Pull x86 fixes from Borislav Petkov:
- Fix a couple of SWAPGS fencing issues in the x86 entry code
- Use the proper operand types in __{get,put}_user() to prevent
truncation in SEV-ES string io
- Make sure the kernel mappings are present in trampoline_pgd in order
to prevent any potential accesses to unmapped memory after switching
to it
- Fix a trivial list corruption in objtool's pv_ops validation
- Disable the clocksource watchdog for TSC on platforms which claim
that the TSC is constant, doesn't stop in sleep states, CPU has TSC
adjust and the number of sockets of the platform are max 2, to
prevent erroneous markings of the TSC as unstable.
- Make sure TSC adjust is always checked not only when going idle
- Prevent a stack leak by initializing struct _fpx_sw_bytes properly in
the FPU code
- Fix INTEL_FAM6_RAPTORLAKE define naming to adhere to the convention
* tag 'x86_urgent_for_v5.16_rc4' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
x86/xen: Add xenpv_restore_regs_and_return_to_usermode()
x86/entry: Use the correct fence macro after swapgs in kernel CR3
x86/entry: Add a fence for kernel entry SWAPGS in paranoid_entry()
x86/sev: Fix SEV-ES INS/OUTS instructions for word, dword, and qword
x86/64/mm: Map all kernel memory into trampoline_pgd
objtool: Fix pv_ops noinstr validation
x86/tsc: Disable clocksource watchdog for TSC on qualified platorms
x86/tsc: Add a timer to make sure TSC_adjust is always checked
x86/fpu/signal: Initialize sw_bytes in save_xstate_epilog()
x86/cpu: Drop spurious underscore from RAPTOR_LAKE #define
Pull more kvm fixes from Paolo Bonzini:
- Static analysis fix
- New SEV-ES protocol for communicating invalid VMGEXIT requests
- Ensure APICv is considered inactive if there is no APIC
- Fix reserved bits for AMD PerfEvtSeln register
* tag 'for-linus' of git://git.kernel.org/pub/scm/virt/kvm/kvm:
KVM: SVM: Do not terminate SEV-ES guests on GHCB validation failure
KVM: SEV: Fall back to vmalloc for SEV-ES scratch area if necessary
KVM: SEV: Return appropriate error codes if SEV-ES scratch setup fails
KVM: x86/mmu: Retry page fault if root is invalidated by memslot update
KVM: VMX: Set failure code in prepare_vmcs02()
KVM: ensure APICv is considered inactive if there is no APIC
KVM: x86/pmu: Fix reserved bits for AMD PerfEvtSeln register
Currently, an SEV-ES guest is terminated if the validation of the VMGEXIT
exit code or exit parameters fails.
The VMGEXIT instruction can be issued from userspace, even though
userspace (likely) can't update the GHCB. To prevent userspace from being
able to kill the guest, return an error through the GHCB when validation
fails rather than terminating the guest. For cases where the GHCB can't be
updated (e.g. the GHCB can't be mapped, etc.), just return back to the
guest.
The new error codes are documented in the lasest update to the GHCB
specification.
Fixes: 291bd20d5d ("KVM: SVM: Add initial support for a VMGEXIT VMEXIT")
Signed-off-by: Tom Lendacky <thomas.lendacky@amd.com>
Message-Id: <b57280b5562893e2616257ac9c2d4525a9aeeb42.1638471124.git.thomas.lendacky@amd.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
In the following commit:
025768a966 x86/cpu: Use alternative to generate the TASK_SIZE_MAX constant
... we added the new task_size_max() inline, which uses X86_FEATURE_LA57,
but doesn't include <asm/cpufeatures.h> which defines the constant.
Due to the way alternatives macros work currently this doesn't get reported as an
immediate build error, only as a link error, if a .c file happens to include
<asm/page.h> first:
> ld: kernel/fork.o:(.altinstructions+0x98): undefined reference to `X86_FEATURE_LA57'
In the current upstream kernel no .c file includes <asm/page.h> before including
some other header that includes <asm/cpufeatures.h>, which is why this dependency
bug went unnoticed.
