Merge tag 'riscv-mw1-6.15-rc1' of ssh://gitolite.kernel.org/pub/scm/linux/kernel/git/alexghiti/linux into for-next

riscv patches for 6.15-rc1

* A bunch of fixes:
  - We were missing a secondary mmu notifier call when flushing the tlb which is required for IOMMU
  - Fix ftrace panics by saving the registers as expected by ftrace
  - Fix a couple of stimecmp usage related to cpu hotplug
  - Fix a bunch of issues in the misaligned probing handling

* Perf improvements:
  - Introduce support for runtime constant improving perf of d_hash()
  - Add support for huge pfnmaps to improve tlb utilization
  - Use Zawrs to improve smp_cond_load8/16() used by the queued spinlocks

* Hwprobe additions:
  - Add support for Zicntr and Zihpm
  - Add support for Zaamo and Zalrsc
  - Add support for bfloat16 extensiosn
  - Add support for Zicbom (only enabling clean and flush, not inval for security reasons)

* Misc:
  - Add a kernel parameter to bypass the misaligned speed probing since we can't rely on Zicclsm

* tag 'riscv-mw1-6.15-rc1' of ssh://gitolite.kernel.org/pub/scm/linux/kernel/git/alexghiti/linux: (1585 commits)
  riscv: Add runtime constant support
  riscv: Move nop definition to insn-def.h
  Documentation/kernel-parameters: Add riscv unaligned speed parameters
  riscv: Add parameter for skipping access speed tests
  riscv: Fix set up of vector cpu hotplug callback
  riscv: Fix set up of cpu hotplug callbacks
  riscv: Change check_unaligned_access_speed_all_cpus to void
  riscv: Fix check_unaligned_access_all_cpus
  riscv: Fix riscv_online_cpu_vec
  riscv: Annotate unaligned access init functions
  KVM: riscv: selftests: Add Zaamo/Zalrsc extensions to get-reg-list test
  RISC-V: KVM: Allow Zaamo/Zalrsc extensions for Guest/VM
  riscv: hwprobe: export Zaamo and Zalrsc extensions
  riscv: add parsing for Zaamo and Zalrsc extensions
  dt-bindings: riscv: add Zaamo and Zalrsc ISA extension description
  riscv: fgraph: Fix stack layout to match __arch_ftrace_regs argument of ftrace_return_to_handler
  riscv: fgraph: Select HAVE_FUNCTION_GRAPH_TRACER depends on HAVE_DYNAMIC_FTRACE_WITH_ARGS
  riscv: Fix missing __free_pages() in check_vector_unaligned_access()
  riscv: Fix the __riscv_copy_vec_words_unaligned implementation
  riscv: mm: Don't use %pK through printk
  ...

11 files changed, 112 insertions, 37 deletions

diff --git a/rust/kernel/alloc/allocator_test.rs b/rust/kernel/alloc/allocator_test.rs
index e3240d16040b..c37d4c0c64e9 100644
--- a/rust/kernel/alloc/allocator_test.rs
+++ b/rust/kernel/alloc/allocator_test.rs
@@ -62,6 +62,24 @@ unsafe impl Allocator for Cmalloc {
             ));
         }
 
