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<title>user/sven/linux.git/tools/arch, branch v6.1.87</title>
<subtitle>Linux Kernel
</subtitle>
<id>https://git.stealer.net/cgit.cgi/user/sven/linux.git/atom?h=v6.1.87</id>
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<updated>2024-02-23T08:12:28Z</updated>
<entry>
<title>work around gcc bugs with 'asm goto' with outputs</title>
<updated>2024-02-23T08:12:28Z</updated>
<author>
<name>Linus Torvalds</name>
<email>torvalds@linux-foundation.org</email>
</author>
<published>2024-02-09T20:39:31Z</published>
<link rel='alternate' type='text/html' href='https://git.stealer.net/cgit.cgi/user/sven/linux.git/commit/?id=f70efe54b97e95c369ab3f46cdbed8b5608e36d7'/>
<id>urn:sha1:f70efe54b97e95c369ab3f46cdbed8b5608e36d7</id>
<content type='text'>
commit 68fb3ca0e408e00db1c3f8fccdfa19e274c033be upstream.

We've had issues with gcc and 'asm goto' before, and we created a
'asm_volatile_goto()' macro for that in the past: see commits
3f0116c3238a ("compiler/gcc4: Add quirk for 'asm goto' miscompilation
bug") and a9f180345f53 ("compiler/gcc4: Make quirk for
asm_volatile_goto() unconditional").

Then, much later, we ended up removing the workaround in commit
43c249ea0b1e ("compiler-gcc.h: remove ancient workaround for gcc PR
58670") because we no longer supported building the kernel with the
affected gcc versions, but we left the macro uses around.

Now, Sean Christopherson reports a new version of a very similar
problem, which is fixed by re-applying that ancient workaround.  But the
problem in question is limited to only the 'asm goto with outputs'
cases, so instead of re-introducing the old workaround as-is, let's
rename and limit the workaround to just that much less common case.

It looks like there are at least two separate issues that all hit in
this area:

 (a) some versions of gcc don't mark the asm goto as 'volatile' when it
     has outputs:

        https://gcc.gnu.org/bugzilla/show_bug.cgi?id=98619
        https://gcc.gnu.org/bugzilla/show_bug.cgi?id=110420

     which is easy to work around by just adding the 'volatile' by hand.

 (b) Internal compiler errors:

        https://gcc.gnu.org/bugzilla/show_bug.cgi?id=110422

     which are worked around by adding the extra empty 'asm' as a
     barrier, as in the original workaround.

but the problem Sean sees may be a third thing since it involves bad
code generation (not an ICE) even with the manually added 'volatile'.

The same old workaround works for this case, even if this feels a
bit like voodoo programming and may only be hiding the issue.

Reported-and-tested-by: Sean Christopherson &lt;seanjc@google.com&gt;
Link: https://lore.kernel.org/all/20240208220604.140859-1-seanjc@google.com/
Cc: Nick Desaulniers &lt;ndesaulniers@google.com&gt;
Cc: Uros Bizjak &lt;ubizjak@gmail.com&gt;
Cc: Jakub Jelinek &lt;jakub@redhat.com&gt;
Cc: Andrew Pinski &lt;quic_apinski@quicinc.com&gt;
Signed-off-by: Linus Torvalds &lt;torvalds@linux-foundation.org&gt;
Signed-off-by: Greg Kroah-Hartman &lt;gregkh@linuxfoundation.org&gt;
</content>
</entry>
<entry>
<title>parisc: Drop the HP-UX ENOSYM and EREMOTERELEASE error codes</title>
<updated>2023-12-08T07:51:15Z</updated>
<author>
<name>Helge Deller</name>
<email>deller@gmx.de</email>
</author>
<published>2023-11-23T19:28:27Z</published>
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<id>urn:sha1:3793cd2ded7cd33a431a6764f1d13be30ac15d52</id>
<content type='text'>
commit e5f3e299a2b1e9c3ece24a38adfc089aef307e8a upstream.

Those return codes are only defined for the parisc architecture and
are leftovers from when we wanted to be HP-UX compatible.

