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-rw-r--r--arch/x86/kernel/cpu/perf_event.c3
-rw-r--r--arch/x86/kernel/cpu/perf_event.h12
-rw-r--r--arch/x86/kernel/cpu/perf_event_intel.c69
-rw-r--r--arch/x86/kernel/cpu/perf_event_intel_ds.c6
-rw-r--r--arch/x86/kernel/cpu/perf_event_intel_uncore.c11
-rw-r--r--arch/x86/kernel/kprobes/core.c3
6 files changed, 91 insertions, 13 deletions
diff --git a/arch/x86/kernel/cpu/perf_event.c b/arch/x86/kernel/cpu/perf_event.c
index 2bdfbff8a4f6..2879ecdaac43 100644
--- a/arch/x86/kernel/cpu/perf_event.c
+++ b/arch/x86/kernel/cpu/perf_event.c
@@ -118,6 +118,9 @@ static int x86_pmu_extra_regs(u64 config, struct perf_event *event)
continue;
if (event->attr.config1 & ~er->valid_mask)
return -EINVAL;
+ /* Check if the extra msrs can be safely accessed*/
+ if (!er->extra_msr_access)
+ return -ENXIO;
reg->idx = er->idx;
reg->config = event->attr.config1;
diff --git a/arch/x86/kernel/cpu/perf_event.h b/arch/x86/kernel/cpu/perf_event.h
index 3b2f9bdd974b..8ade93111e03 100644
--- a/arch/x86/kernel/cpu/perf_event.h
+++ b/arch/x86/kernel/cpu/perf_event.h
@@ -295,14 +295,16 @@ struct extra_reg {
u64 config_mask;
u64 valid_mask;
int idx; /* per_xxx->regs[] reg index */
+ bool extra_msr_access;
};
#define EVENT_EXTRA_REG(e, ms, m, vm, i) { \
- .event = (e), \
- .msr = (ms), \
- .config_mask = (m), \
- .valid_mask = (vm), \
- .idx = EXTRA_REG_##i, \
+ .event = (e), \
+ .msr = (ms), \
+ .config_mask = (m), \
+ .valid_mask = (vm), \
+ .idx = EXTRA_REG_##i, \
+ .extra_msr_access = true, \
}
#define INTEL_EVENT_EXTRA_REG(event, msr, vm, idx) \
diff --git a/arch/x86/kernel/cpu/perf_event_intel.c b/arch/x86/kernel/cpu/perf_event_intel.c
index 07846d738bdb..2502d0d9d246 100644
--- a/arch/x86/kernel/cpu/perf_event_intel.c
+++ b/arch/x86/kernel/cpu/perf_event_intel.c
@@ -2182,6 +2182,41 @@ static void intel_snb_check_microcode(void)
}
}
+/*
+ * Under certain circumstances, access certain MSR may cause #GP.
+ * The function tests if the input MSR can be safely accessed.
+ */
+static bool check_msr(unsigned long msr, u64 mask)
+{
+ u64 val_old, val_new, val_tmp;
+
+ /*
+ * Read the current value, change it and read it back to see if it
+ * matches, this is needed to detect certain hardware emulators
+ * (qemu/kvm) that don't trap on the MSR access and always return 0s.
+ */
+ if (rdmsrl_safe(msr, &val_old))
+ return false;
+
+ /*
+ * Only change the bits which can be updated by wrmsrl.
+ */
+ val_tmp = val_old ^ mask;
+ if (wrmsrl_safe(msr, val_tmp) ||
+ rdmsrl_safe(msr, &val_new))
+ return false;
+
+ if (val_new != val_tmp)
+ return false;
+
+ /* Here it's sure that the MSR can be safely accessed.
+ * Restore the old value and return.
