Add the ability to track whether a ListArc exists for a given value,
allowing for the creation of ListArcs without going through UniqueArc.

The `impl_list_arc_safe!` macro is extended with a `tracked_by` strategy
that defers the tracking of ListArcs to a field of the struct.
Additionally, the AtomicListArcTracker type is introduced, which can
track whether a ListArc exists using an atomic. By deferring the
tracking to a field of type AtomicListArcTracker, structs gain the
ability to create ListArcs without going through a UniqueArc.

Rust Binder uses this for some objects where we want to be able to
insert them into a linked list at any time. Using the
AtomicListArcTracker, we are able to check whether an item is already in
the list, and if not, we can create a `ListArc` and push it.

The macro has the ability to defer the tracking of ListArcs to a field,
using whatever strategy that field has. Since we don't add any
strategies other than AtomicListArcTracker, another similar option would
be to hard-code that the field should be an AtomicListArcTracker.
However, Rust Binder has a case where the AtomicListArcTracker is not
stored directly in the struct, but in a sub-struct. Furthermore, the
outer struct is generic:

struct Wrapper<T: ?Sized> {
    links: ListLinks,
    inner: T,
}

Here, the Wrapper struct implements ListArcSafe with `tracked_by inner`,
and then the various types used with `inner` also uses the macro to
implement ListArcSafe. Some of them use the untracked strategy, and some
of them use tracked_by with an AtomicListArcTracker. This way, Wrapper
just inherits whichever choice `inner` has made.
Reviewed-by: Benno Lossin <benno.lossin@proton.me>
Signed-off-by: Alice Ryhl <aliceryhl@google.com>
Link: https://lore.kernel.org/r/20240814-linked-list-v5-3-f5f5e8075da0@google.comSigned-off-by: Miguel Ojeda <ojeda@kernel.org>

The `ListArc` type can be thought of as a special reference to a
refcounted object that owns the permission to manipulate the
`next`/`prev` pointers stored in the refcounted object. By ensuring that
each object has only one `ListArc` reference, the owner of that
reference is assured exclusive access to the `next`/`prev` pointers.
When a `ListArc` is inserted into a `List`, the `List` takes ownership
of the `ListArc` reference.

There are various strategies for ensuring that a value has only one
`ListArc` reference. The simplest is to convert a `UniqueArc` into a
`ListArc`. However, the refcounted object could also keep track of
whether a `ListArc` exists using a boolean, which could allow for the
creation of new `ListArc` references from an `Arc` reference. Whatever
strategy is used, the relevant tracking is referred to as "the tracking
inside `T`", and the `ListArcSafe` trait (and its subtraits) are used to
update the tracking when a `ListArc` is created or destroyed.

Note that we allow the case where the tracking inside `T` thinks that a
`ListArc` exists, but actually, there isn't a `ListArc`. However, we do
not allow the opposite situation where a `ListArc` exists, but the
tracking thinks it doesn't. This is because the former can at most
result in us failing to create a `ListArc` when the operation could
succeed, whereas the latter can result in the creation of two `ListArc`
references. Only the latter situation can lead to memory safety issues.

This patch introduces the `impl_list_arc_safe!` macro that allows you to
implement `ListArcSafe` for types using the strategy where a `ListArc`
can only be created from a `UniqueArc`. Other strategies are introduced
in later patches.

This is part of the linked list that Rust Binder will use for many
different things. The strategy where a `ListArc` can only be created
from a `UniqueArc` is actually sufficient for most of the objects that
Rust Binder needs to insert into linked lists. Usually, these are todo
items that are created and then immediately inserted into a queue.

The const generic ID allows objects to have several prev/next pointer
pairs so that the same object can be inserted into several different
lists. You are able to have several `ListArc` references as long as they
correspond to different pointer pairs. The ID itself is purely a
compile-time concept and will not be present in the final binary. Both
the `List` and the `ListArc` will need to agree on the ID for them to
work together. Rust Binder uses this in a few places (e.g. death
recipients) where the same object can be inserted into both generic todo
lists and some other lists for tracking the status of the object.

The ID is a const generic rather than a type parameter because the
`pair_from_unique` method needs to be able to assert that the two ids
are different. There's no easy way to assert that when using types
instead of integers.
Reviewed-by: Benno Lossin <benno.lossin@proton.me>
Signed-off-by: Alice Ryhl <aliceryhl@google.com>
Link: https://lore.kernel.org/r/20240814-linked-list-v5-2-f5f5e8075da0@google.comSigned-off-by: Miguel Ojeda <ojeda@kernel.org>

Add a macro to statically check if a field of a struct is marked with
`#[pin]` ie that it is structurally pinned. This can be used when
`unsafe` code needs to rely on fields being structurally pinned.

