The 'pmu' pointer cannot be NULL, as it is taken as a pointer to an array.
Remove the superfluous NULL check.

Found by Coverity: CID#1497507.

Signed-off-by: Jiri Slaby (SUSE) <jirislaby@kernel.org>
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Cc: Liang Kan <kan.liang@linux.intel.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Link: https://patch.msgid.link/20251119091538.825307-1-jirislaby@kernel.org

Don't update the LBR MSR intercept bitmaps if they're already up-to-date,
as unconditionally updating the intercepts forces KVM to recalculate the
MSR bitmaps for vmcb02 on every nested VMRUN.  The redundant updates are
functionally okay; however, they neuter an optimization in Hyper-V
nested virtualization enlightenments and this manifests as a self-test
failure.

In particular, Hyper-V lets L1 mark "nested enlightenments" as clean, i.e.
tell KVM that no changes were made to the MSR bitmap since the last VMRUN.
The hyperv_svm_test KVM selftest intentionally changes the MSR bitmap
"without telling KVM about it" to verify that KVM honors the clean hint,
correctly fails because KVM notices the changed bitmap anyway:

  ==== Test Assertion Failure ====
  x86/hyperv_svm_test.c:120: vmcb->control.exit_code == 0x081
  pid=193558 tid=193558 errno=4 - Interrupted system call
     1	0x0000000000411361: assert_on_unhandled_exception at processor.c:659
     2	0x0000000000406186: _vcpu_run at kvm_util.c:1699
     3	 (inlined by) vcpu_run at kvm_util.c:1710
     4	0x0000000000401f2a: main at hyperv_svm_test.c:175
     5	0x000000000041d0d3: __libc_start_call_main at libc-start.o:?
     6	0x000000000041f27c: __libc_start_main_impl at ??:?
     7	0x00000000004021a0: _start at ??:?
  vmcb->control.exit_code == SVM_EXIT_VMMCALL

Do *not* fix this by skipping svm_hv_vmcb_dirty_nested_enlightenments()
when svm_set_intercept_for_msr() performs a no-op change.  changes to
the L0 MSR interception bitmap are only triggered by full CPUID updates
and MSR filter updates, both of which should be rare.  Changing
svm_set_intercept_for_msr() risks hiding unintended pessimizations
like this one, and is actually more complex than this change.

Fixes: fbe5e5f030c2 ("KVM: nSVM: Always recalculate LBR MSR intercepts in svm_update_lbrv()")
Cc: stable@vger.kernel.org
Signed-off-by: Yosry Ahmed <yosry.ahmed@linux.dev>
Link: https://patch.msgid.link/20251112013017.1836863-1-yosry.ahmed@linux.dev
[Rewritten commit message based on mailing list discussion. - Paolo]
Reviewed-by: Sean Christopherson <seanjc@google.com>
Tested-by: Sean Christopherson <seanjc@google.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>

Pull x86 fixes from Ingo Molnar:

 - Update the list of AMD microcode minimum Entrysign revisions

 - Add additional fixed AMD RDSEED microcode revisions

 - Update the language transliteration for Kiryl Shutsemau's name
   in the MAINTAINERS entry

* tag 'x86-urgent-2025-11-15' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  x86/microcode/AMD: Add Zen5 model 0x44, stepping 0x1 minrev
  x86/CPU/AMD: Add additional fixed RDSEED microcode revisions
  MAINTAINERS: Update name spelling

Pull bpf fixes from Alexei Starovoitov:

 - Fix interaction between livepatch and BPF fexit programs (Song Liu)
   With Steven and Masami acks.

 - Fix stack ORC unwind from BPF kprobe_multi (Jiri Olsa)
   With Steven and Masami acks.

 - Fix out of bounds access in widen_imprecise_scalars() in the verifier
   (Eduard Zingerman)

 - Fix conflicts between MPTCP and BPF sockmap (Jiayuan Chen)

 - Fix net_sched storage collision with BPF data_meta/data_end (Eric
   Dumazet)

 - Add _impl suffix to BPF kfuncs with implicit args to avoid breaking
   them in bpf-next when KF_IMPLICIT_ARGS is added (Mykyta Yatsenko)

* tag 'bpf-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/bpf/bpf:
  selftests/bpf: Test widen_imprecise_scalars() with different stack depth
  bpf: account for current allocated stack depth in widen_imprecise_scalars()
  bpf: Add bpf_prog_run_data_pointers()
  selftests/bpf: Add mptcp test with sockmap
  mptcp: Fix proto fallback detection with BPF
  mptcp: Disallow MPTCP subflows from sockmap
  selftests/bpf: Add stacktrace ips test for raw_tp
  selftests/bpf: Add stacktrace ips test for kprobe_multi/kretprobe_multi
  x86/fgraph,bpf: Fix stack ORC unwind from kprobe_multi return probe
  Revert "perf/x86: Always store regs->ip in perf_callchain_kernel()"
  bpf: add _impl suffix for bpf_stream_vprintk() kfunc
  bpf:add _impl suffix for bpf_task_work_schedule* kfuncs
  selftests/bpf: Add tests for livepatch + bpf trampoline
  ftrace: bpf: Fix IPMODIFY + DIRECT in modify_ftrace_direct()
  ftrace: Fix BPF fexit with livepatch

Add the minimum Entrysign revision for that model+stepping to the list
of minimum revisions.

