x86/resctrl: Free rmid_ptrs from resctrl_exit()

rmid_ptrs[] is allocated from dom_data_init() but never free()d.

While the exit text ends up in the linker script's DISCARD section,
the direction of travel is for resctrl to be/have loadable modules.

Add resctrl_put_mon_l3_config() to cleanup any memory allocated
by rdt_get_mon_l3_config().

There is no reason to backport this to a stable kernel.

Signed-off-by: James Morse <james.morse@arm.com>
Signed-off-by: Borislav Petkov (AMD) <bp@alien8.de>
Reviewed-by: Babu Moger <babu.moger@amd.com>
Reviewed-by: Reinette Chatre <reinette.chatre@intel.com>
Tested-by: Babu Moger <babu.moger@amd.com>
Tested-by: Carl Worth <carl@os.amperecomputing.com> # arm64
Link: https://lore.kernel.org/r/20240213184438.16675-3-james.morse@arm.com
Signed-off-by: Borislav Petkov (AMD) <bp@alien8.de>

diff --git a/arch/x86/kernel/cpu/resctrl/core.c b/arch/x86/kernel/cpu/resctrl/core.c
index aa9810a64258ec3ba7c0fd89275d88df368389e5..9641c42d0f8563137fcbf7d3c0bf59b144880a10 100644 (file)
--- a/arch/x86/kernel/cpu/resctrl/core.c
+++ b/arch/x86/kernel/cpu/resctrl/core.c
@@ -990,8 +990,14 @@ late_initcall(resctrl_late_init);
 
 static void __exit resctrl_exit(void)
 {
+       struct rdt_resource *r = &rdt_resources_all[RDT_RESOURCE_L3].r_resctrl;
+
        cpuhp_remove_state(rdt_online);
+
        rdtgroup_exit();
+
+       if (r->mon_capable)
+               rdt_put_mon_l3_config();
 }
 
 __exitcall(resctrl_exit);

diff --git a/arch/x86/kernel/cpu/resctrl/internal.h b/arch/x86/kernel/cpu/resctrl/internal.h
index 52e7e7deee1068d71ed45ff31bf458c482188182..61c763604fc98a9ebd47a08088094460a204c421 100644 (file)
--- a/arch/x86/kernel/cpu/resctrl/internal.h
+++ b/arch/x86/kernel/cpu/resctrl/internal.h
@@ -544,6 +544,7 @@ void closid_free(int closid);
 int alloc_rmid(void);
 void free_rmid(u32 rmid);
 int rdt_get_mon_l3_config(struct rdt_resource *r);
+void __exit rdt_put_mon_l3_config(void);
 bool __init rdt_cpu_has(int flag);
 void mon_event_count(void *info);
 int rdtgroup_mondata_show(struct seq_file *m, void *arg);

diff --git a/arch/x86/kernel/cpu/resctrl/monitor.c b/arch/x86/kernel/cpu/resctrl/monitor.c
index 3a6c069614eb84304dd1fec5506ef97cf358790e..3a73db0579d855f3a97b2836a5fc621fa0df705b 100644 (file)
--- a/arch/x86/kernel/cpu/resctrl/monitor.c
+++ b/arch/x86/kernel/cpu/resctrl/monitor.c
@@ -719,6 +719,16 @@ static int dom_data_init(struct rdt_resource *r)
        return 0;
 }
 
+static void __exit dom_data_exit(void)
+{
+       mutex_lock(&rdtgroup_mutex);
+
+       kfree(rmid_ptrs);
+       rmid_ptrs = NULL;
+
+       mutex_unlock(&rdtgroup_mutex);
+}
+
 static struct mon_evt llc_occupancy_event = {
        .name           = "llc_occupancy",
        .evtid          = QOS_L3_OCCUP_EVENT_ID,
@@ -814,6 +824,11 @@ int __init rdt_get_mon_l3_config(struct rdt_resource *r)
        return 0;
 }
 
+void __exit rdt_put_mon_l3_config(void)
+{
+       dom_data_exit();
+}
+
 void __init intel_rdt_mbm_apply_quirk(void)
 {
        int cf_index;