The macro has a special "inline" mode for the case where the type
depends on generic parameters from the surrounding scope.
Signed-off-by: Benno Lossin <benno.lossin@proton.me>
Co-developed-by: Alice Ryhl <aliceryhl@google.com>
Signed-off-by: Alice Ryhl <aliceryhl@google.com>
Link: https://lore.kernel.org/r/20240814-linked-list-v5-1-f5f5e8075da0@google.com
[ Replaced `compile_fail` with `ignore` and a TODO note. Removed
  `pub` from example to clean `unreachable_pub` lint. - Miguel ]
Signed-off-by: Miguel Ojeda <ojeda@kernel.org>

Some configuration options such as the supported sanitizer list are
arrays. To support using Rust with sanitizers on x86, we must update the
target.json generator to support this case.

The Push trait is removed in favor of the From trait because the Push
trait doesn't work well in the nested case where you are not really
pushing values to a TargetSpec.
Signed-off-by: Matthew Maurer <mmaurer@google.com>
Signed-off-by: Alice Ryhl <aliceryhl@google.com>
Reviewed-by: Gary Guo <gary@garyguo.net>
Tested-by: Gatlin Newhouse <gatlin.newhouse@gmail.com>
Link: https://lore.kernel.org/r/20240730-target-json-arrays-v1-1-2b376fd0ecf4@google.comSigned-off-by: Miguel Ojeda <ojeda@kernel.org>

Sometimes it is necessary to split allocation and initialization into
two steps. One such situation is when reusing existing allocations
obtained via `Box::drop_contents`. See [1] for an example.

In order to support this use case add `write_[pin_]init` functions to the
pin-init API. These functions operate on already allocated smart
pointers that wrap `MaybeUninit<T>`.

Link: https://lore.kernel.org/rust-for-linux/f026532f-8594-4f18-9aa5-57ad3f5bc592@proton.me/ [1]
Signed-off-by: Benno Lossin <benno.lossin@proton.me>
Reviewed-by: Boqun Feng <boqun.feng@gmail.com>
Reviewed-by: Alice Ryhl <aliceryhl@google.com>
Reviewed-by: Gary Guo <gary@garyguo.net>
Link: https://lore.kernel.org/r/20240819112415.99810-2-benno.lossin@proton.meSigned-off-by: Miguel Ojeda <ojeda@kernel.org>

Sometimes (see [1]) it is necessary to drop the value inside of a
`Box<T>`, but retain the allocation. For example to reuse the allocation
in the future.

Introduce a new function `drop_contents` that turns a `Box<T>` into
`Box<MaybeUninit<T>>` by dropping the value.

Link: https://lore.kernel.org/rust-for-linux/20240418-b4-rbtree-v3-5-323e134390ce@google.com/ [1]
Signed-off-by: Benno Lossin <benno.lossin@proton.me>
Reviewed-by: Boqun Feng <boqun.feng@gmail.com>
Reviewed-by: Alice Ryhl <aliceryhl@google.com>
Link: https://lore.kernel.org/r/20240819112415.99810-1-benno.lossin@proton.meSigned-off-by: Miguel Ojeda <ojeda@kernel.org>

`bindgen` is able to detect certain function attributes and annotate
functions correspondingly in its output for the Rust side, when the
`--enable-function-attribute-detection` is passed.

In particular, it is currently able to use `__must_check` in C
(`#[must_use]` in Rust), which give us a bunch of annotations that are
nice to have to prevent possible issues in Rust abstractions, e.g.:

     extern "C" {
    +    #[must_use]
         pub fn kobject_add(
             kobj: *mut kobject,
             parent: *mut kobject,
             fmt: *const core::ffi::c_char,
             ...
         ) -> core::ffi::c_int;
     }

Apparently, there are edge cases where this can make generation very slow,
which is why it is behind a flag [1], but it does not seem to affect us
in any major way at the moment.

Thus enable it.

Link: https://github.com/rust-lang/rust-bindgen/issues/1465 [1]
Link: https://lore.kernel.org/rust-for-linux/CANiq72=u5Nrz_NW3U3_VqywJkD8pECA07q2pFDd1wjtXOWdkAQ@mail.gmail.com/Reviewed-by: Alice Ryhl <aliceryhl@google.com>
Tested-by: Alice Ryhl <aliceryhl@google.com>
Reviewed-by: Gary Guo <gary@garyguo.net>
Acked-by: Danilo Krummrich <dakr@kernel.org>
Link: https://lore.kernel.org/r/20240814163722.1550064-1-ojeda@kernel.orgSigned-off-by: Miguel Ojeda <ojeda@kernel.org>

The headers in this file are sorted alphabetically, which makes it
easy to quickly resolve conflicts by selecting all of the headers and
invoking :'<,'>sort to sort them. To keep this technique to resolve
conflicts working, also apply sorting to symbols that are not letters.

This file is very prone to merge conflicts, so I think keeping conflict
resolution really easy is more important than not messing with git blame
history.

These includes were originally introduced in commit 3253aba3 ("rust:
block: introduce `kernel::block::mq` module").
Signed-off-by: Alice Ryhl <aliceryhl@google.com>
Acked-by: Danilo Krummrich <dakr@kernel.org>
Link: https://lore.kernel.org/r/20240809132835.274603-1-aliceryhl@google.comSigned-off-by: Miguel Ojeda <ojeda@kernel.org>

This removes the need to explicitly export all symbols.

