diff options
| author | Kees Cook <keescook@chromium.org> | 2018-06-29 20:45:36 +0200 |
|---|---|---|
| committer | Will Deacon <will.deacon@arm.com> | 2018-07-02 13:50:03 +0200 |
| commit | 1201a5a25cf0f7d8019d106a81c64f3a7397d17c (patch) | |
| tree | 25b5c6edd320fad677a13c3b33c46718ab253685 /drivers/perf | |
| parent | Linux 4.18-rc1 (diff) | |
| download | linux-1201a5a25cf0f7d8019d106a81c64f3a7397d17c.tar.xz linux-1201a5a25cf0f7d8019d106a81c64f3a7397d17c.zip | |
perf/arm-cci: Remove VLA usage
In the quest to remove all stack VLA usage from the kernel[1], this
removes the VLA in favor of a maximum size and adds a sanity check
at registration time. The sizes are all explicitly enumerated already,
so this just collects them into macros.
[1] https://lkml.kernel.org/r/CA+55aFzCG-zNmZwX4A2FQpadafLfEzK6CC=qPXydAacU1RqZWA@mail.gmail.com
Signed-off-by: Kees Cook <keescook@chromium.org>
Signed-off-by: Will Deacon <will.deacon@arm.com>
Diffstat (limited to 'drivers/perf')
| -rw-r--r-- | drivers/perf/arm-cci.c | 38 |
1 files changed, 26 insertions, 12 deletions
diff --git a/drivers/perf/arm-cci.c b/drivers/perf/arm-cci.c index 0d09d8e669cd..1bfeb160c5b1 100644 --- a/drivers/perf/arm-cci.c +++ b/drivers/perf/arm-cci.c @@ -53,6 +53,16 @@ enum { CCI_IF_MAX, }; +#define NUM_HW_CNTRS_CII_4XX 4 +#define NUM_HW_CNTRS_CII_5XX 8 +#define NUM_HW_CNTRS_MAX NUM_HW_CNTRS_CII_5XX + +#define FIXED_HW_CNTRS_CII_4XX 1 +#define FIXED_HW_CNTRS_CII_5XX 0 +#define FIXED_HW_CNTRS_MAX FIXED_HW_CNTRS_CII_4XX + +#define HW_CNTRS_MAX (NUM_HW_CNTRS_MAX + FIXED_HW_CNTRS_MAX) + struct event_range { u32 min; u32 max; @@ -633,8 +643,7 @@ static void cci_pmu_sync_counters(struct cci_pmu *cci_pmu) { int i; struct cci_pmu_hw_events *cci_hw = &cci_pmu->hw_events; - - DECLARE_BITMAP(mask, cci_pmu->num_cntrs); + DECLARE_BITMAP(mask, HW_CNTRS_MAX); bitmap_zero(mask, cci_pmu->num_cntrs); for_each_set_bit(i, cci_pmu->hw_events.used_mask, cci_pmu->num_cntrs) { @@ -940,7 +949,7 @@ static void pmu_write_counters(struct cci_pmu *cci_pmu, unsigned long *mask) static void cci5xx_pmu_write_counters(struct cci_pmu *cci_pmu, unsigned long *mask) { int i; - DECLARE_BITMAP(saved_mask, cci_pmu->num_cntrs); + DECLARE_BITMAP(saved_mask, HW_CNTRS_MAX); bitmap_zero(saved_mask, cci_pmu->num_cntrs); pmu_save_counters(cci_pmu, saved_mask); @@ -1245,7 +1254,7 @@ static int validate_group(struct perf_event *event) { struct perf_event *sibling, *leader = event->group_leader; struct cci_pmu *cci_pmu = to_cci_pmu(event->pmu); - unsigned long mask[BITS_TO_LONGS(cci_pmu->num_cntrs)]; + unsigned long mask[BITS_TO_LONGS(HW_CNTRS_MAX)]; struct cci_pmu_hw_events fake_pmu = { /* * Initialise the fake PMU. We only need to populate the @@ -1403,6 +1412,11 @@ static int cci_pmu_init(struct cci_pmu *cci_pmu, struct platform_device *pdev) char *name = model->name; u32 num_cntrs; + if (WARN_ON(model->num_hw_cntrs > NUM_HW_CNTRS_MAX)) + return -EINVAL; + if (WARN_ON(model->fixed_hw_cntrs > FIXED_HW_CNTRS_MAX)) + return -EINVAL; + pmu_event_attr_group.attrs = model->event_attrs; pmu_format_attr_group.attrs = model->format_attrs; @@ -1455,8 +1469,8 @@ static __maybe_unused struct cci_pmu_model cci_pmu_models[] = { #ifdef CONFIG_ARM_CCI400_PMU [CCI400_R0] = { .name = "CCI_400", - .fixed_hw_cntrs = 1, /* Cycle counter */ - .num_hw_cntrs = 4, + .fixed_hw_cntrs = FIXED_HW_CNTRS_CII_4XX, /* Cycle counter */ + .num_hw_cntrs = NUM_HW_CNTRS_CII_4XX, .cntr_size = SZ_4K, .format_attrs = cci400_pmu_format_attrs, .event_attrs = cci400_r0_pmu_event_attrs, @@ -1475,8 +1489,8 @@ static __maybe_unused struct cci_pmu_model cci_pmu_models[] = { }, [CCI400_R1] = { .name = "CCI_400_r1", - .fixed_hw_cntrs = 1, /* Cycle counter */ - .num_hw_cntrs = 4, + .fixed_hw_cntrs = FIXED_HW_CNTRS_CII_4XX, /* Cycle counter */ + .num_hw_cntrs = NUM_HW_CNTRS_CII_4XX, .cntr_size = SZ_4K, .format_attrs = cci400_pmu_format_attrs, .event_attrs = cci400_r1_pmu_event_attrs, @@ -1497,8 +1511,8 @@ static __maybe_unused struct cci_pmu_model cci_pmu_models[] = { #ifdef CONFIG_ARM_CCI5xx_PMU [CCI500_R0] = { .name = "CCI_500", - .fixed_hw_cntrs = 0, - .num_hw_cntrs = 8, + .fixed_hw_cntrs = FIXED_HW_CNTRS_CII_5XX, + .num_hw_cntrs = NUM_HW_CNTRS_CII_5XX, .cntr_size = SZ_64K, .format_attrs = cci5xx_pmu_format_attrs, .event_attrs = cci5xx_pmu_event_attrs, @@ -1521,8 +1535,8 @@ static __maybe_unused struct cci_pmu_model cci_pmu_models[] = { }, [CCI550_R0] = { .name = "CCI_550", - .fixed_hw_cntrs = 0, - .num_hw_cntrs = 8, + .fixed_hw_cntrs = FIXED_HW_CNTRS_CII_5XX, + .num_hw_cntrs = NUM_HW_CNTRS_CII_5XX, .cntr_size = SZ_64K, .format_attrs = cci5xx_pmu_format_attrs, .event_attrs = cci5xx_pmu_event_attrs, |