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Arnaldo Carvalho de Melo 3442b5e05a tools arch x86: Sync the msr-index.h copy with the kernel sources
To pick up the changes in:

  dae1bd5838 ("x86/msr-index: Add MSRs for XFD")

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:

  $ diff -u tools/arch/x86/include/asm/msr-index.h arch/x86/include/asm/msr-index.h
  --- tools/arch/x86/include/asm/msr-index.h	2021-07-15 16:17:01.819817827 -0300
  +++ arch/x86/include/asm/msr-index.h	2021-11-06 15:49:33.738517311 -0300
  @@ -625,6 +625,8 @@

   #define MSR_IA32_BNDCFGS_RSVD		0x00000ffc

  +#define MSR_IA32_XFD			0x000001c4
  +#define MSR_IA32_XFD_ERR		0x000001c5
   #define MSR_IA32_XSS			0x00000da0

   #define MSR_IA32_APICBASE		0x0000001b
  $ tools/perf/trace/beauty/tracepoints/x86_msr.sh > /tmp/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 > /tmp/after
  $ diff -u /tmp/before /tmp/after
  --- /tmp/before	2021-11-13 11:10:39.964201505 -0300
  +++ /tmp/after	2021-11-13 11:10:47.902410873 -0300
  @@ -93,6 +93,8 @@
   	[0x000001b0] = "IA32_ENERGY_PERF_BIAS",
   	[0x000001b1] = "IA32_PACKAGE_THERM_STATUS",
   	[0x000001b2] = "IA32_PACKAGE_THERM_INTERRUPT",
  +	[0x000001c4] = "IA32_XFD",
  +	[0x000001c5] = "IA32_XFD_ERR",
   	[0x000001c8] = "LBR_SELECT",
   	[0x000001c9] = "LBR_TOS",
   	[0x000001d9] = "IA32_DEBUGCTLMSR",
  $

And this gets rebuilt:

  CC       /tmp/build/perf/trace/beauty/tracepoints/x86_msr.o
  INSTALL  trace_plugins
  LD       /tmp/build/perf/trace/beauty/tracepoints/perf-in.o
  LD       /tmp/build/perf/trace/beauty/perf-in.o
  LD       /tmp/build/perf/perf-in.o
  LINK     /tmp/build/perf/perf

Now one can trace systemwide asking to see backtraces to where those
MSRs are being read/written with:

  # perf trace -e msr:*_msr/max-stack=32/ --filter="msr==IA32_XFD || msr==IA32_XFD_ERR"
  ^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_XFD || msr==IA32_XFD_ERR"
  <SNIP>
  New filter for msr:read_msr: (msr==0x1c4 || msr==0x1c5) && (common_pid != 4448951 && common_pid != 8781)
  New filter for msr:write_msr: (msr==0x1c4 || msr==0x1c5) && (common_pid != 4448951 && common_pid != 8781)
  <SNIP>
  ^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 != 3738351 && common_pid != 3564)
  0x48
  New filter for msr:write_msr: (msr==0x48) && (common_pid != 3738351 && common_pid != 3564)
  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 pipewire/2479 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])
                                         schedule_hrtimeout_range_clock ([kernel.kallsyms])
                                         do_epoll_wait ([kernel.kallsyms])
                                         __x64_sys_epoll_wait ([kernel.kallsyms])
                                         do_syscall_64 ([kernel.kallsyms])
                                         entry_SYSCALL_64_after_hwframe ([kernel.kallsyms])
                                         epoll_wait (/usr/lib64/libc-2.33.so)
                                         [0x76c4] (/usr/lib64/spa-0.2/support/libspa-support.so)
                                         [0x4cf0] (/usr/lib64/spa-0.2/support/libspa-support.so)
       0.027 :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])
                                         start_kernel ([kernel.kallsyms])
                                         secondary_startup_64_no_verify ([kernel.kallsyms])
  #

Cc: Borislav Petkov <bp@suse.de>
Cc: Chang S. Bae <chang.seok.bae@intel.com>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Namhyung Kim <namhyung@kernel.org>
Link: https://lore.kernel.org/lkml/YY%2FJdb6on7swsn+C@kernel.org/
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2021-11-13 18:11:51 -03:00
arch Merge branch 'akpm' (patches from Andrew) 2021-11-11 14:31:47 -08:00
block for-5.16/drivers-2021-11-09 2021-11-09 11:24:08 -08:00
certs certs: Add support for using elliptic curve keys for signing modules 2021-08-23 19:55:42 +03:00
crypto Kbuild updates for v5.16 2021-11-08 09:15:45 -08:00
Documentation Merge branch 'akpm' (patches from Andrew) 2021-11-11 14:31:47 -08:00
drivers pci-v5.16-fixes-1 2021-11-11 15:10:18 -08:00
fs Networking fixes for 5.16-rc1, including fixes from bpf, can 2021-11-11 09:49:36 -08:00
include pci-v5.16-fixes-1 2021-11-11 15:10:18 -08:00
init mm: allow only SLUB on PREEMPT_RT 2021-11-11 09:34:35 -08:00
ipc ipc/ipc_sysctl.c: remove fallback for !CONFIG_PROC_SYSCTL 2021-11-09 10:02:53 -08:00
kernel KCSAN pull request for v5.16 2021-11-11 15:00:04 -08:00
lib mm/migrate.c: remove MIGRATE_PFN_LOCKED 2021-11-11 09:34:35 -08:00
LICENSES LICENSES/dual/CC-BY-4.0: Git rid of "smart quotes" 2021-07-15 06:31:24 -06:00
mm Merge branch 'akpm' (patches from Andrew) 2021-11-11 14:31:47 -08:00
net Networking fixes for 5.16-rc1, including fixes from bpf, can 2021-11-11 09:49:36 -08:00
samples Add gitignore file for samples/fanotify/ subdirectory 2021-11-07 11:19:24 -08:00
scripts Merge branch 'akpm' (patches from Andrew) 2021-11-09 10:11:53 -08:00
security + Features 2021-11-11 14:47:32 -08:00
sound TTY / Serial driver update for 5.16-rc1 2021-11-04 09:09:37 -07:00
tools tools arch x86: Sync the msr-index.h copy with the kernel sources 2021-11-13 18:11:51 -03:00
usr initramfs: Check timestamp to prevent broken cpio archive 2021-10-24 13:48:40 +09:00
virt kvm: irqfd: avoid update unmodified entries of the routing 2021-09-30 04:27:10 -04:00
.clang-format clang-format: Update with the latest for_each macro list 2021-05-12 23:32:39 +02:00
.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 .gitignore: ignore only top-level modules.builtin 2021-05-02 00:43:35 +09:00
.mailmap Merge branch 'akpm' (patches from Andrew) 2021-11-09 10:11:53 -08:00
COPYING COPYING: state that all contributions really are covered by this file 2020-02-10 13:32:20 -08:00
CREDITS MAINTAINERS: Move Daniel Drake to credits 2021-09-21 08:34:58 +03:00
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 Networking fixes for 5.16-rc1, including fixes from bpf, can 2021-11-11 09:49:36 -08:00
Makefile Kbuild updates for v5.16 2021-11-08 09:15:45 -08:00
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.