They are not returned by any Linux kernel syscall but do trigger
problems with the glibc strerrorname_np() and strerror() functions as
reported in glibc issue #31080.

There is no need to keep them, so simply remove them.

Signed-off-by: Helge Deller &lt;deller@gmx.de&gt;
Reported-by: Bruno Haible &lt;bruno@clisp.org&gt;
Closes: https://sourceware.org/bugzilla/show_bug.cgi?id=31080
Cc: stable@vger.kernel.org
Signed-off-by: Greg Kroah-Hartman &lt;gregkh@linuxfoundation.org&gt;
</content>
</entry>
<entry>
<title>x86/bugs: Increase the x86 bugs vector size to two u32s</title>
<updated>2023-08-08T18:03:50Z</updated>
<author>
<name>Borislav Petkov (AMD)</name>
<email>bp@alien8.de</email>
</author>
<published>2023-07-08T08:21:35Z</published>
<link rel='alternate' type='text/html' href='https://git.stealer.net/cgit.cgi/user/sven/linux.git/commit/?id=dfede4cb8ef732039b7a479d260bd89d3b474f14'/>
<id>urn:sha1:dfede4cb8ef732039b7a479d260bd89d3b474f14</id>
<content type='text'>
Upstream commit: 0e52740ffd10c6c316837c6c128f460f1aaba1ea

There was never a doubt in my mind that they would not fit into a single
u32 eventually.

Signed-off-by: Borislav Petkov (AMD) &lt;bp@alien8.de&gt;
Signed-off-by: Greg Kroah-Hartman &lt;gregkh@linuxfoundation.org&gt;
</content>
</entry>
<entry>
<title>tools/x86/kcpuid: Fix avx512bw and avx512lvl fields in Fn00000007</title>
<updated>2023-05-11T14:03:07Z</updated>
<author>
<name>Terry Bowman</name>
<email>terry.bowman@amd.com</email>
</author>
<published>2023-02-06T14:18:30Z</published>
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<id>urn:sha1:f5222fbd797e8506c57f84a036b331cae83ab268</id>
<content type='text'>
[ Upstream commit 4e347bdf44c1fd4296a7b9657a2c0e1bd900fa50 ]

Leaf Fn00000007 contains avx512bw at bit 26 and avx512vl at bit 28. This
is incorrect per the SDM. Correct avx512bw to be bit 30 and avx512lvl to
be bit 31.

Fixes: c6b2f240bf8d ("tools/x86: Add a kcpuid tool to show raw CPU features")
Signed-off-by: Terry Bowman &lt;terry.bowman@amd.com&gt;
Signed-off-by: Borislav Petkov (AMD) &lt;bp@alien8.de&gt;
Reviewed-by: Feng Tang &lt;feng.tang@intel.com&gt;
Link: https://lore.kernel.org/r/20230206141832.4162264-2-terry.bowman@amd.com
Signed-off-by: Sasha Levin &lt;sashal@kernel.org&gt;
</content>
</entry>
<entry>
<title>parisc: Align parisc MADV_XXX constants with all other architectures</title>
<updated>2023-01-14T09:33:40Z</updated>
<author>
<name>Helge Deller</name>
<email>deller@gmx.de</email>
</author>
<published>2022-12-11T18:50:20Z</published>
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<id>urn:sha1:763b92568726b55569ea4896fe36e3c174cc3b0d</id>
<content type='text'>
commit 71bdea6f798b425bc0003780b13e3fdecb16a010 upstream.

Adjust some MADV_XXX constants to be in sync what their values are on
all other platforms. There is currently no reason to have an own
numbering on parisc, but it requires workarounds in many userspace
sources (e.g. glibc, qemu, ...) - which are often forgotten and thus
introduce bugs and different behaviour on parisc.

A wrapper avoids an ABI breakage for existing userspace applications by
translating any old values to the new ones, so this change allows us to
move over all programs to the new ABI over time.

