rust: alloc: add `Vec` to prelude

Now that we removed `VecExt` and the corresponding includes in
prelude.rs, add the new kernel `Vec` type instead.

Reviewed-by: Alice Ryhl <[email protected]>
Reviewed-by: Benno Lossin <[email protected]>
Reviewed-by: Gary Guo <[email protected]>
Signed-off-by: Danilo Krummrich <[email protected]>
Link: https://lore.kernel.org/r/[email protected]
Signed-off-by: Miguel Ojeda <[email protected]>

rust: alloc: remove `VecExt` extension

Now that all existing `Vec` users were moved to the kernel `Vec` type,
remove the `VecExt` extension.

Reviewed-by: Alice Ryhl <[email protected]>
Reviewed-by: Benno Lossin <[email protected]>
Reviewed-by: Gary Guo <[email protected]>
Signed-off-by: Danilo Krummrich <[email protected]>
Link: https://lore.kernel.org/r/[email protected]
Signed-off-by: Miguel Ojeda <[email protected]>

rust: treewide: switch to the kernel `Vec` type

Now that we got the kernel `Vec` in place, convert all existing `Vec`
users to make use of it.

Reviewed-by: Alice Ryhl <[email protected]>
Reviewed-by: Benno Lossin <[email protected]>
Reviewed-by: Gary Guo <[email protected]>
Signed-off-by: Danilo Krummrich <[email protected]>
Link: https://lore.kernel.org/r/[email protected]
[ Converted `kasan_test_rust.rs` too, as discussed. - Miguel ]
Signed-off-by: Miguel Ojeda <[email protected]>

rust: alloc: implement `collect` for `IntoIter`

Currently, we can't implement `FromIterator`. There are a couple of
issues with this trait in the kernel, namely:

  - Rust's specialization feature is unstable. This prevents us to
    optimize for the special case where `I::IntoIter` equals `Vec`'s
    `IntoIter` type.
  - We also can't use `I::IntoIter`'s type ID either to work around this,
    since `FromIterator` doesn't require this type to be `'static`.
  - `FromIterator::from_iter` does return `Self` instead of
    `Result<Self, AllocError>`, hence we can't properly handle allocation
    failures.
  - Neither `Iterator::collect` nor `FromIterator::from_iter` can handle
    additional allocation flags.

Instead, provide `IntoIter::collect`, such that we can at least convert
`IntoIter` into a `Vec` again.

Reviewed-by: Alice Ryhl <[email protected]>
Reviewed-by: Benno Lossin <[email protected]>
Signed-off-by: Danilo Krummrich <[email protected]>
Link: https://lore.kernel.org/r/[email protected]
[ Added newline in documentation, changed case of section to be
  consistent with an existing one, fixed typo. - Miguel ]
Signed-off-by: Miguel Ojeda <[email protected]>

rust: alloc: implement `IntoIterator` for `Vec`

Implement `IntoIterator` for `Vec`, `Vec`'s `IntoIter` type, as well as
`Iterator` for `IntoIter`.

`Vec::into_iter` disassembles the `Vec` into its raw parts; additionally,
`IntoIter` keeps track of a separate pointer, which is incremented
correspondingly as the iterator advances, while the length, or the count
of elements, is decremented.

This also means that `IntoIter` takes the ownership of the backing
buffer and is responsible to drop the remaining elements and free the
backing buffer, if it's dropped.

Reviewed-by: Alice Ryhl <[email protected]>
Reviewed-by: Benno Lossin <[email protected]>
Reviewed-by: Gary Guo <[email protected]>
Signed-off-by: Danilo Krummrich <[email protected]>
Link: https://lore.kernel.org/r/[email protected]
[ Fixed typos. - Miguel ]
Signed-off-by: Miguel Ojeda <[email protected]>

rust: alloc: implement kernel `Vec` type

`Vec` provides a contiguous growable array type with contents allocated
with the kernel's allocators (e.g. `Kmalloc`, `Vmalloc` or `KVmalloc`).

In contrast to Rust's stdlib `Vec` type, the kernel `Vec` type considers
the kernel's GFP flags for all appropriate functions, always reports
allocation failures through `Result<_, AllocError>` and remains
independent from unstable features.

[ This patch starts using a new unstable feature, `inline_const`, but
  it was stabilized in Rust 1.79.0, i.e. the next version after the
  minimum one, thus it will not be an issue. - Miguel ]

Reviewed-by: Benno Lossin <[email protected]>
Reviewed-by: Gary Guo <[email protected]>
Signed-off-by: Danilo Krummrich <[email protected]>
Link: https://lore.kernel.org/r/[email protected]
[ Cleaned `rustdoc` unescaped backtick warning, added a couple more
  backticks elsewhere, fixed typos, sorted `feature`s, rewrapped
  documentation lines. - Miguel ]
Signed-off-by: Miguel Ojeda <[email protected]>

rust: alloc: introduce `ArrayLayout`

When allocating memory for arrays using allocators, the `Layout::array`
function is typically used. It returns a result, since the given size
might be too big. However, `Vec` and its iterators store their allocated
capacity and thus they already did check that the size is not too big.

The `ArrayLayout` type provides this exact behavior, as it can be
infallibly converted into a `Layout`. Instead of a `usize` capacity,
`Vec` and other similar array-storing types can use `ArrayLayout`
instead.

Reviewed-by: Gary Guo <[email protected]>
Signed-off-by: Benno Lossin <[email protected]>
Signed-off-by: Danilo Krummrich <[email protected]>
Link: https://lore.kernel.org/r/[email protected]
[ Formatted a few comments. - Miguel ]
Signed-off-by: Miguel Ojeda <[email protected]>

rust: alloc: add `Box` to prelude

Now that we removed `BoxExt` and the corresponding includes in
prelude.rs, add the new kernel `Box` type instead.

Reviewed-by: Alice Ryhl <[email protected]>
Reviewed-by: Benno Lossin <[email protected]>
Reviewed-by: Gary Guo <[email protected]>
Signed-off-by: Danilo Krummrich <[email protected]>
Link: https://lore.kernel.org/r/[email protected]
Signed-off-by: Miguel Ojeda <[email protected]>

rust: alloc: remove extension of std's `Box`

Now that all existing `Box` users were moved to the kernel `Box` type,
remove the `BoxExt` extension and all other related extensions.

Reviewed-by: Alice Ryhl <[email protected]>
Reviewed-by: Benno Lossin <[email protected]>
Reviewed-by: Gary Guo <[email protected]>
Signed-off-by: Danilo Krummrich <[email protected]>
Link: https://lore.kernel.org/r/[email protected]
Signed-off-by: Miguel Ojeda <[email protected]>

rust: treewide: switch to our kernel `Box` type

Now that we got the kernel `Box` type in place, convert all existing
`Box` users to make use of it.

Reviewed-by: Alice Ryhl <[email protected]>
Reviewed-by: Benno Lossin <[email protected]>
Reviewed-by: Gary Guo <[email protected]>
Signed-off-by: Danilo Krummrich <[email protected]>
Link: https://lore.kernel.org/r/[email protected]
Signed-off-by: Miguel Ojeda <[email protected]>

rust: alloc: implement kernel `Box`

`Box` provides the simplest way to allocate memory for a generic type
with one of the kernel's allocators, e.g. `Kmalloc`, `Vmalloc` or
`KVmalloc`.

In contrast to Rust's `Box` type, the kernel `Box` type considers the
kernel's GFP flags for all appropriate functions, always reports
allocation failures through `Result<_, AllocError>` and remains
independent from unstable features.

Reviewed-by: Benno Lossin <[email protected]>
Reviewed-by: Gary Guo <[email protected]>
Signed-off-by: Danilo Krummrich <[email protected]>
Link: https://lore.kernel.org/r/[email protected]
[ Added backticks, fixed typos. - Miguel ]
Signed-off-by: Miguel Ojeda <[email protected]>

rust: alloc: add __GFP_NOWARN to `Flags`

Some test cases in subsequent patches provoke allocation failures. Add
`__GFP_NOWARN` to enable test cases to silence unpleasant warnings.

Reviewed-by: Alice Ryhl <[email protected]>
Reviewed-by: Benno Lossin <[email protected]>
Reviewed-by: Gary Guo <[email protected]>
Signed-off-by: Danilo Krummrich <[email protected]>
Link: https://lore.kernel.org/r/[email protected]
Signed-off-by: Miguel Ojeda <[email protected]>

rust: alloc: implement `KVmalloc` allocator

Implement `Allocator` for `KVmalloc`, an `Allocator` that tries to
allocate memory with `kmalloc` first and, on failure, falls back to
`vmalloc`.

All memory allocations made with `KVmalloc` end up in
`kvrealloc_noprof()`; all frees in `kvfree()`.

Reviewed-by: Alice Ryhl <[email protected]>
Reviewed-by: Benno Lossin <[email protected]>
Reviewed-by: Gary Guo <[email protected]>
Signed-off-by: Danilo Krummrich <[email protected]>
Link: https://lore.kernel.org/r/[email protected]
[ Reworded typo. - Miguel ]
Signed-off-by: Miguel Ojeda <[email protected]>

rust: alloc: implement `Vmalloc` allocator

Implement `Allocator` for `Vmalloc`, the kernel's virtually contiguous
allocator, typically used for larger objects, (much) larger than page
size.

All memory allocations made with `Vmalloc` end up in `vrealloc()`.

Reviewed-by: Alice Ryhl <[email protected]>
Reviewed-by: Benno Lossin <[email protected]>
Reviewed-by: Gary Guo <[email protected]>
Signed-off-by: Danilo Krummrich <[email protected]>
Link: https://lore.kernel.org/r/[email protected]
Signed-off-by: Miguel Ojeda <[email protected]>

rust: alloc: add module `allocator_test`

`Allocator`s, such as `Kmalloc`, will be used by e.g. `Box` and `Vec` in
subsequent patches, and hence this dependency propagates throughout the
whole kernel.

Add the `allocator_test` module that provides an empty implementation
for all `Allocator`s in the kernel, such that we don't break the
`rusttest` make target in subsequent patches.

Reviewed-by: Alice Ryhl <[email protected]>
Reviewed-by: Benno Lossin <[email protected]>
Reviewed-by: Gary Guo <[email protected]>
Signed-off-by: Danilo Krummrich <[email protected]>
Link: https://lore.kernel.org/r/[email protected]
[ Added missing `_old_layout` parameter as discussed. - Miguel ]
Signed-off-by: Miguel Ojeda <[email protected]>

rust: alloc: implement `Allocator` for `Kmalloc`

Implement `Allocator` for `Kmalloc`, the kernel's default allocator,
typically used for objects smaller than page size.