+ */
+ wrmsrl(msr, val_old);
+
+ return true;
+}
+
static __init void intel_sandybridge_quirk(void)
{
x86_pmu.check_microcode = intel_snb_check_microcode;
@@ -2271,7 +2306,8 @@ __init int intel_pmu_init(void)
union cpuid10_ebx ebx;
struct event_constraint *c;
unsigned int unused;
- int version;
+ struct extra_reg *er;
+ int version, i;
if (!cpu_has(&boot_cpu_data, X86_FEATURE_ARCH_PERFMON)) {
switch (boot_cpu_data.x86) {
@@ -2474,6 +2510,9 @@ __init int intel_pmu_init(void)
case 62: /* IvyBridge EP */
memcpy(hw_cache_event_ids, snb_hw_cache_event_ids,
sizeof(hw_cache_event_ids));
+ /* dTLB-load-misses on IVB is different than SNB */
+ hw_cache_event_ids[C(DTLB)][C(OP_READ)][C(RESULT_MISS)] = 0x8108; /* DTLB_LOAD_MISSES.DEMAND_LD_MISS_CAUSES_A_WALK */
+
memcpy(hw_cache_extra_regs, snb_hw_cache_extra_regs,
sizeof(hw_cache_extra_regs));
@@ -2574,6 +2613,34 @@ __init int intel_pmu_init(void)
}
}
+ /*
+ * Access LBR MSR may cause #GP under certain circumstances.
+ * E.g. KVM doesn't support LBR MSR
+ * Check all LBT MSR here.
+ * Disable LBR access if any LBR MSRs can not be accessed.
+ */
+ if (x86_pmu.lbr_nr && !check_msr(x86_pmu.lbr_tos, 0x3UL))
+ x86_pmu.lbr_nr = 0;
+ for (i = 0; i < x86_pmu.lbr_nr; i++) {
+ if (!(check_msr(x86_pmu.lbr_from + i, 0xffffUL) &&
+ check_msr(x86_pmu.lbr_to + i, 0xffffUL)))
+ x86_pmu.lbr_nr = 0;
+ }
+
+ /*
+ * Access extra MSR may cause #GP under certain circumstances.
+ * E.g. KVM doesn't support offcore event
+ * Check all extra_regs here.
+ */
+ if (x86_pmu.extra_regs) {
+ for (er = x86_pmu.extra_regs; er->msr; er++) {
+ er->extra_msr_access = check_msr(er->msr, 0x1ffUL);
+ /* Disable LBR select mapping */
+ if ((er->idx == EXTRA_REG_LBR) && !er->extra_msr_access)
+ x86_pmu.lbr_sel_map = NULL;
+ }
+ }
+
/* Support full width counters using alternative MSR range */
if (x86_pmu.intel_cap.full_width_write) {
x86_pmu.max_period = x86_pmu.cntval_mask;
diff --git a/arch/x86/kernel/cpu/perf_event_intel_ds.c b/arch/x86/kernel/cpu/perf_event_intel_ds.c
index 980970cb744d..696ade311ded 100644
--- a/arch/x86/kernel/cpu/perf_event_intel_ds.c
+++ b/arch/x86/kernel/cpu/perf_event_intel_ds.c
@@ -311,9 +311,11 @@ static int alloc_bts_buffer(int cpu)
if (!x86_pmu.bts)
return 0;
- buffer = kzalloc_node(BTS_BUFFER_SIZE, GFP_KERNEL, node);
- if (unlikely(!buffer))
+ buffer = kzalloc_node(BTS_BUFFER_SIZE, GFP_KERNEL | __GFP_NOWARN, node);
+ if (unlikely(!buffer)) {
+ WARN_ONCE(1, "%s: BTS buffer allocation failure\n", __func__);
return -ENOMEM;
+ }
max = BTS_BUFFER_SIZE / BTS_RECORD_SIZE;
thresh = max / 16;