Signed-off-by: Helge Deller &lt;deller@gmx.de&gt;
Signed-off-by: Greg Kroah-Hartman &lt;gregkh@linuxfoundation.org&gt;
</content>
</entry>
<entry>
<title>x86/cpu: Restore AMD's DE_CFG MSR after resume</title>
<updated>2022-11-15T18:15:58Z</updated>
<author>
<name>Borislav Petkov</name>
<email>bp@suse.de</email>
</author>
<published>2022-11-14T11:44:01Z</published>
<link rel='alternate' type='text/html' href='https://git.stealer.net/cgit.cgi/user/sven/linux.git/commit/?id=2632daebafd04746b4b96c2f26a6021bc38f6209'/>
<id>urn:sha1:2632daebafd04746b4b96c2f26a6021bc38f6209</id>
<content type='text'>
DE_CFG contains the LFENCE serializing bit, restore it on resume too.
This is relevant to older families due to the way how they do S3.

Unify and correct naming while at it.

Fixes: e4d0e84e4907 ("x86/cpu/AMD: Make LFENCE a serializing instruction")
Reported-by: Andrew Cooper &lt;Andrew.Cooper3@citrix.com&gt;
Reported-by: Pawan Gupta &lt;pawan.kumar.gupta@linux.intel.com&gt;
Signed-off-by: Borislav Petkov &lt;bp@suse.de&gt;
Cc: &lt;stable@kernel.org&gt;
Signed-off-by: Linus Torvalds &lt;torvalds@linux-foundation.org&gt;
</content>
</entry>
<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.stealer.net/cgit.cgi/user/sven/linux.git/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 headers: Update the copy of x86's memcpy_64.S used in 'perf bench'</title>
<updated>2022-10-25T20:40:48Z</updated>
<author>
<name>Arnaldo Carvalho de Melo</name>
<email>acme@redhat.com</email>
</author>
<published>2019-12-02T14:40:57Z</published>
<link rel='alternate' type='text/html' href='https://git.stealer.net/cgit.cgi/user/sven/linux.git/commit/?id=4402e360d0f833c8c67b2fda0d3f612f4fd8b2cc'/>
<id>urn:sha1:4402e360d0f833c8c67b2fda0d3f612f4fd8b2cc</id>
<content type='text'>
We also need to add SYM_TYPED_FUNC_START() to util/include/linux/linkage.h
and update tools/perf/check_headers.sh to ignore the include cfi_types.h
line when checking if the kernel original files drifted from the copies
we carry.

This is to get the changes from:

  ccace936eec7b805 ("x86: Add types to indirectly called assembly functions")

Addressing these tools/perf build warnings:

  Warning: Kernel ABI header at 'tools/arch/x86/lib/memcpy_64.S' differs from latest version at 'arch/x86/lib/memcpy_64.S'
  diff -u tools/arch/x86/lib/memcpy_64.S arch/x86/lib/memcpy_64.S

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: Kees Cook &lt;keescook@chromium.org&gt;
Cc: Sami Tolvanen &lt;samitolvanen@google.com&gt;
Link: https://lore.kernel.org/lkml/Y1f3VRIec9EBgX6F@kernel.org/
Signed-off-by: Arnaldo Carvalho de Melo &lt;acme@redhat.com&gt;
</content>
</entry>
<entry>
<title>tools headers arm64: Sync arm64's cputype.h 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>2022-04-09T14:48:15Z</published>
<link rel='alternate' type='text/html' href='https://git.stealer.net/cgit.cgi/user/sven/linux.git/commit/?id=ffc1df3dc97ee2aad6d2a94e4615c2a96cf291ad'/>
<id>urn:sha1:ffc1df3dc97ee2aad6d2a94e4615c2a96cf291ad</id>
<content type='text'>
To get the changes in:

  0e5d5ae837c8ce04 ("arm64: Add AMPERE1 to the Spectre-BHB affected list")

That addresses this perf build warning:

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

Cc: Catalin Marinas &lt;catalin.marinas@arm.com&gt;
Cc: D Scott Phillips &lt;scott@os.amperecomputing.com&gt;
https://lore.kernel.org/lkml/Y1fy5GD7ZYvkeufv@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.stealer.net/cgit.cgi/user/sven/linux.git/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>
</feed>
