linux-stable.git/tools/arch/x86/include, branch linux-6.3.y

Merge tag 'perf-tools-fixes-for-v6.3-1-2023-03-09' of git://git.kernel.org/pub/scm/linux/kernel/git/acme/linux

2023-03-10T16:18:46+00:00

Pull perf tools fixes from Arnaldo Carvalho de Melo:

 - Add Adrian Hunter to MAINTAINERS as a perf tools reviewer

 - Sync various tools/ copies of kernel headers with the kernel sources,
   this time trying to avoid first merging with upstream to then update
   but instead copy from upstream so that a merge is avoided and the end
   result after merging this pull request is the one expected,
   tools/perf/check-headers.sh (mostly) happy, less warnings while
   building tools/perf/

 - Fix counting when initial delay configured by setting
   perf_attr.enable_on_exec when starting workloads from the perf
   command line

 - Don't avoid emitting a PERF_RECORD_MMAP2 in 'perf inject
   --buildid-all' when that record comes with a build-id, otherwise we
   end up not being able to resolve symbols

 - Don't use comma as the CSV output separator the "stat+csv_output"
   test, as comma can appear on some tests as a modifier for an event,
   use @ instead, ditto for the JSON linter test

 - The offcpu test was looking for some bits being set on
   task_struct->prev_state without masking other bits not important for
   this specific 'perf test', fix it

* tag 'perf-tools-fixes-for-v6.3-1-2023-03-09' of git://git.kernel.org/pub/scm/linux/kernel/git/acme/linux:
  perf tools: Add Adrian Hunter to MAINTAINERS as a reviewer
  tools headers UAPI: Sync linux/perf_event.h with the kernel sources
  tools headers x86 cpufeatures: Sync with the kernel sources
  tools include UAPI: Sync linux/vhost.h with the kernel sources
  tools arch x86: Sync the msr-index.h copy with the kernel sources
  tools headers kvm: Sync uapi/{asm/linux} kvm.h headers with the kernel sources
  tools include UAPI: Synchronize linux/fcntl.h with the kernel sources
  tools headers: Synchronize {linux,vdso}/bits.h with the kernel sources
  tools headers UAPI: Sync linux/prctl.h with the kernel sources
  tools headers: Update the copy of x86's mem{cpy,set}_64.S used in 'perf bench'
  perf stat: Fix counting when initial delay configured
  tools headers svm: Sync svm headers with the kernel sources
  perf test: Avoid counting commas in json linter
  perf tests stat+csv_output: Switch CSV separator to @
  perf inject: Fix --buildid-all not to eat up MMAP2
  tools arch x86: Sync the msr-index.h copy with the kernel sources
  perf test: Fix offcpu test prev_state check

tools headers x86 cpufeatures: Sync with the kernel sources

2023-03-06T17:42:12+00:00

To pick the changes from:

  8415a74852d7c247 ("x86/cpu, kvm: Add support for CPUID_80000021_EAX")

This only causes these perf files to be rebuilt:

  CC       /tmp/build/perf/bench/mem-memcpy-x86-64-asm.o
  CC       /tmp/build/perf/bench/mem-memset-x86-64-asm.o

And addresses these perf build warnings:

  Warning: Kernel ABI header at 'tools/arch/x86/include/asm/disabled-features.h' differs from latest version at 'arch/x86/include/asm/disabled-features.h'
  diff -u tools/arch/x86/include/asm/disabled-features.h arch/x86/include/asm/disabled-features.h
  Warning: Kernel ABI header at 'tools/arch/x86/include/asm/required-features.h' differs from latest version at 'arch/x86/include/asm/required-features.h'
  diff -u tools/arch/x86/include/asm/required-features.h arch/x86/include/asm/required-features.h

Cc: Adrian Hunter 
Cc: Borislav Petkov (AMD) 
Cc: Ian Rogers 
Cc: Jiri Olsa 
Cc: Kim Phillips 
Cc: Namhyung Kim 
Link: https://lore.kernel.org/lkml/ZAYlS2XTJ5hRtss7@kernel.org
Signed-off-by: Arnaldo Carvalho de Melo

tools arch x86: Sync the msr-index.h copy with the kernel sources

2023-03-04T02:24:11+00:00

To pick up the changes in:

  e7862eda309ecfcc ("x86/cpu: Support AMD Automatic IBRS")
  0125acda7d76b943 ("x86/bugs: Reset speculation control settings on init")
  38aaf921e92dc5cf ("perf/x86: Add Meteor Lake support")
  5b6fac3fa44bafee ("x86/resctrl: Detect and configure Slow Memory Bandwidth Allocation")
  dc2a3e857981f859 ("x86/resctrl: Add interface to read mbm_total_bytes_config")

