The IOAPIC has an 'Extended Destination ID' field in its RTE, which maps
to bits 11-4 of the MSI address. Since those address bits fall within a
given 4KiB page they were historically non-trivial to use on real hardware.
The Intel IOMMU uses the lowest bit to indicate a remappable format MSI,
and then the remaining 7 bits are part of the index.
Where the remappable format bit isn't set, we can actually use the other
seven to allow external (IOAPIC and MSI) interrupts to reach up to 32768
CPUs instead of just the 255 permitted on bare metal.
Signed-off-by: David Woodhouse <dwmw@amazon.co.uk>
Message-Id: <78097f9218300e63e751e077a0a5ca029b56ba46.camel@infradead.org>
[Fix UBSAN warning. - Paolo]
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Signed-off-by: David Woodhouse <dwmw2@infradead.org>
Currently, the nested state format is hardcoded to VMX. This will result
in kvm_put_nested_state() returning an error because the KVM SVM support
checks for the nested state to be KVM_STATE_NESTED_FORMAT_SVM. As a
result, kvm_arch_put_registers() errors out early.
Update the setting of the format based on the virtualization feature:
VMX - KVM_STATE_NESTED_FORMAT_VMX
SVM - KVM_STATE_NESTED_FORMAT_SVM
Also, fix the code formatting while at it.
Fixes: b16c0e20c7 ("KVM: add support for AMD nested live migration")
Cc: Eduardo Habkost <ehabkost@redhat.com>
Cc: Richard Henderson <richard.henderson@linaro.org>
Cc: Paolo Bonzini <pbonzini@redhat.com>
Cc: Marcelo Tosatti <mtosatti@redhat.com>
Signed-off-by: Tom Lendacky <thomas.lendacky@amd.com>
Message-Id: <fe53d00fe0d884e812960781284cd48ae9206acc.1605546140.git.thomas.lendacky@amd.com>
Cc: qemu-stable@nongnu.org
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
As IRQ routing is always available on x86,
kvm_allows_irq0_override() will always return true, so we don't
need the function anymore.
Signed-off-by: Eduardo Habkost <ehabkost@redhat.com>
Acked-by: Paolo Bonzini <pbonzini@redhat.com>
Message-Id: <20200922201922.2153598-4-ehabkost@redhat.com>
Signed-off-by: Eduardo Habkost <ehabkost@redhat.com>
KVM_CAP_IRQ_ROUTING is always available on x86, so replace checks
for kvm_has_gsi_routing() and KVM_CAP_IRQ_ROUTING with asserts.
Signed-off-by: Eduardo Habkost <ehabkost@redhat.com>
Acked-by: Paolo Bonzini <pbonzini@redhat.com>
Message-Id: <20200922201922.2153598-3-ehabkost@redhat.com>
Signed-off-by: Eduardo Habkost <ehabkost@redhat.com>
KVM_CAP_IRQ_ROUTING is available since 2009 (Linux v2.6.30), so
it's safe to just make it a requirement on x86.
Signed-off-by: Eduardo Habkost <ehabkost@redhat.com>
Acked-by: Paolo Bonzini <pbonzini@redhat.com>
Message-Id: <20200922201922.2153598-2-ehabkost@redhat.com>
Signed-off-by: Eduardo Habkost <ehabkost@redhat.com>
Fix typo to use correct edx value for FEATURE_HYPERV_EDX when
hyperv_passthrough is enabled.
Signed-off-by: Zhenyu Wang <zhenyuw@linux.intel.com>
Message-Id: <20190820103030.12515-1-zhenyuw@linux.intel.com>
Fixes: e48ddcc6ce ("i386/kvm: implement 'hv-passthrough' mode")
Signed-off-by: Eduardo Habkost <ehabkost@redhat.com>
Post memory failure event through QMP to handle hardware memory corrupted
event. Rather than simply printing to the log, QEMU could report more
effective message to the client. For example, if a guest receives an MCE,
evacuating the host could be a good idea.