Generate helper exports similarly to what's currently done for Rust
crates. These helpers are exclusively called from within Rust code and
therefore can be treated similar as other Rust symbols.
Signed-off-by: Gary Guo <gary@garyguo.net>
Reviewed-by: Boqun Feng <boqun.feng@gmail.com>
Tested-by: Boqun Feng <boqun.feng@gmail.com>
Link: https://lore.kernel.org/r/20240817165302.3852499-1-gary@garyguo.net
[ Fixed dependency path, reworded slightly, edited comment a bit and
  rebased on top of the changes made when applying Andreas' patch
  (e.g. no `README.md` anymore, so moved the edits).  - Miguel ]
Signed-off-by: Miguel Ojeda <ojeda@kernel.org>

Now that we should be `objtool`-warning free, enable `objtool` for
Rust too.

Before this patch series, we were already getting warnings under e.g. IBT
builds, since those would see Rust code via `vmlinux.o`.
Tested-by: Alice Ryhl <aliceryhl@google.com>
Tested-by: Benno Lossin <benno.lossin@proton.me>
Reviewed-by: Gary Guo <gary@garyguo.net>
Link: https://lore.kernel.org/r/20240725183325.122827-7-ojeda@kernel.org
[ Solved trivial conflict. - Miguel ]
Signed-off-by: Miguel Ojeda <ojeda@kernel.org>

Rust functions may be `noreturn` (i.e. diverging) by returning the
"never" type, `!`, e.g.

    fn f() -> ! {
        loop {}
    }

Thus list the known `noreturn` functions to avoid such warnings.

Without this, `objtool` would complain if enabled for Rust, e.g.:

    rust/core.o: warning: objtool:
    _R...9panic_fmt() falls through to next function _R...18panic_nounwind_fmt()

    rust/alloc.o: warning: objtool:
    .text: unexpected end of section

In order to do so, we cannot match symbols' names exactly, for two
reasons:

  - Rust mangling scheme [1] contains disambiguators [2] which we
    cannot predict (e.g. they may vary depending on the compiler version).

    One possibility to solve this would be to parse v0 and ignore/zero
    those before comparison.

  - Some of the diverging functions come from `core`, i.e. the Rust
    standard library, which may change with each compiler version
    since they are implementation details (e.g. `panic_internals`).

Thus, to workaround both issues, only part of the symbols are matched,
instead of using the `NORETURN` macro in `noreturns.h`.

Ideally, just like for the C side, we should have a better solution. For
instance, the compiler could give us the list via something like:

    $ rustc --emit=noreturns ...

[ Kees agrees this should be automated and Peter says:

    So it would be fairly simple to make objtool consume a magic section
    emitted by the compiler.. I think we've asked the compiler folks
    for that at some point even, but I don't have clear recollections.

  We will ask upstream Rust about it. And if they agree, then perhaps
  we can get Clang/GCC to implement something similar too -- for this
  sort of thing we can take advantage of the shorter cycles of `rustc`
  as well as their unstable features concept to experiment.

  Gary proposed using DWARF (though it would need to be available), and
  wrote a proof of concept script using the `object` and `gimli` crates:
  https://gist.github.com/nbdd0121/449692570622c2f46a29ad9f47c3379a

    - Miguel ]

Link: https://rust-lang.github.io/rfcs/2603-rust-symbol-name-mangling-v0.html [1]
Link: https://doc.rust-lang.org/rustc/symbol-mangling/v0.html#disambiguator [2]
Acked-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Tested-by: Alice Ryhl <aliceryhl@google.com>
Reviewed-by: Kees Cook <kees@kernel.org>
Tested-by: Benno Lossin <benno.lossin@proton.me>
Link: https://lore.kernel.org/r/20240725183325.122827-6-ojeda@kernel.org
[ Added `len_mismatch_fail` symbol for new `kernel` crate code merged
  since then as well as 3 more `core::panicking` symbols that appear
  in `RUST_DEBUG_ASSERTIONS=y` builds.  - Miguel ]
Signed-off-by: Miguel Ojeda <ojeda@kernel.org>

Support `MITIGATION_SLS` by enabling the target features that Clang does.

Without this, `objtool` would complain if enabled for Rust, e.g.:

    rust/core.o: warning: objtool:
    _R...next_up+0x44: missing int3 after ret

These should be eventually enabled via `-Ctarget-feature` when `rustc`
starts recognizing them (or via a new dedicated flag) [1].

