[ Upstream commit f3048888ea62ac1c573db91e74e0dcabe058e89f ]

If a build error occurs and the user hits Ctrl-C while a large patch is
being reverted during cleanup, the cleanup EXIT trap gets re-triggered
and tries to re-revert the already partially-reverted patch.  That
causes 'patch -R' to repeatedly prompt

  "Unreversed patch detected!  Ignore -R? [n]"

for each already-reverted hunk, with no way to break out.

Fix it by adding '--force' to the patch revert command in
revert_patch(), which causes it to silently ignore already-reverted
hunks.  And ignore errors, as the cleanup is always best-effort.

For similar reasons, add to APPLIED_PATCHES before (rather than after)
applying the patch in apply_patch() so an interrupted apply will also
get cleaned up.

Fixes: d36a7343f4ba ("livepatch/klp-build: switch to GNU patch and recountdiff")
Acked-by: Song Liu <song@kernel.org>
Signed-off-by: Josh Poimboeuf <jpoimboe@kernel.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>

[ Upstream commit ba77fe55781a2464f68b6c13b4b31d05abd2abcf ]

The klp-build -f/--show-first-changed feature uses diff to compare
checksum log lines between original and patched objects.  However, diff
compares entire lines, including the offset field.  When a function is
at a different section offset, the offset field differs even though the
instruction checksum is identical, causing the wrong instruction to be
printed.

Only compare the checksum field when looking for the first changed
instruction.  Also print both the original and patched offsets when they
differ.

Fixes: 78be9facfb5e ("livepatch/klp-build: Add --show-first-changed option to show function divergence")
Acked-by: Song Liu <song@kernel.org>
Signed-off-by: Josh Poimboeuf <jpoimboe@kernel.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>

[ Upstream commit cc39ccce7d5bc623100f07dcda070cef1bf690f6 ]

If .config is out of date with the kernel source, 'make syncconfig'
hangs while waiting for user input on new config options.  Detect the
mismatch and return an error.

Fixes: 6f93f7b06810 ("livepatch/klp-build: Fix inconsistent kernel version")
Acked-by: Song Liu <song@kernel.org>
Signed-off-by: Josh Poimboeuf <jpoimboe@kernel.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>

[ Upstream commit b9d21c32dca2167a614e66c9e27999b9e1c33d55 ]

In conf_askvalue(), the 'def' argument (retrieved via sym_get_string_value)
can be NULL. While current call sites ensure that 'def' is valid,
calling printf("%s\n", def) is technically undefined behavior and could
lead to a segmentation fault on certain libc implementations if the
function were called with a NULL pointer in the future.

Improve the robustness of conf_askvalue() by providing an empty string
as a fallback.

Additionally, remove the redundant re-initialization of the 'line'
buffer inside the !sym_is_changeable(sym) block, as it is already
properly initialized at the function entry.

Fixes: 1da177e4c3f4 ("Linux-2.6.12-rc2")
Signed-off-by: Xingjing Deng <micro6947@gmail.com>
Reviewed-by: Nathan Chancellor <nathan@kernel.org>
Link: https://patch.msgid.link/20260306021709.27068-1-micro6947@gmail.com
Signed-off-by: Nathan Chancellor <nathan@kernel.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>

commit ac4d1caa82d487e7ed46d0597da1adc9c1a51c70 upstream.

The `-> Result<(), impl core::fmt::Debug>` string is generated by rustdoc
and by adding "::" into the string it no longer finds anything, making
the line useless.

Remove the "::" in the pattern. Omit it in the replacement too, for
consistency with upstream rustdoc.

Fixes: de7cd3e4d638 ("rust: use absolute paths in macros referencing core and kernel")
Signed-off-by: Gary Guo <gary@garyguo.net>
Cc: stable@vger.kernel.org
Link: https://patch.msgid.link/20260616132559.2245814-1-gary@kernel.org
[ Added link in code comment to `rustdoc`'s 1.87 PR that fully qualified
  it for context. Improved comments for consistency. Reworded to drop
  changelog and to fix typo. - Miguel ]
Signed-off-by: Miguel Ojeda <ojeda@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

Pull Rust fixes from Miguel Ojeda:
 "Toolchain and infrastructure:

   - Fix 'rustc-option' (the Makefile one) when cross-compiling that
     leads to build or boot failures in certain configs

   - Work around a Rust compiler bug (already fixed for Rust 1.98.0)
     thats lead to boot failures in certain configs due to missing
     'uwtable' LLVM module flags

   - Support a Rust compiler change (starting with Rust 1.98.0) in the
     unstable target specification JSON files

   - Forbid Rust + arm + KASAN configs, which do not build

  'kernel' crate:

   - Fix NOMMU build by adding a missing helper"

* tag 'rust-fixes-7.1-2' of git://git.kernel.org/pub/scm/linux/kernel/git/ojeda/linux:
  rust: x86: support Rust >= 1.98.0 target spec
  rust: arm64: set uwtable llvm module flag for CONFIG_UNWIND_TABLES
  rust: helpers: add is_vmalloc_addr wrapper for NOMMU builds
  rust: kasan/kbuild: fix rustc-option when cross-compiling
  ARM: Do not select HAVE_RUST when KASAN is enabled

The err_repeated_inc test was added with an expected stderr fixture
that does not match the diagnostic printed by kconfig.

