<feed xmlns='http://www.w3.org/2005/Atom'>
<title>linux-dev/tools/arch/x86/include, branch master</title>
<subtitle>Linux kernel development work - see feature branches</subtitle>
<id>https://git.zx2c4.com/linux-dev/atom/tools/arch/x86/include?h=master</id>
<link rel='self' href='https://git.zx2c4.com/linux-dev/atom/tools/arch/x86/include?h=master'/>
<link rel='alternate' type='text/html' href='https://git.zx2c4.com/linux-dev/'/>
<updated>2022-10-25T20:40:48Z</updated>
<entry>
<title>tools headers cpufeatures: Sync with the kernel sources</title>
<updated>2022-10-25T20:40:48Z</updated>
<author>
<name>Arnaldo Carvalho de Melo</name>
<email>acme@redhat.com</email>
</author>
<published>2021-07-01T16:39:15Z</published>
<link rel='alternate' type='text/html' href='https://git.zx2c4.com/linux-dev/commit/?id=74455fd7e459566198c8f1b2b33ca43a0c3ee8cb'/>
<id>urn:sha1:74455fd7e459566198c8f1b2b33ca43a0c3ee8cb</id>
<content type='text'>
To pick the changes from:

  257449c6a50298bd ("x86/cpufeatures: Add LbrExtV2 feature bit")

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 this perf build warning:

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

Cc: Adrian Hunter &lt;adrian.hunter@intel.com&gt;
Cc: Ian Rogers &lt;irogers@google.com&gt;
Cc: Jiri Olsa &lt;jolsa@kernel.org&gt;
Cc: Namhyung Kim &lt;namhyung@kernel.org&gt;
Cc: Peter Zijlstra &lt;peterz@infradead.org&gt;
Cc: Sandipan Das &lt;sandipan.das@amd.com&gt;
Link: https://lore.kernel.org/lkml/Y1g6vGPqPhOrXoaN@kernel.org
Signed-off-by: Arnaldo Carvalho de Melo &lt;acme@redhat.com&gt;
</content>
</entry>
<entry>
<title>tools arch x86: Sync the msr-index.h copy with the kernel sources</title>
<updated>2022-10-15T13:13:16Z</updated>
<author>
<name>Arnaldo Carvalho de Melo</name>
<email>acme@redhat.com</email>
</author>
<published>2020-08-07T11:45:47Z</published>
<link rel='alternate' type='text/html' href='https://git.zx2c4.com/linux-dev/commit/?id=a3a365655a28f12f07eddf4f3fd596987b175e1d'/>
<id>urn:sha1:a3a365655a28f12f07eddf4f3fd596987b175e1d</id>
<content type='text'>
To pick up the changes in:

  b8d1d163604bd1e6 ("x86/apic: Don't disable x2APIC if locked")
  ca5b7c0d9621702e ("perf/x86/amd/lbr: Add LbrExtV2 branch record support")

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 &gt; 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 &gt; after
  $ diff -u before after
  --- before	2022-10-14 18:06:34.294561729 -0300
  +++ after	2022-10-14 18:06:41.285744044 -0300
  @@ -264,6 +264,7 @@
   	[0xc0000102 - x86_64_specific_MSRs_offset] = "KERNEL_GS_BASE",
   	[0xc0000103 - x86_64_specific_MSRs_offset] = "TSC_AUX",
   	[0xc0000104 - x86_64_specific_MSRs_offset] = "AMD64_TSC_RATIO",
  +	[0xc000010e - x86_64_specific_MSRs_offset] = "AMD64_LBR_SELECT",
   	[0xc000010f - x86_64_specific_MSRs_offset] = "AMD_DBG_EXTN_CFG",
   	[0xc0000300 - x86_64_specific_MSRs_offset] = "AMD64_PERF_CNTR_GLOBAL_STATUS",
   	[0xc0000301 - x86_64_specific_MSRs_offset] = "AMD64_PERF_CNTR_GLOBAL_CTL",
  $

