[GIT PULL] perf fixes
From: Ingo Molnar
Date: Sun Feb 17 2019 - 05:10:59 EST
Linus,
Please pull the latest perf-urgent-for-linus git tree from:
git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip.git perf-urgent-for-linus
# HEAD: 528871b456026e6127d95b1b2bd8e3a003dc1614 perf/core: Fix impossible ring-buffer sizes warning
Two fixes on the kernel side: fix an over-eager condition that failed
larger perf ring-buffer sizes, plus fix crashes in the Intel BTS code for
a corner case, found by fuzzing.
Thanks,
Ingo
------------------>
Ingo Molnar (1):
perf/core: Fix impossible ring-buffer sizes warning
Jiri Olsa (1):
perf/x86: Add check_period PMU callback
arch/x86/events/core.c | 14 ++++++++++++++
arch/x86/events/intel/core.c | 9 +++++++++
arch/x86/events/perf_event.h | 16 ++++++++++++++--
include/linux/perf_event.h | 5 +++++
kernel/events/core.c | 16 ++++++++++++++++
kernel/events/ring_buffer.c | 2 +-
6 files changed, 59 insertions(+), 3 deletions(-)
diff --git a/arch/x86/events/core.c b/arch/x86/events/core.c
index 374a19712e20..b684f0294f35 100644
--- a/arch/x86/events/core.c
+++ b/arch/x86/events/core.c
@@ -2278,6 +2278,19 @@ void perf_check_microcode(void)
x86_pmu.check_microcode();
}
+static int x86_pmu_check_period(struct perf_event *event, u64 value)
+{
+ if (x86_pmu.check_period && x86_pmu.check_period(event, value))
+ return -EINVAL;
+
+ if (value && x86_pmu.limit_period) {
+ if (x86_pmu.limit_period(event, value) > value)
+ return -EINVAL;
+ }
+
+ return 0;
+}
+
static struct pmu pmu = {
.pmu_enable = x86_pmu_enable,
.pmu_disable = x86_pmu_disable,
@@ -2302,6 +2315,7 @@ static struct pmu pmu = {
.event_idx = x86_pmu_event_idx,
.sched_task = x86_pmu_sched_task,
.task_ctx_size = sizeof(struct x86_perf_task_context),
+ .check_period = x86_pmu_check_period,
};
void arch_perf_update_userpage(struct perf_event *event,
diff --git a/arch/x86/events/intel/core.c b/arch/x86/events/intel/core.c
index daafb893449b..730978dff63f 100644
--- a/arch/x86/events/intel/core.c
+++ b/arch/x86/events/intel/core.c
@@ -3587,6 +3587,11 @@ static void intel_pmu_sched_task(struct perf_event_context *ctx,
intel_pmu_lbr_sched_task(ctx, sched_in);
}
+static int intel_pmu_check_period(struct perf_event *event, u64 value)
+{
+ return intel_pmu_has_bts_period(event, value) ? -EINVAL : 0;
+}
+
PMU_FORMAT_ATTR(offcore_rsp, "config1:0-63");
PMU_FORMAT_ATTR(ldlat, "config1:0-15");
@@ -3667,6 +3672,8 @@ static __initconst const struct x86_pmu core_pmu = {
.cpu_starting = intel_pmu_cpu_starting,
.cpu_dying = intel_pmu_cpu_dying,
.cpu_dead = intel_pmu_cpu_dead,
+
+ .check_period = intel_pmu_check_period,
};
static struct attribute *intel_pmu_attrs[];
@@ -3711,6 +3718,8 @@ static __initconst const struct x86_pmu intel_pmu = {
.guest_get_msrs = intel_guest_get_msrs,
.sched_task = intel_pmu_sched_task,
+
+ .check_period = intel_pmu_check_period,
};
static __init void intel_clovertown_quirk(void)
diff --git a/arch/x86/events/perf_event.h b/arch/x86/events/perf_event.h
index 78d7b7031bfc..d46fd6754d92 100644
--- a/arch/x86/events/perf_event.h
+++ b/arch/x86/events/perf_event.h
@@ -646,6 +646,11 @@ struct x86_pmu {
* Intel host/guest support (KVM)
*/
struct perf_guest_switch_msr *(*guest_get_msrs)(int *nr);
+
+ /*
+ * Check period value for PERF_EVENT_IOC_PERIOD ioctl.
