<feed xmlns='http://www.w3.org/2005/Atom'>
<title>linux-toradex.git/tools/arch, branch v6.15-rc4</title>
<subtitle>Linux kernel for Apalis and Colibri modules</subtitle>
<link rel='alternate' type='text/html' href='https://git.toradex.cn/cgit/linux-toradex.git/'/>
<entry>
<title>x86/insn: Fix CTEST instruction decoding</title>
<updated>2025-04-24T18:19:17+00:00</updated>
<author>
<name>Kirill A. Shutemov</name>
<email>kirill.shutemov@linux.intel.com</email>
</author>
<published>2025-04-23T06:58:15+00:00</published>
<link rel='alternate' type='text/html' href='https://git.toradex.cn/cgit/linux-toradex.git/commit/?id=85fd85bc025a525354acb2241beb3c5387c551ec'/>
<id>85fd85bc025a525354acb2241beb3c5387c551ec</id>
<content type='text'>
insn_decoder_test found a problem with decoding APX CTEST instructions:

	Found an x86 instruction decoder bug, please report this.
	ffffffff810021df	62 54 94 05 85 ff    	ctestneq
	objdump says 6 bytes, but insn_get_length() says 5

It happens because x86-opcode-map.txt doesn't specify arguments for the
instruction and the decoder doesn't expect to see ModRM byte.

Fixes: 690ca3a3067f ("x86/insn: Add support for APX EVEX instructions to the opcode map")
Signed-off-by: Kirill A. Shutemov &lt;kirill.shutemov@linux.intel.com&gt;
Signed-off-by: Ingo Molnar &lt;mingo@kernel.org&gt;
Cc: H. Peter Anvin &lt;hpa@zytor.com&gt;
Cc: Adrian Hunter &lt;adrian.hunter@intel.com&gt;
Cc: stable@vger.kernel.org # v6.10+
Link: https://lore.kernel.org/r/20250423065815.2003231-1-kirill.shutemov@linux.intel.com
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
insn_decoder_test found a problem with decoding APX CTEST instructions:

	Found an x86 instruction decoder bug, please report this.
	ffffffff810021df	62 54 94 05 85 ff    	ctestneq
	objdump says 6 bytes, but insn_get_length() says 5

It happens because x86-opcode-map.txt doesn't specify arguments for the
instruction and the decoder doesn't expect to see ModRM byte.

Fixes: 690ca3a3067f ("x86/insn: Add support for APX EVEX instructions to the opcode map")
Signed-off-by: Kirill A. Shutemov &lt;kirill.shutemov@linux.intel.com&gt;
Signed-off-by: Ingo Molnar &lt;mingo@kernel.org&gt;
Cc: H. Peter Anvin &lt;hpa@zytor.com&gt;
Cc: Adrian Hunter &lt;adrian.hunter@intel.com&gt;
Cc: stable@vger.kernel.org # v6.10+
Link: https://lore.kernel.org/r/20250423065815.2003231-1-kirill.shutemov@linux.intel.com
</pre>
</div>
</content>
</entry>
<entry>
<title>tools headers: Update the arch/x86/lib/memset_64.S copy with the kernel sources</title>
<updated>2025-04-10T16:28:25+00:00</updated>
<author>
<name>Namhyung Kim</name>
<email>namhyung@kernel.org</email>
</author>
<published>2025-04-10T00:11:25+00:00</published>
<link rel='alternate' type='text/html' href='https://git.toradex.cn/cgit/linux-toradex.git/commit/?id=7f56978e5876521eaa90fda0e63630fa64f69bce'/>
<id>7f56978e5876521eaa90fda0e63630fa64f69bce</id>
<content type='text'>
To pick up the changes in:

  2981557cb0408e14 x86,kcfi: Fix EXPORT_SYMBOL vs kCFI

That required adding a copy of include/linux/cfi_types.h and its checking
in tools/perf/check-headers.h.

Addressing this perf tools build warning:

  Warning: Kernel ABI header differences:
    diff -u tools/arch/x86/lib/memset_64.S arch/x86/lib/memset_64.S

Please see tools/include/uapi/README for further details.

Acked-by: Ingo Molnar &lt;mingo@kernel.org&gt;
Tested-by: Venkat Rao Bagalkote &lt;venkat88@linux.ibm.com&gt;
Cc: x86@kernel.org
Link: https://lore.kernel.org/r/20250410001125.391820-11-namhyung@kernel.org
Signed-off-by: Namhyung Kim &lt;namhyung@kernel.org&gt;
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
To pick up the changes in:

  2981557cb0408e14 x86,kcfi: Fix EXPORT_SYMBOL vs kCFI

That required adding a copy of include/linux/cfi_types.h and its checking
in tools/perf/check-headers.h.

Addressing this perf tools build warning:

  Warning: Kernel ABI header differences:
    diff -u tools/arch/x86/lib/memset_64.S arch/x86/lib/memset_64.S

Please see tools/include/uapi/README for further details.

Acked-by: Ingo Molnar &lt;mingo@kernel.org&gt;
Tested-by: Venkat Rao Bagalkote &lt;venkat88@linux.ibm.com&gt;
Cc: x86@kernel.org
Link: https://lore.kernel.org/r/20250410001125.391820-11-namhyung@kernel.org
Signed-off-by: Namhyung Kim &lt;namhyung@kernel.org&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>tools headers: Update the x86 headers with the kernel sources</title>
<updated>2025-04-10T16:28:25+00:00</updated>
<author>
<name>Namhyung Kim</name>
<email>namhyung@kernel.org</email>
</author>
<published>2025-04-10T00:11:24+00:00</published>
<link rel='alternate' type='text/html' href='https://git.toradex.cn/cgit/linux-toradex.git/commit/?id=847f1403d3ee51278dfbece84ec7f199de43daa5'/>
<id>847f1403d3ee51278dfbece84ec7f199de43daa5</id>
<content type='text'>
To pick up the changes in:

  841326332bcb13ae x86/cpufeatures: Generate the &lt;asm/cpufeaturemasks.h&gt; header based on build config
  440a65b7d25fb06f x86/mm: Enable AMD translation cache extensions
  767ae437a32d6447 x86/mm: Add INVLPGB feature and Kconfig entry
  b4cc466b97359011 cpufreq/amd-pstate: Replace all AMD_CPPC_* macros with masks
  98c7a713db91c5a9 x86/bugs: Add X86_BUG_SPECTRE_V2_USER
  8f64eee70cdd3bb8 x86/bugs: Remove X86_FEATURE_USE_IBPB
  8442df2b49ed9bcd x86/bugs: KVM: Add support for SRSO_MSR_FIX
  70792aed14551e31 x86/cpufeatures: Add CPUID feature bit for Idle HLT intercept
  968e9bc4cef87054 x86: move ZMM exclusion list into CPU feature flag
  c631a2de7ae48d50 perf/x86/intel: Ensure LBRs are disabled when a CPU is starting
  38cc6495cdec18a4 x86/sev: Prevent GUEST_TSC_FREQ MSR interception for Secure TSC enabled guests
  288bba2f4c8be1e1 x86/cpufeatures: Remove "AMD" from the comments to the AMD-specific leaf
  877818802c3e970f x86/bugs: Add SRSO_USER_KERNEL_NO support
  8ae3291f773befee x86/sev: Add full support for a segmented RMP table
  0cbc0258415814c8 x86/sev: Add support for the RMPREAD instruction
  7a470e826d7521be x86/cpufeatures: Free up unused feature bits

Addressing this perf tools build warning:

  Warning: Kernel ABI header differences:
    diff -u tools/arch/x86/include/asm/cpufeatures.h arch/x86/include/asm/cpufeatures.h
    diff -u tools/arch/x86/include/asm/msr-index.h arch/x86/include/asm/msr-index.h

Please see tools/include/uapi/README for further details.

Acked-by: Ingo Molnar &lt;mingo@kernel.org&gt;
Tested-by: Venkat Rao Bagalkote &lt;venkat88@linux.ibm.com&gt;
Cc: x86@kernel.org
Link: https://lore.kernel.org/r/20250410001125.391820-10-namhyung@kernel.org
Signed-off-by: Namhyung Kim &lt;namhyung@kernel.org&gt;
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
To pick up the changes in:

  841326332bcb13ae x86/cpufeatures: Generate the &lt;asm/cpufeaturemasks.h&gt; header based on build config
  440a65b7d25fb06f x86/mm: Enable AMD translation cache extensions
  767ae437a32d6447 x86/mm: Add INVLPGB feature and Kconfig entry
  b4cc466b97359011 cpufreq/amd-pstate: Replace all AMD_CPPC_* macros with masks
  98c7a713db91c5a9 x86/bugs: Add X86_BUG_SPECTRE_V2_USER
  8f64eee70cdd3bb8 x86/bugs: Remove X86_FEATURE_USE_IBPB
  8442df2b49ed9bcd x86/bugs: KVM: Add support for SRSO_MSR_FIX
  70792aed14551e31 x86/cpufeatures: Add CPUID feature bit for Idle HLT intercept
  968e9bc4cef87054 x86: move ZMM exclusion list into CPU feature flag
  c631a2de7ae48d50 perf/x86/intel: Ensure LBRs are disabled when a CPU is starting
  38cc6495cdec18a4 x86/sev: Prevent GUEST_TSC_FREQ MSR interception for Secure TSC enabled guests
  288bba2f4c8be1e1 x86/cpufeatures: Remove "AMD" from the comments to the AMD-specific leaf
  877818802c3e970f x86/bugs: Add SRSO_USER_KERNEL_NO support
  8ae3291f773befee x86/sev: Add full support for a segmented RMP table
  0cbc0258415814c8 x86/sev: Add support for the RMPREAD instruction
  7a470e826d7521be x86/cpufeatures: Free up unused feature bits

Addressing this perf tools build warning:

  Warning: Kernel ABI header differences:
    diff -u tools/arch/x86/include/asm/cpufeatures.h arch/x86/include/asm/cpufeatures.h
    diff -u tools/arch/x86/include/asm/msr-index.h arch/x86/include/asm/msr-index.h

Please see tools/include/uapi/README for further details.