Signed-off-by: zhenwei pi <pizhenwei@bytedance.com>
Message-Id: <20200930100440.1060708-4-pizhenwei@bytedance.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Paravirtualized features have been listed in KVM_GET_SUPPORTED_CPUID since
Linux 2.6.35 (commit 84478c829d0f, "KVM: x86: export paravirtual cpuid flags
in KVM_GET_SUPPORTED_CPUID", 2010-05-19). It has been more than 10 years,
so remove the fallback code.
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
QEMU's kvmclock device is only created when KVM PV feature bits for
kvmclock (KVM_FEATURE_CLOCKSOURCE/KVM_FEATURE_CLOCKSOURCE2) are
exposed to the guest. With 'kvm=off' cpu flag the device is not
created and we don't call KVM_GET_CLOCK/KVM_SET_CLOCK upon migration.
It was reported that without these call at least Hyper-V TSC page
clocksouce (which can be enabled independently) gets broken after
migration.
Switch to creating kvmclock QEMU device unconditionally, it seems
to always make sense to call KVM_GET_CLOCK/KVM_SET_CLOCK on migration.
Use KVM_CAP_ADJUST_CLOCK check instead of CPUID feature bits.
Reported-by: Antoine Damhet <antoine.damhet@blade-group.com>
Suggested-by: Paolo Bonzini <pbonzini@redhat.com>
Signed-off-by: Vitaly Kuznetsov <vkuznets@redhat.com>
Message-Id: <20200922151934.899555-1-vkuznets@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
VM with interrupt based APF enabled fails to migrate:
qemu-system-x86_64: error: failed to set MSR 0x4b564d02 to 0xf3
We have two issues:
1) There is a typo in kvm_put_msrs() and we write async_pf_int_msr
to MSR_KVM_ASYNC_PF_EN (instead of MSR_KVM_ASYNC_PF_INT)
2) We restore MSR_KVM_ASYNC_PF_EN before MSR_KVM_ASYNC_PF_INT is set
and this violates the check in KVM.
Re-order MSR_KVM_ASYNC_PF_EN/MSR_KVM_ASYNC_PF_INT setting (and
kvm_get_msrs() for consistency) and fix the typo.
Signed-off-by: Vitaly Kuznetsov <vkuznets@redhat.com>
Message-Id: <20200917102316.814804-1-vkuznets@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Linux-5.8 introduced interrupt based mechanism for 'page ready' events
delivery and disabled the old, #PF based one (see commit 2635b5c4a0e4
"KVM: x86: interrupt based APF 'page ready' event delivery"). Linux
guest switches to using in in 5.9 (see commit b1d405751cd5 "KVM: x86:
Switch KVM guest to using interrupts for page ready APF delivery").
The feature has a new KVM_FEATURE_ASYNC_PF_INT bit assigned and
the interrupt vector is set in MSR_KVM_ASYNC_PF_INT MSR. Support this
in QEMU.
Signed-off-by: Vitaly Kuznetsov <vkuznets@redhat.com>
Message-Id: <20200908141206.357450-1-vkuznets@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Hyper-V TLFS prior to version 6.0 had a mistake in it: special value
'0xffffffff' for CPUID 0x40000004.EBX was called 'never to retry', this
looked weird (like why it's not '0' which supposedly have the same effect?)
but nobody raised the question. In TLFS version 6.0 the mistake was
corrected to 'never notify' which sounds logical. Fix QEMU accordingly.
Signed-off-by: Vitaly Kuznetsov <vkuznets@redhat.com>
Message-Id: <20200515114847.74523-1-vkuznets@redhat.com>
Signed-off-by: Eduardo Habkost <ehabkost@redhat.com>
Let's make this file compilable with -Werror=implicit-fallthrough :
Looking at the code, it seems like the fallthrough is intended here,
so we should add the corresponding "/* fallthrough */" comment here.
