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: Paolo Bonzini <pbonzini@redhat.com>
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: Paolo Bonzini <pbonzini@redhat.com>
This patch reproduces for nSVM the change that was made for nVMX in
commit b5861e5cf2 ("KVM: nVMX: Fix loss of pending IRQ/NMI before
entering L2"). While I do not have a test that breaks without it, I
cannot see why it would not be necessary since all events are unblocked
by VMRUN's setting of GIF back to 1.
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
The current implementation of physical interrupt delivery to a nested guest
is quite broken. It relies on svm_interrupt_allowed returning false if
VINTR=1 so that the interrupt can be injected from enable_irq_window,
but this does not work for guests that do not intercept HLT or that rely
on clearing the host IF to block physical interrupts while L2 runs.
This patch can be split in two logical parts, but including only
one breaks tests so I am combining both changes together.
The first and easiest is simply to return true for svm_interrupt_allowed
if HF_VINTR_MASK is set and HIF is set. This way the semantics of
svm_interrupt_allowed are respected: svm_interrupt_allowed being false
does not mean "call enable_irq_window", it means "interrupts cannot
be injected now".
After doing this, however, we need another place to inject the
interrupt, and fortunately we already have one, check_nested_events,
which nested SVM does not implement but which is meant exactly for this
purpose. It is called before interrupts are injected, and it can
therefore do the L2->L1 switch while leaving inject_pending_event
none the wiser.
This patch was developed together with Cathy Avery, who wrote the
test and did a lot of the initial debugging.
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
If a nested VM is started while an IRQ was pending and with
V_INTR_MASKING=1, the behavior of the guest depends on host IF. If it
is 1, the VM should exit immediately, before executing the first
instruction of the guest, because VMRUN sets GIF back to 1.
If it is 0 and the host has VGIF, however, at the time of the VMRUN
instruction L0 is running the guest with a pending interrupt window
request. This interrupt window request is completely irrelevant to
L2, since IF only controls virtual interrupts, so this patch drops
INTERCEPT_VINTR from the VMCB while running L2 under these circumstances.
To simplify the code, both steps of enabling the interrupt window
(setting the VINTR intercept and requesting a fake virtual interrupt
in svm_inject_irq) are grouped in the svm_set_vintr function, and
likewise for dismissing the interrupt window request in svm_clear_vintr.
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Instead of touching the host intercepts so that the bitwise OR in
recalc_intercepts just works, mask away uninteresting intercepts
directly in recalc_intercepts.
This is cleaner and keeps the logic in one place even for intercepts
that can change even while L2 is running.
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
The set_cr3 callback is not setting the guest CR3, it is setting the
root of the guest page tables, either shadow or two-dimensional.
To make this clearer as well as to indicate that the MMU calls it
via kvm_mmu_load_cr3, rename it to load_mmu_pgd.
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Similar to what kvm-intel.ko is doing, provide a single callback that
merges svm_set_cr3, set_tdp_cr3 and nested_svm_set_tdp_cr3.
This lets us unify the set_cr3 and set_tdp_cr3 entries in kvm_x86_ops.
I'm doing that in this same patch because splitting it adds quite a bit
of churn due to the need for forward declarations. For the same reason
the assignment to vcpu->arch.mmu->set_cr3 is moved to kvm_init_shadow_mmu
from init_kvm_softmmu and nested_svm_init_mmu_context.
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Invert and rename the kvm_cpuid() param that controls out-of-range logic
to better reflect the semantics of the affected callers, i.e. callers
that bypass the out-of-range logic do so because they are looking up an
exact guest CPUID entry, e.g. to query the maxphyaddr.
Similarly, rename kvm_cpuid()'s internal "found" to "exact" to clarify
that it tracks whether or not the exact requested leaf was found, as
opposed to any usable leaf being found.
No functional change intended.
Signed-off-by: Sean Christopherson <sean.j.christopherson@intel.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Current CPUID 0xd enumeration code does not support supervisor
states, because KVM only supports setting IA32_XSS to zero.
Change it instead to use a new variable supported_xss, to be
set from the hardware_setup callback which is in charge of CPU
capabilities.
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Handle CPUID 0x8000000A in the main switch in __do_cpuid_func() and drop
->set_supported_cpuid() now that both VMX and SVM implementations are
empty. Like leaf 0x14 (Intel PT) and leaf 0x8000001F (SEV), leaf
0x8000000A is is (obviously) vendor specific but can be queried in
common code while respecting SVM's wishes by querying kvm_cpu_cap_has().
Suggested-by: Vitaly Kuznetsov <vkuznets@redhat.com>
Signed-off-by: Sean Christopherson <sean.j.christopherson@intel.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Set NRIPS in KVM capabilities if and only if nrips=true, which naturally
incorporates the boot_cpu_has() check, and set nrips_enabled only if the
KVM capability is enabled.
