linux-stable.git/tools/include, branch v6.18.33

tools/nolibc/printf: Move snprintf length check to callback

2026-05-23T11:06:27+00:00

[ Upstream commit 4045e7b19bbf7338452cda11e64cfe7ae3361964 ]

Move output truncation to the snprintf() callback.
This simplifies the main code and fixes truncation of padded fields.

Add a zero length callback to 'finalise' the buffer rather than
doing it in snprintf() itself.

Fixes: e90ce42e81381 ("tools/nolibc: implement width padding in printf()")
Signed-off-by: David Laight 
Acked-by: Willy Tarreau 
Link: https://patch.msgid.link/20260302101815.3043-3-david.laight.linux@gmail.com
[Thomas: clean up Fixes trailer]
Signed-off-by: Thomas Weißschuh 
Signed-off-by: Sasha Levin

tools/nolibc/printf: Change variables 'c' to 'ch' and 'tmpbuf[]' to 'outbuf[]'

2026-05-23T11:06:27+00:00

[ Upstream commit f675ae28fcdf7db93a8c1a6964f062725b1e06a0 ]

Changing 'c' makes the code slightly easier to read because the variable
stands out from the single character literals (especially 'c').

Change tmpbuf[] to outbuf[] because 'out' points into it.

The following patches pretty much rewrite the function so the
churn is limited.

Signed-off-by: David Laight 
Acked-by: Willy Tarreau 
Link: https://patch.msgid.link/20260223101735.2922-7-david.laight.linux@gmail.com
Signed-off-by: Thomas Weißschuh 
Stable-dep-of: 4045e7b19bbf ("tools/nolibc/printf: Move snprintf length check to callback")
Signed-off-by: Sasha Levin

tools/nolibc: implement %m if errno is not defined

2026-05-23T11:06:26+00:00

[ Upstream commit fbd1b7f6b322a63b21ebbf00c732a17bb8bdb5d4 ]

For improved compatibility, print %m as "unknown error" when nolibc is
compiled using NOLIBC_IGNORE_ERRNO.

Signed-off-by: Benjamin Berg 
Signed-off-by: Thomas Weißschuh 
Stable-dep-of: 4045e7b19bbf ("tools/nolibc/printf: Move snprintf length check to callback")
Signed-off-by: Sasha Levin

tools: Fix bitfield dependency failure

2026-03-04T12:21:19+00:00

[ Upstream commit a537c0da168a08b0b6a7f7bd9e75f4cc8d45ff57 ]

A perf build failure was reported by Thomas Voegtle on stable kernel
v6.6.120:

    CC      tests/sample-parsing.o
    CC      util/intel-pt-decoder/intel-pt-pkt-decoder.o
    CC      util/perf-regs-arch/perf_regs_csky.o
    CC      util/arm-spe-decoder/arm-spe-pkt-decoder.o
    CC      util/perf-regs-arch/perf_regs_loongarch.o
  In file included from util/arm-spe-decoder/arm-spe-pkt-decoder.h:10,
                   from util/arm-spe-decoder/arm-spe-pkt-decoder.c:14:
  /local/git/linux-stable-rc/tools/include/linux/bitfield.h: In function ‘le16_encode_bits’:
  /local/git/linux-stable-rc/tools/include/linux/bitfield.h:166:31: error: implicit declaration of
  function ‘cpu_to_le16’; did you mean ‘htole16’? [-Werror=implicit-function-declaration]
    ____MAKE_OP(le##size,u##size,cpu_to_le##size,le##size##_to_cpu) \
                                 ^~~~~~~~~
  /local/git/linux-stable-rc/tools/include/linux/bitfield.h:149:9: note: in definition of macro
  ‘____MAKE_OP’
    return to((v & field_mask(field)) * field_multiplier(field)); \
           ^~
  /local/git/linux-stable-rc/tools/include/linux/bitfield.h:170:1: note: in expansion of macro
  ‘__MAKE_OP’
   __MAKE_OP(16)

Fix this by including linux/kernel.h, which provides the required
definitions.

The issue was not found on the mainline due to the relevant C files have
included kernel.h.  It'd be good to merge this change on mainline
as well for robustness.

Closes: https://lore.kernel.org/stable/3a44500b-d7c8-179f-61f6-e51cb50d3512@lio96.de/
Fixes: 64d86c03e1441742 ("perf arm-spe: Extend branch operations")
Reported-by: Hamza Mahfooz 
Reported-by: Thomas Voegtle 
Signed-off-by: Leo Yan 
Cc: Greg Kroah-Hartman 
Cc: Ian Rogers 
Cc: James Clark 
Cc: Leo Yan 
Cc: Namhyung Kim 
To: Sasha Levin 
Cc: stable@vger.kernel.org
Signed-off-by: Arnaldo Carvalho de Melo 
Signed-off-by: Sasha Levin

tools/nolibc/dirent: avoid errno in readdir_r

2025-12-18T13:02:43+00:00

[ 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 
Signed-off-by: Thomas Weißschuh 
Signed-off-by: Sasha Levin

tools/nolibc/stdio: let perror work when NOLIBC_IGNORE_ERRNO is set

2025-12-18T13:02:43+00:00

[ 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 
Signed-off-by: Thomas Weißschuh 
Signed-off-by: Sasha Levin

tools/nolibc: x86: fix section mismatch caused by asm "mem*" functions

2025-12-18T13:02:39+00:00

[ 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 
Signed-off-by: Thomas Weißschuh 
Signed-off-by: Sasha Levin

tools/nolibc: handle NULL wstatus argument to waitpid()

2025-12-18T13:02:27+00:00

[ 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 
Acked-by: Willy Tarreau 
Signed-off-by: Thomas Weißschuh 
Signed-off-by: Sasha Levin

tools headers asm: Sync fls headers header with the kernel sources

2025-11-03T16:35:06+00:00

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 
Signed-off-by: Arnaldo Carvalho de Melo

tools headers UAPI: Sync linux/kvm.h with the kernel sources

2025-11-03T16:10:19+00:00

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 
Cc: Fuad Tabba 
Cc: Paolo Bonzini 
Signed-off-by: Arnaldo Carvalho de Melo