All memory allocations made with `Kmalloc` end up in `krealloc()`.

It serves as allocator for the subsequently introduced types `KBox` and
`KVec`.

Reviewed-by: Benno Lossin <[email protected]>
Reviewed-by: Gary Guo <[email protected]>
Signed-off-by: Danilo Krummrich <[email protected]>
Link: https://lore.kernel.org/r/[email protected]
Signed-off-by: Miguel Ojeda <[email protected]>

rust: alloc: make `allocator` module public

Subsequent patches implement allocators such as `Kmalloc`, `Vmalloc`,
`KVmalloc`; we need them to be available outside of the kernel crate as
well.

Reviewed-by: Benno Lossin <[email protected]>
Reviewed-by: Gary Guo <[email protected]>
Signed-off-by: Danilo Krummrich <[email protected]>
Link: https://lore.kernel.org/r/[email protected]
Signed-off-by: Miguel Ojeda <[email protected]>

rust: alloc: implement `ReallocFunc`

`ReallocFunc` is an abstraction for the kernel's realloc derivates, such
as `krealloc`, `vrealloc` and `kvrealloc`.

All of the named functions share the same function signature and
implement the same semantics. The `ReallocFunc` abstractions provides a
generalized wrapper around those, to trivialize the implementation of
`Kmalloc`, `Vmalloc` and `KVmalloc` in subsequent patches.

Reviewed-by: Benno Lossin <[email protected]>
Reviewed-by: Gary Guo <[email protected]>
Signed-off-by: Danilo Krummrich <[email protected]>
Link: https://lore.kernel.org/r/[email protected]
[ Added temporary `allow(dead_code)` for `dangling_from_layout` to clean
  warning in `rusttest` target as discussed in the list (but it is
  needed earlier, i.e. in this patch already). Added colon. - Miguel ]
Signed-off-by: Miguel Ojeda <[email protected]>

rust: alloc: rename `KernelAllocator` to `Kmalloc`

Subsequent patches implement `Vmalloc` and `KVmalloc` allocators, hence
align `KernelAllocator` to this naming scheme.

Reviewed-by: Alice Ryhl <[email protected]>
Reviewed-by: Benno Lossin <[email protected]>
Reviewed-by: Gary Guo <[email protected]>
Signed-off-by: Danilo Krummrich <[email protected]>
Link: https://lore.kernel.org/r/[email protected]
Signed-off-by: Miguel Ojeda <[email protected]>

rust: alloc: separate `aligned_size` from `krealloc_aligned`

Separate `aligned_size` from `krealloc_aligned`.

Subsequent patches implement `Allocator` derivates, such as `Kmalloc`,
that require `aligned_size` and replace the original `krealloc_aligned`.

Reviewed-by: Alice Ryhl <[email protected]>
Reviewed-by: Benno Lossin <[email protected]>
Reviewed-by: Gary Guo <[email protected]>
Signed-off-by: Danilo Krummrich <[email protected]>
Link: https://lore.kernel.org/r/[email protected]
Signed-off-by: Miguel Ojeda <[email protected]>

rust: alloc: add `Allocator` trait

Add a kernel specific `Allocator` trait, that in contrast to the one in
Rust's core library doesn't require unstable features and supports GFP
flags.

Subsequent patches add the following trait implementors: `Kmalloc`,
`Vmalloc` and `KVmalloc`.

Reviewed-by: Alice Ryhl <[email protected]>
Reviewed-by: Benno Lossin <[email protected]>
Reviewed-by: Gary Guo <[email protected]>
Signed-off-by: Danilo Krummrich <[email protected]>
Link: https://lore.kernel.org/r/[email protected]
[ Fixed typo. - Miguel ]
Signed-off-by: Miguel Ojeda <[email protected]>

rust: kernel: move `FromBytes` and `AsBytes` traits to a new `transmute` module

Refactor the `FromBytes` and `AsBytes` traits from `types.rs` into a new
`transmute.rs` module:

 - Add `rust/kernel/transmute.rs` with the definitions of `FromBytes`
   and `AsBytes`.

 - Remove the same trait definitions from `rust/kernel/types.rs`.

 - Update `rust/kernel/uaccess.rs` to import `AsBytes` and `FromBytes`
   from `transmute.rs`.

The traits and their implementations remain unchanged.

Suggested-by: Benno Lossin <[email protected]>
Link: https://github.com/Rust-for-Linux/linux/issues/1117
Signed-off-by: Aliet Exposito Garcia <[email protected]>
Reviewed-by: Fiona Behrens <[email protected]>
Reviewed-by: Benno Lossin <[email protected]>
Link: https://lore.kernel.org/r/[email protected]
[ Rebased on top of the lints series and slightly reworded. - Miguel ]
Signed-off-by: Miguel Ojeda <[email protected]>

rust: error: optimize error type to use nonzero

Optimize `Result<(), Error>` size by changing `Error` type to
`NonZero*` for niche optimization.

This reduces the space used by the `Result` type, as the `NonZero*`
type enables the compiler to apply more efficient memory layout.
For example, the `Result<(), Error>` changes size from 8 to 4 bytes.

Link: https://github.com/Rust-for-Linux/linux/issues/1120
Signed-off-by: Filipe Xavier <[email protected]>
Reviewed-by: Gary Guo <[email protected]>
Reviewed-by: Alice Ryhl <[email protected]>
Reviewed-by: Fiona Behrens <[email protected]>
Link: https://lore.kernel.org/r/BL0PR02MB4914B9B088865CF237731207E9732@BL0PR02MB4914.namprd02.prod.outlook.com
[ Removed unneeded block around `match`, added backticks in panic
  message and added intra-doc link. - Miguel ]
Signed-off-by: Miguel Ojeda <[email protected]>

rust: lock: add trylock method support for lock backend

Add a non-blocking trylock method to lock backend interface, mutex and
spinlock implementations. It includes a C helper for spin_trylock.

Rust Binder will use this method together with the new shrinker
abstractions to avoid deadlocks in the memory shrinker.

Link: https://lore.kernel.org/all/[email protected]
Signed-off-by: Filipe Xavier <[email protected]>
Reviewed-by: Fiona Behrens <[email protected]>
Reviewed-by: Alice Ryhl <[email protected]>
Reviewed-by: Boqun Feng <[email protected]>
Link: https://lore.kernel.org/r/BL0PR02MB4914579914884B5D7473B3D6E96A2@BL0PR02MB4914.namprd02.prod.outlook.com
[ Slightly reworded. - Miguel ]
Signed-off-by: Miguel Ojeda <[email protected]>

rust: std_vendor: update dbg macro from Rust upstream

`dbg!` contains adapted code from Rust upstream. Compare the kernel
code with the Rust upstream one and update missing column numbers in
`dbg!` outputs.

Column numbers are not copied but adjusted for the kernel's examples.

Suggested-by: Miguel Ojeda <[email protected]>
Link: https://github.com/Rust-for-Linux/linux/issues/1124
Signed-off-by: Deepak Thukral <[email protected]>
Link: https://lore.kernel.org/r/[email protected]
[ Fixed typo and slightly reworded. - Miguel ]
Signed-off-by: Miguel Ojeda <[email protected]>

rust: error: make conversion functions public

Change visibility to public of functions in error.rs:
from_err_ptr, from_errno, from_result and to_ptr.
Additionally, remove dead_code annotations.

Link: https://github.com/Rust-for-Linux/linux/issues/1105
Reviewed-by: Alice Ryhl <[email protected]>
Signed-off-by: Filipe Xavier <[email protected]>
Reviewed-by: Benno Lossin <[email protected]>
Reviewed-by: Gary Guo <[email protected]>
Link: https://lore.kernel.org/r/DM4PR14MB7276E6948E67B3B23D8EA847E9652@DM4PR14MB7276.namprd14.prod.outlook.com
Signed-off-by: Miguel Ojeda <[email protected]>

rust: enable arbitrary_self_types and remove `Receiver`

The term "receiver" means that a type can be used as the type of `self`,
and thus enables method call syntax `foo.bar()` instead of
`Foo::bar(foo)`. Stable Rust as of today (1.81) enables a limited
selection of types (primitives and types in std, e.g. `Box` and `Arc`)
to be used as receivers, while custom types cannot.

We want the kernel `Arc` type to have the same functionality as the Rust
std `Arc`, so we use the `Receiver` trait (gated behind `receiver_trait`
unstable feature) to gain the functionality.

The `arbitrary_self_types` RFC [1] (tracking issue [2]) is accepted and
it will allow all types that implement a new `Receiver` trait (different
from today's unstable trait) to be used as receivers. This trait will be
automatically implemented for all `Deref` types, which include our `Arc`
type, so we no longer have to opt-in to be used as receiver. To prepare
us for the change, remove the `Receiver` implementation and the
associated feature. To still allow `Arc` and others to be used as method
receivers, turn on `arbitrary_self_types` feature instead.

This feature gate is introduced in 1.23.0. It used to enable both
`Deref` types and raw pointer types to be used as receivers, but the
latter is now split into a different feature gate in Rust 1.83 nightly.
We do not need receivers on raw pointers so this change would not affect
us and usage of `arbitrary_self_types` feature would work for all Rust
versions that we support (>=1.78).

Cc: Adrian Taylor <[email protected]>
Link: https://github.com/rust-lang/rfcs/pull/3519
Link: https://github.com/rust-lang/rust/issues/44874
Signed-off-by: Gary Guo <[email protected]>
Reviewed-by: Benno Lossin <[email protected]>
Reviewed-by: Alice Ryhl <[email protected]>
Link: https://lore.kernel.org/r/[email protected]
Signed-off-by: Miguel Ojeda <[email protected]>

rust: std_vendor: simplify `{ .. macro! .. }` with inner attributes

It is cleaner to have a single inner attribute rather than needing
several hidden lines to wrap the macro invocations.

Thus simplify them.

Reviewed-by: Vincenzo Palazzo <[email protected]>
Reviewed-by: Alice Ryhl <[email protected]>
Tested-by: Gary Guo <[email protected]>
Reviewed-by: Gary Guo <[email protected]>
Link: https://lore.kernel.org/r/[email protected]
Signed-off-by: Miguel Ojeda <[email protected]>

Documentation: rust: discuss `#[expect(...)]` in the guidelines

Discuss `#[expect(...)]` in the Lints sections of the coding guidelines
document, which is an upcoming feature in Rust 1.81.0, and explain that
it is generally to be preferred over `allow` unless there is a reason
not to use it (e.g. conditional compilation being involved).