Note, previously KVM would set nrips_enabled based purely on userspace
input, but at worst that would cause KVM to propagate garbage into L1,
i.e. userspace would simply be hosing its VM.
Signed-off-by: Sean Christopherson <sean.j.christopherson@intel.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Set SVM feature bits in KVM capabilities if and only if nested=true, KVM
shouldn't advertise features that realistically can't be used. Use
kvm_cpu_cap_has(X86_FEATURE_SVM) to indirectly query "nested" in
svm_set_supported_cpuid() in anticipation of moving CPUID 0x8000000A
adjustments into common x86 code.
Suggested-by: Paolo Bonzini <pbonzini@redhat.com>
Signed-off-by: Sean Christopherson <sean.j.christopherson@intel.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Configure the max page level during hardware setup to avoid a retpoline
in the page fault handler. Drop ->get_lpage_level() as the page fault
handler was the last user.
No functional change intended.
Reviewed-by: Vitaly Kuznetsov <vkuznets@redhat.com>
Signed-off-by: Sean Christopherson <sean.j.christopherson@intel.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Combine kvm_enable_tdp() and kvm_disable_tdp() into a single function,
kvm_configure_mmu(), in preparation for doing additional configuration
during hardware setup. And because having separate helpers is silly.
No functional change intended.
Reviewed-by: Vitaly Kuznetsov <vkuznets@redhat.com>
Signed-off-by: Sean Christopherson <sean.j.christopherson@intel.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Tweak SVM's logging of NPT enabled/disabled to handle the logging in a
single pr_info() in preparation for merging kvm_enable_tdp() and
kvm_disable_tdp() into a single function.
No functional change intended.
Reviewed-by: Vitaly Kuznetsov <vkuznets@redhat.com>
Signed-off-by: Sean Christopherson <sean.j.christopherson@intel.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Use vmx_pt_mode_is_host_guest() in intel_pmu_refresh() instead of
bouncing through kvm_x86_ops->pt_supported, and remove ->pt_supported()
as the PMU code was the last remaining user.
Opportunistically clean up the wording of a comment that referenced
kvm_x86_ops->pt_supported().
No functional change intended.
Reviewed-by: Vitaly Kuznetsov <vkuznets@redhat.com>
Signed-off-by: Sean Christopherson <sean.j.christopherson@intel.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Check for MSR_TSC_AUX virtualization via kvm_cpu_cap_has() and drop
->rdtscp_supported().
Note, vmx_rdtscp_supported() needs to hang around a tiny bit longer due
other usage in VMX code.
No functional change intended.
Reviewed-by: Vitaly Kuznetsov <vkuznets@redhat.com>
Signed-off-by: Sean Christopherson <sean.j.christopherson@intel.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Set emulated and transmuted (set based on other features) feature bits
via kvm_cpu_caps now that the CPUID output for KVM_GET_SUPPORTED_CPUID
is direcly overidden with kvm_cpu_caps.
Note, VMX emulation of UMIP already sets kvm_cpu_caps.
No functional change intended.
Reviewed-by: Vitaly Kuznetsov <vkuznets@redhat.com>
Signed-off-by: Sean Christopherson <sean.j.christopherson@intel.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Override CPUID entries with kvm_cpu_caps during KVM_GET_SUPPORTED_CPUID
instead of masking the host CPUID result, which is redundant now that
the host CPUID is incorporated into kvm_cpu_caps at runtime.
No functional change intended.
Reviewed-by: Vitaly Kuznetsov <vkuznets@redhat.com>
Signed-off-by: Sean Christopherson <sean.j.christopherson@intel.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Set UMIP in kvm_cpu_caps when it is emulated by VMX, even though the
bit will effectively be dropped by do_host_cpuid(). This allows
checking for UMIP emulation via kvm_cpu_caps instead of a dedicated
kvm_x86_ops callback.
No functional change intended.
Reviewed-by: Vitaly Kuznetsov <vkuznets@redhat.com>
Signed-off-by: Sean Christopherson <sean.j.christopherson@intel.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Add a helper, kvm_cpu_cap_check_and_set(), to query boot_cpu_has() as
part of setting a KVM cpu capability. VMX in particular has a number of
features that are dependent on both a VMCS capability and kernel
support.
No functional change intended.
Reviewed-by: Vitaly Kuznetsov <vkuznets@redhat.com>
Signed-off-by: Sean Christopherson <sean.j.christopherson@intel.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Move the clearing of the XSAVES CPUID bit into VMX, which has a separate
VMCS control to enable XSAVES in non-root, to eliminate the last ugly
renmant of the undesirable "unsigned f_* = *_supported ? F(*) : 0"
pattern in the common CPUID handling code.
