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/ceph/string_table.c | 106 ++++++++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 106 insertions(+) create mode 100644 net/ceph/string_table.c (limited to 'net/ceph/string_table.c') diff --git a/net/ceph/string_table.c b/net/ceph/string_table.c new file mode 100644 index 000000000..3191d9d16 --- /dev/null +++ b/net/ceph/string_table.c @@ -0,0 +1,106 @@ +// SPDX-License-Identifier: GPL-2.0 +#include +#include +#include +#include +#include + +static DEFINE_SPINLOCK(string_tree_lock); +static struct rb_root string_tree = RB_ROOT; + +struct ceph_string *ceph_find_or_create_string(const char* str, size_t len) +{ + struct ceph_string *cs, *exist; + struct rb_node **p, *parent; + int ret; + + exist = NULL; + spin_lock(&string_tree_lock); + p = &string_tree.rb_node; + while (*p) { + exist = rb_entry(*p, struct ceph_string, node); + ret = ceph_compare_string(exist, str, len); + if (ret > 0) + p = &(*p)->rb_left; + else if (ret < 0) + p = &(*p)->rb_right; + else + break; + exist = NULL; + } + if (exist && !kref_get_unless_zero(&exist->kref)) { + rb_erase(&exist->node, &string_tree); + RB_CLEAR_NODE(&exist->node); + exist = NULL; + } + spin_unlock(&string_tree_lock); + if (exist) + return exist; + + cs = kmalloc(sizeof(*cs) + len + 1, GFP_NOFS); + if (!cs) + return NULL; + + kref_init(&cs->kref); + cs->len = len; + memcpy(cs->str, str, len); + cs->str[len] = 0; + +retry: + exist = NULL; + parent = NULL; + p = &string_tree.rb_node; + spin_lock(&string_tree_lock); + while (*p) { + parent = *p; + exist = rb_entry(*p, struct ceph_string, node); + ret = ceph_compare_string(exist, str, len); + if (ret > 0) + p = &(*p)->rb_left; + else if (ret < 0) + p = &(*p)->rb_right; + else + break; + exist = NULL; + } + ret = 0; + if (!exist) { + rb_link_node(&cs->node, parent, p); + rb_insert_color(&cs->node, &string_tree); + } else if (!kref_get_unless_zero(&exist->kref)) { + rb_erase(&exist->node, &string_tree); + RB_CLEAR_NODE(&exist->node); + ret = -EAGAIN; + } + spin_unlock(&string_tree_lock); + if (ret == -EAGAIN) + goto retry; + + if (exist) { + kfree(cs); + cs = exist; + } + + return cs; +} +EXPORT_SYMBOL(ceph_find_or_create_string); + +void ceph_release_string(struct kref *ref) +{ + struct ceph_string *cs = container_of(ref, struct ceph_string, kref); + + spin_lock(&string_tree_lock); + if (!RB_EMPTY_NODE(&cs->node)) { + rb_erase(&cs->node, &string_tree); + RB_CLEAR_NODE(&cs->node); + } + spin_unlock(&string_tree_lock); + + kfree_rcu(cs, rcu); +} +EXPORT_SYMBOL(ceph_release_string); + +bool ceph_strings_empty(void) +{ + return RB_EMPTY_ROOT(&string_tree); +} -- cgit v1.3.1