Fixes: 50cef76d5cb0 ("x86/microcode/AMD: Load only SHA256-checksummed patches")
Reported-by: Andrew Cooper <andrew.cooper3@citrix.com>
Signed-off-by: Borislav Petkov (AMD) <bp@alien8.de>
Cc: <stable@kernel.org>
Link: https://lore.kernel.org/r/e94dd76b-4911-482f-8500-5c848a3df026@citrix.com

Microcode that resolves the RDSEED failure (SB-7055 [1]) has been released for
additional Zen5 models to linux-firmware [2]. Update the zen5_rdseed_microcode
array to cover these new models.

Fixes: 607b9fb2ce24 ("x86/CPU/AMD: Add RDSEED fix for Zen5")
Signed-off-by: Mario Limonciello <mario.limonciello@amd.com>
Signed-off-by: Borislav Petkov (AMD) <bp@alien8.de>
Cc: <stable@kernel.org>
Link: https://www.amd.com/en/resources/product-security/bulletin/amd-sb-7055.html [1]
Link: https://gitlab.com/kernel-firmware/linux-firmware/-/commit/6167e5566900cf236f7a69704e8f4c441bc7212a [2]
Link: https://patch.msgid.link/20251113223608.1495655-1-mario.limonciello@amd.com

Pull ACPI fixes from Rafael Wysocki:
 "These fix issues in the ACPI CPPC library and in the recently added
  parser for the ACPI MRRM table:

   - Limit some checks in the ACPI CPPC library to online CPUs to avoid
     accessing uninitialized per-CPU variables when some CPUs are
     offline to start with, like during boot with 'nosmt=force' (Gautham
     Shenoy)

   - Rework add_boot_memory_ranges() in the ACPI MRRM table parser to
     fix memory leaks and improve error handling (Kaushlendra Kumar)"

* tag 'acpi-6.18-rc6' of git://git.kernel.org/pub/scm/linux/kernel/git/rafael/linux-pm:
  ACPI: MRRM: Fix memory leaks and improve error handling
  ACPI: CPPC: Limit perf ctrs in PCC check only to online CPUs
  ACPI: CPPC: Perform fast check switch only for online CPUs
  ACPI: CPPC: Check _CPC validity for only the online CPUs
  ACPI: CPPC: Detect preferred core availability on online CPUs

Merge ACPI CPPC library fixes and an ACPI MRRM table parser fix for
6.18-rc6.

* acpi-cppc:
  ACPI: CPPC: Limit perf ctrs in PCC check only to online CPUs
  ACPI: CPPC: Perform fast check switch only for online CPUs
  ACPI: CPPC: Check _CPC validity for only the online CPUs
  ACPI: CPPC: Detect preferred core availability on online CPUs

* acpi-tables:
  ACPI: MRRM: Fix memory leaks and improve error handling

Pull kvm fixes from Paolo Bonzini:
 "Arm:

   - Fix trapping regression when no in-kernel irqchip is present

   - Check host-provided, untrusted ranges and offsets in pKVM

   - Fix regression restoring the ID_PFR1_EL1 register

   - Fix vgic ITS locking issues when LPIs are not directly injected

  Arm selftests:

   - Correct target CPU programming in vgic_lpi_stress selftest

   - Fix exposure of SCTLR2_EL2 and ZCR_EL2 in get-reg-list selftest

  RISC-V:

   - Fix check for local interrupts on riscv32

   - Read HGEIP CSR on the correct cpu when checking for IMSIC
     interrupts

   - Remove automatic I/O mapping from kvm_arch_prepare_memory_region()

  x86:

   - Inject #UD if the guest attempts to execute SEAMCALL or TDCALL as
     KVM doesn't support virtualization the instructions, but the
     instructions are gated only by VMXON. That is, they will VM-Exit
     instead of taking a #UD and until now this resulted in KVM exiting
     to userspace with an emulation error.

