Pull kvm fixes from Paolo Bonzini:
 "ARM:

   - Correctly expose GICv3 support even if no irqchip is created so
     that userspace doesn't observe it changing pointlessly (fixing a
     regression with QEMU)

   - Don't issue a hypercall to set the id-mapped vectors when protected
     mode is enabled (fix for pKVM in combination with CPUs affected by
     Spectre-v3a)

  x86 (five oneliners, of which the most interesting two are):

   - a NULL pointer dereference on INVPCID executed with paging
     disabled, but only if KVM is using shadow paging

   - an incorrect bsearch comparison function which could truncate the
     result and apply PMU event filtering incorrectly. This one comes
     with a selftests update too"

* tag 'for-linus' of git://git.kernel.org/pub/scm/virt/kvm/kvm:
  KVM: x86/mmu: fix NULL pointer dereference on guest INVPCID
  KVM: x86: hyper-v: fix type of valid_bank_mask
  KVM: Free new dirty bitmap if creating a new memslot fails
  KVM: eventfd: Fix false positive RCU usage warning
  selftests: kvm/x86: Verify the pmu event filter matches the correct event
  selftests: kvm/x86: Add the helper function create_pmu_event_filter
  kvm: x86/pmu: Fix the compare function used by the pmu event filter
  KVM: arm64: Don't hypercall before EL2 init
  KVM: arm64: vgic-v3: Consistently populate ID_AA64PFR0_EL1.GIC
  KVM: x86/mmu: Update number of zapped pages even if page list is stable

With shadow paging enabled, the INVPCID instruction results in a call
to kvm_mmu_invpcid_gva.  If INVPCID is executed with CR0.PG=0, the
invlpg callback is not set and the result is a NULL pointer dereference.
Fix it trivially by checking for mmu->invlpg before every call.

There are other possibilities:

- check for CR0.PG, because KVM (like all Intel processors after P5)
  flushes guest TLB on CR0.PG changes so that INVPCID/INVLPG are a
  nop with paging disabled

- check for EFER.LMA, because KVM syncs and flushes when switching
  MMU contexts outside of 64-bit mode

All of these are tricky, go for the simple solution.  This is CVE-2022-1789.

Reported-by: Yongkang Jia <kangel@zju.edu.cn>
Cc: stable@vger.kernel.org
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>

In kvm_hv_flush_tlb(), valid_bank_mask is declared as unsigned long,
but is used as u64, which is wrong for i386, and has been spotted by
LKP after applying "KVM: x86: hyper-v: replace bitmap_weight() with
hweight64()"

https://lore.kernel.org/lkml/20220510154750.212913-12-yury.norov@gmail.com/

But it's wrong even without that patch because now bitmap_weight()
dereferences a word after valid_bank_mask on i386.

>> include/asm-generic/bitops/const_hweight.h:21:76: warning: right shift count >= width of type
+[-Wshift-count-overflow]
      21 | #define __const_hweight64(w) (__const_hweight32(w) + __const_hweight32((w) >> 32))
         |                                                                            ^~
   include/asm-generic/bitops/const_hweight.h:10:16: note: in definition of macro '__const_hweight8'
      10 |          ((!!((w) & (1ULL << 0))) +     \
         |                ^
   include/asm-generic/bitops/const_hweight.h:20:31: note: in expansion of macro '__const_hweight16'
      20 | #define __const_hweight32(w) (__const_hweight16(w) + __const_hweight16((w) >> 16))
         |                               ^~~~~~~~~~~~~~~~~
   include/asm-generic/bitops/const_hweight.h:21:54: note: in expansion of macro '__const_hweight32'
      21 | #define __const_hweight64(w) (__const_hweight32(w) + __const_hweight32((w) >> 32))
         |                                                      ^~~~~~~~~~~~~~~~~
   include/asm-generic/bitops/const_hweight.h:29:49: note: in expansion of macro '__const_hweight64'
      29 | #define hweight64(w) (__builtin_constant_p(w) ? __const_hweight64(w) : __arch_hweight64(w))
         |                                                 ^~~~~~~~~~~~~~~~~
   arch/x86/kvm/hyperv.c:1983:36: note: in expansion of macro 'hweight64'
    1983 |                 if (hc->var_cnt != hweight64(valid_bank_mask))
         |                                    ^~~~~~~~~