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Ingo Molnar <mingo@kernel.org>
kvm_vcpu_apicv_active() returns false if a virtual machine has no in-kernel
local APIC, however kvm_apicv_activated might still be true if there are
no reasons to disable APICv; in fact it is quite likely that there is none
because APICv is inhibited by specific configurations of the local APIC
and those configurations cannot be programmed. This triggers a WARN:
WARN_ON_ONCE(kvm_apicv_activated(vcpu->kvm) != kvm_vcpu_apicv_active(vcpu));
To avoid this, introduce another cause for APICv inhibition, namely the
absence of an in-kernel local APIC. This cause is enabled by default,
and is dropped by either KVM_CREATE_IRQCHIP or the enabling of
KVM_CAP_IRQCHIP_SPLIT.
Reported-by: Ignat Korchagin <ignat@cloudflare.com>
Fixes: ee49a89329 ("KVM: x86: Move SVM's APICv sanity check to common x86", 2021-10-22)
Reviewed-by: Maxim Levitsky <mlevitsk@redhat.com>
Reviewed-by: Sean Christopherson <seanjc@google.com>
Tested-by: Ignat Korchagin <ignat@cloudflare.com>
Message-Id: <20211130123746.293379-1-pbonzini@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
In preparation for sharing MMIO instruction decode between SEV-ES and
TDX, factor out the common decode into a new insn_decode_mmio() helper.
For regular virtual machine, MMIO is handled by the VMM and KVM
emulates instructions that caused MMIO. But, this model doesn't work
for a secure VMs (like SEV or TDX) as VMM doesn't have access to the
guest memory and register state. So, for TDX or SEV VMM needs
assistance in handling MMIO. It induces exception in the guest. Guest
has to decode the instruction and handle it on its own.
The code is based on the current SEV MMIO implementation.
Signed-off-by: Kirill A. Shutemov <kirill.shutemov@linux.intel.com>
Signed-off-by: Dave Hansen <dave.hansen@linux.intel.com>
Reviewed-by: Andi Kleen <ak@linux.intel.com>
Reviewed-by: Tony Luck <tony.luck@intel.com>
Tested-by: Joerg Roedel <jroedel@suse.de>
Acked-by: Tom Lendacky <thomas.lendacky@amd.com>
Link: https://lkml.kernel.org/r/20211130184933.31005-4-kirill.shutemov@linux.intel.com
Kernel fails to compile with PARAVIRT_XXL=y if XEN_PV is not enabled:
ld.lld: error: undefined symbol: xen_iret
It happens because INTERRUPT_RETURN defined to use xen_iret if
CONFIG_PARAVIRT_XXL enabled regardless of CONFIG_XEN_PV.
The issue is not visible in the current kernel because CONFIG_XEN_PV is
the only user of CONFIG_PARAVIRT_XXL and there's no way to enable them
separately.
Rework code to define INTERRUPT_RETURN based on CONFIG_XEN_PV, not
CONFIG_PARAVIRT_XXL.
Signed-off-by: Kirill A. Shutemov <kirill.shutemov@linux.intel.com>
Signed-off-by: Dave Hansen <dave.hansen@linux.intel.com>
Reviewed-by: Juergen Gross <jgross@suse.com>
Link: https://lkml.kernel.org/r/20211130185533.32658-1-kirill.shutemov@linux.intel.com
Pull xen fixes from Juergen Gross:
- Kconfig fix to make it possible to control building of the privcmd
driver
- three fixes for issues identified by the kernel test robot
- a five-patch series to simplify timeout handling for Xen PV driver
initialization
- two patches to fix error paths in xenstore/xenbus driver
initialization
* tag 'for-linus-5.16c-rc3-tag' of git://git.kernel.org/pub/scm/linux/kernel/git/xen/tip:
xen: make HYPERVISOR_set_debugreg() always_inline
xen: make HYPERVISOR_get_debugreg() always_inline
xen: detect uninitialized xenbus in xenbus_init
xen: flag xen_snd_front to be not essential for system boot
xen: flag pvcalls-front to be not essential for system boot
xen: flag hvc_xen to be not essential for system boot
xen: flag xen_drm_front to be not essential for system boot
xen: add "not_essential" flag to struct xenbus_driver
xen/pvh: add missing prototype to header
xen: don't continue xenstore initialization in case of errors
xen/privcmd: make option visible in Kconfig
Increase the number of arguments supported by mixed mode calls, so that