Signed-off-by: Thomas Huth <thuth@redhat.com>
Acked-by: Paolo Bonzini <pbonzini@redhat.com>
Message-Id: <20200911125301.413081-1-thuth@redhat.com>
Signed-off-by: Laurent Vivier <laurent@vivier.eu>
In order to use inclusive terminology, rename host_tsx_blacklisted()
as host_tsx_broken().
Signed-off-by: Philippe Mathieu-Daudé <philmd@redhat.com>
Reviewed-by: Thomas Huth <thuth@redhat.com>
Acked-by: Paolo Bonzini <pbonzini@redhat.com>
Message-Id: <20200910070131.435543-7-philmd@redhat.com>
Signed-off-by: Laurent Vivier <laurent@vivier.eu>
Some QOM macros were using a X86_IOMMU_DEVICE prefix, and others
were using a X86_IOMMU prefix. Rename all of them to use the
same X86_IOMMU_DEVICE prefix.
This will make future conversion to OBJECT_DECLARE* easier.
Signed-off-by: Eduardo Habkost <ehabkost@redhat.com>
Message-Id: <20200825192110.3528606-47-ehabkost@redhat.com>
Acked-by: Peter Xu <peterx@redhat.com>
Signed-off-by: Eduardo Habkost <ehabkost@redhat.com>
HF2_GIF_MASK is set in env->hflags2 unconditionally on CPU reset
(see x86_cpu_reset()) but when calling KVM_SET_NESTED_STATE,
KVM_STATE_NESTED_GIF_SET is only valid for nSVM as e.g. nVMX code
looks like
if (kvm_state->hdr.vmx.vmxon_pa == -1ull) {
if (kvm_state->flags & ~KVM_STATE_NESTED_EVMCS)
return -EINVAL;
}
Also, when adjusting the environment after KVM_GET_NESTED_STATE we
need not reset HF2_GIF_MASK on VMX as e.g. x86_cpu_pending_interrupt()
expects it to be set.
Alternatively, we could've made env->hflags2 SVM-only.
Reported-by: Jan Kiszka <jan.kiszka@siemens.com>
Fixes: b16c0e20c7 ("KVM: add support for AMD nested live migration")
Signed-off-by: Vitaly Kuznetsov <vkuznets@redhat.com>
Message-Id: <20200723142701.2521161-1-vkuznets@redhat.com>
Tested-by: Jan Kiszka <jan.kiszka@siemens.com>
Signed-off-by: Eduardo Habkost <ehabkost@redhat.com>
Currently, QEMU is overriding KVM_GET_SUPPORTED_CPUID's answer for
the WAITPKG bit depending on the "-overcommit cpu-pm" setting. This is a
bad idea because it does not even check if the host supports it, but it
can be done in x86_cpu_realizefn just like we do for the MONITOR bit.
This patch moves it there, while making it conditional on host
support for the related UMWAIT MSR.
Cc: qemu-stable@nongnu.org
Reported-by: Maxim Levitsky <mlevitsk@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Support for nested guest live migration is part of Linux 5.8, add the
corresponding code to QEMU. The migration format consists of a few
flags, is an opaque 4k blob.
The blob is in VMCB format (the control area represents the L1 VMCB
control fields, the save area represents the pre-vmentry state; KVM does
not use the host save area since the AMD manual allows that) but QEMU
does not really care about that. However, the flags need to be
copied to hflags/hflags2 and back.
In addition, support for retrieving and setting the AMD nested virtualization
states allows the L1 guest to be reset while running a nested guest, but
a small bug in CPU reset needs to be fixed for that to work.
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
The Linux TSC calibration procedure is subject to small variations
(its common to see +-1 kHz difference between reboots on a given CPU, for example).
So migrating a guest between two hosts with identical processor can fail, in case
of a small variation in calibrated TSC between them.
Allow a conservative 250ppm error between host TSC and VM TSC frequencies,
rather than requiring an exact match. NTP daemon in the guest can
correct this difference.