Addressing these tools/perf build warnings:

    diff -u tools/arch/x86/include/asm/msr-index.h arch/x86/include/asm/msr-index.h
    Warning: Kernel ABI header at 'tools/arch/x86/include/asm/msr-index.h' differs from latest version at 'arch/x86/include/asm/msr-index.h'

That makes the beautification scripts to pick some new entries:

  $ tools/perf/trace/beauty/tracepoints/x86_msr.sh > before
  $ cp arch/x86/include/asm/msr-index.h tools/arch/x86/include/asm/msr-index.h
  $ tools/perf/trace/beauty/tracepoints/x86_msr.sh > after
  $ diff -u before after
  --- before    2023-03-03 18:26:51.766923522 -0300
  +++ after     2023-03-03 18:27:09.987415481 -0300
  @@ -267,9 +267,11 @@
        [0xc000010e - x86_64_specific_MSRs_offset] = "AMD64_LBR_SELECT",
        [0xc000010f - x86_64_specific_MSRs_offset] = "AMD_DBG_EXTN_CFG",
        [0xc0000200 - x86_64_specific_MSRs_offset] = "IA32_MBA_BW_BASE",
  +     [0xc0000280 - x86_64_specific_MSRs_offset] = "IA32_SMBA_BW_BASE",
        [0xc0000300 - x86_64_specific_MSRs_offset] = "AMD64_PERF_CNTR_GLOBAL_STATUS",
        [0xc0000301 - x86_64_specific_MSRs_offset] = "AMD64_PERF_CNTR_GLOBAL_CTL",
        [0xc0000302 - x86_64_specific_MSRs_offset] = "AMD64_PERF_CNTR_GLOBAL_STATUS_CLR",
  +     [0xc0000400 - x86_64_specific_MSRs_offset] = "IA32_EVT_CFG_BASE",
   };

   #define x86_AMD_V_KVM_MSRs_offset 0xc0010000
  $

Now one can trace systemwide asking to see backtraces to where that MSR
is being read/written, see this example with a previous update:

  # perf trace -e msr:*_msr/max-stack=32/ --filter="msr>=IA32_U_CET && msr<=IA32_INT_SSP_TAB"
  ^C#

If we use -v (verbose mode) we can see what it does behind the scenes:

  # perf trace -v -e msr:*_msr/max-stack=32/ --filter="msr>=IA32_U_CET && msr<=IA32_INT_SSP_TAB"
  Using CPUID AuthenticAMD-25-21-0
  0x6a0
  0x6a8
  New filter for msr:read_msr: (msr>=0x6a0 && msr<=0x6a8) && (common_pid != 597499 && common_pid != 3313)
  0x6a0
  0x6a8
  New filter for msr:write_msr: (msr>=0x6a0 && msr<=0x6a8) && (common_pid != 597499 && common_pid != 3313)
  mmap size 528384B
  ^C#

Example with a frequent msr:

  # perf trace -v -e msr:*_msr/max-stack=32/ --filter="msr==IA32_SPEC_CTRL" --max-events 2
  Using CPUID AuthenticAMD-25-21-0
  0x48
  New filter for msr:read_msr: (msr==0x48) && (common_pid != 2612129 && common_pid != 3841)
  0x48
  New filter for msr:write_msr: (msr==0x48) && (common_pid != 2612129 && common_pid != 3841)
  mmap size 528384B
  Looking at the vmlinux_path (8 entries long)
  symsrc__init: build id mismatch for vmlinux.
  Using /proc/kcore for kernel data
  Using /proc/kallsyms for symbols
     0.000 Timer/2525383 msr:write_msr(msr: IA32_SPEC_CTRL, val: 6)
                                       do_trace_write_msr ([kernel.kallsyms])
                                       do_trace_write_msr ([kernel.kallsyms])
                                       __switch_to_xtra ([kernel.kallsyms])
                                       __switch_to ([kernel.kallsyms])
                                       __schedule ([kernel.kallsyms])
                                       schedule ([kernel.kallsyms])
                                       futex_wait_queue_me ([kernel.kallsyms])
                                       futex_wait ([kernel.kallsyms])
                                       do_futex ([kernel.kallsyms])
                                       __x64_sys_futex ([kernel.kallsyms])
                                       do_syscall_64 ([kernel.kallsyms])
                                       entry_SYSCALL_64_after_hwframe ([kernel.kallsyms])
                                       __futex_abstimed_wait_common64 (/usr/lib64/libpthread-2.33.so)
     0.030 :0/0 msr:write_msr(msr: IA32_SPEC_CTRL, val: 2)
                                       do_trace_write_msr ([kernel.kallsyms])
                                       do_trace_write_msr ([kernel.kallsyms])
                                       __switch_to_xtra ([kernel.kallsyms])
                                       __switch_to ([kernel.kallsyms])
                                       __schedule ([kernel.kallsyms])
                                       schedule_idle ([kernel.kallsyms])
                                       do_idle ([kernel.kallsyms])
                                       cpu_startup_entry ([kernel.kallsyms])
                                       secondary_startup_64_no_verify ([kernel.kallsyms])
    #