we will be able to call into the TCG2 protocol to measure the initrd
and extend the associated PCR. This involves the TCG2 protocol's
hash_log_extend_event() method, which takes five arguments, three of
which are u64 and need to be split, producing a total of 8 outgoing
Signed-off-by: Ard Biesheuvel <ardb@kernel.org>
Signed-off-by: Ilias Apalodimas <ilias.apalodimas@linaro.org>
Link: https://lore.kernel.org/r/20211119114745.1560453-3-ilias.apalodimas@linaro.org
Signed-off-by: Ard Biesheuvel <ardb@kernel.org>
Pull KVM fixes from Paolo Bonzini:
"Selftest changes:
- Cleanups for the perf test infrastructure and mapping hugepages
- Avoid contention on mmap_sem when the guests start to run
- Add event channel upcall support to xen_shinfo_test
x86 changes:
- Fixes for Xen emulation
- Kill kvm_map_gfn() / kvm_unmap_gfn() and broken gfn_to_pfn_cache
- Fixes for migration of 32-bit nested guests on 64-bit hypervisor
- Compilation fixes
- More SEV cleanups
Generic:
- Cap the return value of KVM_CAP_NR_VCPUS to both KVM_CAP_MAX_VCPUS
and num_online_cpus(). Most architectures were only using one of
the two"
* tag 'for-linus' of git://git.kernel.org/pub/scm/virt/kvm/kvm: (42 commits)
KVM: x86: Cap KVM_CAP_NR_VCPUS by KVM_CAP_MAX_VCPUS
KVM: s390: Cap KVM_CAP_NR_VCPUS by num_online_cpus()
KVM: RISC-V: Cap KVM_CAP_NR_VCPUS by KVM_CAP_MAX_VCPUS
KVM: PPC: Cap KVM_CAP_NR_VCPUS by KVM_CAP_MAX_VCPUS
KVM: MIPS: Cap KVM_CAP_NR_VCPUS by KVM_CAP_MAX_VCPUS
KVM: arm64: Cap KVM_CAP_NR_VCPUS by kvm_arm_default_max_vcpus()
KVM: x86: Assume a 64-bit hypercall for guests with protected state
selftests: KVM: Add /x86_64/sev_migrate_tests to .gitignore
riscv: kvm: fix non-kernel-doc comment block
KVM: SEV: Fix typo in and tweak name of cmd_allowed_from_miror()
KVM: SEV: Drop a redundant setting of sev->asid during initialization
KVM: SEV: WARN if SEV-ES is marked active but SEV is not
KVM: SEV: Set sev_info.active after initial checks in sev_guest_init()
KVM: SEV: Disallow COPY_ENC_CONTEXT_FROM if target has created vCPUs
KVM: Kill kvm_map_gfn() / kvm_unmap_gfn() and gfn_to_pfn_cache
KVM: nVMX: Use a gfn_to_hva_cache for vmptrld
KVM: nVMX: Use kvm_read_guest_offset_cached() for nested VMCS check
KVM: x86/xen: Use sizeof_field() instead of open-coding it
KVM: nVMX: Use kvm_{read,write}_guest_cached() for shadow_vmcs12
KVM: x86/xen: Fix get_attr of KVM_XEN_ATTR_TYPE_SHARED_INFO
...
* Fixes for Xen emulation
* Kill kvm_map_gfn() / kvm_unmap_gfn() and broken gfn_to_pfn_cache
* Fixes for migration of 32-bit nested guests on 64-bit hypervisor
* Compilation fixes
* More SEV cleanups
Incorporate EFER.LMA into kvm_mmu_extended_role, as it used to compute the
guest root level and is not reflected in kvm_mmu_page_role.level when TDP
is in use. When simply running the guest, it is impossible for EFER.LMA
and kvm_mmu.root_level to get out of sync, as the guest cannot transition
from PAE paging to 64-bit paging without toggling CR0.PG, i.e. without
first bouncing through a different MMU context. And stuffing guest state
via KVM_SET_SREGS{,2} also ensures a full MMU context reset.
However, if KVM_SET_SREGS{,2} is followed by KVM_SET_NESTED_STATE, e.g. to
set guest state when migrating the VM while L2 is active, the vCPU state
will reflect L2, not L1. If L1 is using TDP for L2, then root_mmu will
have been configured using L2's state, despite not being used for L2. If
L2.EFER.LMA != L1.EFER.LMA, and L2 is using PAE paging, then root_mmu will
be configured for guest PAE paging, but will match the mmu_role for 64-bit
paging and cause KVM to not reconfigure root_mmu on the next nested VM-Exit.
Alternatively, the root_mmu's role could be invalidated after a successful
KVM_SET_NESTED_STATE that yields vcpu->arch.mmu != vcpu->arch.root_mmu,
i.e. that switches the active mmu to guest_mmu, but doing so is unnecessarily
tricky, and not even needed if L1 and L2 do have the same role (e.g., they
are both 64-bit guests and run with the same CR4).
