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/zerocopy-derive/derive/unaligned.rs | 80 ++++++++++++++++++++++++++++++++ 1 file changed, 80 insertions(+) create mode 100644 rust/zerocopy-derive/derive/unaligned.rs (limited to 'rust/zerocopy-derive/derive/unaligned.rs') diff --git a/rust/zerocopy-derive/derive/unaligned.rs b/rust/zerocopy-derive/derive/unaligned.rs new file mode 100644 index 000000000..7c97d62e2 --- /dev/null +++ b/rust/zerocopy-derive/derive/unaligned.rs @@ -0,0 +1,80 @@ +// SPDX-License-Identifier: (BSD-2-Clause OR Apache-2.0) OR MIT +// +use proc_macro2::{Span, TokenStream}; +use syn::{Data, DataEnum, DataStruct, DataUnion, Error}; + +use crate::{ + repr::{EnumRepr, StructUnionRepr}, + util::{Ctx, FieldBounds, ImplBlockBuilder, Trait}, +}; + +pub(crate) fn derive_unaligned(ctx: &Ctx, _top_level: Trait) -> Result { + match &ctx.ast.data { + Data::Struct(strct) => derive_unaligned_struct(ctx, strct), + Data::Enum(enm) => derive_unaligned_enum(ctx, enm), + Data::Union(unn) => derive_unaligned_union(ctx, unn), + } +} + +/// A struct is `Unaligned` if: +/// - `repr(align)` is no more than 1 and either +/// - `repr(C)` or `repr(transparent)` and +/// - all fields `Unaligned` +/// - `repr(packed)` +fn derive_unaligned_struct(ctx: &Ctx, strct: &DataStruct) -> Result { + let repr = StructUnionRepr::from_attrs(&ctx.ast.attrs)?; + repr.unaligned_validate_no_align_gt_1()?; + + let field_bounds = if repr.is_packed_1() { + FieldBounds::None + } else if repr.is_c() || repr.is_transparent() { + FieldBounds::ALL_SELF + } else { + return ctx.error_or_skip(Error::new( + Span::call_site(), + "must have #[repr(C)], #[repr(transparent)], or #[repr(packed)] attribute in order to guarantee this type's alignment", + )); + }; + + Ok(ImplBlockBuilder::new(ctx, strct, Trait::Unaligned, field_bounds).build()) +} + +/// An enum is `Unaligned` if: +/// - No `repr(align(N > 1))` +/// - `repr(u8)` or `repr(i8)` +fn derive_unaligned_enum(ctx: &Ctx, enm: &DataEnum) -> Result { + let repr = EnumRepr::from_attrs(&ctx.ast.attrs)?; + repr.unaligned_validate_no_align_gt_1()?; + + if !repr.is_u8() && !repr.is_i8() { + return ctx.error_or_skip(Error::new( + Span::call_site(), + "must have #[repr(u8)] or #[repr(i8)] attribute in order to guarantee this type's alignment", + )); + } + + Ok(ImplBlockBuilder::new(ctx, enm, Trait::Unaligned, FieldBounds::ALL_SELF).build()) +} + +/// Like structs, a union is `Unaligned` if: +/// - `repr(align)` is no more than 1 and either +/// - `repr(C)` or `repr(transparent)` and +/// - all fields `Unaligned` +/// - `repr(packed)` +fn derive_unaligned_union(ctx: &Ctx, unn: &DataUnion) -> Result { + let repr = StructUnionRepr::from_attrs(&ctx.ast.attrs)?; + repr.unaligned_validate_no_align_gt_1()?; + + let field_type_trait_bounds = if repr.is_packed_1() { + FieldBounds::None + } else if repr.is_c() || repr.is_transparent() { + FieldBounds::ALL_SELF + } else { + return ctx.error_or_skip(Error::new( + Span::call_site(), + "must have #[repr(C)], #[repr(transparent)], or #[repr(packed)] attribute in order to guarantee this type's alignment", + )); + }; + + Ok(ImplBlockBuilder::new(ctx, unn, Trait::Unaligned, field_type_trait_bounds).build()) +} -- cgit v1.3.1