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 --- samples/bpf/trace_output.bpf.c | 29 +++++++++++++++++++++++++++++ 1 file changed, 29 insertions(+) create mode 100644 samples/bpf/trace_output.bpf.c (limited to 'samples/bpf/trace_output.bpf.c') diff --git a/samples/bpf/trace_output.bpf.c b/samples/bpf/trace_output.bpf.c new file mode 100644 index 000000000..565a73b51 --- /dev/null +++ b/samples/bpf/trace_output.bpf.c @@ -0,0 +1,29 @@ +#include "vmlinux.h" +#include +#include + +struct { + __uint(type, BPF_MAP_TYPE_PERF_EVENT_ARRAY); + __uint(key_size, sizeof(int)); + __uint(value_size, sizeof(u32)); + __uint(max_entries, 2); +} my_map SEC(".maps"); + +SEC("ksyscall/write") +int bpf_prog1(struct pt_regs *ctx) +{ + struct S { + u64 pid; + u64 cookie; + } data; + + data.pid = bpf_get_current_pid_tgid(); + data.cookie = 0x12345678; + + bpf_perf_event_output(ctx, &my_map, 0, &data, sizeof(data)); + + return 0; +} + +char _license[] SEC("license") = "GPL"; +u32 _version SEC("version") = LINUX_VERSION_CODE; -- cgit v1.3.1