Acked-by: Ingo Molnar &lt;mingo@kernel.org&gt;
Tested-by: Venkat Rao Bagalkote &lt;venkat88@linux.ibm.com&gt;
Cc: x86@kernel.org
Link: https://lore.kernel.org/r/20250410001125.391820-10-namhyung@kernel.org
Signed-off-by: Namhyung Kim &lt;namhyung@kernel.org&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>tools headers: Update the syscall table with the kernel sources</title>
<updated>2025-04-10T16:28:24+00:00</updated>
<author>
<name>Namhyung Kim</name>
<email>namhyung@kernel.org</email>
</author>
<published>2025-04-10T00:11:20+00:00</published>
<link rel='alternate' type='text/html' href='https://git.toradex.cn/cgit/linux-toradex.git/commit/?id=22f72088ffe69a375e07020795264faaaa175979'/>
<id>22f72088ffe69a375e07020795264faaaa175979</id>
<content type='text'>
To pick up the changes in:

  c4a16820d9019940 fs: add open_tree_attr()
  2df1ad0d25803399 x86/arch_prctl: Simplify sys_arch_prctl()
  e632bca07c8eef1d arm64: generate 64-bit syscall.tbl

This is basically to support the new open_tree_attr syscall.  But it
also needs to update asm-generic unistd.h header to get the new syscall
number.  And arm64 unistd.h header was converted to use the generic
64-bit header.

Addressing this perf tools build warning:

  Warning: Kernel ABI header differences:
    diff -u tools/scripts/syscall.tbl scripts/syscall.tbl
    diff -u tools/perf/arch/x86/entry/syscalls/syscall_32.tbl arch/x86/entry/syscalls/syscall_32.tbl
    diff -u tools/perf/arch/x86/entry/syscalls/syscall_64.tbl arch/x86/entry/syscalls/syscall_64.tbl
    diff -u tools/perf/arch/powerpc/entry/syscalls/syscall.tbl arch/powerpc/kernel/syscalls/syscall.tbl
    diff -u tools/perf/arch/s390/entry/syscalls/syscall.tbl arch/s390/kernel/syscalls/syscall.tbl
    diff -u tools/perf/arch/mips/entry/syscalls/syscall_n64.tbl arch/mips/kernel/syscalls/syscall_n64.tbl
    diff -u tools/perf/arch/arm/entry/syscalls/syscall.tbl arch/arm/tools/syscall.tbl
    diff -u tools/perf/arch/sh/entry/syscalls/syscall.tbl arch/sh/kernel/syscalls/syscall.tbl
    diff -u tools/perf/arch/sparc/entry/syscalls/syscall.tbl arch/sparc/kernel/syscalls/syscall.tbl
    diff -u tools/perf/arch/xtensa/entry/syscalls/syscall.tbl arch/xtensa/kernel/syscalls/syscall.tbl
    diff -u tools/arch/arm64/include/uapi/asm/unistd.h arch/arm64/include/uapi/asm/unistd.h
    diff -u tools/include/uapi/asm-generic/unistd.h include/uapi/asm-generic/unistd.h

Please see tools/include/uapi/README for further details.

Acked-by: Ingo Molnar &lt;mingo@kernel.org&gt;
Tested-by: Venkat Rao Bagalkote &lt;venkat88@linux.ibm.com&gt;
Cc: linux-arch@vger.kernel.org
Link: https://lore.kernel.org/r/20250410001125.391820-6-namhyung@kernel.org
Signed-off-by: Namhyung Kim &lt;namhyung@kernel.org&gt;
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
To pick up the changes in:

  c4a16820d9019940 fs: add open_tree_attr()
  2df1ad0d25803399 x86/arch_prctl: Simplify sys_arch_prctl()
  e632bca07c8eef1d arm64: generate 64-bit syscall.tbl

This is basically to support the new open_tree_attr syscall.  But it
also needs to update asm-generic unistd.h header to get the new syscall
number.  And arm64 unistd.h header was converted to use the generic
64-bit header.

Addressing this perf tools build warning:

  Warning: Kernel ABI header differences:
    diff -u tools/scripts/syscall.tbl scripts/syscall.tbl
    diff -u tools/perf/arch/x86/entry/syscalls/syscall_32.tbl arch/x86/entry/syscalls/syscall_32.tbl
    diff -u tools/perf/arch/x86/entry/syscalls/syscall_64.tbl arch/x86/entry/syscalls/syscall_64.tbl
    diff -u tools/perf/arch/powerpc/entry/syscalls/syscall.tbl arch/powerpc/kernel/syscalls/syscall.tbl
    diff -u tools/perf/arch/s390/entry/syscalls/syscall.tbl arch/s390/kernel/syscalls/syscall.tbl
    diff -u tools/perf/arch/mips/entry/syscalls/syscall_n64.tbl arch/mips/kernel/syscalls/syscall_n64.tbl
    diff -u tools/perf/arch/arm/entry/syscalls/syscall.tbl arch/arm/tools/syscall.tbl
    diff -u tools/perf/arch/sh/entry/syscalls/syscall.tbl arch/sh/kernel/syscalls/syscall.tbl
    diff -u tools/perf/arch/sparc/entry/syscalls/syscall.tbl arch/sparc/kernel/syscalls/syscall.tbl
    diff -u tools/perf/arch/xtensa/entry/syscalls/syscall.tbl arch/xtensa/kernel/syscalls/syscall.tbl
    diff -u tools/arch/arm64/include/uapi/asm/unistd.h arch/arm64/include/uapi/asm/unistd.h
    diff -u tools/include/uapi/asm-generic/unistd.h include/uapi/asm-generic/unistd.h

Please see tools/include/uapi/README for further details.

Acked-by: Ingo Molnar &lt;mingo@kernel.org&gt;
Tested-by: Venkat Rao Bagalkote &lt;venkat88@linux.ibm.com&gt;
Cc: linux-arch@vger.kernel.org
Link: https://lore.kernel.org/r/20250410001125.391820-6-namhyung@kernel.org
Signed-off-by: Namhyung Kim &lt;namhyung@kernel.org&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>tools headers: Update the KVM headers with the kernel sources</title>
<updated>2025-04-10T16:28:24+00:00</updated>
<author>
<name>Namhyung Kim</name>
<email>namhyung@kernel.org</email>
</author>
<published>2025-04-10T00:11:16+00:00</published>
<link rel='alternate' type='text/html' href='https://git.toradex.cn/cgit/linux-toradex.git/commit/?id=ddc592972ff4f1350f456edc3047fc5fb01777aa'/>
<id>ddc592972ff4f1350f456edc3047fc5fb01777aa</id>
<content type='text'>
To pick up the changes in:

  af5366bea2cb9dfb KVM: x86: Drop the now unused KVM_X86_DISABLE_VALID_EXITS
  915d2f0718a42ee0 KVM: Move KVM_REG_SIZE() definition to common uAPI header
  5c17848134ab1ffb KVM: x86/xen: Restrict hypercall MSR to unofficial synthetic range
  9364789567f9b492 KVM: x86: Add a VM type define for TDX
  fa662c9080732b1f KVM: SVM: Add Idle HLT intercept support
  3adaee78306148da KVM: arm64: Allow userspace to change the implementation ID registers
  faf7714a47a25c62 KVM: arm64: nv: Allow userland to set VGIC maintenance IRQ
  c0000e58c74eed07 KVM: arm64: Introduce KVM_REG_ARM_VENDOR_HYP_BMAP_2
  f83c41fb3dddbf47 KVM: arm64: Allow userspace to limit NV support to nVHE

Addressing this perf tools build warning:

  Warning: Kernel ABI header differences:
    diff -u tools/include/uapi/linux/kvm.h include/uapi/linux/kvm.h
    diff -u tools/arch/x86/include/uapi/asm/kvm.h arch/x86/include/uapi/asm/kvm.h
    diff -u tools/arch/x86/include/uapi/asm/svm.h arch/x86/include/uapi/asm/svm.h
    diff -u tools/arch/arm64/include/uapi/asm/kvm.h arch/arm64/include/uapi/asm/kvm.h

Please see tools/include/uapi/README for further details.

Acked-by: Ingo Molnar &lt;mingo@kernel.org&gt;
Tested-by: Venkat Rao Bagalkote &lt;venkat88@linux.ibm.com&gt;
Cc: kvm@vger.kernel.org
Link: https://lore.kernel.org/r/20250410001125.391820-2-namhyung@kernel.org
Signed-off-by: Namhyung Kim &lt;namhyung@kernel.org&gt;
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
To pick up the changes in:

  af5366bea2cb9dfb KVM: x86: Drop the now unused KVM_X86_DISABLE_VALID_EXITS
  915d2f0718a42ee0 KVM: Move KVM_REG_SIZE() definition to common uAPI header
  5c17848134ab1ffb KVM: x86/xen: Restrict hypercall MSR to unofficial synthetic range
  9364789567f9b492 KVM: x86: Add a VM type define for TDX
  fa662c9080732b1f KVM: SVM: Add Idle HLT intercept support
  3adaee78306148da KVM: arm64: Allow userspace to change the implementation ID registers
  faf7714a47a25c62 KVM: arm64: nv: Allow userland to set VGIC maintenance IRQ
  c0000e58c74eed07 KVM: arm64: Introduce KVM_REG_ARM_VENDOR_HYP_BMAP_2
  f83c41fb3dddbf47 KVM: arm64: Allow userspace to limit NV support to nVHE

Addressing this perf tools build warning:

  Warning: Kernel ABI header differences:
    diff -u tools/include/uapi/linux/kvm.h include/uapi/linux/kvm.h
    diff -u tools/arch/x86/include/uapi/asm/kvm.h arch/x86/include/uapi/asm/kvm.h
    diff -u tools/arch/x86/include/uapi/asm/svm.h arch/x86/include/uapi/asm/svm.h
    diff -u tools/arch/arm64/include/uapi/asm/kvm.h arch/arm64/include/uapi/asm/kvm.h

Please see tools/include/uapi/README for further details.

