linux.git/scripts, branch v6.1.98

kbuild: fix short log for AS in link-vmlinux.sh

2024-07-11T10:47:18+00:00

[ Upstream commit 3430f65d6130ccbc86f0ff45642eeb9e2032a600 ]

In convention, short logs print the output file, not the input file.

Let's change the suffix for 'AS' since it assembles *.S into *.o.

[Before]

  LD      .tmp_vmlinux.kallsyms1
  NM      .tmp_vmlinux.kallsyms1.syms
  KSYMS   .tmp_vmlinux.kallsyms1.S
  AS      .tmp_vmlinux.kallsyms1.S
  LD      .tmp_vmlinux.kallsyms2
  NM      .tmp_vmlinux.kallsyms2.syms
  KSYMS   .tmp_vmlinux.kallsyms2.S
  AS      .tmp_vmlinux.kallsyms2.S
  LD      vmlinux

[After]

  LD      .tmp_vmlinux.kallsyms1
  NM      .tmp_vmlinux.kallsyms1.syms
  KSYMS   .tmp_vmlinux.kallsyms1.S
  AS      .tmp_vmlinux.kallsyms1.o
  LD      .tmp_vmlinux.kallsyms2
  NM      .tmp_vmlinux.kallsyms2.syms
  KSYMS   .tmp_vmlinux.kallsyms2.S
  AS      .tmp_vmlinux.kallsyms2.o
  LD      vmlinux

Signed-off-by: Masahiro Yamada 
Signed-off-by: Sasha Levin

kbuild: Install dtb files as 0644 in Makefile.dtbinst

2024-07-05T07:31:57+00:00

commit 9cc5f3bf63aa98bd7cc7ce8a8599077fde13283e upstream.

The compiled dtb files aren't executable, so install them with 0644 as their
permission mode, instead of defaulting to 0755 for the permission mode and
installing them with the executable bits set.

Some Linux distributions, including Debian, [1][2][3] already include fixes
in their kernel package build recipes to change the dtb file permissions to
0644 in their kernel packages.  These changes, when additionally propagated
into the long-term kernel versions, will allow such distributions to remove
their downstream fixes.

[1] https://salsa.debian.org/kernel-team/linux/-/merge_requests/642
[2] https://salsa.debian.org/kernel-team/linux/-/merge_requests/749
[3] https://salsa.debian.org/kernel-team/linux/-/blob/debian/6.8.12-1/debian/rules.real#L193

Cc: Diederik de Haas 
Cc: 
Fixes: aefd80307a05 ("kbuild: refactor Makefile.dtbinst more")
Signed-off-by: Dragan Simic 
Reviewed-by: Nicolas Schier 
Signed-off-by: Masahiro Yamada 
Signed-off-by: Greg Kroah-Hartman

scripts/gdb: fix SB_* constants parsing

2024-06-16T11:41:32+00:00

commit 6a59cb5158bff13b80f116305155fbe4967a5010 upstream.

--0000000000009a0c9905fd9173ad
Content-Transfer-Encoding: 8bit

After f15afbd34d8f ("fs: fix undefined behavior in bit shift for
SB_NOUSER") the constants were changed from plain integers which
LX_VALUE() can parse to constants using the BIT() macro which causes the
following:

Reading symbols from build/linux-custom/vmlinux...done.
Traceback (most recent call last):
  File "/home/fainelli/work/buildroot/output/arm64/build/linux-custom/vmlinux-gdb.py", line 25, in 
    import linux.constants
  File "/home/fainelli/work/buildroot/output/arm64/build/linux-custom/scripts/gdb/linux/constants.py", line 5
    LX_SB_RDONLY = ((((1UL))) << (0))

Use LX_GDBPARSED() which does not suffer from that issue.

f15afbd34d8f ("fs: fix undefined behavior in bit shift for SB_NOUSER")
Link: https://lkml.kernel.org/r/20230607221337.2781730-1-florian.fainelli@broadcom.com
Signed-off-by: Florian Fainelli 
Acked-by: Christian Brauner 
Cc: Hao Ge 
Cc: Jan Kiszka 
Cc: Kieran Bingham 
Cc: Luis Chamberlain 
Cc: Pankaj Raghav 
Signed-off-by: Andrew Morton 
Signed-off-by: Florian Fainelli 
Signed-off-by: Greg Kroah-Hartman

kconfig: fix comparison to constant symbols, 'm', 'n'

2024-06-12T09:03:58+00:00

[ Upstream commit aabdc960a283ba78086b0bf66ee74326f49e218e ]

Currently, comparisons to 'm' or 'n' result in incorrect output.

