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 --- include/drm/drm_util.h | 69 ++++++++++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 69 insertions(+) create mode 100644 include/drm/drm_util.h (limited to 'include/drm/drm_util.h') diff --git a/include/drm/drm_util.h b/include/drm/drm_util.h new file mode 100644 index 000000000..440199618 --- /dev/null +++ b/include/drm/drm_util.h @@ -0,0 +1,69 @@ +/* + * Internal Header for the Direct Rendering Manager + * + * Copyright 2018 Intel Corporation + * + * Permission is hereby granted, free of charge, to any person obtaining a + * copy of this software and associated documentation files (the "Software"), + * to deal in the Software without restriction, including without limitation + * the rights to use, copy, modify, merge, publish, distribute, sublicense, + * and/or sell copies of the Software, and to permit persons to whom the + * Software is furnished to do so, subject to the following conditions: + * + * The above copyright notice and this permission notice (including the next + * paragraph) shall be included in all copies or substantial portions of the + * Software. + * + * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR + * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, + * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL + * VA LINUX SYSTEMS AND/OR ITS SUPPLIERS BE LIABLE FOR ANY CLAIM, DAMAGES OR + * OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, + * ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR + * OTHER DEALINGS IN THE SOFTWARE. + */ + +#ifndef _DRM_UTIL_H_ +#define _DRM_UTIL_H_ + +/** + * DOC: drm utils + * + * Macros and inline functions that does not naturally belong in other places + */ + +#include +#include +#include +#include +#include + +/* + * Use EXPORT_SYMBOL_FOR_TESTS_ONLY() for functions that shall + * only be visible for drmselftests. + */ +#if defined(CONFIG_DRM_EXPORT_FOR_TESTS) +#define EXPORT_SYMBOL_FOR_TESTS_ONLY(x) EXPORT_SYMBOL(x) +#else +#define EXPORT_SYMBOL_FOR_TESTS_ONLY(x) +#endif + +/** + * drm_can_sleep - returns true if currently okay to sleep + * + * This function shall not be used in new code. + * The check for running in atomic context may not work - see linux/preempt.h. + * + * FIXME: All users of drm_can_sleep should be removed (see todo.rst) + * + * Returns: + * False if kgdb is active, we are in atomic context or irqs are disabled. + */ +static inline bool drm_can_sleep(void) +{ + if (in_atomic() || in_dbg_master() || irqs_disabled()) + return false; + return true; +} + +#endif -- cgit v1.3.1