[ Upstream commit 4ada5679f18dbbe92d87c37a842c3368e6ab5e4a ]

Using errno is not possible when NOLIBC_IGNORE_ERRNO is set. Use
sys_lseek instead of lseek as that avoids using errno.

Fixes: 665fa8dea90d ("tools/nolibc: add support for directory access")
Signed-off-by: Benjamin Berg <benjamin.berg@intel.com>
Signed-off-by: Thomas Weißschuh <linux@weissschuh.net>
Signed-off-by: Sasha Levin <sashal@kernel.org>

[ Upstream commit c485ca3aff2442adea4c08ceb5183e671ebed22a ]

There is no errno variable when NOLIBC_IGNORE_ERRNO is defined. As such,
simply print the message with "unknown error" rather than the integer
value of errno.

Fixes: acab7bcdb1bc ("tools/nolibc/stdio: add perror() to report the errno value")
Signed-off-by: Benjamin Berg <benjamin.berg@intel.com>
Signed-off-by: Thomas Weißschuh <linux@weissschuh.net>
Signed-off-by: Sasha Levin <sashal@kernel.org>

[ Upstream commit 2602949b22330f1275138e2b5aea5d49126b9757 ]

I recently got occasional build failures at -Os or -Oz that would always
involve waitpid(), where the assembler would complain about this:

   init.s: Error: .size expression for waitpid.constprop.0 does not evaluate to a constant

And without -fno-asynchronous-unwind-tables it could also spit such
errors:

  init.s:836: Error: CFI instruction used without previous .cfi_startproc
  init.s:838: Error: .cfi_endproc without corresponding .cfi_startproc
  init.s: Error: open CFI at the end of file; missing .cfi_endproc directive

A trimmed down reproducer is as simple as this:

  int main(int argc, char **argv)
  {
        int ret, status;

        if (argc == 0)
                ret = waitpid(-1, &status, 0);
        else
                ret = waitpid(-1, &status, 0);

        return status;
  }

It produces the following asm code on x86_64:

        .text
  .section .text.nolibc_memmove_memcpy
  .weak memmove
  .weak memcpy
  memmove:
  memcpy:
        movq %rdx, %rcx
	(...)
        retq
  .section .text.nolibc_memset
  .weak memset
  memset:
        xchgl %eax, %esi
        movq  %rdx, %rcx
        pushq %rdi
        rep stosb
        popq  %rax
        retq

        .type	waitpid.constprop.0.isra.0, @function
  waitpid.constprop.0.isra.0:
        subq	$8, %rsp
        (...)
        jmp	*.L5(,%rax,8)
        .section	.rodata
        .align 8
        .align 4
  .L5:
        .quad	.L10
        (...)
        .quad	.L4
        .text
  .L10:
        (...)
        .cfi_def_cfa_offset 8
        ret
        .cfi_endproc
  .LFE273:
        .size	waitpid.constprop.0.isra.0, .-waitpid.constprop.0.isra.0

It's a bit dense, but here's the explanation: the compiler has emitted a
".text" statement because it knows it's working in the .text section.

Then, our hand-written asm code for the mem* functions forced the section
to .text.something without the compiler knowing about it, so it thinks
the code is still being emitted for .text. As such, without any .section
statement, the waitpid.constprop.0.isra.0 label is in fact placed in the
previously created section, here .text.nolibc_memset.

The waitpid() function involves a switch/case statement that can be
turned to a jump table, which is what the compiler does with the .rodata
section, and after that it restores .text, which is no longer the
previous .text.nolibc_memset section. Then the CFI statements cross a
section, so does the .size calculation, which explains the error.

While a first approach consisting in placing an explicit ".text" at the
end of these functions was verified to work, it's still unreliable as
it depends on what the compiler remembers having emitted previously. A
better approach is to replace the ".section" with ".pushsection", and
place a ".popsection" at the end, so that these code blocks are agnostic
to where they're placed relative to other blocks.

Fixes: 553845eebd60 ("tools/nolibc: x86-64: Use `rep movsb` for `memcpy()` and `memmove()`")
Fixes: 12108aa8c1a1 ("tools/nolibc: x86-64: Use `rep stosb` for `memset()`")
Signed-off-by: Willy Tarreau <w@1wt.eu>
Signed-off-by: Thomas Weißschuh <linux@weissschuh.net>
Signed-off-by: Sasha Levin <sashal@kernel.org>

[ Upstream commit 812f223fe9be03dc22abb85240b6f075135d2386 ]

wstatus is allowed to be NULL. Avoid a segmentation fault in this case.