Tested-by: Gary Guo <[email protected]>
Reviewed-by: Gary Guo <[email protected]>
Link: https://lore.kernel.org/r/[email protected]
Signed-off-by: Miguel Ojeda <[email protected]>

rust: start using the `#[expect(...)]` attribute

In Rust, it is possible to `allow` particular warnings (diagnostics,
lints) locally, making the compiler ignore instances of a given warning
within a given function, module, block, etc.

It is similar to `#pragma GCC diagnostic push` + `ignored` + `pop` in C:

    #pragma GCC diagnostic push
    #pragma GCC diagnostic ignored "-Wunused-function"
    static void f(void) {}
    #pragma GCC diagnostic pop

But way less verbose:

    #[allow(dead_code)]
    fn f() {}

By that virtue, it makes it possible to comfortably enable more
diagnostics by default (i.e. outside `W=` levels) that may have some
false positives but that are otherwise quite useful to keep enabled to
catch potential mistakes.

The `#[expect(...)]` attribute [1] takes this further, and makes the
compiler warn if the diagnostic was _not_ produced. For instance, the
following will ensure that, when `f()` is called somewhere, we will have
to remove the attribute:

    #[expect(dead_code)]
    fn f() {}

If we do not, we get a warning from the compiler:

    warning: this lint expectation is unfulfilled
     --> x.rs:3:10
      |
    3 | #[expect(dead_code)]
      |          ^^^^^^^^^
      |
      = note: `#[warn(unfulfilled_lint_expectations)]` on by default

This means that `expect`s do not get forgotten when they are not needed.

See the next commit for more details, nuances on its usage and
documentation on the feature.

The attribute requires the `lint_reasons` [2] unstable feature, but it
is becoming stable in 1.81.0 (to be released on 2024-09-05) and it has
already been useful to clean things up in this patch series, finding
cases where the `allow`s should not have been there.

Thus, enable `lint_reasons` and convert some of our `allow`s to `expect`s
where possible.

This feature was also an example of the ongoing collaboration between
Rust and the kernel -- we tested it in the kernel early on and found an
issue that was quickly resolved [3].

Cc: Fridtjof Stoldt <[email protected]>
Cc: Urgau <[email protected]>
Link: https://rust-lang.github.io/rfcs/2383-lint-reasons.html#expect-lint-attribute
Link: https://github.com/rust-lang/rust/issues/54503
Link: https://github.com/rust-lang/rust/issues/114557
Reviewed-by: Alice Ryhl <[email protected]>
Reviewed-by: Trevor Gross <[email protected]>
Tested-by: Gary Guo <[email protected]>
Reviewed-by: Gary Guo <[email protected]>
Link: https://lore.kernel.org/r/[email protected]
Signed-off-by: Miguel Ojeda <[email protected]>

Documentation: rust: add coding guidelines on lints

In the C side, disabling diagnostics locally, i.e. within the source code,
is rare (at least in the kernel). Sometimes warnings are manipulated
via the flags at the translation unit level, but that is about it.

In Rust, it is easier to change locally the "level" of lints
(e.g. allowing them locally). In turn, this means it is easier to
globally enable more lints that may trigger a few false positives here
and there that need to be allowed locally, but that generally can spot
issues or bugs.

Thus document this.

Reviewed-by: Trevor Gross <[email protected]>
Reviewed-by: Alice Ryhl <[email protected]>
Tested-by: Gary Guo <[email protected]>
Reviewed-by: Gary Guo <[email protected]>
Link: https://lore.kernel.org/r/[email protected]
Signed-off-by: Miguel Ojeda <[email protected]>

rust: enable Clippy's `check-private-items`

In Rust 1.76.0, Clippy added the `check-private-items` lint configuration
option. When turned on (the default is off), it makes several lints
check private items as well.

In our case, it affects two lints we have enabled [1]:
`missing_safety_doc` and `unnecessary_safety_doc`.

It also seems to affect the new `too_long_first_doc_paragraph` lint [2],
even though the documentation does not mention it.

Thus allow the few instances remaining we currently hit and enable
the lint.

Link: https://doc.rust-lang.org/nightly/clippy/lint_configuration.html#check-private-items
Link: https://rust-lang.github.io/rust-clippy/master/index.html#/too_long_first_doc_paragraph
Reviewed-by: Trevor Gross <[email protected]>
Reviewed-by: Alice Ryhl <[email protected]>
Tested-by: Gary Guo <[email protected]>
Reviewed-by: Gary Guo <[email protected]>
Link: https://lore.kernel.org/r/[email protected]
Signed-off-by: Miguel Ojeda <[email protected]>

rust: provide proper code documentation titles

Rust 1.82.0's Clippy is introducing [1][2] a new warn-by-default lint,
`too_long_first_doc_paragraph` [3], which is intended to catch titles
of code documentation items that are too long (likely because no title
was provided and the item documentation starts with a paragraph).

This lint does not currently trigger anywhere, but it does detect a couple
cases if checking for private items gets enabled (which we will do in
the next commit):

    error: first doc comment paragraph is too long
      --> rust/kernel/init/__internal.rs:18:1
       |
    18 | / /// This is the module-internal type implementing `PinInit` and `Init`. It is unsafe to create this
    19 | | /// type, since the closure needs to fulfill the same safety requirement as the
    20 | | /// `__pinned_init`/`__init` functions.
       | |_
       |
       = help: for further information visit https://rust-lang.github.io/rust-clippy/master/index.html#too_long_first_doc_paragraph
       = note: `-D clippy::too-long-first-doc-paragraph` implied by `-D warnings`
       = help: to override `-D warnings` add `#[allow(clippy::too_long_first_doc_paragraph)]`

    error: first doc comment paragraph is too long
     --> rust/kernel/sync/arc/std_vendor.rs:3:1
      |
    3 | / //! The contents of this file come from the Rust standard library, hosted in
    4 | | //! the <https://github.com/rust-lang/rust> repository, licensed under
    5 | | //! "Apache-2.0 OR MIT" and adapted for kernel use. For copyright details,
    6 | | //! see <https://github.com/rust-lang/rust/blob/master/COPYRIGHT>.
      | |_
      |
      = help: for further information visit https://rust-lang.github.io/rust-clippy/master/index.html#too_long_first_doc_paragraph

Thus clean those two instances.

In addition, since we have a second `std_vendor.rs` file with a similar
header, do the same there too (even if that one does not trigger the lint,
because it is `doc(hidden)`).

Link: https://github.com/rust-lang/rust/pull/129531
Link: https://github.com/rust-lang/rust-clippy/pull/12993
Link: https://rust-lang.github.io/rust-clippy/master/index.html#/too_long_first_doc_paragraph
Reviewed-by: Trevor Gross <[email protected]>
Reviewed-by: Alice Ryhl <[email protected]>
Tested-by: Gary Guo <[email protected]>
Reviewed-by: Gary Guo <[email protected]>
Link: https://lore.kernel.org/r/[email protected]
Signed-off-by: Miguel Ojeda <[email protected]>

rust: rbtree: fix `SAFETY` comments that should be `# Safety` sections

The tag `SAFETY` is used for safety comments, i.e. `// SAFETY`, while a
`Safety` section is used for safety preconditions in code documentation,
i.e. `/// # Safety`.

Fix the three instances recently added in `rbtree` that Clippy would
have normally caught in a public item, so that we can enable checking
of private items in one of the following commits.

Fixes: 98c14e40e07a ("rust: rbtree: add cursor")
Reviewed-by: Trevor Gross <[email protected]>
Reviewed-by: Alice Ryhl <[email protected]>
Tested-by: Gary Guo <[email protected]>
Reviewed-by: Gary Guo <[email protected]>
Link: https://lore.kernel.org/r/[email protected]
Signed-off-by: Miguel Ojeda <[email protected]>

rust: replace `clippy::dbg_macro` with `disallowed_macros`

Back when we used Rust 1.60.0 (before Rust was merged in the kernel),
we added `-Wclippy::dbg_macro` to the compilation flags. This worked
great with our custom `dbg!` macro (vendored from `std`, but slightly
modified to use the kernel printing facilities).

However, in the very next version, 1.61.0, it stopped working [1] since
the lint started to use a Rust diagnostic item rather than a path to find
the `dbg!` macro [1]. This behavior remains until the current nightly
(1.83.0).

Therefore, currently, the `dbg_macro` is not doing anything, which
explains why we can invoke `dbg!` in samples/rust/rust_print.rs`, as well
as why changing the `#[allow()]`s to `#[expect()]`s in `std_vendor.rs`
doctests does not work since they are not fulfilled.

One possible workaround is using `rustc_attrs` like the standard library
does. However, this is intended to be internal, and we just started
supporting several Rust compiler versions, so it is best to avoid it.

Therefore, instead, use `disallowed_macros`. It is a stable lint and
is more flexible (in that we can provide different macros), although
its diagnostic message(s) are not as nice as the specialized one (yet),
and does not allow to set different lint levels per macro/path [2].

In turn, this requires allowing the (intentional) `dbg!` use in the
sample, as one would have expected.

Finally, in a single case, the `allow` is fixed to be an inner attribute,
since otherwise it was not being applied.

Link: https://github.com/rust-lang/rust-clippy/issues/11303
Link: https://github.com/rust-lang/rust-clippy/issues/11307
Tested-by: Gary Guo <[email protected]>
Reviewed-by: Gary Guo <[email protected]>
Link: https://lore.kernel.org/r/[email protected]
Signed-off-by: Miguel Ojeda <[email protected]>

rust: introduce `.clippy.toml`

Some Clippy lints can be configured/tweaked. We will use these knobs to
our advantage in later commits.

This is done via a configuration file, `.clippy.toml` [1]. The file is
currently unstable. This may be a problem in the future, but we can adapt
as needed. In addition, we proposed adding Clippy to the Rust CI's RFL
job [2], so we should be able to catch issues pre-merge.

Thus introduce the file.

Link: https://doc.rust-lang.org/clippy/configuration.html
Link: https://github.com/rust-lang/rust/pull/128928
Reviewed-by: Alice Ryhl <[email protected]>
Reviewed-by: Trevor Gross <[email protected]>
Tested-by: Gary Guo <[email protected]>
Reviewed-by: Gary Guo <[email protected]>
Link: https://lore.kernel.org/r/[email protected]
Signed-off-by: Miguel Ojeda <[email protected]>

rust: sync: remove unneeded `#[allow(clippy::non_send_fields_in_send_ty)]`

Rust 1.58.0 (before Rust was merged into the kernel) made Clippy's
`non_send_fields_in_send_ty` lint part of the `suspicious` lint group for
a brief window of time [1] until the minor version 1.58.1 got released
a week after, where the lint was moved back to `nursery`.