+        // ISO C (ISO/IEC 9899:2011) defines `aligned_alloc`:
+        //
+        // > The value of alignment shall be a valid alignment supported by the implementation
+        // [...].
+        //
+        // As an example of the "supported by the implementation" requirement, POSIX.1-2001 (IEEE
+        // 1003.1-2001) defines `posix_memalign`:
+        //
+        // > The value of alignment shall be a power of two multiple of sizeof (void *).
+        //
+        // and POSIX-based implementations of `aligned_alloc` inherit this requirement. At the time
+        // of writing, this is known to be the case on macOS (but not in glibc).
+        //
+        // Satisfy the stricter requirement to avoid spurious test failures on some platforms.
+        let min_align = core::mem::size_of::<*const crate::ffi::c_void>();
+        let layout = layout.align_to(min_align).map_err(|_| AllocError)?;
+        let layout = layout.pad_to_align();
+
         // SAFETY: Returns either NULL or a pointer to a memory allocation that satisfies or
         // exceeds the given size and alignment requirements.
         let dst = unsafe { libc_aligned_alloc(layout.align(), layout.size()) } as *mut u8;
diff --git a/rust/kernel/error.rs b/rust/kernel/error.rs
index f6ecf09cb65f..a194d83e6835 100644
--- a/rust/kernel/error.rs
+++ b/rust/kernel/error.rs
@@ -107,7 +107,7 @@ impl Error {
         } else {
             // TODO: Make it a `WARN_ONCE` once available.
             crate::pr_warn!(
-                "attempted to create `Error` with out of range `errno`: {}",
+                "attempted to create `Error` with out of range `errno`: {}\n",
                 errno
             );
             code::EINVAL
diff --git a/rust/kernel/faux.rs b/rust/kernel/faux.rs
new file mode 100644
index 000000000000..5acc0c02d451
--- /dev/null
+++ b/rust/kernel/faux.rs
@@ -0,0 +1,67 @@
+// SPDX-License-Identifier: GPL-2.0-only
+
+//! Abstractions for the faux bus.
+//!
+//! This module provides bindings for working with faux devices in kernel modules.
+//!
+//! C header: [`include/linux/device/faux.h`]
+
+use crate::{bindings, device, error::code::*, prelude::*};
+use core::ptr::{addr_of_mut, null, null_mut, NonNull};
+
+/// The registration of a faux device.
+///
+/// This type represents the registration of a [`struct faux_device`]. When an instance of this type
+/// is dropped, its respective faux device will be unregistered from the system.
+///
+/// # Invariants
+///
+/// `self.0` always holds a valid pointer to an initialized and registered [`struct faux_device`].
+///
+/// [`struct faux_device`]: srctree/include/linux/device/faux.h
+#[repr(transparent)]
+pub struct Registration(NonNull<bindings::faux_device>);
+
+impl Registration {
+    /// Create and register a new faux device with the given name.
+    pub fn new(name: &CStr) -> Result<Self> {
+        // SAFETY:
+        // - `name` is copied by this function into its own storage
+        // - `faux_ops` is safe to leave NULL according to the C API
+        let dev = unsafe { bindings::faux_device_create(name.as_char_ptr(), null_mut(), null()) };
+
+        // The above function will return either a valid device, or NULL on failure
+        // INVARIANT: The device will remain registered until faux_device_destroy() is called, which
+        // happens in our Drop implementation.
+        Ok(Self(NonNull::new(dev).ok_or(ENODEV)?))
+    }
+
+    fn as_raw(&self) -> *mut bindings::faux_device {
+        self.0.as_ptr()
+    }
+}
+
+impl AsRef<device::Device> for Registration {
+    fn as_ref(&self) -> &device::Device {
+        // SAFETY: The underlying `device` in `faux_device` is guaranteed by the C API to be
+        // a valid initialized `device`.
+        unsafe { device::Device::as_ref(addr_of_mut!((*self.as_raw()).dev)) }
+    }
+}
+
+impl Drop for Registration {
+    fn drop(&mut self) {
+        // SAFETY: `self.0` is a valid registered faux_device via our type invariants.
+        unsafe { bindings::faux_device_destroy(self.as_raw()) }
+    }
+}
+
+// SAFETY: The faux device API is thread-safe as guaranteed by the device core, as long as
+// faux_device_destroy() is guaranteed to only be called once - which is guaranteed by our type not
+// having Copy/Clone.
+unsafe impl Send for Registration {}
+
+// SAFETY: The faux device API is thread-safe as guaranteed by the device core, as long as
+// faux_device_destroy() is guaranteed to only be called once - which is guaranteed by our type not
+// having Copy/Clone.
+unsafe impl Sync for Registration {}
diff --git a/rust/kernel/init.rs b/rust/kernel/init.rs
index 3f9236c1c9d5..e25d047f3c82 100644
--- a/rust/kernel/init.rs
+++ b/rust/kernel/init.rs
@@ -259,7 +259,7 @@ pub mod macros;
 ///     },
 /// }));
 /// let foo: Pin<&mut Foo> = foo;
-/// pr_info!("a: {}", &*foo.a.lock());
+/// pr_info!("a: {}\n", &*foo.a.lock());
 /// ```
 ///
 /// # Syntax
@@ -319,7 +319,7 @@ macro_rules! stack_pin_init {
 ///     }, GFP_KERNEL)?,
 /// }));
 /// let foo = foo.unwrap();
-/// pr_info!("a: {}", &*foo.a.lock());
+/// pr_info!("a: {}\n", &*foo.a.lock());
 /// ```
 ///
 /// ```rust,ignore
@@ -352,7 +352,7 @@ macro_rules! stack_pin_init {
 ///         x: 64,
 ///     }, GFP_KERNEL)?,
 /// }));
-/// pr_info!("a: {}", &*foo.a.lock());
+/// pr_info!("a: {}\n", &*foo.a.lock());
 /// # Ok::<_, AllocError>(())
 /// ```
 ///
@@ -870,7 +870,7 @@ pub unsafe trait PinInit<T: ?Sized, E = Infallible>: Sized {
     /// use kernel::{types::Opaque, init::pin_init_from_closure};
     /// #[repr(C)]
     /// struct RawFoo([u8; 16]);
-    /// extern {
+    /// extern "C" {
     ///     fn init_foo(_: *mut RawFoo);
     /// }
     ///
@@ -882,7 +882,7 @@ pub unsafe trait PinInit<T: ?Sized, E = Infallible>: Sized {
     ///
     /// impl Foo {
     ///     fn setup(self: Pin<&mut Self>) {
-    ///         pr_info!("Setting up foo");
+    ///         pr_info!("Setting up foo\n");
     ///     }
     /// }
     ///
@@ -986,7 +986,7 @@ pub unsafe trait Init<T: ?Sized, E = Infallible>: PinInit<T, E> {
     ///
     /// impl Foo {
     ///     fn setup(&mut self) {
-    ///         pr_info!("Setting up foo");
+    ///         pr_info!("Setting up foo\n");
     ///     }
     /// }
     ///
@@ -1336,7 +1336,7 @@ impl<T> InPlaceWrite<T> for UniqueArc<MaybeUninit<T>> {
 /// #[pinned_drop]
 /// impl PinnedDrop for Foo {
 ///     fn drop(self: Pin<&mut Self>) {
-///         pr_info!("Foo is being dropped!");
+///         pr_info!("Foo is being dropped!\n");
 ///     }
 /// }
 /// ```
@@ -1418,17 +1418,14 @@ impl_zeroable! {
     // SAFETY: `T: Zeroable` and `UnsafeCell` is `repr(transparent)`.
     {<T: ?Sized + Zeroable>} UnsafeCell<T>,
 