Acked-by: Ingo Molnar &lt;mingo@kernel.org&gt;
Tested-by: Venkat Rao Bagalkote &lt;venkat88@linux.ibm.com&gt;
Cc: kvm@vger.kernel.org
Link: https://lore.kernel.org/r/20250410001125.391820-2-namhyung@kernel.org
Signed-off-by: Namhyung Kim &lt;namhyung@kernel.org&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>Merge tag 'perf-tools-for-v6.15-2025-03-27' of git://git.kernel.org/pub/scm/linux/kernel/git/perf/perf-tools</title>
<updated>2025-03-31T15:52:33+00:00</updated>
<author>
<name>Linus Torvalds</name>
<email>torvalds@linux-foundation.org</email>
</author>
<published>2025-03-31T15:52:33+00:00</published>
<link rel='alternate' type='text/html' href='https://git.toradex.cn/cgit/linux-toradex.git/commit/?id=802f0d58d52e8e34e08718479475ccdff0caffa0'/>
<id>802f0d58d52e8e34e08718479475ccdff0caffa0</id>
<content type='text'>
Pull perf tools updates from Namhyung Kim:
 "perf record:

   - Introduce latency profiling using scheduler information.

     The latency profiling is to show impacts on wall-time rather than
     cpu-time. By tracking context switches, it can weight samples and
     find which part of the code contributed more to the execution
     latency.

     The value (period) of the sample is weighted by dividing it by the
     number of parallel execution at the moment. The parallelism is
     tracked in perf report with sched-switch records. This will reduce
     the portion that are run in parallel and in turn increase the
     portion of serial executions.

     For now, it's limited to profile processes, IOW system-wide
     profiling is not supported. You can add --latency option to enable
     this.

       $ perf record --latency -- make -C tools/perf

     I've run the above command for perf build which adds -j option to
     make with the number of CPUs in the system internally. Normally
     it'd show something like below:

       $ perf report -F overhead,comm
       ...
       #
       # Overhead  Command
       # ........  ...............
       #
           78.97%  cc1
            6.54%  python3
            4.21%  shellcheck
            3.28%  ld
            1.80%  as
            1.37%  cc1plus
            0.80%  sh
            0.62%  clang
            0.56%  gcc
            0.44%  perl
            0.39%  make
  	 ...

     The cc1 takes around 80% of the overhead as it's the actual
     compiler. However it runs in parallel so its contribution to
     latency may be less than that. Now, perf report will show both
     overhead and latency (if --latency was given at record time) like
     below:

       $ perf report -s comm
       ...
       #
       # Overhead   Latency  Command
       # ........  ........  ...............
       #
           78.97%    48.66%  cc1
            6.54%    25.68%  python3
            4.21%     0.39%  shellcheck
            3.28%    13.70%  ld
            1.80%     2.56%  as
            1.37%     3.08%  cc1plus
            0.80%     0.98%  sh
            0.62%     0.61%  clang
            0.56%     0.33%  gcc
            0.44%     1.71%  perl
            0.39%     0.83%  make
  	 ...

     You can see latency of cc1 goes down to around 50% and python3 and
     ld contribute a lot more than their overhead. You can use --latency
     option in perf report to get the same result but ordered by
     latency.

       $ perf report --latency -s comm

  perf report:

   - As a side effect of the latency profiling work, it adds a new
     output field 'latency' and a sort key 'parallelism'. The below is a
     result from my system with 64 CPUs. The build was well-parallelized
     but contained some serial portions.

       $ perf report -s parallelism
       ...
       #
       # Overhead   Latency  Parallelism
       # ........  ........  ...........
       #
           16.95%     1.54%           62
           13.38%     1.24%           61
           12.50%    70.47%            1
           11.81%     1.06%           63
            7.59%     0.71%           60
            4.33%    12.20%            2
            3.41%     0.33%           59
            2.05%     0.18%           64
            1.75%     1.09%            9
            1.64%     1.85%            5
            ...

   - Support Feodra mini-debuginfo which is a LZMA compressed symbol
     table inside ".gnu_debugdata" ELF section.

  perf annotate:

   - Add --code-with-type option to enable data-type profiling with the
     usual annotate output.

     Instead of focusing on data structure, it shows code annotation
     together with data type it accesses in case the instruction refers
     to a memory location (and it was able to resolve the target data
     type). Currently it only works with --stdio.

       $ perf annotate --stdio --code-with-type
       ...
        Percent |      Source code &amp; Disassembly of vmlinux for cpu/mem-loads,ldlat=30/pp (18 samples, percent: local period)
       ----------------------------------------------------------------------------------------------------------------------
                : 0                0xffffffff81050610 &lt;__fdget&gt;:
           0.00 :   ffffffff81050610:        callq   0xffffffff81c01b80 &lt;__fentry__&gt;           # data-type: (stack operation)
           0.00 :   ffffffff81050615:        pushq   %rbp              # data-type: (stack operation)
           0.00 :   ffffffff81050616:        movq    %rsp, %rbp
           0.00 :   ffffffff81050619:        pushq   %r15              # data-type: (stack operation)
           0.00 :   ffffffff8105061b:        pushq   %r14              # data-type: (stack operation)
           0.00 :   ffffffff8105061d:        pushq   %rbx              # data-type: (stack operation)
           0.00 :   ffffffff8105061e:        subq    $0x10, %rsp
           0.00 :   ffffffff81050622:        movl    %edi, %ebx
           0.00 :   ffffffff81050624:        movq    %gs:0x7efc4814(%rip), %rax  # 0x14e40 &lt;current_task&gt;              # data-type: struct task_struct* +0
           0.00 :   ffffffff8105062c:        movq    0x8d0(%rax), %r14         # data-type: struct task_struct +0x8d0 (files)
           0.00 :   ffffffff81050633:        movl    (%r14), %eax              # data-type: struct files_struct +0 (count.counter)
           0.00 :   ffffffff81050636:        cmpl    $0x1, %eax
           0.00 :   ffffffff81050639:        je      0xffffffff810506a9 &lt;__fdget+0x99&gt;
           0.00 :   ffffffff8105063b:        movq    0x20(%r14), %rcx          # data-type: struct files_struct +0x20 (fdt)
           0.00 :   ffffffff8105063f:        movl    (%rcx), %eax              # data-type: struct fdtable +0 (max_fds)
           0.00 :   ffffffff81050641:        cmpl    %ebx, %eax
           0.00 :   ffffffff81050643:        jbe     0xffffffff810506ef &lt;__fdget+0xdf&gt;
           0.00 :   ffffffff81050649:        movl    %ebx, %r15d
           5.56 :   ffffffff8105064c:        movq    0x8(%rcx), %rdx           # data-type: struct fdtable +0x8 (fd)
  	...

     The "# data-type:" part was added with this change. The first few
     entries are not very interesting. But later you can it accesses a
     couple of fields in the task_struct, files_struct and fdtable.

  perf trace:

   - Support syscall tracing for different ABI. For example it can trace
     system calls for 32-bit applications on 64-bit kernel
     transparently.

   - Add --summary-mode=total option to show global syscall summary. The
     default is 'thread' to show per-thread syscall summary.

  Python support:

   - Add more interfaces to 'perf' module to parse events, and config,
     enable or disable the event list properly so that it can implement
     basic functionalities purely in Python. There is an example code
     for these new interfaces in python/tracepoint.py.

   - Add mypy and pylint support to enable build time checking. Fix some
     code based on the findings from these tools.

  Internals:

   - Introduce io_dir__readdir() API to make directory traveral (usually
     for proc or sysfs) efficient with less memory footprint.

  JSON vendor events:

   - Add events and metrics for ARM Neoverse N3 and V3

   - Update events and metrics on various Intel CPUs

   - Add/update events for a number of SiFive processors"

* tag 'perf-tools-for-v6.15-2025-03-27' of git://git.kernel.org/pub/scm/linux/kernel/git/perf/perf-tools: (229 commits)
  perf bpf-filter: Fix a parsing error with comma
  perf report: Fix a memory leak for perf_env on AMD
  perf trace: Fix wrong size to bpf_map__update_elem call
  perf tools: annotate asm_pure_loop.S
  perf python: Fix setup.py mypy errors
  perf test: Address attr.py mypy error
  perf build: Add pylint build tests
  perf build: Add mypy build tests
  perf build: Rename TEST_LOGS to SHELL_TEST_LOGS
  tools/build: Don't pass test log files to linker
  perf bench sched pipe: fix enforced blocking reads in worker_thread
  perf tools: Fix is_compat_mode build break in ppc64
  perf build: filter all combinations of -flto for libperl
  perf vendor events arm64 AmpereOneX: Fix frontend_bound calculation
  perf vendor events arm64: AmpereOne/AmpereOneX: Mark LD_RETIRED impacted by errata
  perf trace: Fix evlist memory leak
  perf trace: Fix BTF memory leak
  perf trace: Make syscall table stable
  perf syscalltbl: Mask off ABI type for MIPS system calls
  perf build: Remove Makefile.syscalls
  ...
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
Pull perf tools updates from Namhyung Kim:
 "perf record:

   - Introduce latency profiling using scheduler information.

     The latency profiling is to show impacts on wall-time rather than
     cpu-time. By tracking context switches, it can weight samples and
     find which part of the code contributed more to the execution
     latency.

     The value (period) of the sample is weighted by dividing it by the
     number of parallel execution at the moment. The parallelism is
     tracked in perf report with sched-switch records. This will reduce
     the portion that are run in parallel and in turn increase the
     portion of serial executions.

