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Arnaldo Carvalho de Melo 7f7f86a7bd tools arch x86: Sync the msr-index.h copy with the kernel sources
To pick up the changes in:

  2b12993220 ("x86/speculation: Add RSB VM Exit protections")
  4af184ee8b ("tools/power turbostat: dump secondary Turbo-Ratio-Limit")
  4ad3278df6 ("x86/speculation: Disable RRSBA behavior")
  d7caac991f ("x86/cpu/amd: Add Spectral Chicken")
  6ad0ad2bf8 ("x86/bugs: Report Intel retbleed vulnerability")
  c59a1f106f ("KVM: x86/pmu: Add IA32_PEBS_ENABLE MSR emulation for extended PEBS")
  465932db25 ("x86/cpu: Add new VMX feature, Tertiary VM-Execution control")
  027bbb884b ("KVM: x86/speculation: Disable Fill buffer clear within guests")
  5180218615 ("x86/speculation/mmio: Enumerate Processor MMIO Stale Data bug")

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	2022-08-17 09:05:13.938246475 -0300
  +++ after	2022-08-17 09:05:22.221455851 -0300
  @@ -161,6 +161,7 @@
   	[0x0000048f] = "IA32_VMX_TRUE_EXIT_CTLS",
   	[0x00000490] = "IA32_VMX_TRUE_ENTRY_CTLS",
   	[0x00000491] = "IA32_VMX_VMFUNC",
  +	[0x00000492] = "IA32_VMX_PROCBASED_CTLS3",
   	[0x000004c1] = "IA32_PMC0",
   	[0x000004d0] = "IA32_MCG_EXT_CTL",
   	[0x00000560] = "IA32_RTIT_OUTPUT_BASE",
  @@ -212,6 +213,7 @@
   	[0x0000064D] = "PLATFORM_ENERGY_STATUS",
   	[0x0000064e] = "PPERF",
   	[0x0000064f] = "PERF_LIMIT_REASONS",
  +	[0x00000650] = "SECONDARY_TURBO_RATIO_LIMIT",
   	[0x00000658] = "PKG_WEIGHTED_CORE_C0_RES",
   	[0x00000659] = "PKG_ANY_CORE_C0_RES",
   	[0x0000065A] = "PKG_ANY_GFXE_C0_RES",
  $

Now one can trace systemwide asking to see backtraces to where those
MSRs are 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 <adrian.hunter@intel.com>
Cc: Daniel Sneddon <daniel.sneddon@linux.intel.com>
Cc: Ian Rogers <irogers@google.com>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Len Brown <len.brown@intel.com>
Cc: Like Xu <like.xu@linux.intel.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Paolo Bonzini <pbonzini@redhat.com>
Cc: Pawan Gupta <pawan.kumar.gupta@linux.intel.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Robert Hoo <robert.hu@linux.intel.com>
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Link: https://lore.kernel.org/lkml/YvzbT24m2o5U%2F7+q@kernel.org/
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2022-08-19 15:30:33 -03:00
arch virtio: fixes 2022-08-17 08:58:54 -07:00
block block-6.0-2022-08-12 2022-08-13 13:37:36 -07:00
certs Kbuild updates for v5.20 2022-08-10 10:40:41 -07:00
crypto crypto: blake2b: effectively disable frame size warning 2022-08-10 17:59:11 -07:00
Documentation Including fixes from netfilter. 2022-08-18 19:37:15 -07:00
drivers Including fixes from netfilter. 2022-08-18 19:37:15 -07:00
fs ntfs3 for 6.0 2022-08-17 14:51:22 -07:00
include Including fixes from netfilter. 2022-08-18 19:37:15 -07:00
init Kbuild updates for v5.20 2022-08-10 10:40:41 -07:00
io_uring io_uring-6.0-2022-08-13 2022-08-13 13:28:54 -07:00
ipc Updates to various subsystems which I help look after. lib, ocfs2, 2022-08-07 10:03:24 -07:00
kernel Including fixes from netfilter. 2022-08-18 19:37:15 -07:00
lib lib: remove lib/nodemask.c 2022-08-12 09:07:33 -07:00
LICENSES LICENSES/LGPL-2.1: Add LGPL-2.1-or-later as valid identifiers 2021-12-16 14:33:10 +01:00
mm - hugetlb_vmemmap cleanups from Muchun Song 2022-08-10 11:18:00 -07:00
net tcp: handle pure FIN case correctly 2022-08-18 11:04:56 -07:00
samples Tracing updates for 5.20 / 6.0 2022-08-05 09:41:12 -07:00
scripts RISC-V Patches for the 5.20 Merge Window, Part 2 2022-08-12 18:39:43 -07:00
security + Features 2022-08-10 10:53:22 -07:00
sound sound fixes for 6.0-rc1 2022-08-12 09:55:32 -07:00
tools tools arch x86: Sync the msr-index.h copy with the kernel sources 2022-08-19 15:30:33 -03:00
usr Not a lot of material this cycle. Many singleton patches against various 2022-05-27 11:22:03 -07:00
virt KVM: Actually create debugfs in kvm_create_vm() 2022-08-10 15:08:28 -04:00
.clang-format PCI/DOE: Add DOE mailbox support functions 2022-07-19 15:38:04 -07:00
.cocciconfig scripts: add Linux .cocciconfig for coccinelle 2016-07-22 12:13:39 +02:00
.get_maintainer.ignore Opt out of scripts/get_maintainer.pl 2019-05-16 10:53:40 -07:00
.gitattributes .gitattributes: use 'dts' diff driver for dts files 2019-12-04 19:44:11 -08:00
.gitignore kbuild: split the second line of *.mod into *.usyms 2022-05-08 03:16:59 +09:00
.mailmap Updates to various subsystems which I help look after. lib, ocfs2, 2022-08-07 10:03:24 -07:00
COPYING COPYING: state that all contributions really are covered by this file 2020-02-10 13:32:20 -08:00
CREDITS drm for 5.20/6.0 2022-08-03 19:52:08 -07:00
Kbuild kbuild: rename hostprogs-y/always to hostprogs/always-y 2020-02-04 01:53:07 +09:00
Kconfig kbuild: ensure full rebuild when the compiler is updated 2020-05-12 13:28:33 +09:00
MAINTAINERS spi: Fixes for v6.0 2022-08-16 11:40:15 -07:00
Makefile Linux 6.0-rc1 2022-08-14 15:50:18 -07:00
README Drop all 00-INDEX files from Documentation/ 2018-09-09 15:08:58 -06:00

Linux kernel
============

There are several guides for kernel developers and users. These guides can
be rendered in a number of formats, like HTML and PDF. Please read
Documentation/admin-guide/README.rst first.

In order to build the documentation, use ``make htmldocs`` or
``make pdfdocs``.  The formatted documentation can also be read online at:

    https://www.kernel.org/doc/html/latest/

There are various text files in the Documentation/ subdirectory,
several of them using the Restructured Text markup notation.

Please read the Documentation/process/changes.rst file, as it contains the
requirements for building and running the kernel, and information about
the problems which may result by upgrading your kernel.