Link: https://github.com/rust-lang/rust/issues/116851 [1]
Reviewed-by: Gary Guo <gary@garyguo.net>
Tested-by: Alice Ryhl <aliceryhl@google.com>
Tested-by: Benno Lossin <benno.lossin@proton.me>
Link: https://lore.kernel.org/r/20240725183325.122827-5-ojeda@kernel.orgSigned-off-by: Miguel Ojeda <ojeda@kernel.org>

The Rust compiler added support for `-Zfunction-return=thunk-extern` [1]
in 1.76.0 [2], i.e. the equivalent of `-mfunction-return=thunk-extern`.
Thus add support for `MITIGATION_RETHUNK`.

Without this, `objtool` would warn if enabled for Rust and already warns
under IBT builds, e.g.:

    samples/rust/rust_print.o: warning: objtool:
    _R...init+0xa5c: 'naked' return found in RETHUNK build

Link: https://github.com/rust-lang/rust/issues/116853 [1]
Link: https://github.com/rust-lang/rust/pull/116892 [2]
Reviewed-by: Gary Guo <gary@garyguo.net>
Tested-by: Alice Ryhl <aliceryhl@google.com>
Tested-by: Benno Lossin <benno.lossin@proton.me>
Reviewed-by: Thomas Gleixner <tglx@linutronix.de>
Link: https://github.com/Rust-for-Linux/linux/issues/945
Link: https://lore.kernel.org/r/20240725183325.122827-4-ojeda@kernel.orgSigned-off-by: Miguel Ojeda <ojeda@kernel.org>

Support `MITIGATION_RETPOLINE` by enabling the target features that
Clang does.

The existing target feature being enabled was a leftover from
our old `rust` branch, and it is not enough: the target feature
`retpoline-external-thunk` only implies `retpoline-indirect-calls`, but
not `retpoline-indirect-branches` (see LLVM's `X86.td`), unlike Clang's
flag of the same name `-mretpoline-external-thunk` which does imply both
(see Clang's `lib/Driver/ToolChains/Arch/X86.cpp`).

Without this, `objtool` would complain if enabled for Rust, e.g.:

    rust/core.o: warning: objtool:
    _R...escape_default+0x13: indirect jump found in RETPOLINE build

In addition, change the comment to note that LLVM is the one disabling
jump tables when retpoline is enabled, thus we do not need to use
`-Zno-jump-tables` for Rust here -- see commit c58f2166ab39 ("Introduce
the "retpoline" x86 mitigation technique ...") [1]:

    The goal is simple: avoid generating code which contains an indirect
    branch that could have its prediction poisoned by an attacker. In
    many cases, the compiler can simply use directed conditional
    branches and a small search tree. LLVM already has support for
    lowering switches in this way and the first step of this patch is
    to disable jump-table lowering of switches and introduce a pass to
    rewrite explicit indirectbr sequences into a switch over integers.

As well as a live example at [2].

These should be eventually enabled via `-Ctarget-feature` when `rustc`
starts recognizing them (or via a new dedicated flag) [3].

Cc: Daniel Borkmann <daniel@iogearbox.net>
Link: https://github.com/llvm/llvm-project/commit/c58f2166ab3987f37cb0d7815b561bff5a20a69a [1]
Link: https://godbolt.org/z/G4YPr58qG [2]
Link: https://github.com/rust-lang/rust/issues/116852 [3]
Reviewed-by: Gary Guo <gary@garyguo.net>
Tested-by: Alice Ryhl <aliceryhl@google.com>
Tested-by: Benno Lossin <benno.lossin@proton.me>
Link: https://github.com/Rust-for-Linux/linux/issues/945
Link: https://lore.kernel.org/r/20240725183325.122827-3-ojeda@kernel.orgSigned-off-by: Miguel Ojeda <ojeda@kernel.org>

Add the equivalent of the `___ADDRESSABLE()` annotation in the
`module_{init,exit}` macros to the Rust `module!` macro.

Without this, `objtool` would complain if enabled for Rust (under IBT
builds), e.g.:

    samples/rust/rust_print.o: warning: objtool: cleanup_module(): not an indirect call target
    samples/rust/rust_print.o: warning: objtool: init_module(): not an indirect call target
Tested-by: Alice Ryhl <aliceryhl@google.com>
Tested-by: Benno Lossin <benno.lossin@proton.me>
Reviewed-by: Gary Guo <gary@garyguo.net>
Link: https://lore.kernel.org/r/20240725183325.122827-2-ojeda@kernel.orgSigned-off-by: Miguel Ojeda <ojeda@kernel.org>

This patch splits up the rust helpers C file. When rebasing patch sets on
upstream linux, merge conflicts in helpers.c is common and time consuming
[1]. Thus, split the file so that each kernel component can live in a
separate file.

This patch lists helper files explicitly and thus conflicts in the file
list is still likely. However, they should be more simple to resolve than
the conflicts usually seen in helpers.c.

[ Removed `README.md` and undeleted the original comment since now,
  in v3 of the series, we have a `helpers.c` again; which also allows
  us to keep the "Sorted alphabetically" line and makes the diff easier.