     For now, it's limited to profile processes, IOW system-wide
     profiling is not supported. You can add --latency option to enable
     this.

       $ perf record --latency -- make -C tools/perf

     I've run the above command for perf build which adds -j option to
     make with the number of CPUs in the system internally. Normally
     it'd show something like below:

       $ perf report -F overhead,comm
       ...
       #
       # Overhead  Command
       # ........  ...............
       #
           78.97%  cc1
            6.54%  python3
            4.21%  shellcheck
            3.28%  ld
            1.80%  as
            1.37%  cc1plus
            0.80%  sh
            0.62%  clang
            0.56%  gcc
            0.44%  perl
            0.39%  make
  	 ...

     The cc1 takes around 80% of the overhead as it's the actual
     compiler. However it runs in parallel so its contribution to
     latency may be less than that. Now, perf report will show both
     overhead and latency (if --latency was given at record time) like
     below:

       $ perf report -s comm
       ...
       #
       # Overhead   Latency  Command
       # ........  ........  ...............
       #
           78.97%    48.66%  cc1
            6.54%    25.68%  python3
            4.21%     0.39%  shellcheck
            3.28%    13.70%  ld
            1.80%     2.56%  as
            1.37%     3.08%  cc1plus
            0.80%     0.98%  sh
            0.62%     0.61%  clang
            0.56%     0.33%  gcc
            0.44%     1.71%  perl
            0.39%     0.83%  make
  	 ...

     You can see latency of cc1 goes down to around 50% and python3 and
     ld contribute a lot more than their overhead. You can use --latency
     option in perf report to get the same result but ordered by
     latency.

       $ perf report --latency -s comm

  perf report:

   - As a side effect of the latency profiling work, it adds a new
     output field 'latency' and a sort key 'parallelism'. The below is a
     result from my system with 64 CPUs. The build was well-parallelized
     but contained some serial portions.

       $ perf report -s parallelism
       ...
       #
       # Overhead   Latency  Parallelism
       # ........  ........  ...........
       #
           16.95%     1.54%           62
           13.38%     1.24%           61
           12.50%    70.47%            1
           11.81%     1.06%           63
            7.59%     0.71%           60
            4.33%    12.20%            2
            3.41%     0.33%           59
            2.05%     0.18%           64
            1.75%     1.09%            9
            1.64%     1.85%            5
            ...

   - Support Feodra mini-debuginfo which is a LZMA compressed symbol
     table inside ".gnu_debugdata" ELF section.

  perf annotate:

   - Add --code-with-type option to enable data-type profiling with the
     usual annotate output.

     Instead of focusing on data structure, it shows code annotation
     together with data type it accesses in case the instruction refers
     to a memory location (and it was able to resolve the target data
     type). Currently it only works with --stdio.

       $ perf annotate --stdio --code-with-type
       ...
        Percent |      Source code &amp; Disassembly of vmlinux for cpu/mem-loads,ldlat=30/pp (18 samples, percent: local period)
       ----------------------------------------------------------------------------------------------------------------------
                : 0                0xffffffff81050610 &lt;__fdget&gt;:
           0.00 :   ffffffff81050610:        callq   0xffffffff81c01b80 &lt;__fentry__&gt;           # data-type: (stack operation)
           0.00 :   ffffffff81050615:        pushq   %rbp              # data-type: (stack operation)
           0.00 :   ffffffff81050616:        movq    %rsp, %rbp
           0.00 :   ffffffff81050619:        pushq   %r15              # data-type: (stack operation)
           0.00 :   ffffffff8105061b:        pushq   %r14              # data-type: (stack operation)
           0.00 :   ffffffff8105061d:        pushq   %rbx              # data-type: (stack operation)
           0.00 :   ffffffff8105061e:        subq    $0x10, %rsp
           0.00 :   ffffffff81050622:        movl    %edi, %ebx
           0.00 :   ffffffff81050624:        movq    %gs:0x7efc4814(%rip), %rax  # 0x14e40 &lt;current_task&gt;              # data-type: struct task_struct* +0
           0.00 :   ffffffff8105062c:        movq    0x8d0(%rax), %r14         # data-type: struct task_struct +0x8d0 (files)
           0.00 :   ffffffff81050633:        movl    (%r14), %eax              # data-type: struct files_struct +0 (count.counter)
           0.00 :   ffffffff81050636:        cmpl    $0x1, %eax
           0.00 :   ffffffff81050639:        je      0xffffffff810506a9 &lt;__fdget+0x99&gt;
           0.00 :   ffffffff8105063b:        movq    0x20(%r14), %rcx          # data-type: struct files_struct +0x20 (fdt)
           0.00 :   ffffffff8105063f:        movl    (%rcx), %eax              # data-type: struct fdtable +0 (max_fds)
           0.00 :   ffffffff81050641:        cmpl    %ebx, %eax
           0.00 :   ffffffff81050643:        jbe     0xffffffff810506ef &lt;__fdget+0xdf&gt;
           0.00 :   ffffffff81050649:        movl    %ebx, %r15d
           5.56 :   ffffffff8105064c:        movq    0x8(%rcx), %rdx           # data-type: struct fdtable +0x8 (fd)
  	...

     The "# data-type:" part was added with this change. The first few
     entries are not very interesting. But later you can it accesses a
     couple of fields in the task_struct, files_struct and fdtable.

  perf trace:

   - Support syscall tracing for different ABI. For example it can trace
     system calls for 32-bit applications on 64-bit kernel
     transparently.

   - Add --summary-mode=total option to show global syscall summary. The
     default is 'thread' to show per-thread syscall summary.

  Python support:

   - Add more interfaces to 'perf' module to parse events, and config,
     enable or disable the event list properly so that it can implement
     basic functionalities purely in Python. There is an example code
     for these new interfaces in python/tracepoint.py.

   - Add mypy and pylint support to enable build time checking. Fix some
     code based on the findings from these tools.

  Internals:

   - Introduce io_dir__readdir() API to make directory traveral (usually
     for proc or sysfs) efficient with less memory footprint.

  JSON vendor events:

   - Add events and metrics for ARM Neoverse N3 and V3

   - Update events and metrics on various Intel CPUs

   - Add/update events for a number of SiFive processors"

* tag 'perf-tools-for-v6.15-2025-03-27' of git://git.kernel.org/pub/scm/linux/kernel/git/perf/perf-tools: (229 commits)
  perf bpf-filter: Fix a parsing error with comma
  perf report: Fix a memory leak for perf_env on AMD
  perf trace: Fix wrong size to bpf_map__update_elem call
  perf tools: annotate asm_pure_loop.S
  perf python: Fix setup.py mypy errors
  perf test: Address attr.py mypy error
  perf build: Add pylint build tests
  perf build: Add mypy build tests
  perf build: Rename TEST_LOGS to SHELL_TEST_LOGS
  tools/build: Don't pass test log files to linker
  perf bench sched pipe: fix enforced blocking reads in worker_thread
  perf tools: Fix is_compat_mode build break in ppc64
  perf build: filter all combinations of -flto for libperl
  perf vendor events arm64 AmpereOneX: Fix frontend_bound calculation
  perf vendor events arm64: AmpereOne/AmpereOneX: Mark LD_RETIRED impacted by errata
  perf trace: Fix evlist memory leak
  perf trace: Fix BTF memory leak
  perf trace: Make syscall table stable
  perf syscalltbl: Mask off ABI type for MIPS system calls
  perf build: Remove Makefile.syscalls
  ...
</pre>
</div>
</content>
</entry>
<entry>
<title>Merge tag 'for-linus' of git://git.kernel.org/pub/scm/virt/kvm/kvm</title>
<updated>2025-03-25T21:22:07+00:00</updated>
<author>
<name>Linus Torvalds</name>
<email>torvalds@linux-foundation.org</email>
</author>
<published>2025-03-25T21:22:07+00:00</published>
<link rel='alternate' type='text/html' href='https://git.toradex.cn/cgit/linux-toradex.git/commit/?id=edb0e8f6e2e19c10a240d08c5d6f3ab3cdd38808'/>
<id>edb0e8f6e2e19c10a240d08c5d6f3ab3cdd38808</id>
<content type='text'>
Pull kvm updates from Paolo Bonzini:
 "ARM:

   - Nested virtualization support for VGICv3, giving the nested
     hypervisor control of the VGIC hardware when running an L2 VM

   - Removal of 'late' nested virtualization feature register masking,
     making the supported feature set directly visible to userspace

   - Support for emulating FEAT_PMUv3 on Apple silicon, taking advantage
     of an IMPLEMENTATION DEFINED trap that covers all PMUv3 registers

   - Paravirtual interface for discovering the set of CPU
     implementations where a VM may run, addressing a longstanding issue
     of guest CPU errata awareness in big-little systems and
     cross-implementation VM migration

   - Userspace control of the registers responsible for identifying a
     particular CPU implementation (MIDR_EL1, REVIDR_EL1, AIDR_EL1),
     allowing VMs to be migrated cross-implementation

   - pKVM updates, including support for tracking stage-2 page table
     allocations in the protected hypervisor in the 'SecPageTable' stat

   - Fixes to vPMU, ensuring that userspace updates to the vPMU after
     KVM_RUN are reflected into the backing perf events

  LoongArch:

   - Remove unnecessary header include path

   - Assume constant PGD during VM context switch

   - Add perf events support for guest VM

  RISC-V:

   - Disable the kernel perf counter during configure

   - KVM selftests improvements for PMU

   - Fix warning at the time of KVM module removal

  x86:

   - Add support for aging of SPTEs without holding mmu_lock.

     Not taking mmu_lock allows multiple aging actions to run in
     parallel, and more importantly avoids stalling vCPUs. This includes
     an implementation of per-rmap-entry locking; aging the gfn is done
     with only a per-rmap single-bin spinlock taken, whereas locking an
     rmap for write requires taking both the per-rmap spinlock and the
     mmu_lock.