Suggested-by: Sean Christopherson <seanjc@google.com>
Signed-off-by: Maxim Levitsky <mlevitsk@redhat.com>
Message-Id: <20211115131837.195527-3-mlevitsk@redhat.com>
Cc: stable@vger.kernel.org
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Move x86's perf guest callbacks into common KVM, as they are semantically
identical to arm64's callbacks (the only other such KVM callbacks).
arm64 will convert to the common versions in a future patch.
Implement the necessary arm64 arch hooks now to avoid having to provide
stubs or a temporary #define (from x86) to avoid arm64 compilation errors
when CONFIG_GUEST_PERF_EVENTS=y.
Signed-off-by: Sean Christopherson <seanjc@google.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Reviewed-by: Paolo Bonzini <pbonzini@redhat.com>
Acked-by: Marc Zyngier <maz@kernel.org>
Link: https://lore.kernel.org/r/20211111020738.2512932-13-seanjc@google.com
Use the generic kvm_running_vcpu plus a new 'handling_intr_from_guest'
variable in kvm_arch_vcpu instead of the semi-redundant current_vcpu.
kvm_before/after_interrupt() must be called while the vCPU is loaded,
(which protects against preemption), thus kvm_running_vcpu is guaranteed
to be non-NULL when handling_intr_from_guest is non-zero.
Switching to kvm_get_running_vcpu() will allows moving KVM's perf
callbacks to generic code, and the new flag will be used in a future
patch to more precisely identify the "NMI from guest" case.
Signed-off-by: Sean Christopherson <seanjc@google.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Reviewed-by: Paolo Bonzini <pbonzini@redhat.com>
Link: https://lore.kernel.org/r/20211111020738.2512932-11-seanjc@google.com
To prepare for using static_calls to optimize perf's guest callbacks,
replace ->is_in_guest and ->is_user_mode with a new multiplexed hook
->state, tweak ->handle_intel_pt_intr to play nice with being called when
there is no active guest, and drop "guest" from ->get_guest_ip.
Return '0' from ->state and ->handle_intel_pt_intr to indicate "not in
guest" so that DEFINE_STATIC_CALL_RET0 can be used to define the static
calls, i.e. no callback == !guest.
[sean: extracted from static_call patch, fixed get_ip() bug, wrote changelog]
Suggested-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Originally-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Signed-off-by: Like Xu <like.xu@linux.intel.com>
Signed-off-by: Zhu Lingshan <lingshan.zhu@intel.com>
Signed-off-by: Sean Christopherson <seanjc@google.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Reviewed-by: Boris Ostrovsky <boris.ostrovsky@oracle.com>
Reviewed-by: Paolo Bonzini <pbonzini@redhat.com>
Link: https://lore.kernel.org/r/20211111020738.2512932-7-seanjc@google.com
Remove all the defines of masks and bit positions for the GHCB MSR
protocol and use comments instead which correspond directly to the spec
so that following those can be a lot easier and straightforward with the
spec opened in parallel to the code.
Aligh vertically while at it.
No functional changes.
Signed-off-by: Borislav Petkov <bp@suse.de>
Signed-off-by: Brijesh Singh <brijesh.singh@amd.com>
Signed-off-by: Borislav Petkov <bp@suse.de>
Link: https://lkml.kernel.org/r/20211110220731.2396491-6-brijesh.singh@amd.com
Add a call inside memory_failure() to call the arch specific code
to check if the address is an SGX EPC page and handle it.
Note the SGX EPC pages do not have a "struct page" entry, so the hook
goes in at the same point as the device mapping hook.
Pull the call to acquire the mutex earlier so the SGX errors are also
protected.
Make set_mce_nospec() skip SGX pages when trying to adjust
the 1:1 map.
