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/helpers/helpers.c | 108 +++++++++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 108 insertions(+) create mode 100644 rust/helpers/helpers.c (limited to 'rust/helpers/helpers.c') diff --git a/rust/helpers/helpers.c b/rust/helpers/helpers.c new file mode 100644 index 000000000..440fb7638 --- /dev/null +++ b/rust/helpers/helpers.c @@ -0,0 +1,108 @@ +// SPDX-License-Identifier: GPL-2.0 +/* + * Non-trivial C macros cannot be used in Rust. Similarly, inlined C functions + * cannot be called either. This file explicitly creates functions ("helpers") + * that wrap those so that they can be called from Rust. + * + * Sorted alphabetically. + */ + +#include + +#ifdef __BINDGEN__ +// Omit `inline` for bindgen as it ignores inline functions. +#define __rust_helper +#else +// The helper functions are all inline functions. +// +// We use `__always_inline` here to bypass LLVM inlining checks, in case the +// helpers are inlined directly into Rust CGUs. +// +// The LLVM inlining checks are false positives: +// * LLVM doesn't want to inline functions compiled with +// `-fno-delete-null-pointer-checks` with code compiled without. +// The C CGUs all have this enabled and Rust CGUs don't. Inlining is okay +// since this is one of the hardening features that does not change the ABI, +// and we shouldn't have null pointer dereferences in these helpers. +// * LLVM doesn't want to inline functions with different list of builtins. C +// side has `-fno-builtin-wcslen`; `wcslen` is not a Rust builtin, so they +// should be compatible, but LLVM does not perform inlining due to attributes +// mismatch. +// * clang and Rust doesn't have the exact target string. Clang generates +// `+cmov,+cx8,+fxsr` but Rust doesn't enable them (in fact, Rust will +// complain if `-Ctarget-feature=+cmov,+cx8,+fxsr` is used). x86-64 always +// enable these features, so they are in fact the same target string, but +// LLVM doesn't understand this and so inlining is inhibited. This can be +// bypassed with `--ignore-tti-inline-compatible`, but this is a hidden +// option. +#define __rust_helper __always_inline +#endif + +#include "atomic.c" +#include "atomic_ext.c" +#include "auxiliary.c" +#include "barrier.c" +#include "binder.c" +#include "bitmap.c" +#include "bitops.c" +#include "blk.c" +#include "bug.c" +#include "build_assert.c" +#include "build_bug.c" +#include "clk.c" +#include "completion.c" +#include "cpu.c" +#include "cpufreq.c" +#include "cpumask.c" +#include "cred.c" +#include "device.c" +#include "dma.c" +#ifdef CONFIG_DMA_SHARED_BUFFER +#include "dma-resv.c" +#endif +#include "drm.c" +#include "drm_gpuvm.c" +#include "err.c" +#include "fs.c" +#include "fwctl.c" +#include "gpu.c" +#include "interrupt.c" +#include "io.c" +#include "irq.c" +#include "jump_label.c" +#include "kunit.c" +#include "list.c" +#include "maple_tree.c" +#include "mm.c" +#include "mutex.c" +#include "net/genetlink.c" +#include "of.c" +#include "page.c" +#include "pci.c" +#include "pid_namespace.c" +#include "platform.c" +#include "poll.c" +#include "processor.c" +#include "property.c" +#include "pwm.c" +#include "rbtree.c" +#include "rcu.c" +#include "refcount.c" +#include "regulator.c" +#include "scatterlist.c" +#include "security.c" +#include "serdev.c" +#include "signal.c" +#include "slab.c" +#include "spinlock.c" +#include "string.c" +#include "srcu.c" +#include "sync.c" +#include "task.c" +#include "time.c" +#include "uaccess.c" +#include "usb.c" +#include "vmalloc.c" +#include "wait.c" +#include "workqueue.c" +#include "xarray.c" -- cgit v1.3.1