CC: Borislav Petkov <bp@alien8.de>
CC: Dave Hansen <dave.hansen@linux.intel.com>
CC: H. Peter Anvin <hpa@zytor.com>
CC: Ingo Molnar <mingo@redhat.com>
CC: Jim Mattson <jmattson@google.com>
CC: Joerg Roedel <joro@8bytes.org>
CC: Paolo Bonzini <pbonzini@redhat.com>
CC: Sean Christopherson <seanjc@google.com>
CC: Thomas Gleixner <tglx@linutronix.de>
CC: Vitaly Kuznetsov <vkuznets@redhat.com>
CC: Wanpeng Li <wanpengli@tencent.com>
CC: kvm@vger.kernel.org
CC: linux-kernel@vger.kernel.org
CC: x86@kernel.org
Reported-by: kernel test robot <lkp@intel.com>
Signed-off-by: Yury Norov <yury.norov@gmail.com>
Message-Id: <20220519171504.1238724-1-yury.norov@gmail.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>

When returning from the compare function the u64 is truncated to an
int.  This results in a loss of the high nybble[1] in the event select
and its sign if that nybble is in use.  Switch from using a result that
can end up being truncated to a result that can only be: 1, 0, -1.

[1] bits 35:32 in the event select register and bits 11:8 in the event
    select.

Fixes: 7ff775aca48ad ("KVM: x86/pmu: Use binary search to check filtered events")
Signed-off-by: Aaron Lewis <aaronlewis@google.com>
Reviewed-by: Sean Christopherson <seanjc@google.com>
Message-Id: <20220517051238.2566934-1-aaronlewis@google.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>

The unused part precedes the new range spanned by the start, end parameters
of vmemmap_use_new_sub_pmd(). This means it actually goes from
ALIGN_DOWN(start, PMD_SIZE) up to start.

Use the correct address when applying the mark using memset.

Fixes: 8d400913c231 ("x86/vmemmap: handle unpopulated sub-pmd ranges")
Signed-off-by: Adrian-Ken Rueegsegger <ken@codelabs.ch>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Oscar Salvador <osalvador@suse.de>
Reviewed-by: David Hildenbrand <david@redhat.com>
Cc: stable@vger.kernel.org
Link: https://lore.kernel.org/r/20220509090637.24152-2-ken@codelabs.ch

When zapping obsolete pages, update the running count of zapped pages
regardless of whether or not the list has become unstable due to zapping
a shadow page with its own child shadow pages.  If the VM is backed by
mostly 4kb pages, KVM can zap an absurd number of SPTEs without bumping
the batch count and thus without yielding.  In the worst case scenario,
this can cause a soft lokcup.

 watchdog: BUG: soft lockup - CPU#12 stuck for 22s! [dirty_log_perf_:13020]
   RIP: 0010:workingset_activation+0x19/0x130
   mark_page_accessed+0x266/0x2e0
   kvm_set_pfn_accessed+0x31/0x40
   mmu_spte_clear_track_bits+0x136/0x1c0
   drop_spte+0x1a/0xc0
   mmu_page_zap_pte+0xef/0x120
   __kvm_mmu_prepare_zap_page+0x205/0x5e0
   kvm_mmu_zap_all_fast+0xd7/0x190
   kvm_mmu_invalidate_zap_pages_in_memslot+0xe/0x10
   kvm_page_track_flush_slot+0x5c/0x80
   kvm_arch_flush_shadow_memslot+0xe/0x10
   kvm_set_memslot+0x1a8/0x5d0
   __kvm_set_memory_region+0x337/0x590
   kvm_vm_ioctl+0xb08/0x1040

Fixes: fbb158cb88b6 ("KVM: x86/mmu: Revert "Revert "KVM: MMU: zap pages in batch""")
Reported-by: David Matlack <dmatlack@google.com>
Reviewed-by: Ben Gardon <bgardon@google.com>
Cc: stable@vger.kernel.org
Signed-off-by: Sean Christopherson <seanjc@google.com>
Message-Id: <20220511145122.3133334-1-seanjc@google.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>

Pull x86 fix from Thomas Gleixner:
 "A fix and an email address update:

   - Prevent FPU state corruption.