Also change migration to accept this bound.
KVM_SET_TSC_KHZ depends on a kernel interface change. Without this change,
the behaviour remains the same: in case of a different frequency
between host and VM, KVM_SET_TSC_KHZ will fail and QEMU will exit.
Signed-off-by: Marcelo Tosatti <mtosatti@redhat.com>
Message-Id: <20200616165805.GA324612@fuller.cnet>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
The Perfmon and Debug Capability MSR named IA32_PERF_CAPABILITIES is
a feature-enumerating MSR, which only enumerates the feature full-width
write (via bit 13) by now which indicates the processor supports IA32_A_PMCx
interface for updating bits 32 and above of IA32_PMCx.
The existence of MSR IA32_PERF_CAPABILITIES is enumerated by CPUID.1:ECX[15].
Cc: Paolo Bonzini <pbonzini@redhat.com>
Cc: Richard Henderson <rth@twiddle.net>
Cc: Eduardo Habkost <ehabkost@redhat.com>
Cc: Marcelo Tosatti <mtosatti@redhat.com>
Cc: qemu-devel@nongnu.org
Signed-off-by: Like Xu <like.xu@linux.intel.com>
Message-Id: <20200529074347.124619-5-like.xu@linux.intel.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
When we hotplug vcpus, cpu_update_state is added to vm_change_state_head
in kvm_arch_init_vcpu(). But it forgot to delete in kvm_arch_destroy_vcpu() after
unplug. Then it will cause a use-after-free access. This patch delete it in
kvm_arch_destroy_vcpu() to fix that.
Reproducer:
virsh setvcpus vm1 4 --live
virsh setvcpus vm1 2 --live
virsh suspend vm1
virsh resume vm1
The UAF stack:
==qemu-system-x86_64==28233==ERROR: AddressSanitizer: heap-use-after-free on address 0x62e00002e798 at pc 0x5573c6917d9e bp 0x7fff07139e50 sp 0x7fff07139e40
WRITE of size 1 at 0x62e00002e798 thread T0
#0 0x5573c6917d9d in cpu_update_state /mnt/sdb/qemu/target/i386/kvm.c:742
#1 0x5573c699121a in vm_state_notify /mnt/sdb/qemu/vl.c:1290
#2 0x5573c636287e in vm_prepare_start /mnt/sdb/qemu/cpus.c:2144
#3 0x5573c6362927 in vm_start /mnt/sdb/qemu/cpus.c:2150
#4 0x5573c71e8304 in qmp_cont /mnt/sdb/qemu/monitor/qmp-cmds.c:173
#5 0x5573c727cb1e in qmp_marshal_cont qapi/qapi-commands-misc.c:835
#6 0x5573c7694c7a in do_qmp_dispatch /mnt/sdb/qemu/qapi/qmp-dispatch.c:132
#7 0x5573c7694c7a in qmp_dispatch /mnt/sdb/qemu/qapi/qmp-dispatch.c:175
#8 0x5573c71d9110 in monitor_qmp_dispatch /mnt/sdb/qemu/monitor/qmp.c:145
#9 0x5573c71dad4f in monitor_qmp_bh_dispatcher /mnt/sdb/qemu/monitor/qmp.c:234
Reported-by: Euler Robot <euler.robot@huawei.com>
Signed-off-by: Pan Nengyuan <pannengyuan@huawei.com>
Reviewed-by: Philippe Mathieu-Daudé <philmd@redhat.com>
Message-Id: <20200513132630.13412-1-pannengyuan@huawei.com>
Reviewed-by: Igor Mammedov <imammedo@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
No functional change.
This information will be used by following patches.
Reviewed-by: Nikita Leshenko <nikita.leshchenko@oracle.com>
Signed-off-by: Liran Alon <liran.alon@oracle.com>
Message-Id: <20200312165431.82118-15-liran.alon@oracle.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
kvm_hwpoison_page_add() and kvm_unpoison_all() will both
be used by X86 and ARM platforms, so moving them into
"accel/kvm/kvm-all.c" to avoid duplicate code.