Cc: Adrian Hunter 
Cc: Babu Moger 
Cc: Borislav Petkov (AMD) 
Cc: Breno Leitao 
Cc: Ian Rogers 
Cc: Ingo Molnar 
Cc: Jiri Olsa 
Cc: Kan Liang 
Cc: Kim Phillips 
Cc: Namhyung Kim 
Cc: Nikunj A Dadhania 
Link: https://lore.kernel.org/lkml/ZAJoaZ41+rU5H0vL@kernel.org
[ I had published the perf-tools branch before with the sync with ]
[ 8c29f01654053258 ("x86/sev: Add SEV-SNP guest feature negotiation support") ]
[ I removed it from this new sync ]
Signed-off-by: Arnaldo Carvalho de Melo

tools headers kvm: Sync uapi/{asm/linux} kvm.h headers with the kernel sources

2023-03-04T02:24:10+00:00

To pick up the changes in:

  89b0e7de3451a17f ("KVM: arm64: nv: Introduce nested virtualization VCPU feature")
  14329b825ffb7f27 ("KVM: x86/pmu: Introduce masked events to the pmu event filter")
  6213b701a9df0472 ("KVM: x86: Replace 0-length arrays with flexible arrays")
  3fd49805d19d1c56 ("KVM: s390: Extend MEM_OP ioctl by storage key checked cmpxchg")
  14329b825ffb7f27 ("KVM: x86/pmu: Introduce masked events to the pmu event filter")

That don't change functionality in tools/perf, as no new ioctl is added
for the 'perf trace' scripts to harvest.

This addresses these perf build warnings:

  Warning: Kernel ABI header at 'tools/include/uapi/linux/kvm.h' differs from latest version at 'include/uapi/linux/kvm.h'
  diff -u tools/include/uapi/linux/kvm.h include/uapi/linux/kvm.h
  Warning: Kernel ABI header at 'tools/arch/x86/include/uapi/asm/kvm.h' differs from latest version at 'arch/x86/include/uapi/asm/kvm.h'
  diff -u tools/arch/x86/include/uapi/asm/kvm.h arch/x86/include/uapi/asm/kvm.h
  Warning: Kernel ABI header at 'tools/arch/arm64/include/uapi/asm/kvm.h' differs from latest version at 'arch/arm64/include/uapi/asm/kvm.h'
  diff -u tools/arch/arm64/include/uapi/asm/kvm.h arch/arm64/include/uapi/asm/kvm.h

Cc: Aaron Lewis 
Cc: Adrian Hunter 
Cc: Christoffer Dall 
Cc: Ian Rogers 
Cc: Janis Schoetterl-Glausch 
Cc: Janosch Frank 
Cc: Jiri Olsa 
Cc: Kees Kook 
Cc: Namhyung Kim 
Cc: Oliver Upton 
Cc: Sean Christopherson 
Link: https://lore.kernel.org/lkml/ZAJlg7%2FfWDVGX0F3@kernel.org
Signed-off-by: Arnaldo Carvalho de Melo

tools headers svm: Sync svm headers with the kernel sources

2023-03-02T20:38:32+00:00

To pick the changes in:

  8c29f01654053258 ("x86/sev: Add SEV-SNP guest feature negotiation support")

That triggers:

  CC      /tmp/build/perf-tools/arch/x86/util/kvm-stat.o
  CC      /tmp/build/perf-tools/util/header.o
  LD      /tmp/build/perf-tools/arch/x86/util/perf-in.o
  LD      /tmp/build/perf-tools/arch/x86/perf-in.o
  LD      /tmp/build/perf-tools/arch/perf-in.o
  LD      /tmp/build/perf-tools/util/perf-in.o
  LD      /tmp/build/perf-tools/perf-in.o
  LINK    /tmp/build/perf-tools/perf

But this time causes no changes in tooling results, as the introduced
SVM_VMGEXIT_TERM_REQUEST exit reason wasn't added to SVM_EXIT_REASONS,
that is used in kvm-stat.c.