By that time, we had already upgraded to that Rust version, and thus we
had `allow`ed the lint here for `CondVar`.

Nowadays, Clippy's `non_send_fields_in_send_ty` would still trigger here
if it were enabled.

Moreover, if enabled, `Lock<T, B>` and `Task` would also require an
`allow`. Therefore, it does not seem like someone is actually enabling it
(in, e.g., a custom flags build).

Finally, the lint does not appear to have had major improvements since
then [2].

Thus remove the `allow` since it is unneeded.

Link: https://github.com/rust-lang/rust/blob/master/RELEASES.md#version-1581-2022-01-20
Link: https://github.com/rust-lang/rust-clippy/issues/8045
Reviewed-by: Alice Ryhl <[email protected]>
Reviewed-by: Trevor Gross <[email protected]>
Tested-by: Gary Guo <[email protected]>
Reviewed-by: Gary Guo <[email protected]>
Link: https://lore.kernel.org/r/[email protected]
Signed-off-by: Miguel Ojeda <[email protected]>

rust: init: remove unneeded `#[allow(clippy::disallowed_names)]`

These few cases, unlike others in the same file, did not need the `allow`.

Thus clean them up.

Reviewed-by: Alice Ryhl <[email protected]>
Reviewed-by: Trevor Gross <[email protected]>
Tested-by: Gary Guo <[email protected]>
Reviewed-by: Gary Guo <[email protected]>
Link: https://lore.kernel.org/r/[email protected]
Signed-off-by: Miguel Ojeda <[email protected]>

rust: enable `rustdoc::unescaped_backticks` lint

In Rust 1.71.0, `rustdoc` added the `unescaped_backticks` lint, which
detects what are typically typos in Markdown formatting regarding inline
code [1], e.g. from the Rust standard library:

    /// ... to `deref`/`deref_mut`` must ...

    /// ... use [`from_mut`]`. Specifically, ...

It does not seem to have almost any false positives, from the experience
of enabling it in the Rust standard library [2], which will be checked
starting with Rust 1.82.0. The maintainers also confirmed it is ready
to be used.

Thus enable it.

Link: https://doc.rust-lang.org/rustdoc/lints.html#unescaped_backticks
Link: https://github.com/rust-lang/rust/pull/128307
Reviewed-by: Trevor Gross <[email protected]>
Reviewed-by: Alice Ryhl <[email protected]>
Tested-by: Gary Guo <[email protected]>
Reviewed-by: Gary Guo <[email protected]>
Link: https://lore.kernel.org/r/[email protected]
Signed-off-by: Miguel Ojeda <[email protected]>

rust: enable `clippy::ignored_unit_patterns` lint

In Rust 1.73.0, Clippy introduced the `ignored_unit_patterns` lint [1]:

> Matching with `()` explicitly instead of `_` outlines the fact that
> the pattern contains no data. Also it would detect a type change
> that `_` would ignore.

There is only a single case that requires a change:

    error: matching over `()` is more explicit
       --> rust/kernel/types.rs:176:45
        |
    176 |         ScopeGuard::new_with_data((), move |_| cleanup())
        |                                             ^ help: use `()` instead of `_`: `()`
        |
        = help: for further information visit https://rust-lang.github.io/rust-clippy/master/index.html#ignored_unit_patterns
        = note: requested on the command line with `-D clippy::ignored-unit-patterns`

Thus clean it up and enable the lint -- no functional change intended.

Link: https://rust-lang.github.io/rust-clippy/master/index.html#/ignored_unit_patterns
Reviewed-by: Alice Ryhl <[email protected]>
Reviewed-by: Trevor Gross <[email protected]>
Tested-by: Gary Guo <[email protected]>
Reviewed-by: Gary Guo <[email protected]>
Link: https://lore.kernel.org/r/[email protected]
Signed-off-by: Miguel Ojeda <[email protected]>

rust: enable `clippy::unnecessary_safety_doc` lint

In Rust 1.67.0, Clippy added the `unnecessary_safety_doc` lint [1],
which is similar to `unnecessary_safety_comment`, but for `# Safety`
sections, i.e. safety preconditions in the documentation.

This is something that should not happen with our coding guidelines in
mind. Thus enable the lint to have it machine-checked.

Link: https://rust-lang.github.io/rust-clippy/master/index.html#/unnecessary_safety_doc
Reviewed-by: Trevor Gross <[email protected]>
Reviewed-by: Alice Ryhl <[email protected]>
Tested-by: Gary Guo <[email protected]>
Reviewed-by: Gary Guo <[email protected]>
Link: https://lore.kernel.org/r/[email protected]
Signed-off-by: Miguel Ojeda <[email protected]>

rust: enable `clippy::unnecessary_safety_comment` lint

In Rust 1.67.0, Clippy added the `unnecessary_safety_comment` lint [1],
which is the "inverse" of `undocumented_unsafe_blocks`: it finds places
where safe code has a `// SAFETY` comment attached.

The lint currently finds 3 places where we had such mistakes, thus it
seems already quite useful.

Thus clean those and enable it.

Link: https://rust-lang.github.io/rust-clippy/master/index.html#/unnecessary_safety_comment
Reviewed-by: Alice Ryhl <[email protected]>
Reviewed-by: Trevor Gross <[email protected]>
Reviewed-by: Vincenzo Palazzo <[email protected]>
Tested-by: Gary Guo <[email protected]>
Reviewed-by: Gary Guo <[email protected]>
Link: https://lore.kernel.org/r/[email protected]
Signed-off-by: Miguel Ojeda <[email protected]>

rust: enable `clippy::undocumented_unsafe_blocks` lint

Checking that we are not missing any `// SAFETY` comments in our `unsafe`
blocks is something we have wanted to do for a long time, as well as
cleaning up the remaining cases that were not documented [1].

Back when Rust for Linux started, this was something that could have
been done via a script, like Rust's `tidy`. Soon after, in Rust 1.58.0,
Clippy implemented the `undocumented_unsafe_blocks` lint [2].

Even though the lint has a few false positives, e.g. in some cases where
attributes appear between the comment and the `unsafe` block [3], there
are workarounds and the lint seems quite usable already.

Thus enable the lint now.

We still have a few cases to clean up, so just allow those for the moment
by writing a `TODO` comment -- some of those may be good candidates for
new contributors.

Link: https://github.com/Rust-for-Linux/linux/issues/351
Link: https://rust-lang.github.io/rust-clippy/master/#/undocumented_unsafe_blocks
Link: https://github.com/rust-lang/rust-clippy/issues/13189
Reviewed-by: Alice Ryhl <[email protected]>
Reviewed-by: Trevor Gross <[email protected]>
Tested-by: Gary Guo <[email protected]>
Reviewed-by: Gary Guo <[email protected]>
Link: https://lore.kernel.org/r/[email protected]
Signed-off-by: Miguel Ojeda <[email protected]>

rust: types: avoid repetition in `{As,From}Bytes` impls

In order to provide `// SAFETY` comments for every `unsafe impl`, we would
need to repeat them, which is not very useful and would be harder to read.

We could perhaps allow the lint (ideally within a small module), but we
can take the chance to avoid the repetition of the `impl`s themselves
too by using a small local macro, like in other places where we have
had to do this sort of thing.

Thus add the straightforward `impl_{from,as}bytes!` macros and use them
to implement `FromBytes`.

This, in turn, will allow us in the next patch to place a `// SAFETY`
comment that defers to the actual invocation of the macro.

Reviewed-by: Alice Ryhl <[email protected]>
Reviewed-by: Trevor Gross <[email protected]>
Tested-by: Gary Guo <[email protected]>
Reviewed-by: Gary Guo <[email protected]>
Link: https://lore.kernel.org/r/[email protected]
Signed-off-by: Miguel Ojeda <[email protected]>

rust: sort global Rust flags

Sort the global Rust flags so that it is easier to follow along when we
have more, like this patch series does.

Reviewed-by: Trevor Gross <[email protected]>
Reviewed-by: Alice Ryhl <[email protected]>
Tested-by: Gary Guo <[email protected]>
Reviewed-by: Gary Guo <[email protected]>
Link: https://lore.kernel.org/r/[email protected]
Signed-off-by: Miguel Ojeda <[email protected]>

rust: workqueue: remove unneeded ``#[allow(clippy::new_ret_no_self)]`

Perform the same clean commit b2516f7af9d2 ("rust: kernel: remove
`#[allow(clippy::new_ret_no_self)]`") did for a case that appeared in
workqueue in parallel in commit 7324b88975c5 ("rust: workqueue: add
helper for defining work_struct fields"):

    Clippy triggered a false positive on its `new_ret_no_self` lint
    when using the `pin_init!` macro. Since Rust 1.67.0, that does
    not happen anymore, since Clippy learnt to not warn about
    `-> impl Trait<Self>` [1][2].

    The kernel nowadays uses Rust 1.72.1, thus remove the `#[allow]`.

Link: https://github.com/rust-lang/rust-clippy/issues/7344
Link: https://github.com/rust-lang/rust-clippy/pull/9733
Reviewed-by: Alice Ryhl <[email protected]>
Reviewed-by: Trevor Gross <[email protected]>
Tested-by: Gary Guo <[email protected]>
Reviewed-by: Gary Guo <[email protected]>
Link: https://lore.kernel.org/r/[email protected]
Signed-off-by: Miguel Ojeda <[email protected]>

rust: types: add examples for the `Either` type

We aim to have examples in all Rust types, thus add basic ones for the
`Either` type.

Suggested-by: Miguel Ojeda <[email protected]>
Signed-off-by: Nell Shamrell-Harrington <[email protected]>
Tested-by: Dirk Behme <[email protected]>
Reviewed-by: Trevor Gross <[email protected]>
Reviewed-by: Alice Ryhl <[email protected]>
Link: https://rust-for-linux.zulipchat.com/#narrow/stream/291565/topic/x/near/467478085
Link: https://lore.kernel.org/r/[email protected]
[ Reworded slightly. - Miguel ]
Signed-off-by: Miguel Ojeda <[email protected]>

docs: rust: quick-start: add Ubuntu

Ubuntu has changed their maintenance model for Rust toolchains and is
now providing recent Rust releases in their releases, including both
LTS and non-LTS (interim) releases.