[Test Code]

    config MODULES
            def_bool y
            modules

    config A
            def_tristate m

    config B
            def_bool A > n

CONFIG_B is unset, while CONFIG_B=y is expected.

The reason for the issue is because Kconfig compares the tristate values
as strings.

Currently, the .type fields in the constant symbol definitions,
symbol_{yes,mod,no} are unspecified, i.e., S_UNKNOWN.

When expr_calc_value() evaluates 'A > n', it checks the types of 'A' and
'n' to determine how to compare them.

The left-hand side, 'A', is a tristate symbol with a value of 'm', which
corresponds to a numeric value of 1. (Internally, 'y', 'm', and 'n' are
represented as 2, 1, and 0, respectively.)

The right-hand side, 'n', has an unknown type, so it is treated as the
string "n" during the comparison.

expr_calc_value() compares two values numerically only when both can
have numeric values. Otherwise, they are compared as strings.

    symbol    numeric value    ASCII code
    -------------------------------------
      y           2             0x79
      m           1             0x6d
      n           0             0x6e

'm' is greater than 'n' if compared numerically (since 1 is greater
than 0), but smaller than 'n' if compared as strings (since the ASCII
code 0x6d is smaller than 0x6e).

Specifying .type=S_TRISTATE for symbol_{yes,mod,no} fixes the above
test code.

Doing so, however, would cause a regression to the following test code.

[Test Code 2]

    config MODULES
            def_bool n
            modules

    config A
            def_tristate n

    config B
            def_bool A = m

You would get CONFIG_B=y, while CONFIG_B should not be set.

The reason is because sym_get_string_value() turns 'm' into 'n' when the
module feature is disabled. Consequently, expr_calc_value() evaluates
'A = n' instead of 'A = m'. This oddity has been hidden because the type
of 'm' was previously S_UNKNOWN instead of S_TRISTATE.

sym_get_string_value() should not tweak the string because the tristate
value has already been correctly calculated. There is no reason to
return the string "n" where its tristate value is mod.

Fixes: 31847b67bec0 ("kconfig: allow use of relations other than (in)equality")
Signed-off-by: Masahiro Yamada 
Signed-off-by: Sasha Levin

btf, scripts: rust: drop is_rust_module.sh

2024-05-17T09:56:17+00:00

commit 41bdc6decda074afc4d8f8ba44c69b08d0e9aff6 upstream.

With commit c1177979af9c ("btf, scripts: Exclude Rust CUs with pahole")
we are now able to use pahole directly to identify Rust compilation
units (CUs) and exclude them from generating BTF debugging information
(when DEBUG_INFO_BTF is enabled).

And if pahole doesn't support the --lang-exclude flag, we can't enable
both RUST and DEBUG_INFO_BTF at the same time.

So, in any case, the script is_rust_module.sh is just redundant and we
can drop it.

NOTE: we may also be able to drop the "Rust loadable module" mark
inside Rust modules, but it seems safer to keep it for now to make sure
we are not breaking any external tool that may potentially rely on it.

Signed-off-by: Andrea Righi 
Reviewed-by: Nathan Chancellor 
Tested-by: Eric Curtin 
Reviewed-by: Eric Curtin 
Reviewed-by: Neal Gompa 
Reviewed-by: Masahiro Yamada 
Reviewed-by: Martin Rodriguez Reboredo 
Acked-by: Daniel Xu 
Link: https://lore.kernel.org/r/20230704052136.155445-1-andrea.righi@canonical.com
[ Picked the `Reviewed-by`s from the old patch too. ]
Signed-off-by: Miguel Ojeda 
Signed-off-by: Greg Kroah-Hartman

rust: fix regexp in scripts/is_rust_module.sh

2024-05-17T09:56:16+00:00

commit ccc4505454db10402d5284f22d8b7db62e636fc5 upstream.

nm can use "R" or "r" to show read-only data sections, but
scripts/is_rust_module.sh can only recognize "r", so with some versions
of binutils it can fail to detect if a module is a Rust module or not.

Right now we're using this script only to determine if we need to skip
BTF generation (that is disabled globally if CONFIG_RUST is enabled),
but it's still nice to fix this script to do the proper job.