     Note that this decreases slightly the accuracy of accessed-page
     information, because changes to the SPTE outside aging might not
     use atomic operations even if they could race against a clear of
     the Accessed bit.

     This is deliberate because KVM and mm/ tolerate false
     positives/negatives for accessed information, and testing has shown
     that reducing the latency of aging is far more beneficial to
     overall system performance than providing "perfect" young/old
     information.

   - Defer runtime CPUID updates until KVM emulates a CPUID instruction,
     to coalesce updates when multiple pieces of vCPU state are
     changing, e.g. as part of a nested transition

   - Fix a variety of nested emulation bugs, and add VMX support for
     synthesizing nested VM-Exit on interception (instead of injecting
     #UD into L2)

   - Drop "support" for async page faults for protected guests that do
     not set SEND_ALWAYS (i.e. that only want async page faults at CPL3)

   - Bring a bit of sanity to x86's VM teardown code, which has
     accumulated a lot of cruft over the years. Particularly, destroy
     vCPUs before the MMU, despite the latter being a VM-wide operation

   - Add common secure TSC infrastructure for use within SNP and in the
     future TDX

   - Block KVM_CAP_SYNC_REGS if guest state is protected. It does not
     make sense to use the capability if the relevant registers are not
     available for reading or writing

   - Don't take kvm-&gt;lock when iterating over vCPUs in the suspend
     notifier to fix a largely theoretical deadlock

   - Use the vCPU's actual Xen PV clock information when starting the
     Xen timer, as the cached state in arch.hv_clock can be stale/bogus

   - Fix a bug where KVM could bleed PVCLOCK_GUEST_STOPPED across
     different PV clocks; restrict PVCLOCK_GUEST_STOPPED to kvmclock, as
     KVM's suspend notifier only accounts for kvmclock, and there's no
     evidence that the flag is actually supported by Xen guests

   - Clean up the per-vCPU "cache" of its reference pvclock, and instead
     only track the vCPU's TSC scaling (multipler+shift) metadata (which
     is moderately expensive to compute, and rarely changes for modern
     setups)

   - Don't write to the Xen hypercall page on MSR writes that are
     initiated by the host (userspace or KVM) to fix a class of bugs
     where KVM can write to guest memory at unexpected times, e.g.
     during vCPU creation if userspace has set the Xen hypercall MSR
     index to collide with an MSR that KVM emulates

   - Restrict the Xen hypercall MSR index to the unofficial synthetic
     range to reduce the set of possible collisions with MSRs that are
     emulated by KVM (collisions can still happen as KVM emulates
     Hyper-V MSRs, which also reside in the synthetic range)

   - Clean up and optimize KVM's handling of Xen MSR writes and
     xen_hvm_config

   - Update Xen TSC leaves during CPUID emulation instead of modifying
     the CPUID entries when updating PV clocks; there is no guarantee PV
     clocks will be updated between TSC frequency changes and CPUID
     emulation, and guest reads of the TSC leaves should be rare, i.e.
     are not a hot path

  x86 (Intel):

   - Fix a bug where KVM unnecessarily reads XFD_ERR from hardware and
     thus modifies the vCPU's XFD_ERR on a #NM due to CR0.TS=1

   - Pass XFD_ERR as the payload when injecting #NM, as a preparatory
     step for upcoming FRED virtualization support

   - Decouple the EPT entry RWX protection bit macros from the EPT
     Violation bits, both as a general cleanup and in anticipation of
     adding support for emulating Mode-Based Execution Control (MBEC)

   - Reject KVM_RUN if userspace manages to gain control and stuff
     invalid guest state while KVM is in the middle of emulating nested
     VM-Enter

   - Add a macro to handle KVM's sanity checks on entry/exit VMCS
     control pairs in anticipation of adding sanity checks for secondary
     exit controls (the primary field is out of bits)

  x86 (AMD):

   - Ensure the PSP driver is initialized when both the PSP and KVM
     modules are built-in (the initcall framework doesn't handle
     dependencies)

   - Use long-term pins when registering encrypted memory regions, so
     that the pages are migrated out of MIGRATE_CMA/ZONE_MOVABLE and
     don't lead to excessive fragmentation

   - Add macros and helpers for setting GHCB return/error codes

   - Add support for Idle HLT interception, which elides interception if
     the vCPU has a pending, unmasked virtual IRQ when HLT is executed

   - Fix a bug in INVPCID emulation where KVM fails to check for a
     non-canonical address

   - Don't attempt VMRUN for SEV-ES+ guests if the vCPU's VMSA is
     invalid, e.g. because the vCPU was "destroyed" via SNP's AP
     Creation hypercall

   - Reject SNP AP Creation if the requested SEV features for the vCPU
     don't match the VM's configured set of features

  Selftests:

   - Fix again the Intel PMU counters test; add a data load and do
     CLFLUSH{OPT} on the data instead of executing code. The theory is
     that modern Intel CPUs have learned new code prefetching tricks
     that bypass the PMU counters

   - Fix a flaw in the Intel PMU counters test where it asserts that an
     event is counting correctly without actually knowing what the event
     counts on the underlying hardware

   - Fix a variety of flaws, bugs, and false failures/passes
     dirty_log_test, and improve its coverage by collecting all dirty
     entries on each iteration

   - Fix a few minor bugs related to handling of stats FDs

   - Add infrastructure to make vCPU and VM stats FDs available to tests
     by default (open the FDs during VM/vCPU creation)

   - Relax an assertion on the number of HLT exits in the xAPIC IPI test
     when running on a CPU that supports AMD's Idle HLT (which elides
     interception of HLT if a virtual IRQ is pending and unmasked)"

* tag 'for-linus' of git://git.kernel.org/pub/scm/virt/kvm/kvm: (216 commits)
  RISC-V: KVM: Optimize comments in kvm_riscv_vcpu_isa_disable_allowed
  RISC-V: KVM: Teardown riscv specific bits after kvm_exit
  LoongArch: KVM: Register perf callbacks for guest
  LoongArch: KVM: Implement arch-specific functions for guest perf
  LoongArch: KVM: Add stub for kvm_arch_vcpu_preempted_in_kernel()
  LoongArch: KVM: Remove PGD saving during VM context switch
  LoongArch: KVM: Remove unnecessary header include path
  KVM: arm64: Tear down vGIC on failed vCPU creation
  KVM: arm64: PMU: Reload when resetting
  KVM: arm64: PMU: Reload when user modifies registers
  KVM: arm64: PMU: Fix SET_ONE_REG for vPMC regs
  KVM: arm64: PMU: Assume PMU presence in pmu-emul.c
  KVM: arm64: PMU: Set raw values from user to PM{C,I}NTEN{SET,CLR}, PMOVS{SET,CLR}
  KVM: arm64: Create each pKVM hyp vcpu after its corresponding host vcpu
  KVM: arm64: Factor out pKVM hyp vcpu creation to separate function
  KVM: arm64: Initialize HCRX_EL2 traps in pKVM
  KVM: arm64: Factor out setting HCRX_EL2 traps into separate function
  KVM: x86: block KVM_CAP_SYNC_REGS if guest state is protected
  KVM: x86: Add infrastructure for secure TSC
  KVM: x86: Push down setting vcpu.arch.user_set_tsc
  ...
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
Pull kvm updates from Paolo Bonzini:
 "ARM:

   - Nested virtualization support for VGICv3, giving the nested
     hypervisor control of the VGIC hardware when running an L2 VM

   - Removal of 'late' nested virtualization feature register masking,
     making the supported feature set directly visible to userspace

   - Support for emulating FEAT_PMUv3 on Apple silicon, taking advantage
     of an IMPLEMENTATION DEFINED trap that covers all PMUv3 registers

   - Paravirtual interface for discovering the set of CPU
     implementations where a VM may run, addressing a longstanding issue
     of guest CPU errata awareness in big-little systems and
     cross-implementation VM migration

   - Userspace control of the registers responsible for identifying a
     particular CPU implementation (MIDR_EL1, REVIDR_EL1, AIDR_EL1),
     allowing VMs to be migrated cross-implementation

   - pKVM updates, including support for tracking stage-2 page table
     allocations in the protected hypervisor in the 'SecPageTable' stat

   - Fixes to vPMU, ensuring that userspace updates to the vPMU after
     KVM_RUN are reflected into the backing perf events

  LoongArch:

   - Remove unnecessary header include path

   - Assume constant PGD during VM context switch

   - Add perf events support for guest VM

  RISC-V:

   - Disable the kernel perf counter during configure

   - KVM selftests improvements for PMU

   - Fix warning at the time of KVM module removal

  x86:

   - Add support for aging of SPTEs without holding mmu_lock.

     Not taking mmu_lock allows multiple aging actions to run in
     parallel, and more importantly avoids stalling vCPUs. This includes
     an implementation of per-rmap-entry locking; aging the gfn is done
     with only a per-rmap single-bin spinlock taken, whereas locking an
     rmap for write requires taking both the per-rmap spinlock and the
     mmu_lock.

     Note that this decreases slightly the accuracy of accessed-page
     information, because changes to the SPTE outside aging might not
     use atomic operations even if they could race against a clear of
     the Accessed bit.

     This is deliberate because KVM and mm/ tolerate false
     positives/negatives for accessed information, and testing has shown
     that reducing the latency of aging is far more beneficial to
     overall system performance than providing "perfect" young/old
     information.