Signed-off-by: Tony Luck <tony.luck@intel.com>
Signed-off-by: Dave Hansen <dave.hansen@linux.intel.com>
Reviewed-by: Jarkko Sakkinen <jarkko@kernel.org>
Reviewed-by: Naoya Horiguchi <naoya.horiguchi@nec.com>
Tested-by: Reinette Chatre <reinette.chatre@intel.com>
Link: https://lkml.kernel.org/r/20211026220050.697075-6-tony.luck@intel.com
Pull x86 static call update from Thomas Gleixner:
"A single fix for static calls to make the trampoline patching more
robust by placing explicit signature bytes after the call trampoline
to prevent patching random other jumps like the CFI jump table
entries"
* tag 'locking-urgent-2021-11-14' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
static_call,x86: Robustify trampoline patching
Pull scheduler fixes from Borislav Petkov:
- Avoid touching ~100 config files in order to be able to select the
preemption model
- clear cluster CPU masks too, on the CPU unplug path
- prevent use-after-free in cfs
- Prevent a race condition when updating CPU cache domains
- Factor out common shared part of smp_prepare_cpus() into a common
helper which can be called by both baremetal and Xen, in order to fix
a booting of Xen PV guests
* tag 'sched_urgent_for_v5.16_rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
preempt: Restore preemption model selection configs
arch_topology: Fix missing clear cluster_cpumask in remove_cpu_topology()
sched/fair: Prevent dead task groups from regaining cfs_rq's
sched/core: Mitigate race cpus_share_cache()/update_top_cache_domain()
x86/smp: Factor out parts of native_smp_prepare_cpus()
Pull x86 fixes from Borislav Petkov:
- Add the model number of a new, Raptor Lake CPU, to intel-family.h
- Do not log spurious corrected MCEs on SKL too, due to an erratum
- Clarify the path of paravirt ops patches upstream
- Add an optimization to avoid writing out AMX components to sigframes
when former are in init state
* tag 'x86_urgent_for_v5.16_rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
x86/cpu: Add Raptor Lake to Intel family
x86/mce: Add errata workaround for Skylake SKX37
MAINTAINERS: Add some information to PARAVIRT_OPS entry
x86/fpu: Optimize out sigframe xfeatures when in init state
* Fix misuse of gfn-to-pfn cache when recording guest steal time / preempted status
* Fix selftests on APICv machines
* Fix sparse warnings
* Fix detection of KVM features in CPUID
* Cleanups for bogus writes to MSR_KVM_PV_EOI_EN
* Fixes and cleanups for MSR bitmap handling
* Cleanups for INVPCID
* Make x86 KVM_SOFT_MAX_VCPUS consistent with other architectures
Add support for AMD SEV and SEV-ES intra-host migration support. Intra
host migration provides a low-cost mechanism for userspace VMM upgrades.
In the common case for intra host migration, we can rely on the normal
ioctls for passing data from one VMM to the next. SEV, SEV-ES, and other
confidential compute environments make most of this information opaque, and
render KVM ioctls such as "KVM_GET_REGS" irrelevant. As a result, we need
the ability to pass this opaque metadata from one VMM to the next. The
easiest way to do this is to leave this data in the kernel, and transfer
ownership of the metadata from one KVM VM (or vCPU) to the next. In-kernel
hand off makes it possible to move any data that would be
unsafe/impossible for the kernel to hand directly to userspace, and
cannot be reproduced using data that can be handed to userspace.
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
KVM_CAP_NR_VCPUS is used to get the "recommended" maximum number of
VCPUs and arm64/mips/riscv report num_online_cpus(). Powerpc reports
either num_online_cpus() or num_present_cpus(), s390 has multiple
constants depending on hardware features. On x86, KVM reports an
arbitrary value of '710' which is supposed to be the maximum tested
value but it's possible to test all KVM_MAX_VCPUS even when there are
less physical CPUs available.
Drop the arbitrary '710' value and return num_online_cpus() on x86 as
well. The recommendation will match other architectures and will mean
'no CPU overcommit'.
For reference, QEMU only queries KVM_CAP_NR_VCPUS to print a warning
when the requested vCPU number exceeds it. The static limit of '710'
is quite weird as smaller systems with just a few physical CPUs should
certainly "recommend" less.
Suggested-by: Eduardo Habkost <ehabkost@redhat.com>
Signed-off-by: Vitaly Kuznetsov <vkuznets@redhat.com>
Message-Id: <20211111134733.86601-1-vkuznets@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Currently when kvm_update_cpuid_runtime() runs, it assumes that the
KVM_CPUID_FEATURES leaf is located at 0x40000001. This is not true,
however, if Hyper-V support is enabled. In this case the KVM leaves will
be offset.
This patch introdues as new 'kvm_cpuid_base' field into struct
kvm_vcpu_arch to track the location of the KVM leaves and function
kvm_update_kvm_cpuid_base() (called from kvm_set_cpuid()) to locate the
leaves using the 'KVMKVMKVM\0\0\0' signature (which is now given a
definition in kvm_para.h). Adjustment of KVM_CPUID_FEATURES will hence now
target the correct leaf.
