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-rw-r--r--arch/x86/kernel/cpu/perf_event.c20
-rw-r--r--arch/x86/kernel/cpu/perf_event_amd.c4
2 files changed, 22 insertions, 2 deletions
diff --git a/arch/x86/kernel/cpu/perf_event.c b/arch/x86/kernel/cpu/perf_event.c
index ed6310183ef..6d75b9145b1 100644
--- a/arch/x86/kernel/cpu/perf_event.c
+++ b/arch/x86/kernel/cpu/perf_event.c
@@ -381,6 +381,20 @@ static void release_pmc_hardware(void) {}
#endif
+static bool check_hw_exists(void)
+{
+ u64 val, val_new = 0;
+ int ret = 0;
+
+ val = 0xabcdUL;
+ ret |= checking_wrmsrl(x86_pmu.perfctr, val);
+ ret |= rdmsrl_safe(x86_pmu.perfctr, &val_new);
+ if (ret || val != val_new)
+ return false;
+
+ return true;
+}
+
static void reserve_ds_buffers(void);
static void release_ds_buffers(void);
@@ -1372,6 +1386,12 @@ void __init init_hw_perf_events(void)
pmu_check_apic();
+ /* sanity check that the hardware exists or is emulated */
+ if (!check_hw_exists()) {
+ pr_cont("Broken PMU hardware detected, software events only.\n");
+ return;
+ }
+
pr_cont("%s PMU driver.\n", x86_pmu.name);
if (x86_pmu.quirks)
diff --git a/arch/x86/kernel/cpu/perf_event_amd.c b/arch/x86/kernel/cpu/perf_event_amd.c
index 46d58448c3a..e421b8cd694 100644
--- a/arch/x86/kernel/cpu/perf_event_amd.c
+++ b/arch/x86/kernel/cpu/perf_event_amd.c
@@ -280,11 +280,11 @@ static struct amd_nb *amd_alloc_nb(int cpu, int nb_id)
struct amd_nb *nb;
int i;
- nb = kmalloc(sizeof(struct amd_nb), GFP_KERNEL);
+ nb = kmalloc_node(sizeof(struct amd_nb), GFP_KERNEL | __GFP_ZERO,
+ cpu_to_node(cpu));
if (!nb)
return NULL;
- memset(nb, 0, sizeof(*nb));
nb->nb_id = nb_id;
/*