   - Defer runtime CPUID updates until KVM emulates a CPUID instruction,
     to coalesce updates when multiple pieces of vCPU state are
     changing, e.g. as part of a nested transition

   - Fix a variety of nested emulation bugs, and add VMX support for
     synthesizing nested VM-Exit on interception (instead of injecting
     #UD into L2)

   - Drop "support" for async page faults for protected guests that do
     not set SEND_ALWAYS (i.e. that only want async page faults at CPL3)

   - Bring a bit of sanity to x86's VM teardown code, which has
     accumulated a lot of cruft over the years. Particularly, destroy
     vCPUs before the MMU, despite the latter being a VM-wide operation

   - Add common secure TSC infrastructure for use within SNP and in the
     future TDX

   - Block KVM_CAP_SYNC_REGS if guest state is protected. It does not
     make sense to use the capability if the relevant registers are not
     available for reading or writing

   - Don't take kvm-&gt;lock when iterating over vCPUs in the suspend
     notifier to fix a largely theoretical deadlock

   - Use the vCPU's actual Xen PV clock information when starting the
     Xen timer, as the cached state in arch.hv_clock can be stale/bogus

   - Fix a bug where KVM could bleed PVCLOCK_GUEST_STOPPED across
     different PV clocks; restrict PVCLOCK_GUEST_STOPPED to kvmclock, as
     KVM's suspend notifier only accounts for kvmclock, and there's no
     evidence that the flag is actually supported by Xen guests

   - Clean up the per-vCPU "cache" of its reference pvclock, and instead
     only track the vCPU's TSC scaling (multipler+shift) metadata (which
     is moderately expensive to compute, and rarely changes for modern
     setups)

   - Don't write to the Xen hypercall page on MSR writes that are
     initiated by the host (userspace or KVM) to fix a class of bugs
     where KVM can write to guest memory at unexpected times, e.g.
     during vCPU creation if userspace has set the Xen hypercall MSR
     index to collide with an MSR that KVM emulates

   - Restrict the Xen hypercall MSR index to the unofficial synthetic
     range to reduce the set of possible collisions with MSRs that are
     emulated by KVM (collisions can still happen as KVM emulates
     Hyper-V MSRs, which also reside in the synthetic range)

   - Clean up and optimize KVM's handling of Xen MSR writes and
     xen_hvm_config

   - Update Xen TSC leaves during CPUID emulation instead of modifying
     the CPUID entries when updating PV clocks; there is no guarantee PV
     clocks will be updated between TSC frequency changes and CPUID
     emulation, and guest reads of the TSC leaves should be rare, i.e.
     are not a hot path

  x86 (Intel):

   - Fix a bug where KVM unnecessarily reads XFD_ERR from hardware and
     thus modifies the vCPU's XFD_ERR on a #NM due to CR0.TS=1

   - Pass XFD_ERR as the payload when injecting #NM, as a preparatory
     step for upcoming FRED virtualization support

   - Decouple the EPT entry RWX protection bit macros from the EPT
     Violation bits, both as a general cleanup and in anticipation of
     adding support for emulating Mode-Based Execution Control (MBEC)

   - Reject KVM_RUN if userspace manages to gain control and stuff
     invalid guest state while KVM is in the middle of emulating nested
     VM-Enter

   - Add a macro to handle KVM's sanity checks on entry/exit VMCS
     control pairs in anticipation of adding sanity checks for secondary
     exit controls (the primary field is out of bits)

  x86 (AMD):

   - Ensure the PSP driver is initialized when both the PSP and KVM
     modules are built-in (the initcall framework doesn't handle
     dependencies)

   - Use long-term pins when registering encrypted memory regions, so
     that the pages are migrated out of MIGRATE_CMA/ZONE_MOVABLE and
     don't lead to excessive fragmentation

   - Add macros and helpers for setting GHCB return/error codes

   - Add support for Idle HLT interception, which elides interception if
     the vCPU has a pending, unmasked virtual IRQ when HLT is executed

   - Fix a bug in INVPCID emulation where KVM fails to check for a
     non-canonical address

   - Don't attempt VMRUN for SEV-ES+ guests if the vCPU's VMSA is
     invalid, e.g. because the vCPU was "destroyed" via SNP's AP
     Creation hypercall

   - Reject SNP AP Creation if the requested SEV features for the vCPU
     don't match the VM's configured set of features

  Selftests:

   - Fix again the Intel PMU counters test; add a data load and do
     CLFLUSH{OPT} on the data instead of executing code. The theory is
     that modern Intel CPUs have learned new code prefetching tricks
     that bypass the PMU counters

   - Fix a flaw in the Intel PMU counters test where it asserts that an
     event is counting correctly without actually knowing what the event
     counts on the underlying hardware

   - Fix a variety of flaws, bugs, and false failures/passes
     dirty_log_test, and improve its coverage by collecting all dirty
     entries on each iteration

   - Fix a few minor bugs related to handling of stats FDs

   - Add infrastructure to make vCPU and VM stats FDs available to tests
     by default (open the FDs during VM/vCPU creation)

   - Relax an assertion on the number of HLT exits in the xAPIC IPI test
     when running on a CPU that supports AMD's Idle HLT (which elides
     interception of HLT if a virtual IRQ is pending and unmasked)"

* tag 'for-linus' of git://git.kernel.org/pub/scm/virt/kvm/kvm: (216 commits)
  RISC-V: KVM: Optimize comments in kvm_riscv_vcpu_isa_disable_allowed
  RISC-V: KVM: Teardown riscv specific bits after kvm_exit
  LoongArch: KVM: Register perf callbacks for guest
  LoongArch: KVM: Implement arch-specific functions for guest perf
  LoongArch: KVM: Add stub for kvm_arch_vcpu_preempted_in_kernel()
  LoongArch: KVM: Remove PGD saving during VM context switch
  LoongArch: KVM: Remove unnecessary header include path
  KVM: arm64: Tear down vGIC on failed vCPU creation
  KVM: arm64: PMU: Reload when resetting
  KVM: arm64: PMU: Reload when user modifies registers
  KVM: arm64: PMU: Fix SET_ONE_REG for vPMC regs
  KVM: arm64: PMU: Assume PMU presence in pmu-emul.c
  KVM: arm64: PMU: Set raw values from user to PM{C,I}NTEN{SET,CLR}, PMOVS{SET,CLR}
  KVM: arm64: Create each pKVM hyp vcpu after its corresponding host vcpu
  KVM: arm64: Factor out pKVM hyp vcpu creation to separate function
  KVM: arm64: Initialize HCRX_EL2 traps in pKVM
  KVM: arm64: Factor out setting HCRX_EL2 traps into separate function
  KVM: x86: block KVM_CAP_SYNC_REGS if guest state is protected
  KVM: x86: Add infrastructure for secure TSC
  KVM: x86: Push down setting vcpu.arch.user_set_tsc
  ...
</pre>
</div>
</content>
</entry>
<entry>
<title>Merge tag 'x86_bugs_for_v6.15' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip</title>
<updated>2025-03-25T20:30:18+00:00</updated>
<author>
<name>Linus Torvalds</name>
<email>torvalds@linux-foundation.org</email>
</author>
<published>2025-03-25T20:30:18+00:00</published>
<link rel='alternate' type='text/html' href='https://git.toradex.cn/cgit/linux-toradex.git/commit/?id=906174776c0eb539e4d65c54a8019d954a6fb35d'/>
<id>906174776c0eb539e4d65c54a8019d954a6fb35d</id>
<content type='text'>
Pull x86 speculation mitigation updates from Borislav Petkov:

 - Some preparatory work to convert the mitigations machinery to
   mitigating attack vectors instead of single vulnerabilities

 - Untangle and remove a now unneeded X86_FEATURE_USE_IBPB flag

 - Add support for a Zen5-specific SRSO mitigation

 - Cleanups and minor improvements

* tag 'x86_bugs_for_v6.15' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  x86/bugs: Make spectre user default depend on MITIGATION_SPECTRE_V2
  x86/bugs: Use the cpu_smt_possible() helper instead of open-coded code
  x86/bugs: Add AUTO mitigations for mds/taa/mmio/rfds
  x86/bugs: Relocate mds/taa/mmio/rfds defines
  x86/bugs: Add X86_BUG_SPECTRE_V2_USER
  x86/bugs: Remove X86_FEATURE_USE_IBPB
  KVM: nVMX: Always use IBPB to properly virtualize IBRS
  x86/bugs: Use a static branch to guard IBPB on vCPU switch
  x86/bugs: Remove the X86_FEATURE_USE_IBPB check in ib_prctl_set()
  x86/mm: Remove X86_FEATURE_USE_IBPB checks in cond_mitigation()
  x86/bugs: Move the X86_FEATURE_USE_IBPB check into callers
  x86/bugs: KVM: Add support for SRSO_MSR_FIX
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
Pull x86 speculation mitigation updates from Borislav Petkov:

 - Some preparatory work to convert the mitigations machinery to
   mitigating attack vectors instead of single vulnerabilities

 - Untangle and remove a now unneeded X86_FEATURE_USE_IBPB flag

 - Add support for a Zen5-specific SRSO mitigation

 - Cleanups and minor improvements

* tag 'x86_bugs_for_v6.15' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  x86/bugs: Make spectre user default depend on MITIGATION_SPECTRE_V2
  x86/bugs: Use the cpu_smt_possible() helper instead of open-coded code
  x86/bugs: Add AUTO mitigations for mds/taa/mmio/rfds
  x86/bugs: Relocate mds/taa/mmio/rfds defines
  x86/bugs: Add X86_BUG_SPECTRE_V2_USER
  x86/bugs: Remove X86_FEATURE_USE_IBPB
  KVM: nVMX: Always use IBPB to properly virtualize IBRS
  x86/bugs: Use a static branch to guard IBPB on vCPU switch
  x86/bugs: Remove the X86_FEATURE_USE_IBPB check in ib_prctl_set()
  x86/mm: Remove X86_FEATURE_USE_IBPB checks in cond_mitigation()
  x86/bugs: Move the X86_FEATURE_USE_IBPB check into callers
  x86/bugs: KVM: Add support for SRSO_MSR_FIX
</pre>
</div>
</content>
</entry>
<entry>
<title>Merge tag 'x86-core-2025-03-22' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip</title>
<updated>2025-03-25T05:06:11+00:00</updated>
<author>
<name>Linus Torvalds</name>
<email>torvalds@linux-foundation.org</email>
</author>
<published>2025-03-25T05:06:11+00:00</published>
<link rel='alternate' type='text/html' href='https://git.toradex.cn/cgit/linux-toradex.git/commit/?id=e34c38057a131d14e47b4acb461564d9f351b9f7'/>
<id>e34c38057a131d14e47b4acb461564d9f351b9f7</id>
<content type='text'>
Pull core x86 updates from Ingo Molnar:
 "x86 CPU features support:
   - Generate the &lt;asm/cpufeaturemasks.h&gt; header based on build config
     (H. Peter Anvin, Xin Li)
   - x86 CPUID parsing updates and fixes (Ahmed S. Darwish)
   - Introduce the 'setcpuid=' boot parameter (Brendan Jackman)
   - Enable modifying CPU bug flags with '{clear,set}puid=' (Brendan
     Jackman)
   - Utilize CPU-type for CPU matching (Pawan Gupta)
   - Warn about unmet CPU feature dependencies (Sohil Mehta)
   - Prepare for new Intel Family numbers (Sohil Mehta)