Moreover, with this patch applied I can also relax the constraint of
"RUST depends on !DEBUG_INFO_BTF" and build a kernel with Rust and BTF
enabled at the same time (of course BTF generation is still skipped for
Rust modules).

[ Miguel: The actual reason is likely to be a change on the Rust
  compiler between 1.61.0 and 1.62.0:

    echo '#[used] static S: () = ();' |
        rustup run 1.61.0 rustc --emit=obj --crate-type=lib - &&
        nm rust_out.o

    echo '#[used] static S: () = ();' |
        rustup run 1.62.0 rustc --emit=obj --crate-type=lib - &&
        nm rust_out.o

  Gives:

    0000000000000000 r _ZN8rust_out1S17h48027ce0da975467E
    0000000000000000 R _ZN8rust_out1S17h58e1f3d9c0e97cefE

  See https://godbolt.org/z/KE6jneoo4. ]

Signed-off-by: Andrea Righi 
Reviewed-by: Vincenzo Palazzo 
Reviewed-by: Eric Curtin 
Reviewed-by: Martin Rodriguez Reboredo 
Signed-off-by: Miguel Ojeda 
Signed-off-by: Greg Kroah-Hartman

kbuild: rust: avoid creating temporary files

2024-05-17T09:56:10+00:00

[ Upstream commit df01b7cfcef08bf3fdcac2909d0e1910781d6bfd ]

`rustc` outputs by default the temporary files (i.e. the ones saved
by `-Csave-temps`, such as `*.rcgu*` files) in the current working
directory when `-o` and `--out-dir` are not given (even if
`--emit=x=path` is given, i.e. it does not use those for temporaries).

Since out-of-tree modules are compiled from the `linux` tree,
`rustc` then tries to create them there, which may not be accessible.

Thus pass `--out-dir` explicitly, even if it is just for the temporary
files.

Similarly, do so for Rust host programs too.

Reported-by: Raphael Nestler 
Closes: https://github.com/Rust-for-Linux/linux/issues/1015
Reported-by: Andrea Righi 
Tested-by: Raphael Nestler  # non-hostprogs
Tested-by: Andrea Righi  # non-hostprogs
Fixes: 295d8398c67e ("kbuild: specify output names separately for each emission type from rustc")
Cc: stable@vger.kernel.org
Signed-off-by: Miguel Ojeda 
Tested-by: Martin Rodriguez Reboredo 
Signed-off-by: Masahiro Yamada 
Signed-off-by: Sasha Levin

kbuild: Disable KCSAN for autogenerated *.mod.c intermediaries

2024-05-17T09:56:05+00:00

[ Upstream commit 54babdc0343fff2f32dfaafaaa9e42c4db278204 ]

When KCSAN and CONSTRUCTORS are enabled, one can trigger the

  "Unpatched return thunk in use. This should not happen!"

catch-all warning.

Usually, when objtool runs on the .o objects, it does generate a section
.return_sites which contains all offsets in the objects to the return
thunks of the functions present there. Those return thunks then get
patched at runtime by the alternatives.

KCSAN and CONSTRUCTORS add this to the object file's .text.startup
section:

  -------------------
  Disassembly of section .text.startup:

  ...

  0000000000000010 <_sub_I_00099_0>:
    10:   f3 0f 1e fa             endbr64
    14:   e8 00 00 00 00          call   19 <_sub_I_00099_0+0x9>
                          15: R_X86_64_PLT32      __tsan_init-0x4
    19:   e9 00 00 00 00          jmp    1e <__UNIQUE_ID___addressable_cryptd_alloc_aead349+0x6>
                          1a: R_X86_64_PLT32      __x86_return_thunk-0x4
  -------------------

which, if it is built as a module goes through the intermediary stage of
creating a .mod.c file which, when translated, receives a second
constructor:

  -------------------
  Disassembly of section .text.startup:

  0000000000000010 <_sub_I_00099_0>:
    10:   f3 0f 1e fa             endbr64
    14:   e8 00 00 00 00          call   19 <_sub_I_00099_0+0x9>
                          15: R_X86_64_PLT32      __tsan_init-0x4
    19:   e9 00 00 00 00          jmp    1e <_sub_I_00099_0+0xe>
                          1a: R_X86_64_PLT32      __x86_return_thunk-0x4

  ...