And addresses this perf build warning:

  Warning: Kernel ABI header at 'tools/arch/x86/include/uapi/asm/svm.h' differs from latest version at 'arch/x86/include/uapi/asm/svm.h'
  diff -u tools/arch/x86/include/uapi/asm/svm.h arch/x86/include/uapi/asm/svm.h

Cc: Adrian Hunter 
Cc: Borislav Petkov (AMD) 
Cc: Ian Rogers 
Cc: Jiri Olsa 
Cc: Namhyung Kim 
Cc: Nikunj A Dadhania 
Link: http://lore.kernel.org/lkml/
Signed-off-by: Arnaldo Carvalho de Melo

Merge tag 'objtool-core-2023-03-02' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip

2023-03-02T17:45:34+00:00

Pull objtool updates from Ingo Molnar:

 - Shrink 'struct instruction', to improve objtool performance & memory
   footprint

 - Other maximum memory usage reductions - this makes the build both
   faster, and fixes kernel build OOM failures on allyesconfig and
   similar configs when they try to build the final (large) vmlinux.o

 - Fix ORC unwinding when a kprobe (INT3) is set on a stack-modifying
   single-byte instruction (PUSH/POP or LEAVE). This requires the
   extension of the ORC metadata structure with a 'signal' field

 - Misc fixes & cleanups

* tag 'objtool-core-2023-03-02' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (22 commits)
  objtool: Fix ORC 'signal' propagation
  objtool: Remove instruction::list
  x86: Fix FILL_RETURN_BUFFER
  objtool: Fix overlapping alternatives
  objtool: Union instruction::{call_dest,jump_table}
  objtool: Remove instruction::reloc
  objtool: Shrink instruction::{type,visited}
  objtool: Make instruction::alts a single-linked list
  objtool: Make instruction::stack_ops a single-linked list
  objtool: Change arch_decode_instruction() signature
  x86/entry: Fix unwinding from kprobe on PUSH/POP instruction
  x86/unwind/orc: Add 'signal' field to ORC metadata
  objtool: Optimize layout of struct special_alt
  objtool: Optimize layout of struct symbol
  objtool: Allocate multiple structures with calloc()
  objtool: Make struct check_options static
  objtool: Make struct entries[] static and const
  objtool: Fix HOSTCC flag usage
  objtool: Properly support make V=1
  objtool: Install libsubcmd in build
  ...

Merge tag 'perf-tools-for-v6.3-1-2023-02-22' of git://git.kernel.org/pub/scm/linux/kernel/git/acme/linux

2023-02-23T18:29:51+00:00

Pull perf tools updates from Arnaldo Carvalho de Melo:
"Miscellaneous:

- Add Ian Rogers to MAINTAINERS as a perf tools reviewer.

- Add support for retire latency feature (pipeline stall of a
instruction compared to the previous one, in cycles) present on
some Intel processors.

- Add 'perf c2c' report option to show false sharing with adjacent
cachelines, to be used in machines with cacheline prefetching,
where accesses to a cacheline brings the next one too.

- Skip 'perf test bpf' when the required kernel-debuginfo package
isn't installed.

- Avoid d3-flame-graph package dependency in 'perf script flamegraph',
making this feature more generally available.

- Add JSON metric events to present CPI stall cycles in Power10.

- Assorted improvements/refactorings on the JSON metrics parsing
code.

perf lock contention:

- Add -o/--lock-owner option:

$ sudo ./perf lock contention -abo -- ./perf bench sched pipe
# Running 'sched/pipe' benchmark:
# Executed 1000000 pipe operations between two processes

Total time: 4.766 [sec]

4.766540 usecs/op
209795 ops/sec
contended total wait max wait avg wait pid owner

403 565.32 us 26.81 us 1.40 us -1 Unknown
4 27.99 us 8.57 us 7.00 us 1583145 sched-pipe
1 8.25 us 8.25 us 8.25 us 1583144 sched-pipe
1 2.03 us 2.03 us 2.03 us 5068 chrome

The owner is unknown in most cases. Filtering only for the
mutex locks, it will more likely get the owners.

