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 --- arch/x86/lib/cache-smp.c | 44 ++++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 44 insertions(+) create mode 100644 arch/x86/lib/cache-smp.c (limited to 'arch/x86/lib/cache-smp.c') diff --git a/arch/x86/lib/cache-smp.c b/arch/x86/lib/cache-smp.c new file mode 100644 index 000000000..7d3edd6de --- /dev/null +++ b/arch/x86/lib/cache-smp.c @@ -0,0 +1,44 @@ +// SPDX-License-Identifier: GPL-2.0 +#include +#include +#include + +static void __wbinvd(void *dummy) +{ + wbinvd(); +} + +void wbinvd_on_cpu(int cpu) +{ + smp_call_function_single(cpu, __wbinvd, NULL, 1); +} +EXPORT_SYMBOL_FOR_KVM(wbinvd_on_cpu); + +void wbinvd_on_all_cpus(void) +{ + on_each_cpu(__wbinvd, NULL, 1); +} +EXPORT_SYMBOL(wbinvd_on_all_cpus); + +void wbinvd_on_cpus_mask(struct cpumask *cpus) +{ + on_each_cpu_mask(cpus, __wbinvd, NULL, 1); +} +EXPORT_SYMBOL_FOR_KVM(wbinvd_on_cpus_mask); + +static void __wbnoinvd(void *dummy) +{ + wbnoinvd(); +} + +void wbnoinvd_on_all_cpus(void) +{ + on_each_cpu(__wbnoinvd, NULL, 1); +} +EXPORT_SYMBOL_FOR_KVM(wbnoinvd_on_all_cpus); + +void wbnoinvd_on_cpus_mask(struct cpumask *cpus) +{ + on_each_cpu_mask(cpus, __wbnoinvd, NULL, 1); +} +EXPORT_SYMBOL_FOR_KVM(wbnoinvd_on_cpus_mask); -- cgit v1.3.1