Drop ->xsaves_supported(), CPUID adjustment was the only user.
No functional change intended.
Reviewed-by: Vitaly Kuznetsov <vkuznets@redhat.com>
Signed-off-by: Sean Christopherson <sean.j.christopherson@intel.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Use the recently introduced KVM CPU caps to propagate SVM-only (kernel)
settings to supported CPUID flags.
Note, there are a few subtleties:
- Setting a flag based on a *different* feature is effectively
emulation, and must be done at runtime via ->set_supported_cpuid().
- CPUID 0x8000000A.EDX is a feature leaf that was previously not
adjusted by kvm_cpu_cap_mask() because all features are hidden by
default.
Opportunistically add a technically unnecessary break and fix an
indentation issue in svm_set_supported_cpuid().
No functional change intended.
Reviewed-by: Vitaly Kuznetsov <vkuznets@redhat.com>
Signed-off-by: Sean Christopherson <sean.j.christopherson@intel.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Calculate the CPUID masks for KVM_GET_SUPPORTED_CPUID at load time using
what is effectively a KVM-adjusted copy of boot_cpu_data, or more
precisely, the x86_capability array in boot_cpu_data.
In terms of KVM support, the vast majority of CPUID feature bits are
constant, and *all* feature support is known at KVM load time. Rather
than apply boot_cpu_data, which is effectively read-only after init,
at runtime, copy it into a KVM-specific array and use *that* to mask
CPUID registers.
In additional to consolidating the masking, kvm_cpu_caps can be adjusted
by SVM/VMX at load time and thus eliminate all feature bit manipulation
in ->set_supported_cpuid().
Opportunistically clean up a few warts:
- Replace bare "unsigned" with "unsigned int" when a feature flag is
captured in a local variable, e.g. f_nx.
- Sort the CPUID masks by function, index and register (alphabetically
for registers, i.e. EBX comes before ECX/EDX).
- Remove the superfluous /* cpuid 7.0.ecx */ comments.
No functional change intended.
Signed-off-by: Sean Christopherson <sean.j.christopherson@intel.com>
[Call kvm_set_cpu_caps from kvm_x86_ops->hardware_setup due to fixed
GBPAGES patch. - Paolo]
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Move the setting of the PKU CPUID bit into VMX to eliminate an instance
of the undesirable "unsigned f_* = *_supported ? F(*) : 0" pattern in
the common CPUID handling code. Drop ->pku_supported(), CPUID
adjustment was the only user.
Note, some AMD CPUs now support PKU, but SVM doesn't yet support
exposing it to a guest.
No functional change intended.
Reviewed-by: Vitaly Kuznetsov <vkuznets@redhat.com>
Signed-off-by: Sean Christopherson <sean.j.christopherson@intel.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Move the INVPCID CPUID adjustments into VMX to eliminate an instance of
the undesirable "unsigned f_* = *_supported ? F(*) : 0" pattern in the
common CPUID handling code. Drop ->invpcid_supported(), CPUID
adjustment was the only user.
No functional change intended.
Reviewed-by: Vitaly Kuznetsov <vkuznets@redhat.com>
Signed-off-by: Sean Christopherson <sean.j.christopherson@intel.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Introduce mutators to modify feature bits in CPUID entries and use the
new mutators where applicable. Using the mutators eliminates the need
to manually specify the register to modify query at no extra cost and
will allow adding runtime consistency checks on the function/index in a
future patch.
No functional change intended.
Reviewed-by: Vitaly Kuznetsov <vkuznets@redhat.com>
Signed-off-by: Sean Christopherson <sean.j.christopherson@intel.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Drop the explicit @func param from ->set_supported_cpuid() and instead
pull the CPUID function from the relevant entry. This sets the stage
for hardening guest CPUID updates in future patches, e.g. allows adding
run-time assertions that the CPUID feature being changed is actually
a bit in the referenced CPUID entry.
No functional change intended.
Reviewed-by: Vitaly Kuznetsov <vkuznets@redhat.com>
Signed-off-by: Sean Christopherson <sean.j.christopherson@intel.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Query supported_xcr0 when checking for MPX support instead of invoking
->mpx_supported() and drop ->mpx_supported() as kvm_mpx_supported() was
its last user. Rename vmx_mpx_supported() to cpu_has_vmx_mpx() to
better align with VMX/VMCS nomenclature.
Modify VMX's adjustment of xcr0 to call cpus_has_vmx_mpx() (renamed from
vmx_mpx_supported()) directly to avoid reading supported_xcr0 before
it's fully configured.
No functional change intended.
Reviewed-by: Xiaoyao Li <xiaoyao.li@intel.com>
Reviewed-by: Vitaly Kuznetsov <vkuznets@redhat.com>
Signed-off-by: Sean Christopherson <sean.j.christopherson@intel.com>
[Test that *all* bits are set. - Paolo]
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Add a new global variable, supported_xcr0, to track which xcr0 bits can
be exposed to the guest instead of calculating the mask on every call.