  In addition, updated the Documentation/ mentions of the file, reworded
  title and removed blank lines at the end of `page.c`.  - Miguel ]

Link: https://rust-for-linux.zulipchat.com/#narrow/stream/288089-General/topic/Splitting.20up.20helpers.2Ec/near/426694012 [1]
Signed-off-by: Andreas Hindborg <a.hindborg@samsung.com>
Reviewed-by: Gary Guo <gary@garyguo.net>
Acked-by: Dirk Behme <dirk.behme@de.bosch.com>
Reviewed-by: Alice Ryhl <aliceryhl@google.com>
Reviewed-by: Benno Lossin <benno.lossin@proton.me>
Link: https://lore.kernel.org/r/20240815103016.2771842-1-nmi@metaspace.dkSigned-off-by: Miguel Ojeda <ojeda@kernel.org>

When enabling Rust in the kernel, we only need to block on the
RANDSTRUCT feature and GCC plugin. The rest of the GCC plugins
are reasonably safe to enable.

[ Originally (years ago) we only had this restriction, but we ended up
  restricting also the rest of the GCC plugins 1) to be on the safe side,
  2) since compiler plugin support could be going away in the kernel and
  3) since mixed builds are best effort so far; so I asked Neal about
  his experience enabling the other plugins -- Neal says:

    When I originally wrote this patch two years ago to get things
    working, Fedora used all the GCC plugins, so I was trying to get GCC +
    Rust to work while minimizing the delta on build differences. This was
    the combination that worked. We've been carrying this patch in the
    Asahi tree for a year now. And while Fedora does not currently have
    GCC plugins enabled because it caused issues with some third-party
    modules (I think it was the NVIDIA driver, but I'm not sure), it was
    around long enough for me to know with some confidence that it was
    fine this way.

  - Miguel ]
Signed-off-by: Neal Gompa <neal@gompa.dev>
Link: https://lore.kernel.org/r/20240731125615.3368813-1-neal@gompa.devSigned-off-by: Miguel Ojeda <ojeda@kernel.org>

For the new Rust support for 32-bit arm [1], Clippy warns:

    error: useless conversion to the same type: `i32`
       --> rust/kernel/error.rs:139:36
        |
    139 |         unsafe { bindings::ERR_PTR(self.0.into()) as *mut _ }
        |                                    ^^^^^^^^^^^^^ help: consider removing `.into()`: `self.0`
        |
        = help: for further information visit https://rust-lang.github.io/rust-clippy/master/index.html#useless_conversion
        = note: `-D clippy::useless-conversion` implied by `-D warnings`
        = help: to override `-D warnings` add `#[allow(clippy::useless_conversion)]`

The `self.0.into()` converts an `c_int` into `ERR_PTR`'s parameter
which is a `c_long`. Thus, both types are `i32` in 32-bit. Therefore,
allow it for those architectures.

Link: https://lore.kernel.org/rust-for-linux/2dbd1491-149d-443c-9802-75786a6a3b73@gmail.com/ [1]
Reviewed-by: Alice Ryhl <aliceryhl@google.com>
Reviewed-by: Christian Schrefl <chrisi.schrefl@gmail.com>
Link: https://lore.kernel.org/r/20240730155702.1110144-1-ojeda@kernel.org
[ Fixed typo in tag. - Miguel ]
Signed-off-by: Miguel Ojeda <ojeda@kernel.org>

There are no guarantees for the pointer returned by `into_foreign`.
This is simply because there is no safety documentation stating any
guarantees. Therefore dereferencing and all other operations for that
pointer are not allowed in a general context (i.e. when the concrete
type implementing the trait is not known).
This might be confusing, therefore add normal documentation to state
that there are no guarantees given for the pointer.
Signed-off-by: Benno Lossin <benno.lossin@proton.me>
Reviewed-by: Alice Ryhl <aliceryhl@google.com>
Link: https://lore.kernel.org/r/20240730182251.1466684-1-benno.lossin@proton.meSigned-off-by: Miguel Ojeda <ojeda@kernel.org>

We already implement ForeignOwnable for Box<T>, but it may be useful to
store pinned data in a ForeignOwnable container. This patch makes that
possible.

This will be used together with upcoming miscdev abstractions, which
Binder will use when binderfs is disabled.
Signed-off-by: Alice Ryhl <aliceryhl@google.com>
Reviewed-by: Benno Lossin <benno.lossin@proton.me>
Link: https://lore.kernel.org/r/20240730-foreign-ownable-pin-box-v1-1-b1d70cdae541@google.comSigned-off-by: Miguel Ojeda <ojeda@kernel.org>

For pinned and unpinned initialization of structs, a trait named
`InPlaceInit` exists for uniform access. `Arc` did not implement
`InPlaceInit` yet, although the functions already existed. The main
reason for that, was that the trait itself returned a `Pin<Self>`. The
`Arc` implementation of the kernel is already implicitly pinned.