  Percpu code:
   - Standardize &amp; reorganize the x86 percpu layout and related cleanups
     (Brian Gerst)
   - Convert the stackprotector canary to a regular percpu variable
     (Brian Gerst)
   - Add a percpu subsection for cache hot data (Brian Gerst)
   - Unify __pcpu_op{1,2}_N() macros to __pcpu_op_N() (Uros Bizjak)
   - Construct __percpu_seg_override from __percpu_seg (Uros Bizjak)

  MM:
   - Add support for broadcast TLB invalidation using AMD's INVLPGB
     instruction (Rik van Riel)
   - Rework ROX cache to avoid writable copy (Mike Rapoport)
   - PAT: restore large ROX pages after fragmentation (Kirill A.
     Shutemov, Mike Rapoport)
   - Make memremap(MEMREMAP_WB) map memory as encrypted by default
     (Kirill A. Shutemov)
   - Robustify page table initialization (Kirill A. Shutemov)
   - Fix flush_tlb_range() when used for zapping normal PMDs (Jann Horn)
   - Clear _PAGE_DIRTY for kernel mappings when we clear _PAGE_RW
     (Matthew Wilcox)

  KASLR:
   - x86/kaslr: Reduce KASLR entropy on most x86 systems, to support PCI
     BAR space beyond the 10TiB region (CONFIG_PCI_P2PDMA=y) (Balbir
     Singh)

  CPU bugs:
   - Implement FineIBT-BHI mitigation (Peter Zijlstra)
   - speculation: Simplify and make CALL_NOSPEC consistent (Pawan Gupta)
   - speculation: Add a conditional CS prefix to CALL_NOSPEC (Pawan
     Gupta)
   - RFDS: Exclude P-only parts from the RFDS affected list (Pawan
     Gupta)

  System calls:
   - Break up entry/common.c (Brian Gerst)
   - Move sysctls into arch/x86 (Joel Granados)

  Intel LAM support updates: (Maciej Wieczor-Retman)
   - selftests/lam: Move cpu_has_la57() to use cpuinfo flag
   - selftests/lam: Skip test if LAM is disabled
   - selftests/lam: Test get_user() LAM pointer handling

  AMD SMN access updates:
   - Add SMN offsets to exclusive region access (Mario Limonciello)
   - Add support for debugfs access to SMN registers (Mario Limonciello)
   - Have HSMP use SMN through AMD_NODE (Yazen Ghannam)

  Power management updates: (Patryk Wlazlyn)
   - Allow calling mwait_play_dead with an arbitrary hint
   - ACPI/processor_idle: Add FFH state handling
   - intel_idle: Provide the default enter_dead() handler
   - Eliminate mwait_play_dead_cpuid_hint()

  Build system:
   - Raise the minimum GCC version to 8.1 (Brian Gerst)
   - Raise the minimum LLVM version to 15.0.0 (Nathan Chancellor)

  Kconfig: (Arnd Bergmann)
   - Add cmpxchg8b support back to Geode CPUs
   - Drop 32-bit "bigsmp" machine support
   - Rework CONFIG_GENERIC_CPU compiler flags
   - Drop configuration options for early 64-bit CPUs
   - Remove CONFIG_HIGHMEM64G support
   - Drop CONFIG_SWIOTLB for PAE
   - Drop support for CONFIG_HIGHPTE
   - Document CONFIG_X86_INTEL_MID as 64-bit-only
   - Remove old STA2x11 support
   - Only allow CONFIG_EISA for 32-bit

  Headers:
   - Replace __ASSEMBLY__ with __ASSEMBLER__ in UAPI and non-UAPI
     headers (Thomas Huth)

  Assembly code &amp; machine code patching:
   - x86/alternatives: Simplify alternative_call() interface (Josh
     Poimboeuf)
   - x86/alternatives: Simplify callthunk patching (Peter Zijlstra)
   - KVM: VMX: Use named operands in inline asm (Josh Poimboeuf)
   - x86/hyperv: Use named operands in inline asm (Josh Poimboeuf)
   - x86/traps: Cleanup and robustify decode_bug() (Peter Zijlstra)
   - x86/kexec: Merge x86_32 and x86_64 code using macros from
     &lt;asm/asm.h&gt; (Uros Bizjak)
   - Use named operands in inline asm (Uros Bizjak)
   - Improve performance by using asm_inline() for atomic locking
     instructions (Uros Bizjak)

  Earlyprintk:
   - Harden early_serial (Peter Zijlstra)

  NMI handler:
   - Add an emergency handler in nmi_desc &amp; use it in
     nmi_shootdown_cpus() (Waiman Long)

  Miscellaneous fixes and cleanups:
   - by Ahmed S. Darwish, Andy Shevchenko, Ard Biesheuvel, Artem
     Bityutskiy, Borislav Petkov, Brendan Jackman, Brian Gerst, Dan
     Carpenter, Dr. David Alan Gilbert, H. Peter Anvin, Ingo Molnar,
     Josh Poimboeuf, Kevin Brodsky, Mike Rapoport, Lukas Bulwahn, Maciej
     Wieczor-Retman, Max Grobecker, Patryk Wlazlyn, Pawan Gupta, Peter
     Zijlstra, Philip Redkin, Qasim Ijaz, Rik van Riel, Thomas Gleixner,
     Thorsten Blum, Tom Lendacky, Tony Luck, Uros Bizjak, Vitaly
     Kuznetsov, Xin Li, liuye"

* tag 'x86-core-2025-03-22' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (211 commits)
  zstd: Increase DYNAMIC_BMI2 GCC version cutoff from 4.8 to 11.0 to work around compiler segfault
  x86/asm: Make asm export of __ref_stack_chk_guard unconditional
  x86/mm: Only do broadcast flush from reclaim if pages were unmapped
  perf/x86/intel, x86/cpu: Replace Pentium 4 model checks with VFM ones
  perf/x86/intel, x86/cpu: Simplify Intel PMU initialization
  x86/headers: Replace __ASSEMBLY__ with __ASSEMBLER__ in non-UAPI headers
  x86/headers: Replace __ASSEMBLY__ with __ASSEMBLER__ in UAPI headers
  x86/locking/atomic: Improve performance by using asm_inline() for atomic locking instructions
  x86/asm: Use asm_inline() instead of asm() in clwb()
  x86/asm: Use CLFLUSHOPT and CLWB mnemonics in &lt;asm/special_insns.h&gt;
  x86/hweight: Use asm_inline() instead of asm()
  x86/hweight: Use ASM_CALL_CONSTRAINT in inline asm()
  x86/hweight: Use named operands in inline asm()
  x86/stackprotector/64: Only export __ref_stack_chk_guard on CONFIG_SMP
  x86/head/64: Avoid Clang &lt; 17 stack protector in startup code
  x86/kexec: Merge x86_32 and x86_64 code using macros from &lt;asm/asm.h&gt;
  x86/runtime-const: Add the RUNTIME_CONST_PTR assembly macro
  x86/cpu/intel: Limit the non-architectural constant_tsc model checks
  x86/mm/pat: Replace Intel x86_model checks with VFM ones
  x86/cpu/intel: Fix fast string initialization for extended Families
  ...
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
Pull core x86 updates from Ingo Molnar:
 "x86 CPU features support:
   - Generate the &lt;asm/cpufeaturemasks.h&gt; header based on build config
     (H. Peter Anvin, Xin Li)
   - x86 CPUID parsing updates and fixes (Ahmed S. Darwish)
   - Introduce the 'setcpuid=' boot parameter (Brendan Jackman)
   - Enable modifying CPU bug flags with '{clear,set}puid=' (Brendan
     Jackman)
   - Utilize CPU-type for CPU matching (Pawan Gupta)
   - Warn about unmet CPU feature dependencies (Sohil Mehta)
   - Prepare for new Intel Family numbers (Sohil Mehta)

  Percpu code:
   - Standardize &amp; reorganize the x86 percpu layout and related cleanups
     (Brian Gerst)
   - Convert the stackprotector canary to a regular percpu variable
     (Brian Gerst)
   - Add a percpu subsection for cache hot data (Brian Gerst)
   - Unify __pcpu_op{1,2}_N() macros to __pcpu_op_N() (Uros Bizjak)
   - Construct __percpu_seg_override from __percpu_seg (Uros Bizjak)

  MM:
   - Add support for broadcast TLB invalidation using AMD's INVLPGB
     instruction (Rik van Riel)
   - Rework ROX cache to avoid writable copy (Mike Rapoport)
   - PAT: restore large ROX pages after fragmentation (Kirill A.
     Shutemov, Mike Rapoport)
   - Make memremap(MEMREMAP_WB) map memory as encrypted by default
     (Kirill A. Shutemov)
   - Robustify page table initialization (Kirill A. Shutemov)
   - Fix flush_tlb_range() when used for zapping normal PMDs (Jann Horn)
   - Clear _PAGE_DIRTY for kernel mappings when we clear _PAGE_RW
     (Matthew Wilcox)