Therefore, add instructions to the Quick Start guide for Ubuntu, like
it is done for the other distributions.

Link: https://packages.ubuntu.com/search?keywords=rustc-1
Link: https://packages.ubuntu.com/search?keywords=bindgen-0
Cc: Zixing Liu <[email protected]>
Cc: William Grant <[email protected]>
Reviewed-by: Kees Cook <[email protected]>
Link: https://lore.kernel.org/r/[email protected]
Signed-off-by: Miguel Ojeda <[email protected]>

Linux 6.12-rc2

Merge tag 'kbuild-fixes-v6.12' of git://git.kernel.org/pub/scm/linux/kernel/git/masahiroy/linux-kbuild

Pull Kbuild fixes from Masahiro Yamada:

 - Move non-boot built-in DTBs to the .rodata section

 - Fix Kconfig bugs

 - Fix maint scripts in the linux-image Debian package

 - Import some list macros to scripts/include/

* tag 'kbuild-fixes-v6.12' of git://git.kernel.org/pub/scm/linux/kernel/git/masahiroy/linux-kbuild:
  kbuild: deb-pkg: Remove blank first line from maint scripts
  kbuild: fix a typo dt_binding_schema -> dt_binding_schemas
  scripts: import more list macros
  kconfig: qconf: fix buffer overflow in debug links
  kconfig: qconf: move conf_read() before drawing tree pain
  kconfig: clear expr::val_is_valid when allocated
  kconfig: fix infinite loop in sym_calc_choice()
  kbuild: move non-boot built-in DTBs to .rodata section

Merge tag 'platform-drivers-x86-v6.12-2' of git://git.kernel.org/pub/scm/linux/kernel/git/pdx86/platform-drivers-x86

Pull x86 platform driver fixes from Hans de Goede:

 - Intel PMC fix for suspend/resume issues on some Sky and Kaby Lake
   laptops

 - Intel Diamond Rapids hw-id additions

 - Documentation and MAINTAINERS fixes

 - Some other small fixes

* tag 'platform-drivers-x86-v6.12-2' of git://git.kernel.org/pub/scm/linux/kernel/git/pdx86/platform-drivers-x86:
  platform/x86: x86-android-tablets: Fix use after free on platform_device_register() errors
  platform/x86: wmi: Update WMI driver API documentation
  platform/x86: dell-ddv: Fix typo in documentation
  platform/x86: dell-sysman: add support for alienware products
  platform/x86/intel: power-domains: Add Diamond Rapids support
  platform/x86: ISST: Add Diamond Rapids to support list
  platform/x86:intel/pmc: Disable ACPI PM Timer disabling on Sky and Kaby Lake
  platform/x86: dell-laptop: Do not fail when encountering unsupported batteries
  MAINTAINERS: Update Intel In Field Scan(IFS) entry
  platform/x86: ISST: Fix the KASAN report slab-out-of-bounds bug

Merge tag 'for-linus' of git://git.kernel.org/pub/scm/virt/kvm/kvm

Pull kvm fixes from Paolo Bonzini:
 "ARM64:

   - Fix pKVM error path on init, making sure we do not change critical
     system registers as we're about to fail

   - Make sure that the host's vector length is at capped by a value
     common to all CPUs

   - Fix kvm_has_feat*() handling of "negative" features, as the current
     code is pretty broken

   - Promote Joey to the status of official reviewer, while James steps
     down -- hopefully only temporarly

  x86:

   - Fix compilation with KVM_INTEL=KVM_AMD=n

   - Fix disabling KVM_X86_QUIRK_SLOT_ZAP_ALL when shadow MMU is in use

  Selftests:

   - Fix compilation on non-x86 architectures"

* tag 'for-linus' of git://git.kernel.org/pub/scm/virt/kvm/kvm:
  x86/reboot: emergency callbacks are now registered by common KVM code
  KVM: x86: leave kvm.ko out of the build if no vendor module is requested
  KVM: x86/mmu: fix KVM_X86_QUIRK_SLOT_ZAP_ALL for shadow MMU
  KVM: arm64: Fix kvm_has_feat*() handling of negative features
  KVM: selftests: Fix build on architectures other than x86_64
  KVM: arm64: Another reviewer reshuffle
  KVM: arm64: Constrain the host to the maximum shared SVE VL with pKVM
  KVM: arm64: Fix __pkvm_init_vcpu cptr_el2 error path

Merge tag 'powerpc-6.12-3' of git://git.kernel.org/pub/scm/linux/kernel/git/powerpc/linux

Pull powerpc fix from Michael Ellerman:

 - Allow r30 to be used in vDSO code generation of getrandom

Thanks to Jason A. Donenfeld

* tag 'powerpc-6.12-3' of git://git.kernel.org/pub/scm/linux/kernel/git/powerpc/linux:
  powerpc/vdso: allow r30 in vDSO code generation of getrandom

kbuild: deb-pkg: Remove blank first line from maint scripts

The blank line causes execve() to fail:

  # strace ./postinst
  execve("./postinst", ...) = -1 ENOEXEC (Exec format error)
  strace: exec: Exec format error
  +++ exited with 1 +++

However running the scripts via shell does work (at least with bash)
because the shell attempts to execute the file as a shell script when
execve() fails.

Fixes: b611daae5efc ("kbuild: deb-pkg: split image and debug objects staging out into functions")
Signed-off-by: Aaron Thompson <[email protected]>
Reviewed-by: Nathan Chancellor <[email protected]>
Reviewed-by: Nicolas Schier <[email protected]>
Signed-off-by: Masahiro Yamada <[email protected]>

kbuild: fix a typo dt_binding_schema -> dt_binding_schemas

If we follow "make help" to "make dt_binding_schema", we will see
below error:

$ make dt_binding_schema
make[1]: *** No rule to make target 'dt_binding_schema'.  Stop.
make: *** [Makefile:224: __sub-make] Error 2

It should be a typo. So this will fix it.

Fixes: 604a57ba9781 ("dt-bindings: kbuild: Add separate target/dependency for processed-schema.json")
Signed-off-by: Xu Yang <[email protected]>
Reviewed-by: Nicolas Schier <[email protected]>
Signed-off-by: Masahiro Yamada <[email protected]>

scripts: import more list macros

Import list_is_first, list_is_last, list_replace, and list_replace_init.

Signed-off-by: Sami Tolvanen <[email protected]>
Signed-off-by: Masahiro Yamada <[email protected]>

platform/x86: x86-android-tablets: Fix use after free on platform_device_register() errors

x86_android_tablet_remove() frees the pdevs[] array, so it should not
be used after calling x86_android_tablet_remove().

When platform_device_register() fails, store the pdevs[x] PTR_ERR() value
into the local ret variable before calling x86_android_tablet_remove()
to avoid using pdevs[] after it has been freed.

Fixes: 5eba0141206e ("platform/x86: x86-android-tablets: Add support for instantiating platform-devs")
Fixes: e2200d3f26da ("platform/x86: x86-android-tablets: Add gpio_keys support to x86_android_tablet_init()")
Cc: [email protected]
Reported-by: Aleksandr Burakov <[email protected]>
Closes: https://lore.kernel.org/platform-driver-x86/[email protected]/
Signed-off-by: Hans de Goede <[email protected]>
Link: https://lore.kernel.org/r/[email protected]

platform/x86: wmi: Update WMI driver API documentation

The WMI driver core now passes the WMI event data to legacy notify
handlers, so WMI devices sharing notification IDs are now being
handled properly.

Fixes: e04e2b760ddb ("platform/x86: wmi: Pass event data directly to legacy notify handlers")
Signed-off-by: Armin Wolf <[email protected]>
Link: https://lore.kernel.org/r/[email protected]
Signed-off-by: Hans de Goede <[email protected]>

platform/x86: dell-ddv: Fix typo in documentation

Fix typo in word 'diagnostics' in documentation.

Signed-off-by: Anaswara T Rajan <[email protected]>
Reviewed-by: Armin Wolf <[email protected]>
Link: https://lore.kernel.org/r/[email protected]
Signed-off-by: Hans de Goede <[email protected]>

platform/x86: dell-sysman: add support for alienware products

Alienware supports firmware-attributes and has its own OEM string.

Signed-off-by: Crag Wang <[email protected]>
Link: https://lore.kernel.org/r/[email protected]
Reviewed-by: Hans de Goede <[email protected]>
Signed-off-by: Hans de Goede <[email protected]>

platform/x86/intel: power-domains: Add Diamond Rapids support

Add Diamond Rapids (INTEL_PANTHERCOVE_X) to tpmi_cpu_ids to support
domaid id mappings.

Signed-off-by: Srinivas Pandruvada <[email protected]>
Link: https://lore.kernel.org/r/[email protected]
Signed-off-by: Hans de Goede <[email protected]>

platform/x86: ISST: Add Diamond Rapids to support list

Add Diamond Rapids (INTEL_PANTHERCOVE_X) to SST support list by adding
to isst_cpu_ids.

Signed-off-by: Srinivas Pandruvada <[email protected]>
Link: https://lore.kernel.org/r/[email protected]
Signed-off-by: Hans de Goede <[email protected]>

platform/x86:intel/pmc: Disable ACPI PM Timer disabling on Sky and Kaby Lake

There have been multiple reports that the ACPI PM Timer disabling is
causing Sky and Kaby Lake systems to hang on all suspend (s2idle, s3,
hibernate) methods.

Remove the acpi_pm_tmr_ctl_offset and acpi_pm_tmr_disable_bit settings from
spt_reg_map to disable the ACPI PM Timer disabling on Sky and Kaby Lake to
fix the hang on suspend.

Fixes: e86c8186d03a ("platform/x86:intel/pmc: Enable the ACPI PM Timer to be turned off when suspended")
Reported-by: Paul Menzel <[email protected]>
Closes: https://lore.kernel.org/linux-pm/[email protected]/
Reported-by: Todd Brandt <[email protected]>
Closes: https://bugzilla.kernel.org/show_bug.cgi?id=219346
Cc: Marek Maslanka <[email protected]>
Signed-off-by: Hans de Goede <[email protected]>
Tested-by: Todd Brandt <[email protected]>
Tested-by: Paul Menzel <[email protected]> # Dell XPS 13 9360/0596KF
Acked-by: Rafael J. Wysocki <[email protected]>
Link: https://lore.kernel.org/r/[email protected]

platform/x86: dell-laptop: Do not fail when encountering unsupported batteries

If the battery hook encounters a unsupported battery, it will
return an error. This in turn will cause the battery driver to
automatically unregister the battery hook.

