From 27600805e62f800bacf990354632eae4e487d34c Mon Sep 17 00:00:00 2001 From: Yazen Ghannam Date: Thu, 3 Sep 2026 10:43:25 -0500 Subject: x86/amd_node: Fix PCI device reference counting in amd_smn_init() The local "root" pointer is a temporary variable used during the device search. Therefore, refcount related to the search iterators should be cleaned up after the search is complete. Use the __free() cleanup macro to ensure the refcount is decremented when the temporary pointer goes out of scope. Additionally, increment the refcount when caching a root pointer. This ensures the in-use refcount is separate from the temporary search refcounting. Finally, drop the redundant "root = NULL" before the second search loop. The pci_get_class() iterator always decrements the refcount of its "from" argument, so the first loop can only fall through with "root" already NULL. Fixes: 0a4b61d9c2e4 ("x86/amd_node: Fix AMD root device caching") Closes: https://sashiko.dev/#/patchset/20260806160159.230453-1-jason.andryuk%40amd.com Reported-by: Sashiko Assisted-by: LLM Signed-off-by: Yazen Ghannam Signed-off-by: Borislav Petkov (AMD) Reviewed-by: Mario Limonciello (AMD) Cc: Link: https://patch.msgid.link/20260903154325.74343-1-yazen.ghannam@amd.com --- rust/build_error.rs | 31 +++++++++++++++++++++++++++++++ 1 file changed, 31 insertions(+) create mode 100644 rust/build_error.rs (limited to 'rust/build_error.rs') diff --git a/rust/build_error.rs b/rust/build_error.rs new file mode 100644 index 000000000..fa24eeef9 --- /dev/null +++ b/rust/build_error.rs @@ -0,0 +1,31 @@ +// SPDX-License-Identifier: GPL-2.0 + +//! Build-time error. +//! +//! This crate provides a [const function][const-functions] `build_error`, which will panic in +//! compile-time if executed in [const context][const-context], and will cause a build error +//! if not executed at compile time and the optimizer does not optimise away the call. +//! +//! It is used by `build_assert!` in the kernel crate, allowing checking of +//! conditions that could be checked statically, but could not be enforced in +//! Rust yet (e.g. perform some checks in [const functions][const-functions], but those +//! functions could still be called in the runtime). +//! +//! For details on constant evaluation in Rust, please see the [Reference][const-eval]. +//! +//! [const-eval]: https://doc.rust-lang.org/reference/const_eval.html +//! [const-functions]: https://doc.rust-lang.org/reference/const_eval.html#const-functions +//! [const-context]: https://doc.rust-lang.org/reference/const_eval.html#const-context + +#![no_std] + +/// Panics if executed in [const context][const-context], or triggers a build error if not. +/// +/// [const-context]: https://doc.rust-lang.org/reference/const_eval.html#const-context +#[inline(never)] +#[cold] +#[export_name = "rust_build_error"] +#[track_caller] +pub const fn build_error(msg: &'static str) -> ! { + panic!("{}", msg); +} -- cgit v1.3.1