[PATCH] drm/amdgpu: Use flexible array member

[PATCH] drm/amdgpu: Use flexible array member

[Lijo Lazar]

Use flexible array member in ip discovery struct as recommended[1].

[1] https://www.kernel.org/doc/html/latest/process/deprecated.html#zero-length-and-one-element-arrays

Signed-off-by: Lijo Lazar <lijo.lazar@amd.com>
---
 drivers/gpu/drm/amd/amdgpu/amdgpu_discovery.c | 2 +-
 drivers/gpu/drm/amd/include/discovery.h       | 2 +-
 2 files changed, 2 insertions(+), 2 deletions(-)

diff --git a/drivers/gpu/drm/amd/amdgpu/amdgpu_discovery.c b/drivers/gpu/drm/amd/amdgpu/amdgpu_discovery.c
index 5a182288391b..b577fa1d7ecc 100644
--- a/drivers/gpu/drm/amd/amdgpu/amdgpu_discovery.c
+++ b/drivers/gpu/drm/amd/amdgpu/amdgpu_discovery.c
@@ -430,7 +430,7 @@ static void amdgpu_discovery_read_harvest_bit_per_ip(struct amdgpu_device *adev,
                                 }
                         }
 next_ip:
-			ip_offset += sizeof(*ip) + 4 * (ip->num_base_address - 1);
+			ip_offset += sizeof(*ip) + sizeof(uint32_t) * (ip->num_base_address);
 		}
 	}
 }
diff --git a/drivers/gpu/drm/amd/include/discovery.h b/drivers/gpu/drm/amd/include/discovery.h
index a486769b66c6..b25026c3ec96 100644
--- a/drivers/gpu/drm/amd/include/discovery.h
+++ b/drivers/gpu/drm/amd/include/discovery.h
@@ -93,7 +93,7 @@ typedef struct ip
 	uint8_t harvest : 4;      /* Harvest */
 	uint8_t reserved : 4;     /* Placeholder field */
 #endif
-	uint32_t base_address[1]; /* variable number of Addresses */
+	uint32_t base_address[]; /* variable number of Addresses */
 } ip;
 
 typedef struct die_header
-- 
2.25.1

Re: [PATCH] drm/amdgpu: Use flexible array member

[Christian König]

Am 08.04.22 um 06:02 schrieb Lijo Lazar:
> Use flexible array member in ip discovery struct as recommended[1].
>
> [1] https://www.kernel.org/doc/html/latest/process/deprecated.html#zero-length-and-one-element-arrays
>
> Signed-off-by: Lijo Lazar <lijo.lazar@amd.com>
> ---
>   drivers/gpu/drm/amd/amdgpu/amdgpu_discovery.c | 2 +-
>   drivers/gpu/drm/amd/include/discovery.h       | 2 +-
>   2 files changed, 2 insertions(+), 2 deletions(-)
>
> diff --git a/drivers/gpu/drm/amd/amdgpu/amdgpu_discovery.c b/drivers/gpu/drm/amd/amdgpu/amdgpu_discovery.c
> index 5a182288391b..b577fa1d7ecc 100644
> --- a/drivers/gpu/drm/amd/amdgpu/amdgpu_discovery.c
> +++ b/drivers/gpu/drm/amd/amdgpu/amdgpu_discovery.c
> @@ -430,7 +430,7 @@ static void amdgpu_discovery_read_harvest_bit_per_ip(struct amdgpu_device *adev,
>                                   }
>                           }
>   next_ip:
> -			ip_offset += sizeof(*ip) + 4 * (ip->num_base_address - 1);
> +			ip_offset += sizeof(*ip) + sizeof(uint32_t) * (ip->num_base_address);

Please use the struct_size() macro for this, apart from that looks good 
to me.

Thanks,
Christian.

>   		}
>   	}
>   }
> diff --git a/drivers/gpu/drm/amd/include/discovery.h b/drivers/gpu/drm/amd/include/discovery.h
> index a486769b66c6..b25026c3ec96 100644
> --- a/drivers/gpu/drm/amd/include/discovery.h
> +++ b/drivers/gpu/drm/amd/include/discovery.h
> @@ -93,7 +93,7 @@ typedef struct ip
>   	uint8_t harvest : 4;      /* Harvest */
>   	uint8_t reserved : 4;     /* Placeholder field */
>   #endif
> -	uint32_t base_address[1]; /* variable number of Addresses */
> +	uint32_t base_address[]; /* variable number of Addresses */
>   } ip;
>   
>   typedef struct die_header