     The condition in irq_fpu_usable() grants FPU usage when the FPU is
     not used in the kernel. That's just wrong as it does not take the
     fpregs_lock()'ed regions into account. If FPU usage happens within
     such a region from interrupt context, then the FPU state gets
     corrupted.

     That's a long standing bug, which got unearthed by the recent
     changes to the random code.

   - Josh wants to use his kernel.org email address"

* tag 'x86-urgent-2022-05-08' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  x86/fpu: Prevent FPU state corruption
  MAINTAINERS: Update Josh Poimboeuf's email address

Pull kvm fixes from Paolo Bonzini:
 "x86:

   - Account for family 17h event renumberings in AMD PMU emulation

   - Remove CPUID leaf 0xA on AMD processors

   - Fix lockdep issue with locking all vCPUs

   - Fix loss of A/D bits in SPTEs

   - Fix syzkaller issue with invalid guest state"

* tag 'for-linus' of git://git.kernel.org/pub/scm/virt/kvm/kvm:
  KVM: VMX: Exit to userspace if vCPU has injected exception and invalid state
  KVM: SEV: Mark nested locking of vcpu->lock
  kvm: x86/cpuid: Only provide CPUID leaf 0xA if host has architectural PMU
  KVM: x86/svm: Account for family 17h event renumberings in amd_pmc_perf_hw_id
  KVM: x86/mmu: Use atomic XCHG to write TDP MMU SPTEs with volatile bits
  KVM: x86/mmu: Move shadow-present check out of spte_has_volatile_bits()
  KVM: x86/mmu: Don't treat fully writable SPTEs as volatile (modulo A/D)

Exit to userspace with an emulation error if KVM encounters an injected
exception with invalid guest state, in addition to the existing check of
bailing if there's a pending exception (KVM doesn't support emulating
exceptions except when emulating real mode via vm86).

In theory, KVM should never get to such a situation as KVM is supposed to
exit to userspace before injecting an exception with invalid guest state.
But in practice, userspace can intervene and manually inject an exception
and/or stuff registers to force invalid guest state while a previously
injected exception is awaiting reinjection.

Fixes: fc4fad79fc3d ("KVM: VMX: Reject KVM_RUN if emulation is required with pending exception")
Reported-by: syzbot+cfafed3bb76d3e37581b@syzkaller.appspotmail.com
Signed-off-by: Sean Christopherson <seanjc@google.com>
Message-Id: <20220502221850.131873-1-seanjc@google.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>

svm_vm_migrate_from() uses sev_lock_vcpus_for_migration() to lock all
source and target vcpu->locks. Unfortunately there is an 8 subclass
limit, so a new subclass cannot be used for each vCPU. Instead maintain
ownership of the first vcpu's mutex.dep_map using a role specific
subclass: source vs target. Release the other vcpu's mutex.dep_maps.

Fixes: b56639318bb2b ("KVM: SEV: Add support for SEV intra host migration")
Reported-by: John Sperbeck<jsperbeck@google.com>
Suggested-by: David Rientjes <rientjes@google.com>
Suggested-by: Sean Christopherson <seanjc@google.com>
Suggested-by: Paolo Bonzini <pbonzini@redhat.com>
Cc: Hillf Danton <hdanton@sina.com>
Cc: kvm@vger.kernel.org
Cc: linux-kernel@vger.kernel.org
Signed-off-by: Peter Gonda <pgonda@google.com>

Message-Id: <20220502165807.529624-1-pgonda@google.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>