-    // SAFETY: All zeros is equivalent to `None` (option layout optimization guarantee).
+    // SAFETY: All zeros is equivalent to `None` (option layout optimization guarantee:
+    // https://doc.rust-lang.org/stable/std/option/index.html#representation).
     Option<NonZeroU8>, Option<NonZeroU16>, Option<NonZeroU32>, Option<NonZeroU64>,
     Option<NonZeroU128>, Option<NonZeroUsize>,
     Option<NonZeroI8>, Option<NonZeroI16>, Option<NonZeroI32>, Option<NonZeroI64>,
     Option<NonZeroI128>, Option<NonZeroIsize>,
-
-    // SAFETY: All zeros is equivalent to `None` (option layout optimization guarantee).
-    //
-    // In this case we are allowed to use `T: ?Sized`, since all zeros is the `None` variant.
-    {<T: ?Sized>} Option<NonNull<T>>,
-    {<T: ?Sized>} Option<KBox<T>>,
+    {<T>} Option<NonNull<T>>,
+    {<T>} Option<KBox<T>>,
 
     // SAFETY: `null` pointer is valid.
     //
diff --git a/rust/kernel/init/macros.rs b/rust/kernel/init/macros.rs
index 1fd146a83241..b7213962a6a5 100644
--- a/rust/kernel/init/macros.rs
+++ b/rust/kernel/init/macros.rs
@@ -45,7 +45,7 @@
 //! #[pinned_drop]
 //! impl PinnedDrop for Foo {
 //!     fn drop(self: Pin<&mut Self>) {
-//!         pr_info!("{self:p} is getting dropped.");
+//!         pr_info!("{self:p} is getting dropped.\n");
 //!     }
 //! }
 //!
@@ -412,7 +412,7 @@
 //! #[pinned_drop]
 //! impl PinnedDrop for Foo {
 //!     fn drop(self: Pin<&mut Self>) {
-//!         pr_info!("{self:p} is getting dropped.");
+//!         pr_info!("{self:p} is getting dropped.\n");
 //!     }
 //! }
 //! ```
@@ -423,7 +423,7 @@
 //! // `unsafe`, full path and the token parameter are added, everything else stays the same.
 //! unsafe impl ::kernel::init::PinnedDrop for Foo {
 //!     fn drop(self: Pin<&mut Self>, _: ::kernel::init::__internal::OnlyCallFromDrop) {
-//!         pr_info!("{self:p} is getting dropped.");
+//!         pr_info!("{self:p} is getting dropped.\n");
 //!     }
 //! }
 //! ```
diff --git a/rust/kernel/lib.rs b/rust/kernel/lib.rs
index 496ed32b0911..7697c60b2d1a 100644
--- a/rust/kernel/lib.rs
+++ b/rust/kernel/lib.rs
@@ -6,7 +6,7 @@
 //! usage by Rust code in the kernel and is shared by all of them.
 //!
 //! In other words, all the rest of the Rust code in the kernel (e.g. kernel
-//! modules written in Rust) depends on [`core`], [`alloc`] and this crate.
+//! modules written in Rust) depends on [`core`] and this crate.
 //!
 //! If you need a kernel C API that is not ported or wrapped yet here, then
 //! do so first instead of bypassing this crate.
@@ -46,6 +46,7 @@ pub mod device_id;
 pub mod devres;
 pub mod driver;
 pub mod error;
+pub mod faux;
 #[cfg(CONFIG_RUST_FW_LOADER_ABSTRACTIONS)]
 pub mod firmware;
 pub mod fs;
diff --git a/rust/kernel/rbtree.rs b/rust/kernel/rbtree.rs
index ee2731dad72d..0d1e75810664 100644
--- a/rust/kernel/rbtree.rs
+++ b/rust/kernel/rbtree.rs
@@ -1149,7 +1149,7 @@ pub struct VacantEntry<'a, K, V> {
 /// # Invariants
 /// - `parent` may be null if the new node becomes the root.
 /// - `child_field_of_parent` is a valid pointer to the left-child or right-child of `parent`. If `parent` is
-///     null, it is a pointer to the root of the [`RBTree`].
+///   null, it is a pointer to the root of the [`RBTree`].
 struct RawVacantEntry<'a, K, V> {
     rbtree: *mut RBTree<K, V>,
     /// The node that will become the parent of the new node if we insert one.
diff --git a/rust/kernel/sync.rs b/rust/kernel/sync.rs
index 3498fb344dc9..16eab9138b2b 100644
--- a/rust/kernel/sync.rs
+++ b/rust/kernel/sync.rs
@@ -30,28 +30,20 @@ pub struct LockClassKey(Opaque<bindings::lock_class_key>);
 unsafe impl Sync for LockClassKey {}
 