The supported bits are constant for a given instance of KVM.
This paves the way toward eliminating the ->mpx_supported() call in
kvm_mpx_supported(), e.g. eliminates multiple retpolines in VMX's nested
VM-Enter path, and eventually toward eliminating ->mpx_supported()
altogether.
No functional change intended.
Reviewed-by: Xiaoyao Li <xiaoyao.li@intel.com>
Reviewed-by: Vitaly Kuznetsov <vkuznets@redhat.com>
Signed-off-by: Sean Christopherson <sean.j.christopherson@intel.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Explicitly pass an exception struct when checking for intercept from
the emulator, which eliminates the last reference to arch.emulate_ctxt
in vendor specific code.
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>
Rename kvm_mmu->get_cr3() to call out that it is retrieving a guest
value, as opposed to kvm_mmu->set_cr3(), which sets a host value, and to
note that it will return something other than CR3 when nested EPT is in
use. Hopefully the new name will also make it more obvious that L1's
nested_cr3 is returned in SVM's nested NPT case.
No functional change intended.
Signed-off-by: Sean Christopherson <sean.j.christopherson@intel.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
The AVIC does not support guest use of the x2APIC interface. Currently,
KVM simply chooses to squash the x2APIC feature in the guest's CPUID
If the AVIC is enabled. Doing so prevents KVM from running a guest
with greater than 255 vCPUs, as such a guest necessitates the use
of the x2APIC interface.
Instead, inhibit AVIC enablement on a per-VM basis whenever the x2APIC
feature is set in the guest's CPUID.
Signed-off-by: Oliver Upton <oupton@google.com>
Reviewed-by: Jim Mattson <jmattson@google.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Move the VM allocation and free code to common x86 as the logic is
more or less identical across SVM and VMX.
Note, although hyperv.hv_pa_pg is part of the common kvm->arch, it's
(currently) only allocated by VMX VMs. But, since kfree() plays nice
when passed a NULL pointer, the superfluous call for SVM is harmless
and avoids future churn if SVM gains support for HyperV's direct TLB
flush.
Signed-off-by: Sean Christopherson <sean.j.christopherson@intel.com>
Reviewed-by: Vitaly Kuznetsov <vkuznets@redhat.com>
[Make vm_size a field instead of a function. - Paolo]
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Directly return the __vmalloc() result in {svm,vmx}_vm_alloc() to pave
the way for handling VM alloc/free in common x86 code, and to obviate
the need to check the result of __vmalloc() in vendor specific code.
Add a build-time assertion to ensure each structs' "kvm" field stays at
offset 0, which allows interpreting a "struct kvm_{svm,vmx}" as a
"struct kvm".
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>
Check the result of __vmalloc() to avoid dereferencing a NULL pointer in
the event that allocation failres.
Fixes: d1e5b0e98e ("kvm: Make VM ioctl do valloc for some archs")
Cc: stable@vger.kernel.org
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>
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>
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>
Since commit 5f3d45e7f2 ("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: 5f3d45e7f2 ("kvm/x86: add support for MONITOR_TRAP_FLAG")
Signed-off-by: Oliver Upton <oupton@google.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
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>
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>
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>
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: 8937d76239 ("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>
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>
Userspace that does not know about the AMD_IBRS bit might still
allow the guest to protect itself with MSR_IA32_SPEC_CTRL using
the Intel SPEC_CTRL bit. However, svm.c disallows this and will
cause a #GP in the guest when writing to the MSR. Fix this by
loosening the test and allowing the Intel CPUID bit, and in fact
allow the AMD_STIBP bit as well since it allows writing to
MSR_IA32_SPEC_CTRL too.
Reported-by: Zhiyi Guo <zhguo@redhat.com>
Analyzed-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
Analyzed-by: Laszlo Ersek <lersek@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
SVM is now able to disable AVIC dynamically whenever the in-kernel PIT sets
up an ack notifier, so we can enable it even if in-kernel IOAPIC/PIC/PIT
are in use.
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
AMD SVM AVIC accelerates EOI write and does not trap. This causes
in-kernel PIT re-injection mode to fail since it relies on irq-ack
notifier mechanism. So, APICv is activated only when in-kernel PIT
is in discard mode e.g. w/ qemu option:
-global kvm-pit.lost_tick_policy=discard
Also, introduce APICV_INHIBIT_REASON_PIT_REINJ bit to be used for this
reason.
Suggested-by: Paolo Bonzini <pbonzini@redhat.com>
Signed-off-by: Suravee Suthikulpanit <suravee.suthikulpanit@amd.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>