For architectures that don't use the poison-list functionality
the reset handler will harmlessly do nothing, so let's register
the kvm_unpoison_all() function in the generic kvm_init() function.
Reviewed-by: Peter Maydell <peter.maydell@linaro.org>
Signed-off-by: Dongjiu Geng <gengdongjiu@huawei.com>
Signed-off-by: Xiang Zheng <zhengxiang9@huawei.com>
Acked-by: Xiang Zheng <zhengxiang9@huawei.com>
Message-id: 20200512030609.19593-8-gengdongjiu@huawei.com
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Commit 048c95163b ("target/i386: work around KVM_GET_MSRS bug for
secondary execution controls") added a workaround for KVM pre-dating
commit 6defc591846d ("KVM: nVMX: include conditional controls in /dev/kvm
KVM_GET_MSRS") which wasn't setting certain available controls. The
workaround uses generic CPUID feature bits to set missing VMX controls.
It was found that in some cases it is possible to observe hosts which
have certain CPUID features but lack the corresponding VMX control.
In particular, it was reported that Azure VMs have RDSEED but lack
VMX_SECONDARY_EXEC_RDSEED_EXITING; attempts to enable this feature
bit result in QEMU abort.
Resolve the issue but not applying the workaround when we don't have
to. As there is no good way to find out if KVM has the fix itself, use
95c5c7c77c ("KVM: nVMX: list VMX MSRs in KVM_GET_MSR_INDEX_LIST") instead
as these [are supposed to] come together.
Fixes: 048c95163b ("target/i386: work around KVM_GET_MSRS bug for secondary execution controls")
Suggested-by: Paolo Bonzini <pbonzini@redhat.com>
Signed-off-by: Vitaly Kuznetsov <vkuznets@redhat.com>
Message-Id: <20200331162752.1209928-1-vkuznets@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Even though MSR_IA32_UCODE_REV has been available long before Linux 5.6,
which added it to the emulated MSR list, a bug caused the microcode
version to revert to 0x100000000 on INIT. As a result, processors other
than the bootstrap processor would not see the host microcode revision;
some Windows version complain loudly about this and crash with a
fairly explicit MICROCODE REVISION MISMATCH error.
[If running 5.6 prereleases, the kernel fix "KVM: x86: do not reset
microcode version on INIT or RESET" should also be applied.]
Reported-by: Alex Williamson <alex.williamson@redhat.com>
Message-id: <20200211175516.10716-1-pbonzini@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
We actually want to access the accelerator, not the machine, so
use the current_accel() wrapper instead.
Suggested-by: Paolo Bonzini <pbonzini@redhat.com>
Reviewed-by: Alistair Francis <alistair.francis@wdc.com>
Signed-off-by: Philippe Mathieu-Daudé <philmd@redhat.com>
Message-Id: <20200121110349.25842-10-philmd@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
KVM can return the host microcode revision as a feature MSR.
Use it as the default value for -cpu host.
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Message-Id: <1579544504-3616-4-git-send-email-pbonzini@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Some read-only MSRs affect the behavior of ioctls such as
KVM_SET_NESTED_STATE. We can initialize them once and for all
right after the CPU is realized, since they will never be modified
by the guest.
Reported-by: Qingua Cheng <qcheng@redhat.com>
Cc: qemu-stable@nongnu.org
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Message-Id: <1579544504-3616-2-git-send-email-pbonzini@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
In ed9e923c3c ("x86: move SMM property to X86MachineState", 2019-12-17)
In v4.2.0-246-ged9e923c3c the SMM property was moved from PC
machine class to x86 machine class. Makes sense, but the change
was too aggressive: in target/i386/kvm.c:kvm_arch_init() it
altered check which sets SMRAM if given machine has SMM enabled.