On machines with multiple batteries however, this will prevent
the battery hook from handling the primary battery, since it will
always get unregistered upon encountering one of the unsupported
batteries.

Fix this by simply ignoring unsupported batteries.

Reviewed-by: Pali Rohár <[email protected]>
Fixes: ab58016c68cc ("platform/x86:dell-laptop: Add knobs to change battery charge settings")
Signed-off-by: Armin Wolf <[email protected]>
Link: https://lore.kernel.org/r/[email protected]
Reviewed-by: Hans de Goede <[email protected]>
Signed-off-by: Hans de Goede <[email protected]>

MAINTAINERS: Update Intel In Field Scan(IFS) entry

Ashok is no longer with Intel and his e-mail address will start bouncing
soon.  Update his email address to the new one he provided to ensure
correct contact details in the MAINTAINERS file.

Signed-off-by: Jithu Joseph <[email protected]>
Link: https://lore.kernel.org/r/[email protected]
Signed-off-by: Hans de Goede <[email protected]>

Merge tag 'kvmarm-fixes-6.12-1' of git://git.kernel.org/pub/scm/linux/kernel/git/kvmarm/kvmarm into HEAD

KVM/arm64 fixes for 6.12, take #1

- Fix pKVM error path on init, making sure we do not change critical
  system registers as we're about to fail

- Make sure that the host's vector length is at capped by a value
  common to all CPUs

- Fix kvm_has_feat*() handling of "negative" features, as the current
  code is pretty broken

- Promote Joey to the status of official reviewer, while James steps
  down -- hopefully only temporarly

x86/reboot: emergency callbacks are now registered by common KVM code

Guard them with CONFIG_KVM_X86_COMMON rather than the two vendor modules.
In practice this has no functional change, because CONFIG_KVM_X86_COMMON
is set if and only if at least one vendor-specific module is being built.
However, it is cleaner to specify CONFIG_KVM_X86_COMMON for functions that
are used in kvm.ko.

Reported-by: Linus Torvalds <[email protected]>
Fixes: 590b09b1d88e ("KVM: x86: Register "emergency disable" callbacks when virt is enabled")
Fixes: 6d55a94222db ("x86/reboot: Unconditionally define cpu_emergency_virt_cb typedef")
Signed-off-by: Paolo Bonzini <[email protected]>

KVM: x86: leave kvm.ko out of the build if no vendor module is requested

kvm.ko is nothing but library code shared by kvm-intel.ko and kvm-amd.ko.
It provides no functionality on its own and it is unnecessary unless one
of the vendor-specific module is compiled.  In particular, /dev/kvm is
not created until one of kvm-intel.ko or kvm-amd.ko is loaded.

Use CONFIG_KVM to decide if it is built-in or a module, but use the
vendor-specific modules for the actual decision on whether to build it.

This also fixes a build failure when CONFIG_KVM_INTEL and CONFIG_KVM_AMD
are both disabled.  The cpu_emergency_register_virt_callback() function
is called from kvm.ko, but it is only defined if at least one of
CONFIG_KVM_INTEL and CONFIG_KVM_AMD is provided.

Fixes: 590b09b1d88e ("KVM: x86: Register "emergency disable" callbacks when virt is enabled")
Signed-off-by: Paolo Bonzini <[email protected]>

Merge tag 'bcachefs-2024-10-05' of git://evilpiepirate.org/bcachefs

Pull bcachefs fixes from Kent Overstreet:
 "A lot of little fixes, bigger ones include:

   - bcachefs's __wait_on_freeing_inode() was broken in rc1 due to vfs
     changes, now fixed along with another lost wakeup

   - fragmentation LRU fixes; fsck now repairs successfully (this is the
     data structure copygc uses); along with some nice simplification.

   - Rework logged op error handling, so that if logged op replay errors
     (due to another filesystem error) we delete the logged op instead
     of going into an infinite loop)

   - Various small filesystem connectivitity repair fixes"

* tag 'bcachefs-2024-10-05' of git://evilpiepirate.org/bcachefs:
  bcachefs: Rework logged op error handling
  bcachefs: Add warn param to subvol_get_snapshot, peek_inode
  bcachefs: Kill snapshot arg to fsck_write_inode()
  bcachefs: Check for unlinked, non-empty dirs in check_inode()
  bcachefs: Check for unlinked inodes with dirents
  bcachefs: Check for directories with no backpointers
  bcachefs: Kill alloc_v4.fragmentation_lru
  bcachefs: minor lru fsck fixes
  bcachefs: Mark more errors AUTOFIX
  bcachefs: Make sure we print error that causes fsck to bail out
  bcachefs: bkey errors are only AUTOFIX during read
  bcachefs: Create lost+found in correct snapshot
  bcachefs: Fix reattach_inode()
  bcachefs: Add missing wakeup to bch2_inode_hash_remove()
  bcachefs: Fix trans_commit disk accounting revert
  bcachefs: Fix bch2_inode_is_open() check
  bcachefs: Fix return type of dirent_points_to_inode_nowarn()
  bcachefs: Fix bad shift in bch2_read_flag_list()

Merge tag 'for-linus-6.12a-rc2-tag' of git://git.kernel.org/pub/scm/linux/kernel/git/xen/tip

Pull xen fix from Juergen Gross:
 "Fix Xen config issue introduced in the merge window"

* tag 'for-linus-6.12a-rc2-tag' of git://git.kernel.org/pub/scm/linux/kernel/git/xen/tip:
  xen: Fix config option reference in XEN_PRIVCMD definition

Merge tag 'ext4_for_linus-5.12-rc2' of git://git.kernel.org/pub/scm/linux/kernel/git/tytso/ext4

Pull ext4 fixes from Ted Ts'o:
 "Fix some ext4 bugs and regressions relating to oneline resize and fast
  commits"

* tag 'ext4_for_linus-5.12-rc2' of git://git.kernel.org/pub/scm/linux/kernel/git/tytso/ext4:
  ext4: fix off by one issue in alloc_flex_gd()
  ext4: mark fc as ineligible using an handle in ext4_xattr_set()
  ext4: use handle to mark fc as ineligible in __track_dentry_update()

Merge tag 'cxl-fixes-6.12-rc2' of git://git.kernel.org/pub/scm/linux/kernel/git/cxl/cxl

Pull cxl fix from Ira Weiny:

 - Fix calculation for SBDF in error injection

* tag 'cxl-fixes-6.12-rc2' of git://git.kernel.org/pub/scm/linux/kernel/git/cxl/cxl:
  EINJ, CXL: Fix CXL device SBDF calculation

Merge tag 'i2c-for-6.12-rc2' of git://git.kernel.org/pub/scm/linux/kernel/git/wsa/linux

Pull i2c fix from Wolfram Sang:

 - Fix potential deadlock during runtime suspend and resume (stm32f7)

* tag 'i2c-for-6.12-rc2' of git://git.kernel.org/pub/scm/linux/kernel/git/wsa/linux:
  i2c: stm32f7: Do not prepare/unprepare clock during runtime suspend/resume

Merge tag 'spi-fix-v6.12-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/broonie/spi

Pull spi fixes from Mark Brown:
 "A small set of driver specific fixes that came in since the merge
  window, about half of which is fixes for correctness in the use of the
  runtime PM APIs done as part of a broader cleanup"

* tag 'spi-fix-v6.12-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/broonie/spi:
  spi: s3c64xx: fix timeout counters in flush_fifo
  spi: atmel-quadspi: Fix wrong register value written to MR
  spi: spi-cadence: Fix missing spi_controller_is_target() check
  spi: spi-cadence: Fix pm_runtime_set_suspended() with runtime pm enabled
  spi: spi-imx: Fix pm_runtime_set_suspended() with runtime pm enabled

Merge tag 'hardening-v6.12-rc2' of git://git.kernel.org/pub/scm/linux/kernel/git/kees/linux

Pull hardening fixes from Kees Cook:

 - gcc plugins: Avoid Kconfig warnings with randstruct (Nathan
   Chancellor)

 - MAINTAINERS: Add security/Kconfig.hardening to hardening section
   (Nathan Chancellor)

 - MAINTAINERS: Add unsafe_memcpy() to the FORTIFY review list

* tag 'hardening-v6.12-rc2' of git://git.kernel.org/pub/scm/linux/kernel/git/kees/linux:
  MAINTAINERS: Add security/Kconfig.hardening to hardening section
  hardening: Adjust dependencies in selection of MODVERSIONS
  MAINTAINERS: Add unsafe_memcpy() to the FORTIFY review list

Merge tag 'lsm-pr-20241004' of git://git.kernel.org/pub/scm/linux/kernel/git/pcmoore/lsm

Pull lsm revert from Paul Moore:
 "Here is the CONFIG_SECURITY_TOMOYO_LKM revert that we've been
  discussing this week. With near unanimous agreement that the original
  TOMOYO patches were not the right way to solve the distro problem
  Tetsuo is trying the solve, reverting is our best option at this time"