NOTE: A new for_each_possible_hypervisor_cpuid_base() macro is intoduced
into processor.h to avoid having duplicate code for the iteration
over possible hypervisor base leaves.
Signed-off-by: Paul Durrant <pdurrant@amazon.com>
Message-Id: <20211105095101.5384-3-pdurrant@amazon.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
KVM_GUESTDBG_BLOCKIRQ relies on interrupts being injected using
standard kvm's inject_pending_event, and not via APICv/AVIC.
Since this is a debug feature, just inhibit APICv/AVIC while
KVM_GUESTDBG_BLOCKIRQ is in use on at least one vCPU.
Fixes: 61e5f69ef0 ("KVM: x86: implement KVM_GUESTDBG_BLOCKIRQ")
Reported-by: Vitaly Kuznetsov <vkuznets@redhat.com>
Signed-off-by: Maxim Levitsky <mlevitsk@redhat.com>
Reviewed-by: Sean Christopherson <seanjc@google.com>
Tested-by: Sean Christopherson <seanjc@google.com>
Message-Id: <20211108090245.166408-1-mlevitsk@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
In commit b043138246 ("x86/KVM: Make sure KVM_VCPU_FLUSH_TLB flag is
not missed") we switched to using a gfn_to_pfn_cache for accessing the
guest steal time structure in order to allow for an atomic xchg of the
preempted field. This has a couple of problems.
Firstly, kvm_map_gfn() doesn't work at all for IOMEM pages when the
atomic flag is set, which it is in kvm_steal_time_set_preempted(). So a
guest vCPU using an IOMEM page for its steal time would never have its
preempted field set.
Secondly, the gfn_to_pfn_cache is not invalidated in all cases where it
should have been. There are two stages to the GFN->PFN conversion;
first the GFN is converted to a userspace HVA, and then that HVA is
looked up in the process page tables to find the underlying host PFN.
Correct invalidation of the latter would require being hooked up to the
MMU notifiers, but that doesn't happen---so it just keeps mapping and
unmapping the *wrong* PFN after the userspace page tables change.
In the !IOMEM case at least the stale page *is* pinned all the time it's
cached, so it won't be freed and reused by anyone else while still
receiving the steal time updates. The map/unmap dance only takes care
of the KVM administrivia such as marking the page dirty.
Until the gfn_to_pfn cache handles the remapping automatically by
integrating with the MMU notifiers, we might as well not get a
kernel mapping of it, and use the perfectly serviceable userspace HVA
that we already have. We just need to implement the atomic xchg on
the userspace address with appropriate exception handling, which is
fairly trivial.
Cc: stable@vger.kernel.org
Fixes: b043138246 ("x86/KVM: Make sure KVM_VCPU_FLUSH_TLB flag is not missed")
Signed-off-by: David Woodhouse <dwmw@amazon.co.uk>
Message-Id: <3645b9b889dac6438394194bb5586a46b68d581f.camel@infradead.org>
[I didn't entirely agree with David's assessment of the
usefulness of the gfn_to_pfn cache, and integrated the outcome
of the discussion in the above commit message. - Paolo]
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Add guest api and guest kernel support for SEV live migration.
Introduces a new hypercall to notify the host of changes to the page
encryption status. If the page is encrypted then it must be migrated
through the SEV firmware or a helper VM sharing the key. If page is
not encrypted then it can be migrated normally by userspace. This new
hypercall is invoked using paravirt_ops.
Conflicts: sev_active() replaced by cc_platform_has(CC_ATTR_GUEST_MEM_ENCRYPT).
The guest support for detecting and enabling SEV Live migration
feature uses the following logic :
- kvm_init_plaform() checks if its booted under the EFI
- If not EFI,
i) if kvm_para_has_feature(KVM_FEATURE_MIGRATION_CONTROL), issue a wrmsrl()
to enable the SEV live migration support
- If EFI,
i) If kvm_para_has_feature(KVM_FEATURE_MIGRATION_CONTROL), read
the UEFI variable which indicates OVMF support for live migration
ii) the variable indicates live migration is supported, issue a wrmsrl() to
enable the SEV live migration support
The EFI live migration check is done using a late_initcall() callback.
Also, ensure that _bss_decrypted section is marked as decrypted in the
hypervisor's guest page encryption status tracking.
