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 --- net/sched/em_cmp.c | 99 ++++++++++++++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 99 insertions(+) create mode 100644 net/sched/em_cmp.c (limited to 'net/sched/em_cmp.c') diff --git a/net/sched/em_cmp.c b/net/sched/em_cmp.c new file mode 100644 index 000000000..48c1bce74 --- /dev/null +++ b/net/sched/em_cmp.c @@ -0,0 +1,99 @@ +// SPDX-License-Identifier: GPL-2.0-or-later +/* + * net/sched/em_cmp.c Simple packet data comparison ematch + * + * Authors: Thomas Graf + */ + +#include +#include +#include +#include +#include +#include +#include + +static inline int cmp_needs_transformation(struct tcf_em_cmp *cmp) +{ + return unlikely(cmp->flags & TCF_EM_CMP_TRANS); +} + +static int em_cmp_match(struct sk_buff *skb, struct tcf_ematch *em, + struct tcf_pkt_info *info) +{ + struct tcf_em_cmp *cmp = (struct tcf_em_cmp *) em->data; + unsigned char *ptr = tcf_get_base_ptr(skb, cmp->layer); + u32 val = 0; + + if (!ptr) + return 0; + ptr += cmp->off; + if (!tcf_valid_offset(skb, ptr, cmp->align)) + return 0; + + switch (cmp->align) { + case TCF_EM_ALIGN_U8: + val = *ptr; + break; + + case TCF_EM_ALIGN_U16: + val = get_unaligned_be16(ptr); + + if (cmp_needs_transformation(cmp)) + val = be16_to_cpu(val); + break; + + case TCF_EM_ALIGN_U32: + /* Worth checking boundaries? The branching seems + * to get worse. Visit again. + */ + val = get_unaligned_be32(ptr); + + if (cmp_needs_transformation(cmp)) + val = be32_to_cpu(val); + break; + + default: + return 0; + } + + if (cmp->mask) + val &= cmp->mask; + + switch (cmp->opnd) { + case TCF_EM_OPND_EQ: + return val == cmp->val; + case TCF_EM_OPND_LT: + return val < cmp->val; + case TCF_EM_OPND_GT: + return val > cmp->val; + } + + return 0; +} + +static struct tcf_ematch_ops em_cmp_ops = { + .kind = TCF_EM_CMP, + .datalen = sizeof(struct tcf_em_cmp), + .match = em_cmp_match, + .owner = THIS_MODULE, + .link = LIST_HEAD_INIT(em_cmp_ops.link) +}; + +static int __init init_em_cmp(void) +{ + return tcf_em_register(&em_cmp_ops); +} + +static void __exit exit_em_cmp(void) +{ + tcf_em_unregister(&em_cmp_ops); +} + +MODULE_DESCRIPTION("ematch classifier for basic data types(8/16/32 bit) against skb data"); +MODULE_LICENSE("GPL"); + +module_init(init_em_cmp); +module_exit(exit_em_cmp); + +MODULE_ALIAS_TCF_EMATCH(TCF_EM_CMP); -- cgit v1.3.1