 impl LockClassKey {
-    /// Creates a new lock class key.
-    pub const fn new() -> Self {
-        Self(Opaque::uninit())
-    }
-
     pub(crate) fn as_ptr(&self) -> *mut bindings::lock_class_key {
         self.0.get()
     }
 }
 
-impl Default for LockClassKey {
-    fn default() -> Self {
-        Self::new()
-    }
-}
-
 /// Defines a new static lock class and returns a pointer to it.
 #[doc(hidden)]
 #[macro_export]
 macro_rules! static_lock_class {
     () => {{
-        static CLASS: $crate::sync::LockClassKey = $crate::sync::LockClassKey::new();
+        static CLASS: $crate::sync::LockClassKey =
+            // SAFETY: lockdep expects uninitialized memory when it's handed a statically allocated
+            // lock_class_key
+            unsafe { ::core::mem::MaybeUninit::uninit().assume_init() };
         &CLASS
     }};
 }
diff --git a/rust/kernel/sync/locked_by.rs b/rust/kernel/sync/locked_by.rs
index a7b244675c2b..61f100a45b35 100644
--- a/rust/kernel/sync/locked_by.rs
+++ b/rust/kernel/sync/locked_by.rs
@@ -55,7 +55,7 @@ use core::{cell::UnsafeCell, mem::size_of, ptr};
 /// fn print_bytes_used(dir: &Directory, file: &File) {
 ///     let guard = dir.inner.lock();
 ///     let inner_file = file.inner.access(&guard);
-///     pr_info!("{} {}", guard.bytes_used, inner_file.bytes_used);
+///     pr_info!("{} {}\n", guard.bytes_used, inner_file.bytes_used);
 /// }
 ///
 /// /// Increments `bytes_used` for both the directory and file.
diff --git a/rust/kernel/task.rs b/rust/kernel/task.rs
index 07bc22a7645c..38da555a2bdb 100644
--- a/rust/kernel/task.rs
+++ b/rust/kernel/task.rs
@@ -320,7 +320,7 @@ impl Task {
 
     /// Wakes up the task.
     pub fn wake_up(&self) {
-        // SAFETY: It's always safe to call `signal_pending` on a valid task, even if the task
+        // SAFETY: It's always safe to call `wake_up_process` on a valid task, even if the task
         // running.
         unsafe { bindings::wake_up_process(self.as_ptr()) };
     }
diff --git a/rust/kernel/workqueue.rs b/rust/kernel/workqueue.rs
index 0cd100d2aefb..b7be224cdf4b 100644
--- a/rust/kernel/workqueue.rs
+++ b/rust/kernel/workqueue.rs
@@ -60,7 +60,7 @@
 //!     type Pointer = Arc<MyStruct>;
 //!
 //!     fn run(this: Arc<MyStruct>) {
-//!         pr_info!("The value is: {}", this.value);
+//!         pr_info!("The value is: {}\n", this.value);
 //!     }
 //! }
 //!
@@ -108,7 +108,7 @@
 //!     type Pointer = Arc<MyStruct>;
 //!
 //!     fn run(this: Arc<MyStruct>) {
-//!         pr_info!("The value is: {}", this.value_1);
+//!         pr_info!("The value is: {}\n", this.value_1);
 //!     }
 //! }
 //!
@@ -116,7 +116,7 @@
 //!     type Pointer = Arc<MyStruct>;
 //!
 //!     fn run(this: Arc<MyStruct>) {
-//!         pr_info!("The second value is: {}", this.value_2);
+//!         pr_info!("The second value is: {}\n", this.value_2);
 //!     }
 //! }
 //!