Signed-off-by: Ashish Kalra <ashish.kalra@amd.com>
Reviewed-by: Steve Rutherford <srutherford@google.com>
Message-Id: <b4453e4c87103ebef12217d2505ea99a1c3e0f0f.1629726117.git.ashish.kalra@amd.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
KVM hypercall framework relies on alternative framework to patch the
VMCALL -> VMMCALL on AMD platform. If a hypercall is made before
apply_alternative() is called then it defaults to VMCALL. The approach
works fine on non SEV guest. A VMCALL would causes #UD, and hypervisor
will be able to decode the instruction and do the right things. But
when SEV is active, guest memory is encrypted with guest key and
hypervisor will not be able to decode the instruction bytes.
To highlight the need to provide this interface, capturing the
flow of apply_alternatives() :
setup_arch() call init_hypervisor_platform() which detects
the hypervisor platform the kernel is running under and then the
hypervisor specific initialization code can make early hypercalls.
For example, KVM specific initialization in case of SEV will try
to mark the "__bss_decrypted" section's encryption state via early
page encryption status hypercalls.
Now, apply_alternatives() is called much later when setup_arch()
calls check_bugs(), so we do need some kind of an early,
pre-alternatives hypercall interface. Other cases of pre-alternatives
hypercalls include marking per-cpu GHCB pages as decrypted on SEV-ES
and per-cpu apf_reason, steal_time and kvm_apic_eoi as decrypted for
SEV generally.
Add SEV specific hypercall3, it unconditionally uses VMMCALL. The hypercall
will be used by the SEV guest to notify encrypted pages to the hypervisor.
This kvm_sev_hypercall3() function is abstracted and used as follows :
All these early hypercalls are made through early_set_memory_XX() interfaces,
which in turn invoke pv_ops (paravirt_ops).
This early_set_memory_XX() -> pv_ops.mmu.notify_page_enc_status_changed()
is a generic interface and can easily have SEV, TDX and any other
future platform specific abstractions added to it.
Currently, pv_ops.mmu.notify_page_enc_status_changed() callback is setup to
invoke kvm_sev_hypercall3() in case of SEV.
Similarly, in case of TDX, pv_ops.mmu.notify_page_enc_status_changed()
can be setup to a TDX specific callback.
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: "H. Peter Anvin" <hpa@zytor.com>
Cc: Paolo Bonzini <pbonzini@redhat.com>
Cc: Joerg Roedel <joro@8bytes.org>
Cc: Borislav Petkov <bp@suse.de>
Cc: Tom Lendacky <thomas.lendacky@amd.com>
Cc: x86@kernel.org
Cc: kvm@vger.kernel.org
Cc: linux-kernel@vger.kernel.org
Reviewed-by: Steve Rutherford <srutherford@google.com>
Reviewed-by: Venu Busireddy <venu.busireddy@oracle.com>
Signed-off-by: Brijesh Singh <brijesh.singh@amd.com>
Signed-off-by: Ashish Kalra <ashish.kalra@amd.com>
Message-Id: <6fd25c749205dd0b1eb492c60d41b124760cc6ae.1629726117.git.ashish.kalra@amd.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Commit 66558b730f ("sched: Add cluster scheduler level for x86")
introduced cpu_l2c_shared_map mask which is expected to be initialized
by smp_op.smp_prepare_cpus(). That commit only updated
native_smp_prepare_cpus() version but not xen_pv_smp_prepare_cpus().
As result Xen PV guests crash in set_cpu_sibling_map().
While the new mask can be allocated in xen_pv_smp_prepare_cpus() one can
see that both versions of smp_prepare_cpus ops share a number of common
operations that can be factored out. So do that instead.
Fixes: 66558b730f ("sched: Add cluster scheduler level for x86")
Signed-off-by: Boris Ostrovsky <boris.ostrovsky@oracle.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Reviewed-by: Juergen Gross <jgross@suse.com>
Link: https://lkml.kernel.org/r/1635896196-18961-1-git-send-email-boris.ostrovsky@oracle.com
Add a few signature bytes after the static call trampoline and verify
those bytes match before patching the trampoline. This avoids patching
random other JMPs (such as CFI jump-table entries) instead.
These bytes decode as:
d: 53 push %rbx
e: 43 54 rex.XB push %r12
And happen to spell "SCT".