To enable `Arc` to implement `InPlaceInit` and to have uniform access,
for in-place and pinned in-place initialization, an associated type is
introduced for `InPlaceInit`. The new implementation of `InPlaceInit`
for `Arc` sets `Arc` as the associated type. Older implementations use
an explicit `Pin<T>` as the associated type. The implemented methods for
`Arc` are mostly moved from a direct implementation on `Arc`. There
should be no user impact. The implementation for `ListArc` is omitted,
because it is not merged yet.

Link: https://github.com/Rust-for-Linux/linux/issues/1079Signed-off-by: Alex Mantel <alexmantel93@mailbox.org>
Reviewed-by: Alice Ryhl <aliceryhl@google.com>
Reviewed-by: Benno Lossin <benno.lossin@proton.me>
Link: https://lore.kernel.org/r/20240727042442.682109-1-alexmantel93@mailbox.org
[ Removed "Rusts" (Benno). - Miguel ]
Signed-off-by: Miguel Ojeda <ojeda@kernel.org>

Merge tag 'driver-core-6.11-rc4' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/driver-core

Pull driver core fixes from Greg KH:
 "Here are two driver fixes for regressions from 6.11-rc1 due to the
  driver core change making a structure in a driver core callback const.

  These were missed by all testing EXCEPT for what Bart happened to be
  running, so I appreciate the fixes provided here for some
  odd/not-often-used driver subsystems that nothing else happened to
  catch.

  Both of these fixes have been in linux-next all week with no reported
  issues"

* tag 'driver-core-6.11-rc4' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/driver-core:
  mips: sgi-ip22: Fix the build
  ARM: riscpc: ecard: Fix the build

Pull char / misc fixes from Greg KH:
 "Here are some small char/misc fixes for 6.11-rc4 to resolve reported
  problems. Included in here are:

   - fastrpc revert of a change that broke userspace

   - xillybus fixes for reported issues

  Half of these have been in linux-next this week with no reported
  problems, I don't know if the last bit of xillybus driver changes made
  it in, but they are 'obviously correct' so will be safe :)"

* tag 'char-misc-6.11-rc4' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/char-misc:
  char: xillybus: Check USB endpoints when probing device
  char: xillybus: Refine workqueue handling
  Revert "misc: fastrpc: Restrict untrusted app to attach to privileged PD"
  char: xillybus: Don't destroy workqueue from work item running on it

Pull tty / serial fixes from Greg KH:
 "Here are some small tty and serial driver fixes for 6.11-rc4 to
  resolve some reported problems. Included in here are:

   - conmakehash.c userspace build issues

   - fsl_lpuart driver fix

   - 8250_omap revert for reported regression

   - atmel_serial rts flag fix

  All of these have been in linux-next this week with no reported
  issues"

* tag 'tty-6.11-rc4' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/tty:
  Revert "serial: 8250_omap: Set the console genpd always on if no console suspend"
  tty: atmel_serial: use the correct RTS flag.
  tty: vt: conmakehash: remove non-portable code printing comment header
  tty: serial: fsl_lpuart: mark last busy before uart_add_one_port

Pull USB / Thunderbolt driver fixes from Greg KH:
 "Here are some small USB and Thunderbolt driver fixes for 6.11-rc4 to
  resolve some reported issues. Included in here are:

   - thunderbolt driver fixes for reported problems

   - typec driver fixes

   - xhci fixes

   - new device id for ljca usb driver

  All of these have been in linux-next this week with no reported
  issues"

* tag 'usb-6.11-rc4' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/usb:
  xhci: Fix Panther point NULL pointer deref at full-speed re-enumeration
  usb: misc: ljca: Add Lunar Lake ljca GPIO HID to ljca_gpio_hids[]
  Revert "usb: typec: tcpm: clear pd_event queue in PORT_RESET"
  usb: typec: ucsi: Fix the return value of ucsi_run_command()
  usb: xhci: fix duplicate stall handling in handle_tx_event()
  usb: xhci: Check for xhci->interrupters being allocated in xhci_mem_clearup()
  thunderbolt: Mark XDomain as unplugged when router is removed
  thunderbolt: Fix memory leaks in {port|retimer}_sb_regs_write()

Pull more btrfs fixes from David Sterba:
 "A more fixes. We got reports that shrinker added in 6.10 still causes
  latency spikes and the fixes don't handle all corner cases. Due to
  summer holidays we're taking a shortcut to disable it for release
  builds and will fix it in the near future.

   - only enable extent map shrinker for DEBUG builds, temporary quick
     fix to avoid latency spikes for regular builds

   - update target inode's ctime on unlink, mandated by POSIX

   - properly take lock to read/update block group's zoned variables

   - add counted_by() annotations"

* tag 'for-6.11-rc3-tag' of git://git.kernel.org/pub/scm/linux/kernel/git/kdave/linux:
  btrfs: only enable extent map shrinker for DEBUG builds
  btrfs: zoned: properly take lock to read/update block group's zoned variables
  btrfs: tree-checker: add dev extent item checks
  btrfs: update target inode's ctime on unlink
  btrfs: send: annotate struct name_cache_entry with __counted_by()

fuse_notify_store(), unlike fuse_do_readpage(), does not enable page
zeroing (because it can be used to change partial page contents).

