Re: [PATCH-for-5.0] gdbstub: Do not use memset() on GByteArray

["Alex Bennée" <alex.bennee@linaro.org>]

Philippe Mathieu-Daudé <philmd@redhat.com> writes:

> Introduce gdb_get_zeroes() to fill a GByteArray with zeroes.
>
> Fixes: a010bdbe719 ("extend GByteArray to read register helpers")
> Signed-off-by: Philippe Mathieu-Daudé <philmd@redhat.com>

Queued to for-5.0/more-random-fixes with Peter's alternative.

> ---
>  include/exec/gdbstub.h  | 9 +++++++++
>  target/arm/gdbstub.c    | 3 +--
>  target/xtensa/gdbstub.c | 6 ++----
>  3 files changed, 12 insertions(+), 6 deletions(-)
>
> diff --git a/include/exec/gdbstub.h b/include/exec/gdbstub.h
> index 30b909ebd2..b52d9933ee 100644
> --- a/include/exec/gdbstub.h
> +++ b/include/exec/gdbstub.h
> @@ -125,6 +125,15 @@ static inline int gdb_get_reg128(GByteArray *buf, uint64_t val_hi,
>      return 16;
>  }
>  
> +static inline int gdb_get_zeroes(GByteArray *array, size_t len)
> +{
> +    for (size_t i = 0; i < len; i++) {
> +        gdb_get_reg8(array, '\0');
> +    }
> +
> +    return len;
> +}
> +
>  /**
>   * gdb_get_reg_ptr: get pointer to start of last element
>   * @len: length of element
> diff --git a/target/arm/gdbstub.c b/target/arm/gdbstub.c
> index 8efc535f2a..063551df23 100644
> --- a/target/arm/gdbstub.c
> +++ b/target/arm/gdbstub.c
> @@ -47,8 +47,7 @@ int arm_cpu_gdb_read_register(CPUState *cs, GByteArray *mem_buf, int n)
>          if (gdb_has_xml) {
>              return 0;
>          }
> -        memset(mem_buf, 0, 12);
> -        return 12;
> +        return gdb_get_zeroes(mem_buf, 12);
>      }
>      switch (n) {
>      case 24:
> diff --git a/target/xtensa/gdbstub.c b/target/xtensa/gdbstub.c
> index 0ee3feabe5..4d43f1340a 100644
> --- a/target/xtensa/gdbstub.c
> +++ b/target/xtensa/gdbstub.c
> @@ -105,8 +105,7 @@ int xtensa_cpu_gdb_read_register(CPUState *cs, GByteArray *mem_buf, int n)
>          default:
>              qemu_log_mask(LOG_UNIMP, "%s from reg %d of unsupported size %d\n",
>                            __func__, n, reg->size);
> -            memset(mem_buf, 0, reg->size);
> -            return reg->size;
> +            return gdb_get_zeroes(mem_buf, reg->size);
>          }
>  
>      case xtRegisterTypeWindow: /*a*/
> @@ -115,8 +114,7 @@ int xtensa_cpu_gdb_read_register(CPUState *cs, GByteArray *mem_buf, int n)
>      default:
>          qemu_log_mask(LOG_UNIMP, "%s from reg %d of unsupported type %d\n",
>                        __func__, n, reg->type);
> -        memset(mem_buf, 0, reg->size);
> -        return reg->size;
> +        return gdb_get_zeroes(mem_buf, reg->size);
>      }
>  }


-- 
Alex Bennée