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X-MS-Exchange-Transport-CrossTenantHeadersStamped: MN6PR11MB8169 X-OriginatorOrg: intel.com On 6/2/26 8:27 PM, Reinette Chatre wrote: > diff --git a/arch/x86/kernel/cpu/resctrl/ctrlmondata.c b/arch/x86/kernel/cpu/resctrl/ctrlmondata.c > index b20e705606b8..e74f1ed54b86 100644 > --- a/arch/x86/kernel/cpu/resctrl/ctrlmondata.c > +++ b/arch/x86/kernel/cpu/resctrl/ctrlmondata.c > @@ -53,7 +53,7 @@ int resctrl_arch_update_domains(struct rdt_resource *r, u32 closid) > /* Walking r->domains, ensure it can't race with cpuhp */ > lockdep_assert_cpus_held(); > > - list_for_each_entry(d, &r->ctrl_domains, hdr.list) { > + list_for_each_entry_rcu(d, &r->ctrl_domains, hdr.list, lockdep_is_cpus_held()) { > hw_dom = resctrl_to_arch_ctrl_dom(d); > msr_param.res = NULL; > for (t = 0; t < CDP_NUM_TYPES; t++) { Sashiko [1] pointed out that no stub exists for lockdep_is_cpus_held() when CONFIG_HOTPLUG_CPU is disabled. Before this series lockdep_is_cpus_held() only has one caller and it protects the call with an IS_ENABLED(CONFIG_HOTPLUG_CPU) check. This caught me as I am more familiar with the style of lockdep_is_held(). I find it safer to not need to prefix all lockdep_is_cpus_held() calls with an IS_ENABLED(CONFIG_HOTPLUG_CPU) check so I submitted an independent change to CPU hotplug to add the stubs [2]. Thanks to Thomas this was just merged to smp/core branch of tip. In the mean time, I believe it to be unlikely that anybody would disable CONFIG_SMP when using resctrl and CONFIG_HOTPLUG_CPU cannot be disabled by user and depends on CONFIG_SMP per: arch/x86/Kconfig: config HOTPLUG_CPU def_bool y depends on SMP Reinette [1] https://sashiko.dev/#/patchset/cover.1780456704.git.reinette.chatre%40intel.com?part=1 [2] https://lore.kernel.org/lkml/cover.1780543665.git.reinette.chatre@intel.com/