So fuse_notify_store() must be more careful to fully initialize page
contents (including parts of the page that are beyond end-of-file)
before marking the page uptodate.

The current code can leave beyond-EOF page contents uninitialized, which
makes these uninitialized page contents visible to userspace via mmap().

This is an information leak, but only affects systems which do not
enable init-on-alloc (via CONFIG_INIT_ON_ALLOC_DEFAULT_ON=y or the
corresponding kernel command line parameter).

Link: https://bugs.chromium.org/p/project-zero/issues/detail?id=2574
Cc: stable@kernel.org
Fixes: a1d75f25 ("fuse: add store request")
Signed-off-by: Jann Horn <jannh@google.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

Merge tag 'mm-hotfixes-stable-2024-08-17-19-34' of git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm

Pull misc fixes from Andrew Morton:
 "16 hotfixes. All except one are for MM. 10 of these are cc:stable and
  the others pertain to post-6.10 issues.

  As usual with these merges, singletons and doubletons all over the
  place, no identifiable-by-me theme. Please see the lovingly curated
  changelogs to get the skinny"

* tag 'mm-hotfixes-stable-2024-08-17-19-34' of git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm:
  mm/migrate: fix deadlock in migrate_pages_batch() on large folios
  alloc_tag: mark pages reserved during CMA activation as not tagged
  alloc_tag: introduce clear_page_tag_ref() helper function
  crash: fix riscv64 crash memory reserve dead loop
  selftests: memfd_secret: don't build memfd_secret test on unsupported arches
  mm: fix endless reclaim on machines with unaccepted memory
  selftests/mm: compaction_test: fix off by one in check_compaction()
  mm/numa: no task_numa_fault() call if PMD is changed
  mm/numa: no task_numa_fault() call if PTE is changed
  mm/vmalloc: fix page mapping if vm_area_alloc_pages() with high order fallback to order 0
  mm/memory-failure: use raw_spinlock_t in struct memory_failure_cpu
  mm: don't account memmap per-node
  mm: add system wide stats items category
  mm: don't account memmap on failure
  mm/hugetlb: fix hugetlb vs. core-mm PT locking
  mseal: fix is_madv_discard()

Pull powerpc fixes from Michael Ellerman:

 - Fix crashes on 85xx with some configs since the recent hugepd rework.

 - Fix boot warning with hugepages and CONFIG_DEBUG_VIRTUAL on some
   platforms.

 - Don't enable offline cores when changing SMT modes, to match existing
   userspace behaviour.

Thanks to Christophe Leroy, Dr. David Alan Gilbert, Guenter Roeck, Nysal
Jan K.A, Shrikanth Hegde, Thomas Gleixner, and Tyrel Datwyler.

* tag 'powerpc-6.11-2' of git://git.kernel.org/pub/scm/linux/kernel/git/powerpc/linux:
  powerpc/topology: Check if a core is online
  cpu/SMT: Enable SMT only if a core is online
  powerpc/mm: Fix boot warning with hugepages and CONFIG_DEBUG_VIRTUAL
  powerpc/mm: Fix size of allocated PGDIR
  soc: fsl: qbman: remove unused struct 'cgr_comp'

Pull smb client fixes from Steve French:

 - fix for clang warning - additional null check

 - fix for cached write with posix locks

 - flexible structure fix

* tag 'v6.11-rc3-smb3-client-fixes' of git://git.samba.org/sfrench/cifs-2.6:
  smb: smb2pdu.h: Use static_assert() to check struct sizes
  smb3: fix lock breakage for cached writes
  smb/client: avoid possible NULL dereference in cifs_free_subrequest()

Pull i2c fixes from Wolfram Sang:
 "I2C core fix replacing IS_ENABLED() with IS_REACHABLE()

  For host drivers, there are two fixes:

   - Tegra I2C Controller: Addresses a potential double-locking issue
     during probe. ACPI devices are not IRQ-safe when invoking runtime
     suspend and resume functions, so the irq_safe flag should not be
     set.

   - Qualcomm GENI I2C Controller: Fixes an oversight in the exit path
     of the runtime_resume() function, which was missed in the previous
     release"

* tag 'i2c-for-6.11-rc4' of git://git.kernel.org/pub/scm/linux/kernel/git/wsa/linux:
  i2c: tegra: Do not mark ACPI devices as irq safe
  i2c: Use IS_REACHABLE() for substituting empty ACPI functions
  i2c: qcom-geni: Add missing geni_icc_disable in geni_i2c_runtime_resume

Pull SCSI fixes from James Bottomley:
 "Two small fixes to the mpi3mr driver. One to avoid oversize
  allocations in tracing and the other to fix an uninitialized spinlock
  in the user to driver feature request code (used to trigger dumps and
  the like)"

* tag 'scsi-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/jejb/scsi:
  scsi: mpi3mr: Avoid MAX_PAGE_ORDER WARNING for buffer allocations
  scsi: mpi3mr: Add missing spin_lock_init() for mrioc->trigger_lock

Pull xfs fixes from Chandan Babu:

 - Check for presence of only 'attr' feature before scrubbing an inode's
   attribute fork.