The line that detects whether given machine object is class of
PC_MACHINE was removed from the check. This makes qemu try to
enable SMRAM for all machine types, which is not what we want.
Signed-off-by: Michal Privoznik <mprivozn@redhat.com>
Fixes: ed9e923c3c ("x86: move SMM property to X86MachineState", 2019-12-17)
Reviewed-by: Philippe Mathieu-Daudé <philmd@redhat.com>
Message-Id: <7cc91bab3191bfd7e071bdd3fdf7fe2a2991deb0.1577692822.git.mprivozn@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Legacy PCI device assignment has been already removed in commit ab37bfc7d6
("pci-assign: Remove"), but some codes remain unused.
CC: qemu-trivial@nongnu.org
Signed-off-by: Eiichi Tsukata <devel@etsukata.com>
Message-Id: <20191209072932.313056-1-devel@etsukata.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
These are needed by microvm too, so move them outside of PC-specific files.
With this patch, microvm.c need not include pc.h anymore.
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Add it to microvm as well, it is a generic property of the x86
architecture.
Suggested-by: Sergio Lopez <slp@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
The KVMState struct is opaque, so provide accessors for the fields
that will be moved from current_machine to the accelerator. For now
they just forward to the machine object, but this will change.
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
If kvm does not support VMX feature by nested=0, the kvm_vmx_basic
can't get the right value from MSR_IA32_VMX_BASIC register, which
make qemu coredump when qemu do KVM_SET_MSRS.
The coredump info:
error: failed to set MSR 0x480 to 0x0
kvm_put_msrs: Assertion `ret == cpu->kvm_msr_buf->nmsrs' failed.
Signed-off-by: Yang Zhong <yang.zhong@intel.com>
Message-Id: <20191206071111.12128-1-yang.zhong@intel.com>
Reported-by: Catherine Ho <catherine.hecx@gmail.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
The MSR_IA32_TSX_CTRL MSR can be used to hide TSX (also known as the
Trusty Side-channel Extension). By virtualizing the MSR, KVM guests
can disable TSX and avoid paying the price of mitigating TSX-based
attacks on microarchitectural side channels.
Reviewed-by: Eduardo Habkost <ehabkost@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
UMWAIT and TPAUSE instructions use 32bits IA32_UMWAIT_CONTROL at MSR
index E1H to determines the maximum time in TSC-quanta that the processor
can reside in either C0.1 or C0.2.
This patch is to Add support for save/load IA32_UMWAIT_CONTROL MSR in
guest.
Co-developed-by: Jingqi Liu <jingqi.liu@intel.com>
Signed-off-by: Jingqi Liu <jingqi.liu@intel.com>
Signed-off-by: Tao Xu <tao3.xu@intel.com>
Message-Id: <20191011074103.30393-3-tao3.xu@intel.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
UMONITOR, UMWAIT and TPAUSE are a set of user wait instructions.
This patch adds support for user wait instructions in KVM. Availability
of the user wait instructions is indicated by the presence of the CPUID
feature flag WAITPKG CPUID.0x07.0x0:ECX[5]. User wait instructions may
be executed at any privilege level, and use IA32_UMWAIT_CONTROL MSR to
set the maximum time.
The patch enable the umonitor, umwait and tpause features in KVM.
Because umwait and tpause can put a (psysical) CPU into a power saving
state, by default we dont't expose it to kvm and enable it only when
guest CPUID has it. And use QEMU command-line "-overcommit cpu-pm=on"
(enable_cpu_pm is enabled), a VM can use UMONITOR, UMWAIT and TPAUSE
instructions. If the instruction causes a delay, the amount of time
delayed is called here the physical delay. The physical delay is first
computed by determining the virtual delay (the time to delay relative to
the VM’s timestamp counter). Otherwise, UMONITOR, UMWAIT and TPAUSE cause
an invalid-opcode exception(#UD).