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Link: https://lkml.kernel.org/r/20211030074758.GT174703@worktop.programming.kicks-ass.net
Pull asm-generic cleanup from Arnd Bergmann:
"This is a single cleanup from Peter Collingbourne, removing some dead
code"
* tag 'asm-generic-5.16' of git://git.kernel.org/pub/scm/linux/kernel/git/arnd/asm-generic:
arch: remove unused function syscall_set_arguments()
Pull xen updates from Juergen Gross:
- a series to speed up the boot of Xen PV guests
- some cleanups in Xen related code
- replacement of license texts with the appropriate SPDX headers and
fixing of wrong SPDX headers in Xen header files
- a small series making paravirtualized interrupt masking much simpler
and at the same time removing complaints of objtool
- a fix for Xen ballooning hogging workqueues for too long
- enablement of the Xen pciback driver for Arm
- some further small fixes/enhancements
* tag 'for-linus-5.16b-rc1-tag' of git://git.kernel.org/pub/scm/linux/kernel/git/xen/tip: (22 commits)
xen/balloon: fix unused-variable warning
xen/balloon: rename alloc/free_xenballooned_pages
xen/balloon: add late_initcall_sync() for initial ballooning done
x86/xen: remove 32-bit awareness from startup_xen
xen: remove highmem remnants
xen: allow pv-only hypercalls only with CONFIG_XEN_PV
x86/xen: remove 32-bit pv leftovers
xen-pciback: allow compiling on other archs than x86
x86/xen: switch initial pvops IRQ functions to dummy ones
x86/xen: remove xen_have_vcpu_info_placement flag
x86/pvh: add prototype for xen_pvh_init()
xen: Fix implicit type conversion
xen: fix wrong SPDX headers of Xen related headers
xen/pvcalls-back: Remove redundant 'flush_workqueue()' calls
x86/xen: Remove redundant irq_enter/exit() invocations
xen-pciback: Fix return in pm_ctrl_init()
xen/x86: restrict PV Dom0 identity mapping
xen/x86: there's no highmem anymore in PV mode
xen/x86: adjust handling of the L3 user vsyscall special page table
xen/x86: adjust xen_set_fixmap()
...
Pull iommu updates from Joerg Roedel:
- Intel IOMMU Updates fro Lu Baolu:
- Dump DMAR translation structure when DMA fault occurs
- An optimization in the page table manipulation code
- Use second level for GPA->HPA translation
- Various cleanups
- Arm SMMU Updates from Will
- Minor optimisations to SMMUv3 command creation and submission
- Numerous new compatible string for Qualcomm SMMUv2 implementations
- Fixes for the SWIOTLB based implemenation of dma-iommu code for
untrusted devices
- Add support for r8a779a0 to the Renesas IOMMU driver and DT matching
code for r8a77980
- A couple of cleanups and fixes for the Apple DART IOMMU driver
- Make use of generic report_iommu_fault() interface in the AMD IOMMU
driver
- Various smaller fixes and cleanups
* tag 'iommu-updates-v5.16' of git://git.kernel.org/pub/scm/linux/kernel/git/joro/iommu: (35 commits)
iommu/dma: Fix incorrect error return on iommu deferred attach
iommu/dart: Initialize DART_STREAMS_ENABLE
iommu/dma: Use kvcalloc() instead of kvzalloc()
iommu/tegra-smmu: Use devm_bitmap_zalloc when applicable
iommu/dart: Use kmemdup instead of kzalloc and memcpy
iommu/vt-d: Avoid duplicate removing in __domain_mapping()
iommu/vt-d: Convert the return type of first_pte_in_page to bool
iommu/vt-d: Clean up unused PASID updating functions
iommu/vt-d: Delete dev_has_feat callback
iommu/vt-d: Use second level for GPA->HPA translation
iommu/vt-d: Check FL and SL capability sanity in scalable mode
iommu/vt-d: Remove duplicate identity domain flag
iommu/vt-d: Dump DMAR translation structure when DMA fault occurs
iommu/vt-d: Do not falsely log intel_iommu is unsupported kernel option
iommu/arm-smmu-qcom: Request direct mapping for modem device
iommu: arm-smmu-qcom: Add compatible for QCM2290
dt-bindings: arm-smmu: Add compatible for QCM2290 SoC
iommu/arm-smmu-qcom: Add SM6350 SMMU compatible
dt-bindings: arm-smmu: Add compatible for SM6350 SoC
iommu/arm-smmu-v3: Properly handle the return value of arm_smmu_cmdq_build_cmd()
...