Fixes: 0c89abf5ab3f ("tools/nolibc: implement waitpid() in terms of waitid()")
Signed-off-by: Thomas Weißschuh <thomas.weissschuh@linutronix.de>
Acked-by: Willy Tarreau <w@1wt.eu>
Signed-off-by: Thomas Weißschuh <linux@weissschuh.net>
Signed-off-by: Sasha Levin <sashal@kernel.org>

To pick the changes in:

  6606c8c7e8188656 ("bitops: Add __attribute_const__ to generic ffs()-family implementations")

This addresses these tools build warnings:

  Warning: Kernel ABI header differences:
    diff -u tools/include/asm-generic/bitops/__fls.h include/asm-generic/bitops/__fls.h
    diff -u tools/include/asm-generic/bitops/fls.h include/asm-generic/bitops/fls.h
    diff -u tools/include/asm-generic/bitops/fls64.h include/asm-generic/bitops/fls64.h

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

Cc: Kees Cook <kees@kernel.org>
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>

To pick the changes in:

  fe2bf6234e947bf5 ("KVM: guest_memfd: Add INIT_SHARED flag, reject user page faults if not set")
  d2042d8f96ddefde ("KVM: Rework KVM_CAP_GUEST_MEMFD_MMAP into KVM_CAP_GUEST_MEMFD_FLAGS")
  3d3a04fad25a6621 ("KVM: Allow and advertise support for host mmap() on guest_memfd files")

That just rebuilds perf, as these patches don't add any new KVM ioctl to
be harvested for the 'perf trace' ioctl syscall argument beautifiers.

This addresses this perf build warning:

  Warning: Kernel ABI header differences:
    diff -u tools/include/uapi/linux/kvm.h include/uapi/linux/kvm.h

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

Cc: Sean Christopherson <seanjc@google.com>
Cc: Fuad Tabba <tabba@google.com>
Cc: Paolo Bonzini <pbonzini@redhat.com>
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>

Picking the changes from:

  0864197382fa7c8c ("drm: Move drm_gem ioctl kerneldoc to uapi file")
  53096728b8910c69 ("drm: Add DRM prime interface to reassign GEM handle")

Addressing these perf build warnings:

  Warning: Kernel ABI header differences:

Now 'perf trace' and other code that might use the tools/perf/trace/beauty
autogenerated tables will be able to translate this new ioctl command into
a string:

  $ tools/perf/trace/beauty/drm_ioctl.sh > before
  $ cp include/uapi/drm/drm.h tools/include/uapi/drm/drm.h
  $ tools/perf/trace/beauty/drm_ioctl.sh > after
  $ diff -u before after
  --- before	2025-11-03 09:57:34.832553174 -0300
  +++ after	2025-11-03 09:57:47.969409428 -0300
  @@ -111,6 +111,7 @@
   	[0xCF] = "SYNCOBJ_EVENTFD",
   	[0xD0] = "MODE_CLOSEFB",
   	[0xD1] = "SET_CLIENT_NAME",
  +	[0xD2] = "GEM_CHANGE_HANDLE",
   	[DRM_COMMAND_BASE + 0x00] = "I915_INIT",
   	[DRM_COMMAND_BASE + 0x01] = "I915_FLUSH",
   	[DRM_COMMAND_BASE + 0x02] = "I915_FLIP",
  $

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

Cc: Christian König <christian.koenig@amd.com>
Cc: David Francis <David.Francis@amd.com>
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>

Pull more x86 updates from Borislav Petkov:

 - Remove a bunch of asm implementing condition flags testing in KVM's
   emulator in favor of int3_emulate_jcc() which is written in C

 - Replace KVM fastops with C-based stubs which avoids problems with the
   fastop infra related to latter not adhering to the C ABI due to their
   special calling convention and, more importantly, bypassing compiler
   control-flow integrity checking because they're written in asm

 - Remove wrongly used static branches and other ugliness accumulated
   over time in hyperv's hypercall implementation with a proper static
   function call to the correct hypervisor call variant

 - Add some fixes and modifications to allow running FRED-enabled
   kernels in KVM even on non-FRED hardware

 - Add kCFI improvements like validating indirect calls and prepare for
   enabling kCFI with GCC. Add cmdline params documentation and other
   code cleanups

 - Use the single-byte 0xd6 insn as the official #UD single-byte
   undefined opcode instruction as agreed upon by both x86 vendors