* tag 'lsm-pr-20241004' of git://git.kernel.org/pub/scm/linux/kernel/git/pcmoore/lsm:
  tomoyo: revert CONFIG_SECURITY_TOMOYO_LKM support

platform/x86: ISST: Fix the KASAN report slab-out-of-bounds bug

Attaching SST PCI device to VM causes "BUG: KASAN: slab-out-of-bounds".
kasan report:
[   19.411889] ==================================================================
[   19.413702] BUG: KASAN: slab-out-of-bounds in _isst_if_get_pci_dev+0x3d5/0x400 [isst_if_common]
[   19.415634] Read of size 8 at addr ffff888829e65200 by task cpuhp/16/113
[   19.417368]
[   19.418627] CPU: 16 PID: 113 Comm: cpuhp/16 Tainted: G            E      6.9.0 #10
[   19.420435] Hardware name: VMware, Inc. VMware20,1/440BX Desktop Reference Platform, BIOS VMW201.00V.20192059.B64.2207280713 07/28/2022
[   19.422687] Call Trace:
[   19.424091]  <TASK>
[   19.425448]  dump_stack_lvl+0x5d/0x80
[   19.426963]  ? _isst_if_get_pci_dev+0x3d5/0x400 [isst_if_common]
[   19.428694]  print_report+0x19d/0x52e
[   19.430206]  ? __pfx__raw_spin_lock_irqsave+0x10/0x10
[   19.431837]  ? _isst_if_get_pci_dev+0x3d5/0x400 [isst_if_common]
[   19.433539]  kasan_report+0xf0/0x170
[   19.435019]  ? _isst_if_get_pci_dev+0x3d5/0x400 [isst_if_common]
[   19.436709]  _isst_if_get_pci_dev+0x3d5/0x400 [isst_if_common]
[   19.438379]  ? __pfx_sched_clock_cpu+0x10/0x10
[   19.439910]  isst_if_cpu_online+0x406/0x58f [isst_if_common]
[   19.441573]  ? __pfx_isst_if_cpu_online+0x10/0x10 [isst_if_common]
[   19.443263]  ? ttwu_queue_wakelist+0x2c1/0x360
[   19.444797]  cpuhp_invoke_callback+0x221/0xec0
[   19.446337]  cpuhp_thread_fun+0x21b/0x610
[   19.447814]  ? __pfx_cpuhp_thread_fun+0x10/0x10
[   19.449354]  smpboot_thread_fn+0x2e7/0x6e0
[   19.450859]  ? __pfx_smpboot_thread_fn+0x10/0x10
[   19.452405]  kthread+0x29c/0x350
[   19.453817]  ? __pfx_kthread+0x10/0x10
[   19.455253]  ret_from_fork+0x31/0x70
[   19.456685]  ? __pfx_kthread+0x10/0x10
[   19.458114]  ret_from_fork_asm+0x1a/0x30
[   19.459573]  </TASK>
[   19.460853]
[   19.462055] Allocated by task 1198:
[   19.463410]  kasan_save_stack+0x30/0x50
[   19.464788]  kasan_save_track+0x14/0x30
[   19.466139]  __kasan_kmalloc+0xaa/0xb0
[   19.467465]  __kmalloc+0x1cd/0x470
[   19.468748]  isst_if_cdev_register+0x1da/0x350 [isst_if_common]
[   19.470233]  isst_if_mbox_init+0x108/0xff0 [isst_if_mbox_msr]
[   19.471670]  do_one_initcall+0xa4/0x380
[   19.472903]  do_init_module+0x238/0x760
[   19.474105]  load_module+0x5239/0x6f00
[   19.475285]  init_module_from_file+0xd1/0x130
[   19.476506]  idempotent_init_module+0x23b/0x650
[   19.477725]  __x64_sys_finit_module+0xbe/0x130
[   19.476506]  idempotent_init_module+0x23b/0x650
[   19.477725]  __x64_sys_finit_module+0xbe/0x130
[   19.478920]  do_syscall_64+0x82/0x160
[   19.480036]  entry_SYSCALL_64_after_hwframe+0x76/0x7e
[   19.481292]
[   19.482205] The buggy address belongs to the object at ffff888829e65000
 which belongs to the cache kmalloc-512 of size 512
[   19.484818] The buggy address is located 0 bytes to the right of
 allocated 512-byte region [ffff888829e65000, ffff888829e65200)
[   19.487447]
[   19.488328] The buggy address belongs to the physical page:
[   19.489569] page: refcount:1 mapcount:0 mapping:0000000000000000 index:0xffff888829e60c00 pfn:0x829e60
[   19.491140] head: order:3 entire_mapcount:0 nr_pages_mapped:0 pincount:0
[   19.492466] anon flags: 0x57ffffc0000840(slab|head|node=1|zone=2|lastcpupid=0x1fffff)
[   19.493914] page_type: 0xffffffff()
[   19.494988] raw: 0057ffffc0000840 ffff88810004cc80 0000000000000000 0000000000000001
[   19.496451] raw: ffff888829e60c00 0000000080200018 00000001ffffffff 0000000000000000
[   19.497906] head: 0057ffffc0000840 ffff88810004cc80 0000000000000000 0000000000000001
[   19.499379] head: ffff888829e60c00 0000000080200018 00000001ffffffff 0000000000000000
[   19.500844] head: 0057ffffc0000003 ffffea0020a79801 ffffea0020a79848 00000000ffffffff
[   19.502316] head: 0000000800000000 0000000000000000 00000000ffffffff 0000000000000000
[   19.503784] page dumped because: kasan: bad access detected
[   19.505058]
[   19.505970] Memory state around the buggy address:
[   19.507172]  ffff888829e65100: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
[   19.508599]  ffff888829e65180: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
[   19.510013] >ffff888829e65200: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc
[   19.510014]                    ^
[   19.510016]  ffff888829e65280: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc
[   19.510018]  ffff888829e65300: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc
[   19.515367] ==================================================================

The reason for this error is physical_package_ids assigned by VMware VMM
are not continuous and have gaps. This will cause value returned by
topology_physical_package_id() to be more than topology_max_packages().

Here the allocation uses topology_max_packages(). The call to
topology_max_packages() returns maximum logical package ID not physical
ID. Hence use topology_logical_package_id() instead of
topology_physical_package_id().

Fixes: 9a1aac8a96dc ("platform/x86: ISST: PUNIT device mapping with Sub-NUMA clustering")
Cc: [email protected]
Acked-by: Srinivas Pandruvada <[email protected]>
Signed-off-by: Zach Wade <[email protected]>
Link: https://lore.kernel.org/r/[email protected]
Reviewed-by: Hans de Goede <[email protected]>
Signed-off-by: Hans de Goede <[email protected]>

Merge tag 'linux_kselftest-fixes-6.12-rc2' of git://git.kernel.org/pub/scm/linux/kernel/git/shuah/linux-kselftest

Pull kselftest fixes from Shuah Khan:
 "Fixes to build warnings, install scripts, run-time error path, and git
  status cleanups to tests:

   - devices/probe: fix for Python3 regex string syntax warnings

   - clone3: removing unused macro from clone3_cap_checkpoint_restore()

   - vDSO: fix to align getrandom states to cache line

   - core and exec: add missing executables to .gitignore files

   - rtc: change to skip test if /dev/rtc0 can't be accessed

   - timers/posix: fix warn_unused_result result in __fatal_error()

   - breakpoints: fix to detect suspend successful condition correctly

   - hid: fix to install required dependencies to run the test"

* tag 'linux_kselftest-fixes-6.12-rc2' of git://git.kernel.org/pub/scm/linux/kernel/git/shuah/linux-kselftest:
  selftests: breakpoints: use remaining time to check if suspend succeed
  kselftest/devices/probe: Fix SyntaxWarning in regex strings for Python3
  selftest: hid: add missing run-hid-tools-tests.sh
  selftests: vDSO: align getrandom states to cache line
  selftests: exec: update gitignore for load_address
  selftests: core: add unshare_test to gitignore
  clone3: clone3_cap_checkpoint_restore: remove unused MAX_PID_NS_LEVEL macro
  selftests:timers: posix_timers: Fix warn_unused_result in __fatal_error()
  selftest: rtc: Check if could access /dev/rtc0 before testing

bcachefs: Rework logged op error handling

Initially it was thought that we just wanted to ignore errors from
logged op replay, but it turns out we do need to catch -EROFS, or we'll
go into an infinite loop.

Signed-off-by: Kent Overstreet <[email protected]>

bcachefs: Add warn param to subvol_get_snapshot, peek_inode

These shouldn't always be fatal errors - logged op resume, in
particular, and we want it as a parameter there.

Signed-off-by: Kent Overstreet <[email protected]>

bcachefs: Kill snapshot arg to fsck_write_inode()

It was initially believed that it would be better to be explicit about
the snapshot we're updating when writing inodes in fsck; however, it
turns out that passing around the snapshot separately is more error
prone and we're usually updating the inode in the same snapshow we read
it from.

This is different from normal filesystem paths, where we do the update
in the snapshot of the subvolume we're in.

Signed-off-by: Kent Overstreet <[email protected]>

bcachefs: Check for unlinked, non-empty dirs in check_inode()

We want to check for this early so it can be reattached if necessary in
check_unreachable_inodes(); better than letting it be deleted and having
the children reattached, losing their filenames.

Signed-off-by: Kent Overstreet <[email protected]>

bcachefs: Check for unlinked inodes with dirents

link count works differently in bcachefs - it's only nonzero for files
with multiple hardlinks, which means we can also avoid checking it
except for files that are known to have hardlinks.

That means we need a few different checks instead; in particular, we
don't want fsck to delet a file that has a dirent pointing to it.

Signed-off-by: Kent Overstreet <[email protected]>

bcachefs: Check for directories with no backpointers

It's legal for regular files to have missing backpointers (due to
hardlinks), and fsck should automatically add them, but for directories
this is an error that should be flagged.

Signed-off-by: Kent Overstreet <[email protected]>

bcachefs: Kill alloc_v4.fragmentation_lru

The fragmentation_lru field hasn't been needed since we reworked the LRU
btrees to use the btree write buffer; previously it was used to resolve
collisions, but the revised LRU btree uses the backpointer (the bucket)
as part of the key.

It should have been deleted at the time of the LRU rework; since it
wasn't, that left places for bugs to hide, in check/repair.

This fixes LRU fsck on a filesystem image helpfully provided by a user
who disappeared before I could get his name for the reported-by.

Signed-off-by: Kent Overstreet <[email protected]>

bcachefs: minor lru fsck fixes

check_lru_key() wasn't using write buffer updates for deleting bad lru
entries - dating from before the lru btree used the btree write buffer.

And when possibly flushing the btree write buffer (to make sure we're
seeing a real inconsistency), we need to be using the modern
bch2_btree_write_buffer_maybe_flush().

Signed-off-by: Kent Overstreet <[email protected]>

bcachefs: Mark more errors AUTOFIX

Errors are getting marked as AUTOFIX once they've been (re)-tested and
audited.

Signed-off-by: Kent Overstreet <[email protected]>

bcachefs: Make sure we print error that causes fsck to bail out

Signed-off-by: Kent Overstreet <[email protected]>

bcachefs: bkey errors are only AUTOFIX during read

Newly generated keys, in the transaction commit path or write path,
should not be AUTOFIX; those indicate bugs that we need to fail fast
for.

Fixes: 5612daafb764 ("bcachefs: Fix fsck warnings from bkey validation")
Signed-off-by: Kent Overstreet <[email protected]>

bcachefs: Create lost+found in correct snapshot

Signed-off-by: Kent Overstreet <[email protected]>

bcachefs: Fix reattach_inode()

Ensure a copy of the lost+found inode exists in the snapshot that we're
reattaching, so that we don't trigger warnings in
lookup_inode_for_snapshot() later.

