Thomas Böhler [Sat, 19 Oct 2024 08:22:51 +0000 (10:22 +0200)]
drm/panic: allow verbose boolean for clarity
Clippy complains about a non-minimal boolean expression with
`nonminimal_bool`:
error: this boolean expression can be simplified
--> drivers/gpu/drm/drm_panic_qr.rs:722:9
|
722 | (x < 8 && y < 8) || (x < 8 && y >= end) || (x >= end && y < 8)
| ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
|
= help: for further information visit https://rust-lang.github.io/rust-clippy/master/index.html#nonminimal_bool
= note: `-D clippy::nonminimal-bool` implied by `-D warnings`
= help: to override `-D warnings` add `#[allow(clippy::nonminimal_bool)]`
help: try
|
722 | !(x >= 8 || y >= 8 && y < end) || (x >= end && y < 8)
| ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
722 | (y >= end || y < 8) && x < 8 || (x >= end && y < 8)
| ~~~~~~~~~~~~~~~~~~~~~~~~~~~~
While this can be useful in a lot of cases, it isn't here because the
line expresses clearly what the intention is. Simplifying the expression
means losing clarity, so opt-out of this lint for the offending line.
Thomas Böhler [Sat, 19 Oct 2024 08:22:50 +0000 (10:22 +0200)]
drm/panic: correctly indent continuation of line in list item
It is common practice in Rust to indent the next line the same amount of
space as the previous one if both belong to the same list item. Clippy
checks for this with the lint `doc_lazy_continuation`.
error: doc list item without indentation
--> drivers/gpu/drm/drm_panic_qr.rs:979:5
|
979 | /// conversion to numeric segments.
| ^
|
= help: if this is supposed to be its own paragraph, add a blank line
= help: for further information visit https://rust-lang.github.io/rust-clippy/master/index.html#doc_lazy_continuation
= note: `-D clippy::doc-lazy-continuation` implied by `-D warnings`
= help: to override `-D warnings` add `#[allow(clippy::doc_lazy_continuation)]`
help: indent this line
|
979 | /// conversion to numeric segments.
| ++
Indent the offending line by 2 more spaces to remove this Clippy error.
Thomas Böhler [Sat, 19 Oct 2024 08:22:49 +0000 (10:22 +0200)]
drm/panic: remove redundant field when assigning value
Rust allows initializing fields of a struct without specifying the
attribute that is assigned if the variable has the same name. In this
instance this is done for all other attributes of the struct except for
`data`. Clippy notes the redundant field name:
error: redundant field names in struct initialization
--> drivers/gpu/drm/drm_panic_qr.rs:495:13
|
495 | data: data,
| ^^^^^^^^^^ help: replace it with: `data`
|
= help: for further information visit https://rust-lang.github.io/rust-clippy/master/index.html#redundant_field_names
= note: `-D clippy::redundant-field-names` implied by `-D warnings`
= help: to override `-D warnings` add `#[allow(clippy::redundant_field_names)]`
Remove the redundant `data` in the assignment to be consistent.
Thomas Böhler [Sat, 19 Oct 2024 08:22:48 +0000 (10:22 +0200)]
drm/panic: prefer eliding lifetimes
Eliding lifetimes when possible instead of specifying them directly is
both shorter and easier to read. Clippy notes this in the
`needless_lifetimes` lint:
error: the following explicit lifetimes could be elided: 'b
--> drivers/gpu/drm/drm_panic_qr.rs:479:16
|
479 | fn new<'a, 'b>(segments: &[&Segment<'b>], data: &'a mut [u8]) -> Option<EncodedMsg<'a>> {
| ^^ ^^
|
= help: for further information visit https://rust-lang.github.io/rust-clippy/master/index.html#needless_lifetimes
= note: `-D clippy::needless-lifetimes` implied by `-D warnings`
= help: to override `-D warnings` add `#[allow(clippy::needless_lifetimes)]`
help: elide the lifetimes
|
479 - fn new<'a, 'b>(segments: &[&Segment<'b>], data: &'a mut [u8]) -> Option<EncodedMsg<'a>> {
479 + fn new<'a>(segments: &[&Segment<'_>], data: &'a mut [u8]) -> Option<EncodedMsg<'a>> {
|
Remove the explicit lifetime annotation in favour of an elided lifetime.