The release document ref below link:
https://software.intel.com/sites/default/files/\
managed/39/c5/325462-sdm-vol-1-2abcd-3abcd.pdf
Co-developed-by: Jingqi Liu <jingqi.liu@intel.com>
Signed-off-by: Jingqi Liu <jingqi.liu@intel.com>
Signed-off-by: Tao Xu <tao3.xu@intel.com>
Message-Id: <20191011074103.30393-2-tao3.xu@intel.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Hyper-V TLFS specifies this enlightenment as:
"NoNonArchitecturalCoreSharing - Indicates that a virtual processor will never
share a physical core with another virtual processor, except for virtual
processors that are reported as sibling SMT threads. This can be used as an
optimization to avoid the performance overhead of STIBP".
However, STIBP is not the only implication. It was found that Hyper-V on
KVM doesn't pass MD_CLEAR bit to its guests if it doesn't see
NoNonArchitecturalCoreSharing bit.
KVM reports NoNonArchitecturalCoreSharing in KVM_GET_SUPPORTED_HV_CPUID to
indicate that SMT on the host is impossible (not supported of forcefully
disabled).
Implement NoNonArchitecturalCoreSharing support in QEMU as tristate:
'off' - the feature is disabled (default)
'on' - the feature is enabled. This is only safe if vCPUS are properly
pinned and correct topology is exposed. As CPU pinning is done outside
of QEMU the enablement decision will be made on a higher level.
'auto' - copy KVM setting. As during live migration SMT settings on the
source and destination host may differ this requires us to add a migration
blocker.
Signed-off-by: Vitaly Kuznetsov <vkuznets@redhat.com>
Message-Id: <20191018163908.10246-1-vkuznets@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Patch logs MCE AO, AR messages injected to guest or taken by QEMU itself.
We print the QEMU address for guest MCEs, helps on hypervisors that have
another source of MCE logging like mce log, and when they go missing.
For example we found these QEMU logs:
September 26th 2019, 17:36:02.309 Droplet-153258224: Guest MCE Memory Error at qemu addr 0x7f8ce14f5000 and guest 3d6f5000 addr of type BUS_MCEERR_AR injected qemu-system-x86_64 amsN ams3nodeNNNN
September 27th 2019, 06:25:03.234 Droplet-153258224: Guest MCE Memory Error at qemu addr 0x7f8ce14f5000 and guest 3d6f5000 addr of type BUS_MCEERR_AR injected qemu-system-x86_64 amsN ams3nodeNNNN
The first log had a corresponding mce log entry, the second didnt (logging
thresholds) we can infer from second entry same PA and mce type.
Signed-off-by: Mario Smarduch <msmarduch@digitalocean.com>
Message-Id: <20191009164459.8209-3-msmarduch@digitalocean.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
KVM has a 80-entry limit at KVM_SET_CPUID2. With the
introduction of CPUID[0x1F], it is now possible to hit this limit
with unusual CPU configurations, e.g.:
$ ./x86_64-softmmu/qemu-system-x86_64 \
-smp 1,dies=2,maxcpus=2 \
-cpu EPYC,check=off,enforce=off \
-machine accel=kvm
qemu-system-x86_64: kvm_init_vcpu failed: Argument list too long
This happens because QEMU adds a lot of all-zeroes CPUID entries
for unused CPUID leaves. In the example above, we end up
creating 48 all-zeroes CPUID entries.
KVM already returns all-zeroes when emulating the CPUID
instruction if an entry is missing, so the all-zeroes entries are
redundant. Skip those entries. This reduces the CPUID table
size by half while keeping CPUID output unchanged.