Running "make testconfig" currently fails in that test even though the
parser reports the duplicated include correctly:

  [stderr]
  Kconfig.inc1:4: error: repeated inclusion of Kconfig.inc3
  Kconfig.inc2:3: note: location of first inclusion of Kconfig.inc3

The fixture expects "Repeated" and "Location" with capital letters, but
the diagnostic emitted by scripts/kconfig/util.c uses lowercase words.
Update the fixture to match the real message.

Fixes: 102d712ded3e ("kconfig: Error out on duplicated kconfig inclusion")
Signed-off-by: Zhou Yuhang <zhouyuhang@kylinos.cn>
Tested-by: Nicolas Schier <nsc@kernel.org>
Reviewed-by: Nathan Chancellor <nathan@kernel.org>
Link: https://patch.msgid.link/20260520070800.2265479-1-zhouyuhang1010@163.com
Signed-off-by: Nicolas Schier <nsc@kernel.org>

Starting with Rust 1.98.0 (expected 2026-08-20), the target spec will not
support `x86-softfloat` anymore [1]. Instead, `softfloat` should be used,
which is an alias. Otherwise, one gets:

    error: error loading target specification: rustc-abi: invalid rustc abi: 'x86-softfloat'. allowed values: 'x86-sse2', 'softfloat' at line 3 column 32
      |
      = help: run `rustc --print target-list` for a list of built-in targets

Thus conditionally use one or the other depending on the version.

The alias has existed since Rust 1.95.0 (released 2026-04-16) [2], but
use the newer version instead to avoid changing how the build works for
existing compilers, at least until more testing takes place.

Cc: Ralf Jung <post@ralfj.de>
Cc: stable@vger.kernel.org # Needed in 6.12.y and later (Rust is pinned in older LTSs).
Link: https://github.com/rust-lang/rust/pull/157151 [1]
Link: https://github.com/rust-lang/rust/pull/151154 [2]
Reviewed-by: Alice Ryhl <aliceryhl@google.com>
Link: https://patch.msgid.link/20260530114925.260754-1-ojeda@kernel.org
Signed-off-by: Miguel Ojeda <ojeda@kernel.org>

The Makefile version of rustc-option currently checks whether the option
exists for the host target instead of the target actually being compiled
for. It was done this way in commit 46e24a545cdb ("rust: kasan/kbuild:
fix missing flags on first build") to avoid a circular dependency on
target.json. However, because of this, rustc-option currently does not
function when cross-compiling from x86_64 to aarch64 if
CONFIG_SHADOW_CALL_STACK is enabled. This is because KBUILD_RUSTFLAGS
contains -Zfixed-x18 under this configuration. Since that flag does not
exist on the host target, rustc-option runs into a compilation failure
every time, leading to all flags being rejected as unsupported.

To fix this, update rustc-option to pass a --target parameter so that
the host target is not used. For targets using target.json, use a
built-in target that is as close as possible to the target created with
target.json to avoid the circular dependency on target.json.

One scenario where this causes a boot failure:
* Cross-compiled from x86_64 to aarch64.
* With CONFIG_SHADOW_CALL_STACK=y
* With CONFIG_KASAN_SW_TAGS=y
* With CONFIG_KASAN_INLINE=n
Then the resulting kernel image will fail to boot when it first calls
into Rust code with a crash along the lines of "Unable to handle kernel
paging request at virtual address 0ffffffc08541796". This is because the
call threshold is not specified, so rustc will inline kasan operations,
but the kasan shadow offset is not specified, which leads to the inlined
kasan instructions being incorrect.

Note that the -Zsanitizer=kernel-hwaddress parameter itself does not
lead to a rustc-option failure despite being aarch64-specific because
RUSTFLAGS_KASAN has not yet been added to KBUILD_RUSTFLAGS when
rustc-option is evaluated by the kasan Makefile.

Cc: stable@vger.kernel.org
Fixes: 46e24a545cdb ("rust: kasan/kbuild: fix missing flags on first build")
Signed-off-by: Alice Ryhl <aliceryhl@google.com>
Link: https://patch.msgid.link/20260507-rustc-option-cross-v2-1-2f650a49c2b5@google.com
[ Edited slightly:
    - Reset variable to avoid using the environment.
    - Use a simply expanded variable flavor for simplicity.
    - Export variable so that behavior in sub-`make`s is consistent.

  This matches other variables. - Miguel ]
Signed-off-by: Miguel Ojeda <ojeda@kernel.org>

Pull Kbuild fixes from Nicolas Schier:

 - modpost: prevent stack buffer overflow in do_input_entry() and
   do_dmi_entry()

   Defensively replace unbound sprintf() calls in file2alias to prevent
   silent stack overflows and detect alias name overflows with proper
   error message.

 - kbuild: pacman-pkg: make "rc" releases adhere to pacman versioning
   scheme

   Enable smooth upgrades from "rc" releases w/ pacman packages.

* tag 'kbuild-fixes-7.1-2' of git://git.kernel.org/pub/scm/linux/kernel/git/kbuild/linux:
  kbuild: pacman-pkg: make "rc" releases adhere to pacman versioning scheme
  modpost: prevent stack buffer overflow in do_input_entry() and do_dmi_entry()