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&gt;=IA32_U_CET &amp;&amp; msr&lt;=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&gt;=IA32_U_CET &amp;&amp; msr&lt;=IA32_INT_SSP_TAB"
  Using CPUID AuthenticAMD-25-21-0
  0x6a0
  0x6a8
  New filter for msr:read_msr: (msr&gt;=0x6a0 &amp;&amp; msr&lt;=0x6a8) &amp;&amp; (common_pid != 597499 &amp;&amp; common_pid != 3313)
  0x6a0
  0x6a8
  New filter for msr:write_msr: (msr&gt;=0x6a0 &amp;&amp; msr&lt;=0x6a8) &amp;&amp; (common_pid != 597499 &amp;&amp; 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) &amp;&amp; (common_pid != 2612129 &amp;&amp; common_pid != 3841)
  0x48
  New filter for msr:write_msr: (msr==0x48) &amp;&amp; (common_pid != 2612129 &amp;&amp; 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 &lt;adrian.hunter@intel.com&gt;
Cc: Daniel Sneddon &lt;daniel.sneddon@linux.intel.com&gt;
Cc: Dave Hansen &lt;dave.hansen@linux.intel.com&gt;
Cc: Ian Rogers &lt;irogers@google.com&gt;
Cc: Jiri Olsa &lt;jolsa@kernel.org&gt;
Cc: Namhyung Kim &lt;namhyung@kernel.org&gt;
Cc: Peter Zijlstra &lt;peterz@infradead.org&gt;
Cc: Sandipan Das &lt;sandipan.das@amd.com&gt;
Link: https://lore.kernel.org/lkml/Y0nQkz2TUJxwfXJd@kernel.org
Signed-off-by: Arnaldo Carvalho de Melo &lt;acme@redhat.com&gt;
</content>
</entry>
<entry>
<title>perf amd ibs: Sync arch/x86/include/asm/amd-ibs.h header with the kernel</title>
<updated>2022-10-06T19:27:38Z</updated>
<author>
<name>Ravi Bangoria</name>
<email>ravi.bangoria@amd.com</email>
</author>
<published>2022-10-06T15:39:40Z</published>
<link rel='alternate' type='text/html' href='https://git.zx2c4.com/linux-dev/commit/?id=160ae99365abeac216aeaa3407dce6cf038037e1'/>
<id>urn:sha1:160ae99365abeac216aeaa3407dce6cf038037e1</id>
<content type='text'>
Although new details added into this header is currently used by kernel
only, tools copy needs to be in sync with kernel file to avoid
tools/perf/check-headers.sh warnings.

Signed-off-by: Ravi Bangoria &lt;ravi.bangoria@amd.com&gt;
Acked-by: Jiri Olsa &lt;jolsa@kernel.org&gt;
Cc: Alexander Shishkin &lt;alexander.shishkin@linux.intel.com&gt;
Cc: Ali Saidi &lt;alisaidi@amazon.com&gt;
Cc: Ananth Narayan &lt;ananth.narayan@amd.com&gt;
Cc: Andi Kleen &lt;ak@linux.intel.com&gt;
Cc: Borislav Petkov &lt;bp@alien8.de&gt;
Cc: Dave Hansen &lt;dave.hansen@linux.intel.com&gt;
Cc: H. Peter Anvin &lt;hpa@zytor.com&gt;
Cc: Ian Rogers &lt;irogers@google.com&gt;
Cc: Ingo Molnar &lt;mingo@redhat.com&gt;
Cc: Joe Mario &lt;jmario@redhat.com&gt;
Cc: Kan Liang &lt;kan.liang@linux.intel.com&gt;
Cc: Kim Phillips &lt;kim.phillips@amd.com&gt;
Cc: Leo Yan &lt;leo.yan@linaro.org&gt;
Cc: Mark Rutland &lt;mark.rutland@arm.com&gt;
Cc: Namhyung Kim &lt;namhyung@kernel.org&gt;
Cc: Peter Zijlstra &lt;peterz@infradead.org&gt;
Cc: Sandipan Das &lt;sandipan.das@amd.com&gt;
Cc: Santosh Shukla &lt;santosh.shukla@amd.com&gt;
Cc: Stephane Eranian &lt;eranian@google.com&gt;
Cc: Thomas Gleixner &lt;tglx@linutronix.de&gt;
Cc: x86@kernel.org
Link: https://lore.kernel.org/r/20221006153946.7816-3-ravi.bangoria@amd.com
Signed-off-by: Arnaldo Carvalho de Melo &lt;acme@redhat.com&gt;
</content>
</entry>
<entry>
<title>tools headers cpufeatures: Sync with the kernel sources</title>
<updated>2022-09-21T19:08:00Z</updated>
<author>
<name>Arnaldo Carvalho de Melo</name>
<email>acme@redhat.com</email>
</author>
<published>2021-07-01T16:39:15Z</published>
<link rel='alternate' type='text/html' href='https://git.zx2c4.com/linux-dev/commit/?id=356edeca2e811642b5848605c2f5f9a7c6c32112'/>
<id>urn:sha1:356edeca2e811642b5848605c2f5f9a7c6c32112</id>
<content type='text'>
To pick the changes from:

  7df548840c496b01 ("x86/bugs: Add "unknown" reporting for MMIO Stale Data")

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 this perf build warning:

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

Cc: Adrian Hunter &lt;adrian.hunter@intel.com&gt;
Cc: Borislav Petkov &lt;bp@suse.de&gt;
Cc: Ian Rogers &lt;irogers@google.com&gt;
Cc: Jiri Olsa &lt;jolsa@kernel.org&gt;
Cc: Namhyung Kim &lt;namhyung@kernel.org&gt;
Cc: Pawan Gupta &lt;pawan.kumar.gupta@linux.intel.com&gt;
Link: https://lore.kernel.org/lkml/YysTRji90sNn2p5f@kernel.org
Signed-off-by: Arnaldo Carvalho de Melo &lt;acme@redhat.com&gt;
</content>
</entry>
<entry>
<title>asm goto: eradicate CC_HAS_ASM_GOTO</title>
<updated>2022-08-21T17:06:28Z</updated>
<author>
<name>Nick Desaulniers</name>
<email>ndesaulniers@google.com</email>
</author>
<published>2022-08-19T19:06:40Z</published>
<link rel='alternate' type='text/html' href='https://git.zx2c4.com/linux-dev/commit/?id=a0a12c3ed057af57552bf6c0aeaca6835693df04'/>
<id>urn:sha1:a0a12c3ed057af57552bf6c0aeaca6835693df04</id>
<content type='text'>
GCC has supported asm goto since 4.5, and Clang has since version 9.0.0.
The minimum supported versions of these tools for the build according to
Documentation/process/changes.rst are 5.1 and 11.0.0 respectively.

Remove the feature detection script, Kconfig option, and clean up some
fallback code that is no longer supported.

The removed script was also testing for a GCC specific bug that was
fixed in the 4.7 release.

Also remove workarounds for bpftrace using clang older than 9.0.0, since
other BPF backend fixes are required at this point.

Link: https://lore.kernel.org/lkml/CAK7LNATSr=BXKfkdW8f-H5VT_w=xBpT2ZQcZ7rm6JfkdE+QnmA@mail.gmail.com/
Link: http://gcc.gnu.org/bugzilla/show_bug.cgi?id=48637
Acked-by: Borislav Petkov &lt;bp@suse.de&gt;
Suggested-by: Masahiro Yamada &lt;masahiroy@kernel.org&gt;
Suggested-by: Alexei Starovoitov &lt;alexei.starovoitov@gmail.com&gt;
Signed-off-by: Nick Desaulniers &lt;ndesaulniers@google.com&gt;
Reviewed-by: Ingo Molnar &lt;mingo@kernel.org&gt;
Reviewed-by: Nathan Chancellor &lt;nathan@kernel.org&gt;
Reviewed-by: Alexandre Belloni &lt;alexandre.belloni@bootlin.com&gt;
Signed-off-by: Linus Torvalds &lt;torvalds@linux-foundation.org&gt;
</content>
</entry>
<entry>
<title>tools headers UAPI: Sync x86's asm/kvm.h with the kernel sources</title>
<updated>2022-08-19T18:30:34Z</updated>
<author>
<name>Arnaldo Carvalho de Melo</name>
<email>acme@redhat.com</email>
</author>
<published>2021-09-10T14:46:54Z</published>
<link rel='alternate' type='text/html' href='https://git.zx2c4.com/linux-dev/commit/?id=e5bc0deae57615324ca843827873b39a34acc82e'/>
<id>urn:sha1:e5bc0deae57615324ca843827873b39a34acc82e</id>
<content type='text'>
To pick the changes in:

  43bb9e000ea4c621 ("KVM: x86: Tweak name of MONITOR/MWAIT #UD quirk to make it #UD specific")
  94dfc73e7cf4a31d ("treewide: uapi: Replace zero-length arrays with flexible-array members")
  bfbcc81bb82cbbad ("KVM: x86: Add a quirk for KVM's "MONITOR/MWAIT are NOPs!" behavior")
  b172862241b48499 ("KVM: x86: PIT: Preserve state of speaker port data bit")
  ed2351174e38ad4f ("KVM: x86: Extend KVM_{G,S}ET_VCPU_EVENTS to support pending triple fault")

That just rebuilds kvm-stat.c on x86, no change in functionality.

This silences these perf build warning:

  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

Cc: Chenyi Qiang &lt;chenyi.qiang@intel.com&gt;
Cc: Sean Christopherson &lt;seanjc@google.com&gt;
Cc: Gustavo A. R. Silva &lt;gustavoars@kernel.org&gt;
Cc: Paolo Bonzini &lt;pbonzini@redhat.com&gt;
Cc: Paul Durrant &lt;pdurrant@amazon.com&gt;
Link: https://lore.kernel.org/lkml/Yv6OMPKYqYSbUxwZ@kernel.org
Signed-off-by: Arnaldo Carvalho de Melo &lt;acme@redhat.com&gt;
</content>
</entry>
<entry>
<title>tools headers UAPI: Sync KVM's vmx.h header with the kernel sources</title>
<updated>2022-08-19T18:30:34Z</updated>
<author>
<name>Arnaldo Carvalho de Melo</name>
<email>acme@redhat.com</email>
</author>
<published>2021-03-02T20:20:08Z</published>
<link rel='alternate' type='text/html' href='https://git.zx2c4.com/linux-dev/commit/?id=eea085d11449bc6514dca9850cdd3a996ec1217e'/>
<id>urn:sha1:eea085d11449bc6514dca9850cdd3a996ec1217e</id>
<content type='text'>
To pick the changes in:

  2f4073e08f4cc5a4 ("KVM: VMX: Enable Notify VM exit")

That makes 'perf kvm-stat' aware of this new NOTIFY exit reason, thus
addressing the following perf build warning:

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

Cc: Adrian Hunter &lt;adrian.hunter@intel.com&gt;
Cc: Ian Rogers &lt;irogers@google.com&gt;
Cc: Jiri Olsa &lt;jolsa@kernel.org&gt;
Cc: Namhyung Kim &lt;namhyung@kernel.org&gt;
Cc: Paolo Bonzini &lt;pbonzini@redhat.com&gt;
Cc: Tao Xu &lt;tao3.xu@intel.com&gt;
Link: http://lore.kernel.org/lkml/Yv6LavXMZ+njijpq@kernel.org
Signed-off-by: Arnaldo Carvalho de Melo &lt;acme@redhat.com&gt;
</content>
</entry>
<entry>
<title>tools headers cpufeatures: Sync with the kernel sources</title>
<updated>2022-08-19T18:30:33Z</updated>
<author>
<name>Arnaldo Carvalho de Melo</name>
<email>acme@redhat.com</email>
</author>
<published>2021-07-01T16:39:15Z</published>
<link rel='alternate' type='text/html' href='https://git.zx2c4.com/linux-dev/commit/?id=62ed93d1996b3aaeadda59b25ac5b70be59b8a61'/>
<id>urn:sha1:62ed93d1996b3aaeadda59b25ac5b70be59b8a61</id>
<content type='text'>
To pick the changes from:

  2b1299322016731d ("x86/speculation: Add RSB VM Exit protections")
  28a99e95f55c6185 ("x86/amd: Use IBPB for firmware calls")
  4ad3278df6fe2b08 ("x86/speculation: Disable RRSBA behavior")
  26aae8ccbc197223 ("x86/cpu/amd: Enumerate BTC_NO")
  9756bba28470722d ("x86/speculation: Fill RSB on vmexit for IBRS")
  3ebc170068885b6f ("x86/bugs: Add retbleed=ibpb")
  2dbb887e875b1de3 ("x86/entry: Add kernel IBRS implementation")
  6b80b59b35557065 ("x86/bugs: Report AMD retbleed vulnerability")
  a149180fbcf336e9 ("x86: Add magic AMD return-thunk")
  15e67227c49a5783 ("x86: Undo return-thunk damage")
  a883d624aed463c8 ("x86/cpufeatures: Move RETPOLINE flags to word 11")
  aae99a7c9ab371b2 ("x86/cpufeatures: Introduce x2AVIC CPUID bit")
  6f33a9daff9f0790 ("x86: Fix comment for X86_FEATURE_ZEN")
  51802186158c74a0 ("x86/speculation/mmio: Enumerate Processor MMIO Stale Data bug")

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 this perf build warning:

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

Cc: Adrian Hunter &lt;adrian.hunter@intel.com&gt;
Cc: Alexandre Chartre &lt;alexandre.chartre@oracle.com&gt;
Cc: Andrew Cooper &lt;andrew.cooper3@citrix.com&gt;
Cc: Borislav Petkov &lt;bp@suse.de&gt;
Cc: Daniel Sneddon &lt;daniel.sneddon@linux.intel.com&gt;
Cc: Dave Hansen &lt;dave.hansen@linux.intel.com&gt;
Cc: Ian Rogers &lt;irogers@google.com&gt;
Cc: Jiri Olsa &lt;jolsa@kernel.org&gt;
Cc: Josh Poimboeuf &lt;jpoimboe@kernel.org&gt;
Cc: Namhyung Kim &lt;namhyung@kernel.org&gt;
Cc: Paolo Bonzini &lt;pbonzini@redhat.com&gt;
Cc: Pawan Gupta &lt;pawan.kumar.gupta@linux.intel.com&gt;
Cc: Peter Zijlstra &lt;peterz@infradead.org&gt;
Cc: Suravee Suthikulpanit &lt;suravee.suthikulpanit@amd.com&gt;
Cc: Wyes Karny &lt;wyes.karny@amd.com&gt;
Link: https://lore.kernel.org/lkml/Yvznmu5oHv0ZDN2w@kernel.org
Signed-off-by: Arnaldo Carvalho de Melo &lt;acme@redhat.com&gt;
</content>
</entry>
<entry>
<title>tools arch x86: Sync the msr-index.h copy with the kernel sources</title>
<updated>2022-08-19T18:30:33Z</updated>
<author>
<name>Arnaldo Carvalho de Melo</name>
<email>acme@redhat.com</email>
</author>
<published>2020-08-07T11:45:47Z</published>
<link rel='alternate' type='text/html' href='https://git.zx2c4.com/linux-dev/commit/?id=7f7f86a7bdd694bfb214479afb6a1f7266bb4d22'/>
<id>urn:sha1:7f7f86a7bdd694bfb214479afb6a1f7266bb4d22</id>
<content type='text'>
To pick up the changes in:

  2b1299322016731d ("x86/speculation: Add RSB VM Exit protections")
  4af184ee8b2c0a69 ("tools/power turbostat: dump secondary Turbo-Ratio-Limit")
  4ad3278df6fe2b08 ("x86/speculation: Disable RRSBA behavior")
  d7caac991feeef1b ("x86/cpu/amd: Add Spectral Chicken")
  6ad0ad2bf8a67e27 ("x86/bugs: Report Intel retbleed vulnerability")
  c59a1f106f5cd484 ("KVM: x86/pmu: Add IA32_PEBS_ENABLE MSR emulation for extended PEBS")
  465932db25f36648 ("x86/cpu: Add new VMX feature, Tertiary VM-Execution control")
  027bbb884be006b0 ("KVM: x86/speculation: Disable Fill buffer clear within guests")
  51802186158c74a0 ("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 &gt; 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 &gt; 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&gt;=IA32_U_CET &amp;&amp; msr&lt;=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&gt;=IA32_U_CET &amp;&amp; msr&lt;=IA32_INT_SSP_TAB"
  Using CPUID AuthenticAMD-25-21-0
  0x6a0
  0x6a8
  New filter for msr:read_msr: (msr&gt;=0x6a0 &amp;&amp; msr&lt;=0x6a8) &amp;&amp; (common_pid != 597499 &amp;&amp; common_pid != 3313)
  0x6a0
  0x6a8
  New filter for msr:write_msr: (msr&gt;=0x6a0 &amp;&amp; msr&lt;=0x6a8) &amp;&amp; (common_pid != 597499 &amp;&amp; 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) &amp;&amp; (common_pid != 2612129 &amp;&amp; common_pid != 3841)
  0x48
  New filter for msr:write_msr: (msr==0x48) &amp;&amp; (common_pid != 2612129 &amp;&amp; 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 &lt;adrian.hunter@intel.com&gt;
Cc: Daniel Sneddon &lt;daniel.sneddon@linux.intel.com&gt;
Cc: Ian Rogers &lt;irogers@google.com&gt;
Cc: Jiri Olsa &lt;jolsa@kernel.org&gt;
Cc: Len Brown &lt;len.brown@intel.com&gt;
Cc: Like Xu &lt;like.xu@linux.intel.com&gt;
Cc: Namhyung Kim &lt;namhyung@kernel.org&gt;
Cc: Paolo Bonzini &lt;pbonzini@redhat.com&gt;
Cc: Pawan Gupta &lt;pawan.kumar.gupta@linux.intel.com&gt;
Cc: Peter Zijlstra &lt;peterz@infradead.org&gt;
Cc: Robert Hoo &lt;robert.hu@linux.intel.com&gt;
Signed-off-by: Arnaldo Carvalho de Melo &lt;acme@redhat.com&gt;
Link: https://lore.kernel.org/lkml/YvzbT24m2o5U%2F7+q@kernel.org/
Signed-off-by: Arnaldo Carvalho de Melo &lt;acme@redhat.com&gt;
</content>
</entry>
<entry>
<title>Merge tag 'x86_bugs_pbrsb' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip</title>
<updated>2022-08-09T16:29:07Z</updated>
<author>
<name>Linus Torvalds</name>
<email>torvalds@linux-foundation.org</email>
</author>
<published>2022-08-09T16:29:07Z</published>
<link rel='alternate' type='text/html' href='https://git.zx2c4.com/linux-dev/commit/?id=5318b987fe9f3430adb0f5d81d07052fd996835b'/>
<id>urn:sha1:5318b987fe9f3430adb0f5d81d07052fd996835b</id>
<content type='text'>
Pull x86 eIBRS fixes from Borislav Petkov:
 "More from the CPU vulnerability nightmares front:

  Intel eIBRS machines do not sufficiently mitigate against RET
  mispredictions when doing a VM Exit therefore an additional RSB,
  one-entry stuffing is needed"

* tag 'x86_bugs_pbrsb' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  x86/speculation: Add LFENCE to RSB fill sequence
  x86/speculation: Add RSB VM Exit protections
</content>
</entry>
</feed>