Reported-by: Yumei Huang <yuhuang@redhat.com>
Fixes: https://bugzilla.redhat.com/show_bug.cgi?id=1741508
Signed-off-by: Eduardo Habkost <ehabkost@redhat.com>
Message-Id: <20190822225210.32541-1-ehabkost@redhat.com>
Acked-by: Paolo Bonzini <pbonzini@redhat.com>
Signed-off-by: Eduardo Habkost <ehabkost@redhat.com>
When I run QEMU with KVM under Valgrind, I currently get this warning:
Syscall param ioctl(generic) points to uninitialised byte(s)
at 0x95BA45B: ioctl (in /usr/lib64/libc-2.28.so)
by 0x429DC3: kvm_ioctl (kvm-all.c:2365)
by 0x51B249: kvm_arch_get_supported_msr_feature (kvm.c:469)
by 0x4C2A49: x86_cpu_get_supported_feature_word (cpu.c:3765)
by 0x4C4116: x86_cpu_expand_features (cpu.c:5065)
by 0x4C7F8D: x86_cpu_realizefn (cpu.c:5242)
by 0x5961F3: device_set_realized (qdev.c:835)
by 0x7038F6: property_set_bool (object.c:2080)
by 0x707EFE: object_property_set_qobject (qom-qobject.c:26)
by 0x705814: object_property_set_bool (object.c:1338)
by 0x498435: pc_new_cpu (pc.c:1549)
by 0x49C67D: pc_cpus_init (pc.c:1681)
Address 0x1ffeffee74 is on thread 1's stack
in frame #2, created by kvm_arch_get_supported_msr_feature (kvm.c:445)
It's harmless, but a little bit annoying, so silence it by properly
initializing the whole structure with zeroes.
Signed-off-by: Thomas Huth <thuth@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Some secondary controls are automatically enabled/disabled based on the CPUID
values that are set for the guest. However, they are still available at a
global level and therefore should be present when KVM_GET_MSRS is sent to
/dev/kvm.
Unfortunately KVM forgot to include those, so fix that.
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Add code to convert the VMX feature words back into MSR values,
allowing the user to enable/disable VMX features as they wish. The same
infrastructure enables support for limiting VMX features in named
CPU models.
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
VMX requires 64-bit feature words for the IA32_VMX_EPT_VPID_CAP
and IA32_VMX_BASIC MSRs. (The VMX control MSRs are 64-bit wide but
actually have only 32 bits of information).
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Suggested-by: Samuel Ortiz <sameo@linux.intel.com>
Reviewed-by: Li Qiang <liq3ea@gmail.com>
Signed-off-by: Philippe Mathieu-Daudé <philmd@redhat.com>
Message-Id: <20190818225414.22590-3-philmd@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Allow guest reads CORE cstate when exposing host CPU power management capabilities
to the guest. PKG cstate is restricted to avoid a guest to get the whole package
information in multi-tenant scenario.
Cc: Eduardo Habkost <ehabkost@redhat.com>
Cc: Paolo Bonzini <pbonzini@redhat.com>
Cc: Radim Krčmář <rkrcmar@redhat.com>
Signed-off-by: Wanpeng Li <wanpengli@tencent.com>
Message-Id: <1563154124-18579-1-git-send-email-wanpengli@tencent.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Intel CooperLake cpu adds AVX512_BF16 instruction, defining as
CPUID.(EAX=7,ECX=1):EAX[bit 05].
The patch adds a property for setting the subleaf of CPUID leaf 7 in
case that people would like to specify it.
The release spec link as follows,
https://software.intel.com/sites/default/files/managed/c5/15/\
architecture-instruction-set-extensions-programming-reference.pdf
Signed-off-by: Jing Liu <jing2.liu@linux.intel.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Not the whole structure is initialized before passing it to the KVM.
Reduce the number of Valgrind reports.
Signed-off-by: Andrey Shinkevich <andrey.shinkevich@virtuozzo.com>
Message-Id: <1564502498-805893-4-git-send-email-andrey.shinkevich@virtuozzo.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Function 'kvm_get_supported_msrs' is only called once
now, get rid of the static variable 'kvm_supported_msrs'.
Signed-off-by: Li Qiang <liq3ea@163.com>
Message-Id: <20190725151639.21693-1-liq3ea@163.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
