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 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 Rust fixes from Miguel Ojeda:
 "Toolchain and infrastructure:

    - Add 'bindgen' target to make UML 32-bit builds work with GCC

    - Disable two Clippy warnings ('collapsible_{if,match}')

  'pin-init' crate:

    - Fix unsoundness issue that created &'static references"

* tag 'rust-fixes-7.1' of git://git.kernel.org/pub/scm/linux/kernel/git/ojeda/linux:
  rust: allow `clippy::collapsible_if` globally
  rust: allow `clippy::collapsible_match` globally
  rust: pin-init: fix incorrect accessor reference lifetime
  rust: pin-init: internal: move alignment check to `make_field_check`
  rust: arch: um: Fix building 32-bit UML with GCC

Similar to `clippy::collapsible_match` (globally allowed in the previous
commit), the `clippy::collapsible_if` lint [1] can make code harder to
read in certain cases.

Thus just let developers decide on their own.

In addition, remove the existing `expect` we had.

Cc: stable@vger.kernel.org # Needed in 6.12.y and later (Rust is pinned in older LTSs).
Suggested-by: Gary Guo <gary@garyguo.net>
Link: https://lore.kernel.org/rust-for-linux/DGROP5CHU1QZ.1OKJRAUZXE9WC@garyguo.net/
Link: https://rust-lang.github.io/rust-clippy/master/index.html#collapsible_if [1]
Reviewed-by: Gary Guo <gary@garyguo.net>
Link: https://patch.msgid.link/20260426144201.227108-2-ojeda@kernel.org
Signed-off-by: Miguel Ojeda <ojeda@kernel.org>