17 Mar, 2020 1 commit
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Uros Bizjak authored
Registers in "regs" array are indexed as rax/rcx/rdx/.../rsi/rdi/r8/... Reorder access to "regs" array in vmenter.S to follow its natural order. Signed-off-by:
Uros Bizjak <ubizjak@gmail.com> Signed-off-by:
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- 16 Mar, 2020 26 commits
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Paolo Bonzini authored
Merge tag 'kvm-s390-next-5.7-1' of git://git.kernel.org/pub/scm/linux/kernel/git/kvms390/linux into HEAD KVM: s390: Features and Enhancements for 5.7 part1 1. Allow to disable gisa 2. protected virtual machines Protected VMs (PVM) are KVM VMs, where KVM can't access the VM's state like guest memory and guest registers anymore. Instead the PVMs are mostly managed by a new entity called Ultravisor (UV), which provides an API, so KVM and the PV can request management actions. PVMs are encrypted at rest and protected from hypervisor access while running. They switch from a normal operation into protected mode, so we can still use the standard boot process to load a encrypted blob and then move it into protected mode. Rebooting is only possible by passing through the unprotected/normal mode and switching to protected again. One mm related patch will go via Andrews mm tree ( mm/gup/writeback: add callbacks for inaccessible pages)
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Vitaly Kuznetsov authored
Check that guest doesn't hang when an invalid eVMCS GPA is specified. Testing that #UD is injected would probably be better but selftests lack the infrastructure currently. Signed-off-by:
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Vitaly Kuznetsov authored
Check that VMfailInvalid happens when eVMCS revision is is invalid. Signed-off-by:
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Vitaly Kuznetsov authored
KVM allows to use revision_id from MSR_IA32_VMX_BASIC as eVMCS revision_id to workaround a bug in genuine Hyper-V (see the comment in nested_vmx_handle_enlightened_vmptrld()), this shouldn't be used by default. Switch to using KVM_EVMCS_VERSION(1). Signed-off-by:
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Vitaly Kuznetsov authored
nested_vmx_handle_enlightened_vmptrld() fails in two cases: - when we fail to kvm_vcpu_map() the supplied GPA - when revision_id is incorrect. Genuine Hyper-V raises #UD in the former case (at least with *some* incorrect GPAs) and does VMfailInvalid() in the later. KVM doesn't do anything so L1 just gets stuck retrying the same faulty VMLAUNCH. nested_vmx_handle_enlightened_vmptrld() has two call sites: nested_vmx_run() and nested_get_vmcs12_pages(). The former needs to queue do much: the failure there happens after migration when L2 was running (and L1 did something weird like wrote to VP assist page from a different vCPU), just kill L1 with KVM_EXIT_INTERNAL_ERROR. Reported-by:
Miaohe Lin <linmiaohe@huawei.com> Signed-off-by:
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Vitaly Kuznetsov authored
When vmx_set_nested_state() happens, we may not have all the required data to map enlightened VMCS: e.g. HV_X64_MSR_VP_ASSIST_PAGE MSR may not yet be restored so we need a postponed action. Currently, we (ab)use need_vmcs12_to_shadow_sync/nested_sync_vmcs12_to_shadow() for that but this is not ideal: - We may not need to sync anything if L2 is running - It is hard to propagate errors from nested_sync_vmcs12_to_shadow() as we call it from vmx_prepare_switch_to_guest() which happens just before we do VMLAUNCH, the code is not ready to handle errors there. Move eVMCS mapping to nested_get_vmcs12_pages() and request KVM_REQ_GET_VMCS12_PAGES, it seems to be is less abusive in nature. It would probably be possible to introduce a specialized KVM_REQ_EVMCS_MAP but it is undesirable to propagate eVMCS specifics all the way up to x86.c Note, we don't need to request KVM_REQ_GET_VMCS12_PAGES from vmx_set_nested_state() directly as nested_vmx_enter_non_root_mode() already does that. Requesting KVM_REQ_GET_VMCS12_PAGES is done to document the (non-obvious) side-effect and to be future proof. Signed-off-by:
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Paolo Bonzini authored
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Wainer dos Santos Moschetta authored
Changed all tests and utilities to use TEST_FAIL macro instead of TEST_ASSERT(false,...). Signed-off-by:
Wainer dos Santos Moschetta <wainersm@redhat.com> Signed-off-by:
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Wainer dos Santos Moschetta authored
Some tests/utilities use the TEST_ASSERT(false, ...) pattern to indicate a failure and stop execution. This change introduces the TEST_FAIL macro which is a wrap around TEST_ASSERT(false, ...) and so provides a direct alternative for failing a test. Signed-off-by:
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Christian Borntraeger authored
Normal reset and initial CPU reset do not clear all registers. Add a test that those registers are NOT changed. Signed-off-by:
Christian Borntraeger <borntraeger@de.ibm.com> Signed-off-by:
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Christian Borntraeger authored
We should not only test the oneregs or the get_(x)regs interfaces but also the sync_regs. Those are usually the canonical place for register content. Signed-off-by:
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Christian Borntraeger authored
The guest crashes very early due to changes in the control registers used by dynamic address translation. Let us use different registers that will not crash the guest. Signed-off-by:
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Andrew Jones authored
The steal-time test confirms what is reported to the guest as stolen time is consistent with the run_delay reported for the VCPU thread on the host. Both x86_64 and AArch64 have the concept of steal/stolen time so this test is introduced for both architectures. While adding the test we ensure .gitignore has all tests listed (it was missing s390x/resets) and that the Makefile has all tests listed in alphabetical order (not really necessary, but it almost was already...). We also extend the common API with a new num-guest- pages call and a new timespec call. Signed-off-by:
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Andrew Jones authored
Also correct the comment and prototype for vm_create_default(), as it takes a number of pages, not a size. Signed-off-by:
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Andrew Jones authored
Signed-off-by:
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Andrew Jones authored
Use the format attribute to enable printf format warnings, and then fix them all. Signed-off-by:
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Christian Borntraeger authored
acrs are 32 bit and not 64 bit. Reported-by:
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Christian Borntraeger authored
value is u64 and not string. Reported-by:
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Andrew Jones authored
Move function documentation comment blocks to the header files in order to avoid duplicating them for each architecture. While at it clean up and fix up the comment blocks. Signed-off-by:
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Andrew Jones authored
Add svm_vmcall_test to gitignore list, and realphabetize it. Signed-off-by:
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Miaohe Lin authored
The function does not return bool anymore. Signed-off-by:
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Paolo Bonzini authored
After test_and_set_bit() for kvm->arch.apicv_inhibit_reasons, we will always get false when calling kvm_apicv_activated() because it's sure apicv_inhibit_reasons do not equal to 0. What the code wants to do, is check whether APICv was *already* active and if so skip the costly request; we can do this using cmpxchg. Reported-by:
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Oliver Upton authored
commit 5ef8acbd ("KVM: nVMX: Emulate MTF when performing instruction emulation") introduced a helper to check the MTF VM-execution control in vmcs12. Change pre-existing check in nested_vmx_exit_reflected() to instead use the helper. Signed-off-by:
Oliver Upton <oupton@google.com> Reviewed-by:
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Wanpeng Li authored
PMU is not exposed to guest by most of products from cloud providers since the bad performance of PMU emulation and security concern. However, it calls perf_guest_switch_get_msrs() and clear_atomic_switch_msr() unconditionally even if PMU is not exposed to the guest before each vmentry. ~2% vmexit time reduced can be observed by kvm-unit-tests/vmexit.flat on my SKX server. Before patch: vmcall 1559 After patch: vmcall 1529 Signed-off-by:
Wanpeng Li <wanpengli@tencent.com> Signed-off-by:
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Andrew Jones authored
s390 requires 1M aligned guest sizes. Embedding the rounding in vm_adjust_num_guest_pages() allows us to remove it from a few other places. Signed-off-by:
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Suravee Suthikulpanit authored
GA Log tracepoint is useful when debugging AVIC performance issue as it can be used with perf to count the number of times IOMMU AVIC injects interrupts through the slow-path instead of directly inject interrupts to the target vcpu. Signed-off-by:
Suravee Suthikulpanit <suravee.suthikulpanit@amd.com> Signed-off-by:
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