- -S/--callstack-filter is to limit display entries having the given
string in the callstack:

$ sudo ./perf lock contention -abv -S net sleep 1
...
contended total wait max wait avg wait type caller

5 70.20 us 16.13 us 14.04 us spinlock __dev_queue_xmit+0xb6d
0xffffffffa5dd1c60 _raw_spin_lock+0x30
0xffffffffa5b8f6ed __dev_queue_xmit+0xb6d
0xffffffffa5cd8267 ip6_finish_output2+0x2c7
0xffffffffa5cdac14 ip6_finish_output+0x1d4
0xffffffffa5cdb477 ip6_xmit+0x457
0xffffffffa5d1fd17 inet6_csk_xmit+0xd7
0xffffffffa5c5f4aa __tcp_transmit_skb+0x54a
0xffffffffa5c6467d tcp_keepalive_timer+0x2fd

Please note that to have the -b option (BPF) working above one has
to build with BUILD_BPF_SKEL=1.

- Add more 'perf test' entries to test these new features.

perf script:

- Add 'cgroup' field for 'perf script' output:

$ perf record --all-cgroups -- true
$ perf script -F comm,pid,cgroup
true 337112 /user.slice/user-657345.slice/user@657345.service/...
true 337112 /user.slice/user-657345.slice/user@657345.service/...
true 337112 /user.slice/user-657345.slice/user@657345.service/...
true 337112 /user.slice/user-657345.slice/user@657345.service/...

- Add support for showing branch speculation information in 'perf
script' and in the 'perf report' raw dump (-D).

perf record:

- Fix 'perf record' segfault with --overwrite and --max-size.

perf test/bench:

- Switch basic BPF filtering test to use syscall tracepoint to avoid
the variable number of probes inserted when using the previous
probe point (do_epoll_wait) that happens on different CPU
architectures.

- Fix DWARF unwind test by adding non-inline to expected function in
a backtrace.

- Use 'grep -c' where the longer form 'grep | wc -l' was being used.

- Add getpid and execve benchmarks to 'perf bench syscall'.

Intel PT:

- Add support for synthesizing "cycle" events from Intel PT traces as
we support "instruction" events when Intel PT CYC packets are
available. This enables much more accurate profiles than when using
the regular 'perf record -e cycles' (the default) when the workload
lasts for very short periods (<10ms).

- .plt symbol handling improvements, better handling IBT (in the past
MPX) done in the context of decoding Intel PT processor traces,
IFUNC symbols on x86_64, static executables, understanding .plt.got
symbols on x86_64.

- Add a 'perf test' to test symbol resolution, part of the .plt
improvements series, this tests things like symbol size in contexts
where only the symbol start is available (kallsyms), etc.

- Better handle auxtrace/Intel PT data when using pipe mode (perf
record sleep 1|perf report).

- Fix symbol lookup with kcore with multiple segments match stext,
getting the symbol resolution to just show DSOs as unknown.

ARM:

- Timestamp improvements for ARM64 systems with ETMv4 (Embedded Trace
Macrocell v4).

- Ensure ARM64 CoreSight timestamps don't go backwards.

- Document that ARM64 SPE (Statistical Profiling Extension) is used
with 'perf c2c/mem'.

- Add raw decoding for ARM64 SPEv1.2 previous branch address.

- Update neoverse-n2-v2 ARM vendor events (JSON tables): topdown L1,
TLB, cache, branch, PE utilization and instruction mix metrics.

- Update decoder code for OpenCSD version 1.4, on ARM64 systems.

- Fix command line auto-complete of CPU events on aarch64.

Build:

- Fix 'perf probe' and 'perf test' when libtraceevent isn't linked,
as several tests use tracepoints, those should be skipped.

- More fallout fixes for the removal of tools/lib/traceevent/.