+ */
+ int (*check_period) (struct perf_event *event, u64 period);
};
struct x86_perf_task_context {
@@ -857,7 +862,7 @@ static inline int amd_pmu_init(void)
#ifdef CONFIG_CPU_SUP_INTEL
-static inline bool intel_pmu_has_bts(struct perf_event *event)
+static inline bool intel_pmu_has_bts_period(struct perf_event *event, u64 period)
{
struct hw_perf_event *hwc = &event->hw;
unsigned int hw_event, bts_event;
@@ -868,7 +873,14 @@ static inline bool intel_pmu_has_bts(struct perf_event *event)
hw_event = hwc->config & INTEL_ARCH_EVENT_MASK;
bts_event = x86_pmu.event_map(PERF_COUNT_HW_BRANCH_INSTRUCTIONS);
- return hw_event == bts_event && hwc->sample_period == 1;
+ return hw_event == bts_event && period == 1;
+}
+
+static inline bool intel_pmu_has_bts(struct perf_event *event)
+{
+ struct hw_perf_event *hwc = &event->hw;
+
+ return intel_pmu_has_bts_period(event, hwc->sample_period);
}
int intel_pmu_save_and_restart(struct perf_event *event);
diff --git a/include/linux/perf_event.h b/include/linux/perf_event.h
index 1d5c551a5add..e1a051724f7e 100644
--- a/include/linux/perf_event.h
+++ b/include/linux/perf_event.h
@@ -447,6 +447,11 @@ struct pmu {
* Filter events for PMU-specific reasons.
*/
int (*filter_match) (struct perf_event *event); /* optional */
+
+ /*
+ * Check period value for PERF_EVENT_IOC_PERIOD ioctl.
+ */
+ int (*check_period) (struct perf_event *event, u64 value); /* optional */
};
enum perf_addr_filter_action_t {
diff --git a/kernel/events/core.c b/kernel/events/core.c
index e5ede6918050..26d6edab051a 100644
--- a/kernel/events/core.c
+++ b/kernel/events/core.c
@@ -4963,6 +4963,11 @@ static void __perf_event_period(struct perf_event *event,
}
}
+static int perf_event_check_period(struct perf_event *event, u64 value)
+{
+ return event->pmu->check_period(event, value);
+}
+
static int perf_event_period(struct perf_event *event, u64 __user *arg)
{
u64 value;
@@ -4979,6 +4984,9 @@ static int perf_event_period(struct perf_event *event, u64 __user *arg)
if (event->attr.freq && value > sysctl_perf_event_sample_rate)
return -EINVAL;
+ if (perf_event_check_period(event, value))
+ return -EINVAL;
+
event_function_call(event, __perf_event_period, &value);
return 0;
@@ -9391,6 +9399,11 @@ static int perf_pmu_nop_int(struct pmu *pmu)
return 0;
}
+static int perf_event_nop_int(struct perf_event *event, u64 value)
+{
+ return 0;
+}
+
static DEFINE_PER_CPU(unsigned int, nop_txn_flags);
static void perf_pmu_start_txn(struct pmu *pmu, unsigned int flags)
@@ -9691,6 +9704,9 @@ int perf_pmu_register(struct pmu *pmu, const char *name, int type)
pmu->pmu_disable = perf_pmu_nop_void;
}
+ if (!pmu->check_period)
+ pmu->check_period = perf_event_nop_int;
+
if (!pmu->event_idx)
pmu->event_idx = perf_event_idx_default;
diff --git a/kernel/events/ring_buffer.c b/kernel/events/ring_buffer.c
index 309ef5a64af5..5ab4fe3b1dcc 100644
--- a/kernel/events/ring_buffer.c
+++ b/kernel/events/ring_buffer.c
@@ -734,7 +734,7 @@ struct ring_buffer *rb_alloc(int nr_pages, long watermark, int cpu, int flags)
size = sizeof(struct ring_buffer);
size += nr_pages * sizeof(void *);
- if (order_base_2(size) >= MAX_ORDER)
+ if (order_base_2(size) >= PAGE_SHIFT+MAX_ORDER)
goto fail;
rb = kzalloc(size, GFP_KERNEL);