   - Unload the "FPU" when emulating INIT of XSTATE features if and only
     if the FPU is actually loaded, instead of trying to predict when
     KVM will emulate an INIT (CET support missed the MP_STATE path).
     Add sanity checks to detect and harden against similar bugs in the
     future.

   - Unregister KVM's GALog notifier (for AVIC) when kvm-amd.ko is
     unloaded.

   - Use a raw spinlock for svm->ir_list_lock as the lock is taken
     during schedule(), and "normal" spinlocks are sleepable locks when
     PREEMPT_RT=y.

   - Remove guest_memfd bindings on memslot deletion when a gmem file is
     dying to fix a use-after-free race found by syzkaller.

   - Fix a goof in the EPT Violation handler where KVM checks the wrong
     variable when determining if the reported GVA is valid.

   - Fix and simplify the handling of LBR virtualization on AMD, which
     was made buggy and unnecessarily complicated by nested VM support

  Misc:

   - Update Oliver's email address"

* tag 'for-linus' of git://git.kernel.org/pub/scm/virt/kvm/kvm: (28 commits)
  KVM: nSVM: Fix and simplify LBR virtualization handling with nested
  KVM: nSVM: Always recalculate LBR MSR intercepts in svm_update_lbrv()
  KVM: SVM: Mark VMCB_LBR dirty when MSR_IA32_DEBUGCTLMSR is updated
  MAINTAINERS: Switch myself to using kernel.org address
  KVM: arm64: vgic-v3: Release reserved slot outside of lpi_xa's lock
  KVM: arm64: vgic-v3: Reinstate IRQ lock ordering for LPI xarray
  KVM: arm64: Limit clearing of ID_{AA64PFR0,PFR1}_EL1.GIC to userspace irqchip
  KVM: arm64: Set ID_{AA64PFR0,PFR1}_EL1.GIC when GICv3 is configured
  KVM: arm64: Make all 32bit ID registers fully writable
  KVM: VMX: Fix check for valid GVA on an EPT violation
  KVM: guest_memfd: Remove bindings on memslot deletion when gmem is dying
  KVM: SVM: switch to raw spinlock for svm->ir_list_lock
  KVM: SVM: Make avic_ga_log_notifier() local to avic.c
  KVM: SVM: Unregister KVM's GALog notifier on kvm-amd.ko exit
  KVM: SVM: Initialize per-CPU svm_data at the end of hardware setup
  KVM: x86: Call out MSR_IA32_S_CET is not handled by XSAVES
  KVM: x86: Harden KVM against imbalanced load/put of guest FPU state
  KVM: x86: Unload "FPU" state on INIT if and only if its currently in-use
  KVM: arm64: Check the untrusted offset in FF-A memory share
  KVM: arm64: Check range args for pKVM mem transitions
  ...

The current scheme for handling LBRV when nested is used is very
complicated, especially when L1 does not enable LBRV (i.e. does not set
LBR_CTL_ENABLE_MASK).

To avoid copying LBRs between VMCB01 and VMCB02 on every nested
transition, the current implementation switches between using VMCB01 or
VMCB02 as the source of truth for the LBRs while L2 is running. If L2
enables LBR, VMCB02 is used as the source of truth. When L2 disables
LBR, the LBRs are copied to VMCB01 and VMCB01 is used as the source of
truth. This introduces significant complexity, and incorrect behavior in
some cases.

For example, on a nested #VMEXIT, the LBRs are only copied from VMCB02
to VMCB01 if LBRV is enabled in VMCB01. This is because L2's writes to
MSR_IA32_DEBUGCTLMSR to enable LBR are intercepted and propagated to
VMCB01 instead of VMCB02. However, LBRV is only enabled in VMCB02 when
L2 is running.

This means that if L2 enables LBR and exits to L1, the LBRs will not be
propagated from VMCB02 to VMCB01, because LBRV is disabled in VMCB01.

There is no meaningful difference in CPUID rate in L2 when copying LBRs
on every nested transition vs. the current approach, so do the simple
and correct thing and always copy LBRs between VMCB01 and VMCB02 on
nested transitions (when LBRV is disabled by L1). Drop the conditional
LBRs copying in __svm_{enable/disable}_lbrv() as it is now unnecessary.

VMCB02 becomes the only source of truth for LBRs when L2 is running,
regardless of LBRV being enabled by L1, drop svm_get_lbr_vmcb() and use
svm->vmcb directly in its place.

Fixes: 1d5a1b5860ed ("KVM: x86: nSVM: correctly virtualize LBR msrs when L2 is running")
Cc: stable@vger.kernel.org
Signed-off-by: Yosry Ahmed <yosry.ahmed@linux.dev>
Link: https://patch.msgid.link/20251108004524.1600006-4-yosry.ahmed@linux.dev
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>