  KASLR:
   - x86/kaslr: Reduce KASLR entropy on most x86 systems, to support PCI
     BAR space beyond the 10TiB region (CONFIG_PCI_P2PDMA=y) (Balbir
     Singh)

  CPU bugs:
   - Implement FineIBT-BHI mitigation (Peter Zijlstra)
   - speculation: Simplify and make CALL_NOSPEC consistent (Pawan Gupta)
   - speculation: Add a conditional CS prefix to CALL_NOSPEC (Pawan
     Gupta)
   - RFDS: Exclude P-only parts from the RFDS affected list (Pawan
     Gupta)

  System calls:
   - Break up entry/common.c (Brian Gerst)
   - Move sysctls into arch/x86 (Joel Granados)

  Intel LAM support updates: (Maciej Wieczor-Retman)
   - selftests/lam: Move cpu_has_la57() to use cpuinfo flag
   - selftests/lam: Skip test if LAM is disabled
   - selftests/lam: Test get_user() LAM pointer handling

  AMD SMN access updates:
   - Add SMN offsets to exclusive region access (Mario Limonciello)
   - Add support for debugfs access to SMN registers (Mario Limonciello)
   - Have HSMP use SMN through AMD_NODE (Yazen Ghannam)

  Power management updates: (Patryk Wlazlyn)
   - Allow calling mwait_play_dead with an arbitrary hint
   - ACPI/processor_idle: Add FFH state handling
   - intel_idle: Provide the default enter_dead() handler
   - Eliminate mwait_play_dead_cpuid_hint()

  Build system:
   - Raise the minimum GCC version to 8.1 (Brian Gerst)
   - Raise the minimum LLVM version to 15.0.0 (Nathan Chancellor)

  Kconfig: (Arnd Bergmann)
   - Add cmpxchg8b support back to Geode CPUs
   - Drop 32-bit "bigsmp" machine support
   - Rework CONFIG_GENERIC_CPU compiler flags
   - Drop configuration options for early 64-bit CPUs
   - Remove CONFIG_HIGHMEM64G support
   - Drop CONFIG_SWIOTLB for PAE
   - Drop support for CONFIG_HIGHPTE
   - Document CONFIG_X86_INTEL_MID as 64-bit-only
   - Remove old STA2x11 support
   - Only allow CONFIG_EISA for 32-bit

  Headers:
   - Replace __ASSEMBLY__ with __ASSEMBLER__ in UAPI and non-UAPI
     headers (Thomas Huth)

  Assembly code &amp; machine code patching:
   - x86/alternatives: Simplify alternative_call() interface (Josh
     Poimboeuf)
   - x86/alternatives: Simplify callthunk patching (Peter Zijlstra)
   - KVM: VMX: Use named operands in inline asm (Josh Poimboeuf)
   - x86/hyperv: Use named operands in inline asm (Josh Poimboeuf)
   - x86/traps: Cleanup and robustify decode_bug() (Peter Zijlstra)
   - x86/kexec: Merge x86_32 and x86_64 code using macros from
     &lt;asm/asm.h&gt; (Uros Bizjak)
   - Use named operands in inline asm (Uros Bizjak)
   - Improve performance by using asm_inline() for atomic locking
     instructions (Uros Bizjak)

  Earlyprintk:
   - Harden early_serial (Peter Zijlstra)

  NMI handler:
   - Add an emergency handler in nmi_desc &amp; use it in
     nmi_shootdown_cpus() (Waiman Long)

  Miscellaneous fixes and cleanups:
   - by Ahmed S. Darwish, Andy Shevchenko, Ard Biesheuvel, Artem
     Bityutskiy, Borislav Petkov, Brendan Jackman, Brian Gerst, Dan
     Carpenter, Dr. David Alan Gilbert, H. Peter Anvin, Ingo Molnar,
     Josh Poimboeuf, Kevin Brodsky, Mike Rapoport, Lukas Bulwahn, Maciej
     Wieczor-Retman, Max Grobecker, Patryk Wlazlyn, Pawan Gupta, Peter
     Zijlstra, Philip Redkin, Qasim Ijaz, Rik van Riel, Thomas Gleixner,
     Thorsten Blum, Tom Lendacky, Tony Luck, Uros Bizjak, Vitaly
     Kuznetsov, Xin Li, liuye"

* tag 'x86-core-2025-03-22' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (211 commits)
  zstd: Increase DYNAMIC_BMI2 GCC version cutoff from 4.8 to 11.0 to work around compiler segfault
  x86/asm: Make asm export of __ref_stack_chk_guard unconditional
  x86/mm: Only do broadcast flush from reclaim if pages were unmapped
  perf/x86/intel, x86/cpu: Replace Pentium 4 model checks with VFM ones
  perf/x86/intel, x86/cpu: Simplify Intel PMU initialization
  x86/headers: Replace __ASSEMBLY__ with __ASSEMBLER__ in non-UAPI headers
  x86/headers: Replace __ASSEMBLY__ with __ASSEMBLER__ in UAPI headers
  x86/locking/atomic: Improve performance by using asm_inline() for atomic locking instructions
  x86/asm: Use asm_inline() instead of asm() in clwb()
  x86/asm: Use CLFLUSHOPT and CLWB mnemonics in &lt;asm/special_insns.h&gt;
  x86/hweight: Use asm_inline() instead of asm()
  x86/hweight: Use ASM_CALL_CONSTRAINT in inline asm()
  x86/hweight: Use named operands in inline asm()
  x86/stackprotector/64: Only export __ref_stack_chk_guard on CONFIG_SMP
  x86/head/64: Avoid Clang &lt; 17 stack protector in startup code
  x86/kexec: Merge x86_32 and x86_64 code using macros from &lt;asm/asm.h&gt;
  x86/runtime-const: Add the RUNTIME_CONST_PTR assembly macro
  x86/cpu/intel: Limit the non-architectural constant_tsc model checks
  x86/mm/pat: Replace Intel x86_model checks with VFM ones
  x86/cpu/intel: Fix fast string initialization for extended Families
  ...
</pre>
</div>
</content>
</entry>
<entry>
<title>Merge branch 'kvm-arm64/pv-cpuid' into kvmarm/next</title>
<updated>2025-03-19T21:53:16+00:00</updated>
<author>
<name>Oliver Upton</name>
<email>oliver.upton@linux.dev</email>
</author>
<published>2025-03-19T21:53:09+00:00</published>
<link rel='alternate' type='text/html' href='https://git.toradex.cn/cgit/linux-toradex.git/commit/?id=d300b0168ea8fd5022a1413bd37ab63f4e5a7d4d'/>
<id>d300b0168ea8fd5022a1413bd37ab63f4e5a7d4d</id>
<content type='text'>
* kvm-arm64/pv-cpuid:
  : Paravirtualized implementation ID, courtesy of Shameer Kolothum
  :
  : Big-little has historically been a pain in the ass to virtualize. The
  : implementation ID (MIDR, REVIDR, AIDR) of a vCPU can change at the whim
  : of vCPU scheduling. This can be particularly annoying when the guest
  : needs to know the underlying implementation to mitigate errata.
  :
  : "Hyperscalers" face a similar scheduling problem, where VMs may freely
  : migrate between hosts in a pool of heterogenous hardware. And yes, our
  : server-class friends are equally riddled with errata too.
  :
  : In absence of an architected solution to this wart on the ecosystem,
  : introduce support for paravirtualizing the implementation exposed
  : to a VM, allowing the VMM to describe the pool of implementations that a
  : VM may be exposed to due to scheduling/migration.
  :
  : Userspace is expected to intercept and handle these hypercalls using the
  : SMCCC filter UAPI, should it choose to do so.
  smccc: kvm_guest: Fix kernel builds for 32 bit arm
  KVM: selftests: Add test for KVM_REG_ARM_VENDOR_HYP_BMAP_2
  smccc/kvm_guest: Enable errata based on implementation CPUs
  arm64: Make  _midr_in_range_list() an exported function
  KVM: arm64: Introduce KVM_REG_ARM_VENDOR_HYP_BMAP_2
  KVM: arm64: Specify hypercall ABI for retrieving target implementations
  arm64: Modify _midr_range() functions to read MIDR/REVIDR internally

Signed-off-by: Oliver Upton &lt;oliver.upton@linux.dev&gt;
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* kvm-arm64/pv-cpuid:
  : Paravirtualized implementation ID, courtesy of Shameer Kolothum
  :
  : Big-little has historically been a pain in the ass to virtualize. The
  : implementation ID (MIDR, REVIDR, AIDR) of a vCPU can change at the whim
  : of vCPU scheduling. This can be particularly annoying when the guest
  : needs to know the underlying implementation to mitigate errata.
  :
  : "Hyperscalers" face a similar scheduling problem, where VMs may freely
  : migrate between hosts in a pool of heterogenous hardware. And yes, our
  : server-class friends are equally riddled with errata too.
  :
  : In absence of an architected solution to this wart on the ecosystem,
  : introduce support for paravirtualizing the implementation exposed
  : to a VM, allowing the VMM to describe the pool of implementations that a
  : VM may be exposed to due to scheduling/migration.
  :
  : Userspace is expected to intercept and handle these hypercalls using the
  : SMCCC filter UAPI, should it choose to do so.
  smccc: kvm_guest: Fix kernel builds for 32 bit arm
  KVM: selftests: Add test for KVM_REG_ARM_VENDOR_HYP_BMAP_2
  smccc/kvm_guest: Enable errata based on implementation CPUs
  arm64: Make  _midr_in_range_list() an exported function
  KVM: arm64: Introduce KVM_REG_ARM_VENDOR_HYP_BMAP_2
  KVM: arm64: Specify hypercall ABI for retrieving target implementations
  arm64: Modify _midr_range() functions to read MIDR/REVIDR internally

Signed-off-by: Oliver Upton &lt;oliver.upton@linux.dev&gt;
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