[PATCH 1/2] lib: utils/fdt: Remove redundant PMU property length checks

[Anup Patel]

On Fri, Feb 14, 2025 at 4:20 AM Samuel Holland
<samuel.holland at sifive.com> wrote:
>
> If a property value is too small, len will be zero after the division
> on the next line, so the property will be ignored. This is the same
> behavior as when the length check fails. Furthermore, the first two
> length checks were already ineffectual, because each item in those
> arrays is 12 bytes long, not 8.
>
> Signed-off-by: Samuel Holland <samuel.holland at sifive.com>

LGTM.

Reviewed-by: Anup Patel <anup at brainfault.org>

Applied this patch to the riscv/opensbi repo.

Thanks,
Anup

> ---
>
>  lib/utils/fdt/fdt_pmu.c | 6 +++---
>  1 file changed, 3 insertions(+), 3 deletions(-)
>
> diff --git a/lib/utils/fdt/fdt_pmu.c b/lib/utils/fdt/fdt_pmu.c
> index 64de569e..22760603 100644
> --- a/lib/utils/fdt/fdt_pmu.c
> +++ b/lib/utils/fdt/fdt_pmu.c
> @@ -74,7 +74,7 @@ int fdt_pmu_setup(const void *fdt)
>
>         event_ctr_map = fdt_getprop(fdt, pmu_offset,
>                                     "riscv,event-to-mhpmcounters", &len);
> -       if (event_ctr_map && len >= 8) {
> +       if (event_ctr_map) {
>                 len = len / (sizeof(u32) * 3);
>                 for (i = 0; i < len; i++) {
>                         event_idx_start = fdt32_to_cpu(event_ctr_map[3 * i]);
> @@ -89,7 +89,7 @@ int fdt_pmu_setup(const void *fdt)
>
>         event_val = fdt_getprop(fdt, pmu_offset,
>                                 "riscv,event-to-mhpmevent", &len);
> -       if (event_val && len >= 8) {
> +       if (event_val) {
>                 len = len / (sizeof(u32) * 3);
>                 for (i = 0; i < len; i++) {
>                         event = &fdt_pmu_evt_select[hw_event_count];
> @@ -103,7 +103,7 @@ int fdt_pmu_setup(const void *fdt)
>
>         event_val = fdt_getprop(fdt, pmu_offset,
>                                 "riscv,raw-event-to-mhpmcounters", &len);
> -       if (event_val && len >= 20) {
> +       if (event_val) {
>                 len = len / (sizeof(u32) * 5);
>                 for (i = 0; i < len; i++) {
>                         raw_selector = fdt32_to_cpu(event_val[5 * i]);
> --
> 2.47.0
>
>
> --
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