Signed-off-by: Kent Overstreet <[email protected]>

bcachefs: Add missing wakeup to bch2_inode_hash_remove()

This fixes two different bugs:

- Looser locking with the rhashtable means we need to recheck if the
  inode is still hashed after prepare_to_wait(), and add a corresponding
  wakeup after removing from the hash table.

- da18ecbf0fb6 ("fs: add i_state helpers") changed the bit waitqueues
  used for inodes, and bcachefs wasn't updated and thus broke; this
  updates bcachefs to the new helper.

Fixes: 112d21fd1a12 ("bcachefs: switch to rhashtable for vfs inodes hash")
Signed-off-by: Kent Overstreet <[email protected]>

ext4: fix off by one issue in alloc_flex_gd()

Wesley reported an issue:

==================================================================
EXT4-fs (dm-5): resizing filesystem from 7168 to 786432 blocks
------------[ cut here ]------------
kernel BUG at fs/ext4/resize.c:324!
CPU: 9 UID: 0 PID: 3576 Comm: resize2fs Not tainted 6.11.0+ #27
RIP: 0010:ext4_resize_fs+0x1212/0x12d0
Call Trace:
 __ext4_ioctl+0x4e0/0x1800
 ext4_ioctl+0x12/0x20
 __x64_sys_ioctl+0x99/0xd0
 x64_sys_call+0x1206/0x20d0
 do_syscall_64+0x72/0x110
 entry_SYSCALL_64_after_hwframe+0x76/0x7e
==================================================================

While reviewing the patch, Honza found that when adjusting resize_bg in
alloc_flex_gd(), it was possible for flex_gd->resize_bg to be bigger than
flexbg_size.

The reproduction of the problem requires the following:

 o_group = flexbg_size * 2 * n;
 o_size = (o_group + 1) * group_size;
 n_group: [o_group + flexbg_size, o_group + flexbg_size * 2)
 o_size = (n_group + 1) * group_size;

Take n=0,flexbg_size=16 as an example:

              last:15
|o---------------|--------------n-|
o_group:0    resize to      n_group:30

The corresponding reproducer is:

img=test.img
rm -f $img
truncate -s 600M $img
mkfs.ext4 -F $img -b 1024 -G 16 8M
dev=`losetup -f --show $img`
mkdir -p /tmp/test
mount $dev /tmp/test
resize2fs $dev 248M

Delete the problematic plus 1 to fix the issue, and add a WARN_ON_ONCE()
to prevent the issue from happening again.

[ Note: another reproucer which this commit fixes is:

  img=test.img
  rm -f $img
  truncate -s 25MiB $img
  mkfs.ext4 -b 4096 -E nodiscard,lazy_itable_init=0,lazy_journal_init=0 $img
  truncate -s 3GiB $img
  dev=`losetup -f --show $img`
  mkdir -p /tmp/test
  mount $dev /tmp/test
  resize2fs $dev 3G
  umount $dev
  losetup -d $dev

  -- TYT ]

Reported-by: Wesley Hershberger <[email protected]>
Closes: https://bugs.launchpad.net/ubuntu/+source/linux/+bug/2081231
Reported-by: Stéphane Graber <[email protected]>
Closes: https://lore.kernel.org/all/[email protected]/
Tested-by: Alexander Mikhalitsyn <[email protected]>
Tested-by: Eric Sandeen <[email protected]>
Fixes: 665d3e0af4d3 ("ext4: reduce unnecessary memory allocation in alloc_flex_gd()")
Cc: [email protected]
Signed-off-by: Baokun Li <[email protected]>
Reviewed-by: Jan Kara <[email protected]>
Link: https://patch.msgid.link/[email protected]
Signed-off-by: Theodore Ts'o <[email protected]>

ext4: mark fc as ineligible using an handle in ext4_xattr_set()

Calling ext4_fc_mark_ineligible() with a NULL handle is racy and may result
in a fast-commit being done before the filesystem is effectively marked as
ineligible.  This patch moves the call to this function so that an handle
can be used.  If a transaction fails to start, then there's not point in
trying to mark the filesystem as ineligible, and an error will eventually be
returned to user-space.

Suggested-by: Jan Kara <[email protected]>
Signed-off-by: Luis Henriques (SUSE) <[email protected]>
Reviewed-by: Jan Kara <[email protected]>
Link: https://patch.msgid.link/[email protected]
Signed-off-by: Theodore Ts'o <[email protected]>
Cc: [email protected]

ext4: use handle to mark fc as ineligible in __track_dentry_update()

Calling ext4_fc_mark_ineligible() with a NULL handle is racy and may result
in a fast-commit being done before the filesystem is effectively marked as
ineligible.  This patch fixes the calls to this function in
__track_dentry_update() by adding an extra parameter to the callback used in
ext4_fc_track_template().

Suggested-by: Jan Kara <[email protected]>
Signed-off-by: Luis Henriques (SUSE) <[email protected]>
Reviewed-by: Jan Kara <[email protected]>
Link: https://patch.msgid.link/[email protected]
Signed-off-by: Theodore Ts'o <[email protected]>
Cc: [email protected]

Merge tag 'arm64-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/arm64/linux

Pull arm64 fixes from Catalin Marinas:
 "A couple of build/config issues and expanding the speculative SSBS
  workaround to more CPUs:

   - Expand the speculative SSBS workaround to cover Cortex-A715,
     Neoverse-N3 and Microsoft Azure Cobalt 100

   - Force position-independent veneers - in some kernel configurations,
     the LLD linker generates position-dependent veneers for otherwise
     position-independent code, resulting in early boot-time failures

   - Fix Kconfig selection of HAVE_DYNAMIC_FTRACE_WITH_ARGS so that it
     is not enabled when not supported by the combination of clang and
     GNU ld"

* tag 'arm64-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/arm64/linux:
  arm64: Subscribe Microsoft Azure Cobalt 100 to erratum 3194386
  arm64: fix selection of HAVE_DYNAMIC_FTRACE_WITH_ARGS
  arm64: errata: Expand speculative SSBS workaround once more
  arm64: cputype: Add Neoverse-N3 definitions
  arm64: Force position-independent veneers

Merge tag 'riscv-for-linus-6.12-rc2' of git://git.kernel.org/pub/scm/linux/kernel/git/riscv/linux

Pull RISC-V fixes from Palmer Dabbelt:

 - PERF_TYPE_BREAKPOINT now returns -EOPNOTSUPP instead of -ENOENT,
   which aligns to other ports and is a saner value

 - The KASAN-related stack size increasing logic has been moved to a C
   header, to avoid dependency issues

* tag 'riscv-for-linus-6.12-rc2' of git://git.kernel.org/pub/scm/linux/kernel/git/riscv/linux:
  riscv: Fix kernel stack size when KASAN is enabled
  drivers/perf: riscv: Align errno for unsupported perf event

Merge tag 'trace-v6.12-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/trace/linux-trace

Pull tracing fixes from Steven Rostedt:

 - Fix tp_printk command line option crashing the kernel

   With the code that can handle a buffer from a previous boot, the
   trace_check_vprintf() needed access to the delta of the address space
   used by the old buffer and the current buffer. To do so, the
   trace_array (tr) parameter was used. But when tp_printk is enabled on
   the kernel command line, no trace buffer is used and the trace event
   is sent directly to printk(). That meant the tr field of the iterator
   descriptor was NULL, and since tp_printk still uses
   trace_check_vprintf() it caused a NULL dereference.

 - Add ptrace.h include to x86 ftrace file for completeness

 - Fix rtla installation when done with out-of-tree build

 - Fix the help messages in rtla that were incorrect

 - Several fixes to fix races with the timerlat and hwlat code

   Several locking issues were discovered with the coordination between
   timerlat kthread creation and hotplug. As timerlat has callbacks from
   hotplug code to start kthreads when CPUs come online. There are also
   locking issues with grabbing the cpu_read_lock() and the locks within
   timerlat.

* tag 'trace-v6.12-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/trace/linux-trace:
  tracing/hwlat: Fix a race during cpuhp processing
  tracing/timerlat: Fix a race during cpuhp processing
  tracing/timerlat: Drop interface_lock in stop_kthread()
  tracing/timerlat: Fix duplicated kthread creation due to CPU online/offline
  x86/ftrace: Include <asm/ptrace.h>
  rtla: Fix the help text in osnoise and timerlat top tools
  tools/rtla: Fix installation from out-of-tree build
  tracing: Fix trace_check_vprintf() when tp_printk is used

Merge tag 'slab-for-6.12-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/vbabka/slab

Pull slab fixes from Vlastimil Babka:
 "Fixes for issues introduced in this merge window: kobject memory leak,
  unsupressed warning and possible lockup in new slub_kunit tests,
  misleading code in kvfree_rcu_queue_batch()"

* tag 'slab-for-6.12-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/vbabka/slab:
  slub/kunit: skip test_kfree_rcu when the slub kunit test is built-in
  mm, slab: suppress warnings in test_leak_destroy kunit test
  rcu/kvfree: Refactor kvfree_rcu_queue_batch()
  mm, slab: fix use of SLAB_SUPPORTS_SYSFS in kmem_cache_release()

Merge tag 'acpi-6.12-rc2' of git://git.kernel.org/pub/scm/linux/kernel/git/rafael/linux-pm

Pull ACPI fixes from Rafael Wysocki:
 "These fix up the ACPI IRQ override quirk list and add two new entries
  to it, add a new quirk to the ACPI backlight (video) driver, and fix
  the ACPI battery driver.

  Specifics:

   - Add a quirk for Dell OptiPlex 5480 AIO to the ACPI backlight
     (video) driver (Hans de Goede)

   - Prevent the ACPI battery driver from crashing when unregistering a
     battery hook and simplify battery hook locking in it (Armin Wolf)

   - Fix up the ACPI IRQ override quirk list and add quirks for Asus
     Vivobook X1704VAP and Asus ExpertBook B2502CVA to it (Hans de
     Goede)"

* tag 'acpi-6.12-rc2' of git://git.kernel.org/pub/scm/linux/kernel/git/rafael/linux-pm:
  ACPI: battery: Fix possible crash when unregistering a battery hook
  ACPI: battery: Simplify battery hook locking
  ACPI: video: Add backlight=native quirk for Dell OptiPlex 5480 AIO
  ACPI: resource: Add Asus ExpertBook B2502CVA to irq1_level_low_skip_override[]
  ACPI: resource: Add Asus Vivobook X1704VAP to irq1_level_low_skip_override[]
  ACPI: resource: Loosen the Asus E1404GAB DMI match to also cover the E1404GA
  ACPI: resource: Remove duplicate Asus E1504GAB IRQ override