diff --git a/arch/x86/kernel/cpu/perf_event_intel_uncore.c b/arch/x86/kernel/cpu/perf_event_intel_uncore.c
index 65bbbea38b9c..ae6552a0701f 100644
--- a/arch/x86/kernel/cpu/perf_event_intel_uncore.c
+++ b/arch/x86/kernel/cpu/perf_event_intel_uncore.c
@@ -550,16 +550,16 @@ static struct extra_reg snbep_uncore_cbox_extra_regs[] = {
SNBEP_CBO_EVENT_EXTRA_REG(0x4134, 0xffff, 0x6),
SNBEP_CBO_EVENT_EXTRA_REG(0x0135, 0xffff, 0x8),
SNBEP_CBO_EVENT_EXTRA_REG(0x0335, 0xffff, 0x8),
- SNBEP_CBO_EVENT_EXTRA_REG(0x4135, 0xffff, 0xc),
- SNBEP_CBO_EVENT_EXTRA_REG(0x4335, 0xffff, 0xc),
+ SNBEP_CBO_EVENT_EXTRA_REG(0x4135, 0xffff, 0xa),
+ SNBEP_CBO_EVENT_EXTRA_REG(0x4335, 0xffff, 0xa),
SNBEP_CBO_EVENT_EXTRA_REG(0x4435, 0xffff, 0x2),
SNBEP_CBO_EVENT_EXTRA_REG(0x4835, 0xffff, 0x2),
SNBEP_CBO_EVENT_EXTRA_REG(0x4a35, 0xffff, 0x2),
SNBEP_CBO_EVENT_EXTRA_REG(0x5035, 0xffff, 0x2),
SNBEP_CBO_EVENT_EXTRA_REG(0x0136, 0xffff, 0x8),
SNBEP_CBO_EVENT_EXTRA_REG(0x0336, 0xffff, 0x8),
- SNBEP_CBO_EVENT_EXTRA_REG(0x4136, 0xffff, 0xc),
- SNBEP_CBO_EVENT_EXTRA_REG(0x4336, 0xffff, 0xc),
+ SNBEP_CBO_EVENT_EXTRA_REG(0x4136, 0xffff, 0xa),
+ SNBEP_CBO_EVENT_EXTRA_REG(0x4336, 0xffff, 0xa),
SNBEP_CBO_EVENT_EXTRA_REG(0x4436, 0xffff, 0x2),
SNBEP_CBO_EVENT_EXTRA_REG(0x4836, 0xffff, 0x2),
SNBEP_CBO_EVENT_EXTRA_REG(0x4a36, 0xffff, 0x2),
@@ -1222,6 +1222,7 @@ static struct extra_reg ivt_uncore_cbox_extra_regs[] = {
SNBEP_CBO_EVENT_EXTRA_REG(SNBEP_CBO_PMON_CTL_TID_EN,
SNBEP_CBO_PMON_CTL_TID_EN, 0x1),
SNBEP_CBO_EVENT_EXTRA_REG(0x1031, 0x10ff, 0x2),
+
SNBEP_CBO_EVENT_EXTRA_REG(0x1134, 0xffff, 0x4),
SNBEP_CBO_EVENT_EXTRA_REG(0x4134, 0xffff, 0xc),
SNBEP_CBO_EVENT_EXTRA_REG(0x5134, 0xffff, 0xc),
@@ -1245,7 +1246,7 @@ static struct extra_reg ivt_uncore_cbox_extra_regs[] = {
SNBEP_CBO_EVENT_EXTRA_REG(0x8335, 0xffff, 0x10),
SNBEP_CBO_EVENT_EXTRA_REG(0x0136, 0xffff, 0x10),
SNBEP_CBO_EVENT_EXTRA_REG(0x0336, 0xffff, 0x10),
- SNBEP_CBO_EVENT_EXTRA_REG(0x2336, 0xffff, 0x10),
+ SNBEP_CBO_EVENT_EXTRA_REG(0x2136, 0xffff, 0x10),
SNBEP_CBO_EVENT_EXTRA_REG(0x2336, 0xffff, 0x10),
SNBEP_CBO_EVENT_EXTRA_REG(0x4136, 0xffff, 0x18),
SNBEP_CBO_EVENT_EXTRA_REG(0x4336, 0xffff, 0x18),
diff --git a/arch/x86/kernel/kprobes/core.c b/arch/x86/kernel/kprobes/core.c
index 7596df664901..67e6d19ef1be 100644
--- a/arch/x86/kernel/kprobes/core.c
+++ b/arch/x86/kernel/kprobes/core.c
@@ -574,6 +574,9 @@ int kprobe_int3_handler(struct pt_regs *regs)
struct kprobe *p;
struct kprobe_ctlblk *kcb;
+ if (user_mode_vm(regs))
+ return 0;
+
addr = (kprobe_opcode_t *)(regs->ip - sizeof(kprobe_opcode_t));
/*
* We don't want to be preempted for the entire