  0000000000000030 <_sub_I_00099_0>:
    30:   f3 0f 1e fa             endbr64
    34:   e8 00 00 00 00          call   39 <_sub_I_00099_0+0x9>
                          35: R_X86_64_PLT32      __tsan_init-0x4
    39:   e9 00 00 00 00          jmp    3e <__ksymtab_cryptd_alloc_ahash+0x2>
                          3a: R_X86_64_PLT32      __x86_return_thunk-0x4
  -------------------

in the .ko file.

Objtool has run already so that second constructor's return thunk cannot
be added to the .return_sites section and thus the return thunk remains
unpatched and the warning rightfully fires.

Drop KCSAN flags from the mod.c generation stage as those constructors
do not contain data races one would be interested about.

Debugged together with David Kaplan  and Nikolay
Borisov .

Reported-by: Paul Menzel 
Closes: https://lore.kernel.org/r/0851a207-7143-417e-be31-8bf2b3afb57d@molgen.mpg.de
Signed-off-by: Borislav Petkov (AMD) 
Tested-by: Paul Menzel  # Dell XPS 13
Reviewed-by: Nikolay Borisov 
Reviewed-by: Marco Elver 
Signed-off-by: Masahiro Yamada 
Signed-off-by: Sasha Levin

kbuild: specify output names separately for each emission type from rustc

2024-05-17T09:55:53+00:00

[ Upstream commit 295d8398c67e314d99bb070f38883f83fe94a97a ]

In Kbuild, two different rules must not write to the same file, but
it happens when compiling rust source files.

For example, set CONFIG_SAMPLE_RUST_MINIMAL=m and run the following:

  $ make -j$(nproc) samples/rust/rust_minimal.o samples/rust/rust_minimal.rsi \
                    samples/rust/rust_minimal.s samples/rust/rust_minimal.ll
    [snip]
    RUSTC [M] samples/rust/rust_minimal.o
    RUSTC [M] samples/rust/rust_minimal.rsi
    RUSTC [M] samples/rust/rust_minimal.s
    RUSTC [M] samples/rust/rust_minimal.ll
  mv: cannot stat 'samples/rust/rust_minimal.d': No such file or directory
  make[3]: *** [scripts/Makefile.build:334: samples/rust/rust_minimal.ll] Error 1
  make[3]: *** Waiting for unfinished jobs....
  mv: cannot stat 'samples/rust/rust_minimal.d': No such file or directory
  make[3]: *** [scripts/Makefile.build:309: samples/rust/rust_minimal.o] Error 1
  mv: cannot stat 'samples/rust/rust_minimal.d': No such file or directory
  make[3]: *** [scripts/Makefile.build:326: samples/rust/rust_minimal.s] Error 1
  make[2]: *** [scripts/Makefile.build:504: samples/rust] Error 2
  make[1]: *** [scripts/Makefile.build:504: samples] Error 2
  make: *** [Makefile:2008: .] Error 2

The reason for the error is that 4 threads running in parallel renames
the same file, samples/rust/rust_minimal.d.

This does not happen when compiling C or assembly files because
-Wp,-MMD,$(depfile) explicitly specifies the dependency filepath.
$(depfile) is a unique path for each target.

Currently, rustc is only given --out-dir and --emit=
So, all the rust build rules output the dep-info into the default
.d, which causes the path conflict.

Fortunately, the --emit option is able to specify the output path
individually, with the form --emit==.

Add --emit=dep-info=$(depfile) to the common part. Also, remove the
redundant --out-dir because the output path is specified for each type.

The code gets much cleaner because we do not need to rename *.d files.

Signed-off-by: Masahiro Yamada 
Reviewed-by: Miguel Ojeda 
Tested-by: Miguel Ojeda 
Reviewed-by: Vincenzo Palazzo 
Stable-dep-of: ded103c7eb23 ("kbuild: rust: force `alloc` extern to allow "empty" Rust files")
Signed-off-by: Sasha Levin

kbuild: refactor host*_flags

2024-05-17T09:55:53+00:00

[ Upstream commit 16169a47d5c36046041527faafb5a3f5c86701c6 ]

Remove _host*_flags. No functional change is intended.

Signed-off-by: Masahiro Yamada 
Reviewed-by: Miguel Ojeda 
Tested-by: Miguel Ojeda 
Stable-dep-of: ded103c7eb23 ("kbuild: rust: force `alloc` extern to allow "empty" Rust files")
Signed-off-by: Sasha Levin