Thomas Böhler [Sat, 19 Oct 2024 08:22:47 +0000 (10:22 +0200)]
drm/panic: remove unnecessary borrow in alignment_pattern
The function `alignment_pattern` returns a static reference to a `u8`
slice. The borrow of the returned element in `ALIGNMENT_PATTERNS` is
already a reference as defined in the array definition above so this
borrow is unnecessary and removed by the compiler. Clippy notes this in
`needless_borrow`:
error: this expression creates a reference which is immediately dereferenced by the compiler
--> drivers/gpu/drm/drm_panic_qr.rs:245:9
|
245 | &ALIGNMENT_PATTERNS[self.0 - 1]
| ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ help: change this to: `ALIGNMENT_PATTERNS[self.0 - 1]`
|
= help: for further information visit https://rust-lang.github.io/rust-clippy/master/index.html#needless_borrow
= note: `-D clippy::needless-borrow` implied by `-D warnings`
= help: to override `-D warnings` add `#[allow(clippy::needless_borrow)]`
Thomas Böhler [Sat, 19 Oct 2024 08:22:46 +0000 (10:22 +0200)]
drm/panic: avoid reimplementing Iterator::find
Rust's standard library's `std::iter::Iterator` trait provides a function
`find` that finds the first element that satisfies a predicate.
The function `Version::from_segments` is doing the same thing but is
implementing the same logic itself.
Clippy complains about this in the `manual_find` lint:
error: manual implementation of `Iterator::find`
--> drivers/gpu/drm/drm_panic_qr.rs:212:9
|
212 | / for v in (1..=40).map(|k| Version(k)) {
213 | | if v.max_data() * 8 >= segments.iter().map(|s| s.total_size_bits(v)).sum() {
214 | | return Some(v);
215 | | }
216 | | }
217 | | None
| |____________^ help: replace with an iterator: `(1..=40).map(|k| Version(k)).find(|&v| v.max_data() * 8 >= segments.iter().map(|s| s.total_size_bits(v)).sum())`
|
= help: for further information visit https://rust-lang.github.io/rust-clippy/master/index.html#manual_find
= note: `-D clippy::manual-find` implied by `-D warnings`
= help: to override `-D warnings` add `#[allow(clippy::manual_find)]`
Use `Iterator::find` instead to make the intention clearer.
At the same time, clean up the redundant closure that Clippy warns
about too:
error: redundant closure
--> drivers/gpu/drm/drm_panic_qr.rs:212:31
|
212 | for v in (1..=40).map(|k| Version(k)) {
| ^^^^^^^^^^^^^^ help: replace the closure with the function itself: `Version`
|
= help: for further information visit https://rust-lang.github.io/rust-clippy/master/index.html#redundant_closure
= note: `-D clippy::redundant-closure` implied by `-D warnings`
= help: to override `-D warnings` add `#[allow(clippy::redundant_closure)]`
MAINTAINERS: add entry for the Rust `alloc` module
Add maintainers entry for the Rust `alloc` module.
Currently, this includes the `Allocator` API itself, `Allocator`
implementations, such as `Kmalloc` or `Vmalloc`, as well as the kernel's
implementation of the primary memory allocation data structures, `Box`
and `Vec`.
kbuild: rust: remove the `alloc` crate and `GlobalAlloc`
Now that we have our own `Allocator`, `Box` and `Vec` types we can remove
Rust's `alloc` crate and the `new_uninit` unstable feature.
Also remove `Kmalloc`'s `GlobalAlloc` implementation -- we can't remove
this in a separate patch, since the `alloc` crate requires a
`#[global_allocator]` to set, that implements `GlobalAlloc`.
rust: alloc: implement `Cmalloc` in module allocator_test
So far the kernel's `Box` and `Vec` types can't be used by userspace
test cases, since all users of those types (e.g. `CString`) use kernel
allocators for instantiation.
In order to allow userspace test cases to make use of such types as
well, implement the `Cmalloc` allocator within the allocator_test module
and type alias all kernel allocators to `Cmalloc`. The `Cmalloc`
allocator uses libc's `realloc()` function as allocator backend.
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.
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.
`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 ]
Benno Lossin [Fri, 4 Oct 2024 15:41:19 +0000 (17:41 +0200)]
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.
`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.
`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.
`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]>
Filipe Xavier [Sat, 5 Oct 2024 19:51:23 +0000 (19:51 +0000)]
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.
Deepak Thukral [Fri, 4 Oct 2024 12:56:16 +0000 (14:56 +0200)]
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.
Gary Guo [Sun, 15 Sep 2024 13:26:31 +0000 (14:26 +0100)]
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).
Miguel Ojeda [Wed, 4 Sep 2024 20:43:46 +0000 (22:43 +0200)]
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).