 - Other smaller cleanups and touchups all over the place

* tag 'x86_core_for_v6.18_rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (24 commits)
  x86,retpoline: Optimize patch_retpoline()
  x86,ibt: Use UDB instead of 0xEA
  x86/cfi: Remove __noinitretpoline and __noretpoline
  x86/cfi: Add "debug" option to "cfi=" bootparam
  x86/cfi: Standardize on common "CFI:" prefix for CFI reports
  x86/cfi: Document the "cfi=" bootparam options
  x86/traps: Clarify KCFI instruction layout
  compiler_types.h: Move __nocfi out of compiler-specific header
  objtool: Validate kCFI calls
  x86/fred: KVM: VMX: Always use FRED for IRQs when CONFIG_X86_FRED=y
  x86/fred: Play nice with invoking asm_fred_entry_from_kvm() on non-FRED hardware
  x86/fred: Install system vector handlers even if FRED isn't fully enabled
  x86/hyperv: Use direct call to hypercall-page
  x86/hyperv: Clean up hv_do_hypercall()
  KVM: x86: Remove fastops
  KVM: x86: Convert em_salc() to C
  KVM: x86: Introduce EM_ASM_3WCL
  KVM: x86: Introduce EM_ASM_1SRC2
  KVM: x86: Introduce EM_ASM_2CL
  KVM: x86: Introduce EM_ASM_2W
  ...

Pull bpf fixes from Alexei Starovoitov:

 - Finish constification of 1st parameter of bpf_d_path() (Rong Tao)

 - Harden userspace-supplied xdp_desc validation (Alexander Lobakin)

 - Fix metadata_dst leak in __bpf_redirect_neigh_v{4,6}() (Daniel
   Borkmann)

 - Fix undefined behavior in {get,put}_unaligned_be32() (Eric Biggers)

 - Use correct context to unpin bpf hash map with special types (KaFai
   Wan)

* tag 'bpf-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/bpf/bpf:
  selftests/bpf: Add test for unpinning htab with internal timer struct
  bpf: Avoid RCU context warning when unpinning htab with internal structs
  xsk: Harden userspace-supplied xdp_desc validation
  bpf: Fix metadata_dst leak __bpf_redirect_neigh_v{4,6}
  libbpf: Fix undefined behavior in {get,put}_unaligned_be32()
  bpf: Finish constification of 1st parameter of bpf_d_path()

Pull perf tools updates from Arnaldo Carvalho de Melo:

 - Extended 'perf annotate' with DWARF type information
   (--code-with-type) integration in the TUI, including a 'T'
   hotkey to toggle it

 - Enhanced 'perf bench mem' with new mmap() workloads and control
   over page/chunk sizes

 - Fix 'perf stat' error handling to correctly display unsupported
   events

 - Improved support for Clang cross-compilation

 - Refactored LLVM and Capstone disasm for modularity

 - Introduced the :X modifier to exclude an event from automatic
   regrouping

 - Adjusted KVM sampling defaults to use the "cycles" event to prevent
   failures

 - Added comprehensive support for decoding PowerPC Dispatch Trace Log
   (DTL)

 - Updated Arm SPE tracing logic for better analysis of memory and snoop
   details

 - Synchronized Intel PMU events and metrics with TMA 5.1 across
   multiple processor generations

 - Converted dependencies like libperl and libtracefs to be opt-in

 - Handle more Rust symbols in kallsyms ('N', debugging)

 - Improve the python binding to allow for python based tools to use
   more of the libraries, add a 'ilist' utility to test those new
   bindings

 - Various 'perf test' fixes

 - Kan Liang no longer a perf tools reviewer

* tag 'perf-tools-for-v6.18-1-2025-10-08' of git://git.kernel.org/pub/scm/linux/kernel/git/perf/perf-tools: (192 commits)
  perf tools: Fix arm64 libjvmti build by generating unistd_64.h
  perf tests: Don't retest sections in "Object code reading"
  perf docs: Document building with Clang
  perf build: Support build with clang
  perf test coresight: Dismiss clang warning for unroll loop thread
  perf test coresight: Dismiss clang warning for thread loop
  perf test coresight: Dismiss clang warning for memcpy thread
  perf build: Disable thread safety analysis for perl header
  perf build: Correct CROSS_ARCH for clang
  perf python: split Clang options when invoking Popen
  tools build: Align warning options with perf
  perf disasm: Remove unused evsel from 'struct annotate_args'
  perf srcline: Fallback between addr2line implementations
  perf disasm: Make ins__scnprintf() and ins__is_nop() static
  perf dso: Clean up read_symbol() error handling
  perf dso: Support BPF programs in dso__read_symbol()
  perf dso: Move read_symbol() from llvm/capstone to dso
  perf llvm: Reduce LLVM initialization
  perf check: Add libLLVM feature
  perf parse-events: Fix parsing of >30kb event strings
  ...