- Fix build error when linking with libpfm"

* tag 'perf-tools-for-v6.3-1-2023-02-22' of git://git.kernel.org/pub/scm/linux/kernel/git/acme/linux: (114 commits)
perf tests stat_all_metrics: Change true workload to sleep workload for system wide check
perf vendor events power10: Add JSON metric events to present CPI stall cycles in powerpc
perf intel-pt: Synthesize cycle events
perf c2c: Add report option to show false sharing in adjacent cachelines
perf record: Fix segfault with --overwrite and --max-size
perf stat: Avoid merging/aggregating metric counts twice
perf tools: Fix perf tool build error in util/pfm.c
perf tools: Fix auto-complete on aarch64
perf lock contention: Support old rw_semaphore type
perf lock contention: Add -o/--lock-owner option
perf lock contention: Fix to save callstack for the default modified
perf test bpf: Skip test if kernel-debuginfo is not present
perf probe: Update the exit error codes in function try_to_find_probe_trace_event
perf script: Fix missing Retire Latency fields option documentation
perf event x86: Add retire_lat when synthesizing PERF_SAMPLE_WEIGHT_STRUCT
perf test x86: Support the retire_lat (Retire Latency) sample_type check
perf test bpf: Check for libtraceevent support
perf script: Support Retire Latency
perf report: Support Retire Latency
perf lock contention: Support filters for different aggregation
...

Merge branch 'linus' into objtool/core, to pick up Xen dependencies

2023-02-23T08:16:39+00:00

Pick up dependencies - freshly merged upstream via xen-next - before applying
dependent objtool changes.

Signed-off-by: Ingo Molnar

tools arch x86: Sync the msr-index.h copy with the kernel sources

2023-02-22T19:23:30+00:00

To pick up the changes from these csets:

  8c29f01654053258 ("x86/sev: Add SEV-SNP guest feature negotiation support")

That cause no changes to tooling:

  $ tools/perf/trace/beauty/tracepoints/x86_msr.sh > before
  $ cp arch/x86/include/asm/msr-index.h tools/arch/x86/include/asm/msr-index.h
  $ tools/perf/trace/beauty/tracepoints/x86_msr.sh > after
  $ diff -u before after
  $

Just silences this perf build warning:

  Warning: Kernel ABI header at 'tools/arch/x86/include/asm/msr-index.h' differs from latest version at 'arch/x86/include/asm/msr-index.h'
  diff -u tools/arch/x86/include/asm/msr-index.h arch/x86/include/asm/msr-index.h

Cc: Borislav Petkov (AMD) 
Cc: Nikunj A Dadhania 
Link: https://lore.kernel.org/lkml/Y%2FZrNvtcijPWagCp@kernel.org/
Signed-off-by: Arnaldo Carvalho de Melo

Merge tag 'x86_cpu_for_v6.3_rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip

2023-02-21T22:51:40+00:00

Pull x86 cpuid updates from Borislav Petkov:

 - Cache the AMD debug registers in per-CPU variables to avoid MSR
   writes where possible, when supporting a debug registers swap feature
   for SEV-ES guests

 - Add support for AMD's version of eIBRS called Automatic IBRS which is
   a set-and-forget control of indirect branch restriction speculation
   resources on privilege change

 - Add support for a new x86 instruction - LKGS - Load kernel GS which
   is part of the FRED infrastructure

 - Reset SPEC_CTRL upon init to accomodate use cases like kexec which
   rediscover

 - Other smaller fixes and cleanups

* tag 'x86_cpu_for_v6.3_rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  x86/amd: Cache debug register values in percpu variables
  KVM: x86: Propagate the AMD Automatic IBRS feature to the guest
  x86/cpu: Support AMD Automatic IBRS
  x86/cpu, kvm: Add the SMM_CTL MSR not present feature
  x86/cpu, kvm: Add the Null Selector Clears Base feature
  x86/cpu, kvm: Move X86_FEATURE_LFENCE_RDTSC to its native leaf
  x86/cpu, kvm: Add the NO_NESTED_DATA_BP feature
  KVM: x86: Move open-coded CPUID leaf 0x80000021 EAX bit propagation code
  x86/cpu, kvm: Add support for CPUID_80000021_EAX
  x86/gsseg: Add the new  header to 
  x86/gsseg: Use the LKGS instruction if available for load_gs_index()
  x86/gsseg: Move load_gs_index() to its own new header file
  x86/gsseg: Make asm_load_gs_index() take an u16
  x86/opcode: Add the LKGS instruction to x86-opcode-map
  x86/cpufeature: Add the CPU feature bit for LKGS
  x86/bugs: Reset speculation control settings on init
  x86/cpu: Remove redundant extern x86_read_arch_cap_msr()