 - Restore the behaviour of setting AIL thread to TASK_INTERRUPTIBLE for
   long (i.e. 50ms) sleep durations to prevent high load averages.

 - Do not allow users to change the realtime flag of a file unless the
   datadev and rtdev both support fsdax access modes.

* tag 'xfs-6.11-fixes-3' of git://git.kernel.org/pub/scm/fs/xfs/xfs-linux:
  xfs: conditionally allow FS_XFLAG_REALTIME changes if S_DAX is set
  xfs: revert AIL TASK_KILLABLE threshold
  xfs: attr forks require attr, not attr2

Pull bcachefs fixes from Kent OverstreetL

 - New on disk format version, bcachefs_metadata_version_disk_accounting_inum

   This adds one more disk accounting counter, which counts disk usage
   and number of extents per inode number. This lets us track
   fragmentation, for implementing defragmentation later, and it also
   counts disk usage per inode in all snapshots, which will be a useful
   thing to expose to users.

 - One performance issue we've observed is threads spinning when they
   should be waiting for dirty keys in the key cache to be flushed by
   journal reclaim, so we now have hysteresis for the waiting thread, as
   well as improving the tracepoint and a new time_stat, for tracking
   time blocked waiting on key cache flushing.

... and various assorted smaller fixes.

* tag 'bcachefs-2024-08-16' of git://evilpiepirate.org/bcachefs:
  bcachefs: Fix locking in __bch2_trans_mark_dev_sb()
  bcachefs: fix incorrect i_state usage
  bcachefs: avoid overflowing LRU_TIME_BITS for cached data lru
  bcachefs: Fix forgetting to pass trans to fsck_err()
  bcachefs: Increase size of cuckoo hash table on too many rehashes
  bcachefs: bcachefs_metadata_version_disk_accounting_inum
  bcachefs: Kill __bch2_accounting_mem_mod()
  bcachefs: Make bkey_fsck_err() a wrapper around fsck_err()
  bcachefs: Fix warning in __bch2_fsck_err() for trans not passed in
  bcachefs: Add a time_stat for blocked on key cache flush
  bcachefs: Improve trans_blocked_journal_reclaim tracepoint
  bcachefs: Add hysteresis to waiting on btree key cache flush
  lib/generic-radix-tree.c: Fix rare race in __genradix_ptr_alloc()
  bcachefs: Convert for_each_btree_node() to lockrestart_do()
  bcachefs: Add missing downgrade table entry
  bcachefs: disk accounting: ignore unknown types
  bcachefs: bch2_accounting_invalid() fixup
  bcachefs: Fix bch2_trigger_alloc when upgrading from old versions
  bcachefs: delete faulty fastpath in bch2_btree_path_traverse_cached()

We run this in full RW mode now, so we have to guard against the
superblock buffer being reallocated.
Signed-off-by: Kent Overstreet <kent.overstreet@linux.dev>

Pull memcg-v1 fix from Al Viro:
 "memcg_write_event_control() oops fix"

* tag 'pull-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs:
  memcg_write_event_control(): fix a user-triggerable oops

Pull arm64 fixes from Catalin Marinas:

 - Fix the arm64 __get_mem_asm() to use the _ASM_EXTABLE_##type##ACCESS()
   macro instead of the *_ERR() one in order to avoid writing -EFAULT to
   the value register in case of a fault

 - Initialise all elements of the acpi_early_node_map[] to NUMA_NO_NODE.
   Prior to this fix, only the first element was initialised

 - Move the KASAN random tag seed initialisation after the per-CPU areas
   have been initialised (prng_state is __percpu)

* tag 'arm64-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/arm64/linux:
  arm64: Fix KASAN random tag seed initialization
  arm64: ACPI: NUMA: initialize all values of acpi_early_node_map to NUMA_NO_NODE
  arm64: uaccess: correct thinko in __get_mem_asm()

Pull clk fix from Stephen Boyd:
 "One fix for the new T-Head TH1520 clk driver that marks a bus clk
  critical so that it isn't turned off during late init which breaks
  emmc-sdio"

* tag 'clk-fixes-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/clk/linux:
  clk: thead: fix dependency on clk_ignore_unused

Pull block fixes from Jens Axboe:

 - Fix corruption issues with s390/dasd (Eric, Stefan)

 - Fix a misuse of non irq locking grab of a lock (Li)

 - MD pull request with a single data corruption fix for raid1 (Yu)

* tag 'block-6.11-20240824' of git://git.kernel.dk/linux:
  block: Fix lockdep warning in blk_mq_mark_tag_wait
  md/raid1: Fix data corruption for degraded array with slow disk
  s390/dasd: fix error recovery leading to data corruption on ESE devices
  s390/dasd: Remove DMA alignment