Miguel Ojeda [Wed, 4 Sep 2024 20:43:45 +0000 (22:43 +0200)]
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:
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].
Miguel Ojeda [Wed, 4 Sep 2024 20:43:44 +0000 (22:43 +0200)]
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.
Miguel Ojeda [Wed, 4 Sep 2024 20:43:43 +0000 (22:43 +0200)]
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.
Miguel Ojeda [Wed, 4 Sep 2024 20:43:42 +0000 (22:43 +0200)]
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)`).
Miguel Ojeda [Wed, 4 Sep 2024 20:43:41 +0000 (22:43 +0200)]
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.
Miguel Ojeda [Wed, 4 Sep 2024 20:43:40 +0000 (22:43 +0200)]
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.
Miguel Ojeda [Wed, 4 Sep 2024 20:43:39 +0000 (22:43 +0200)]
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.
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].
Miguel Ojeda [Wed, 4 Sep 2024 20:43:36 +0000 (22:43 +0200)]
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.
Miguel Ojeda [Wed, 4 Sep 2024 20:43:35 +0000 (22:43 +0200)]
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.
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.
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.
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.
Miguel Ojeda [Wed, 4 Sep 2024 20:43:31 +0000 (22:43 +0200)]
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.
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]`.
Miguel Ojeda [Wed, 25 Sep 2024 14:06:00 +0000 (16:06 +0200)]
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.
Linus Torvalds [Sun, 6 Oct 2024 18:34:55 +0000 (11:34 -0700)]
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
Linus Torvalds [Sun, 6 Oct 2024 18:11:01 +0000 (11:11 -0700)]
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
Linus Torvalds [Sun, 6 Oct 2024 17:53:28 +0000 (10:53 -0700)]
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
Aaron Thompson [Fri, 4 Oct 2024 07:52:45 +0000 (07:52 +0000)]
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]>
Hans de Goede [Sat, 5 Oct 2024 13:05:45 +0000 (15:05 +0200)]
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]
Hans de Goede [Thu, 3 Oct 2024 20:26:13 +0000 (22:26 +0200)]
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.
Armin Wolf [Tue, 1 Oct 2024 21:28:35 +0000 (23:28 +0200)]
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.
Jithu Joseph [Tue, 1 Oct 2024 17:08:08 +0000 (10:08 -0700)]
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.
Paolo Bonzini [Tue, 1 Oct 2024 14:34:58 +0000 (10:34 -0400)]
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]>
Paolo Bonzini [Tue, 1 Oct 2024 14:15:01 +0000 (10:15 -0400)]
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]>
Linus Torvalds [Sat, 5 Oct 2024 22:18:04 +0000 (15:18 -0700)]
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()
Linus Torvalds [Sat, 5 Oct 2024 17:47:00 +0000 (10:47 -0700)]
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()
Linus Torvalds [Sat, 5 Oct 2024 17:31:04 +0000 (10:31 -0700)]
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
Linus Torvalds [Sat, 5 Oct 2024 17:25:04 +0000 (10:25 -0700)]
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
Linus Torvalds [Sat, 5 Oct 2024 17:19:14 +0000 (10:19 -0700)]
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
Linus Torvalds [Sat, 5 Oct 2024 17:10:45 +0000 (10:10 -0700)]
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: 0057ffffc0000840ffff88810004cc8000000000000000000000000000000001
[ 19.496451] raw: ffff888829e60c00000000008020001800000001ffffffff0000000000000000
[ 19.497906] head: 0057ffffc0000840ffff88810004cc8000000000000000000000000000000001
[ 19.499379] head: ffff888829e60c00000000008020001800000001ffffffff0000000000000000
[ 19.500844] head: 0057ffffc0000003ffffea0020a79801ffffea0020a7984800000000ffffffff
[ 19.502316] head: 0000000800000000000000000000000000000000ffffffff0000000000000000
[ 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().
Linus Torvalds [Sat, 5 Oct 2024 00:30:59 +0000 (17:30 -0700)]
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
Kent Overstreet [Tue, 24 Sep 2024 02:06:58 +0000 (22:06 -0400)]
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.
Kent Overstreet [Mon, 30 Sep 2024 04:00:33 +0000 (00:00 -0400)]
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.
Kent Overstreet [Mon, 30 Sep 2024 03:38:37 +0000 (23:38 -0400)]
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.
Kent Overstreet [Mon, 30 Sep 2024 02:38:04 +0000 (22:38 -0400)]
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.
Kent Overstreet [Sat, 28 Sep 2024 19:27:37 +0000 (15:27 -0400)]
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.