From 42fcc7ba284c80cdc6790c20c4436b923bd8a9e1 Mon Sep 17 00:00:00 2001
From: Lijo Lazar <lijo.lazar@amd.com>
Date: Fri, 8 Apr 2022 09:11:04 +0530
Subject: drm/amdgpu: Use flexible array member
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Git-commit: 73bce7a423c3bb7c3441177aca868ff5f2cf93fa
Patch-mainline: v5.19-rc1
References: jsc#PED-1166 jsc#PED-1168 jsc#PED-1170 jsc#PED-1218 jsc#PED-1220 jsc#PED-1222 jsc#PED-1223 jsc#PED-1225

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

v2: squash in struct_size fixes

Signed-off-by: Lijo Lazar <lijo.lazar@amd.com>
Reviewed-by: Christian König <christian.koenig@amd.com>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>
Acked-by: Patrik Jakobsson <pjakobsson@suse.de>
---
 drivers/gpu/drm/amd/amdgpu/amdgpu_discovery.c | 8 ++++----
 drivers/gpu/drm/amd/include/discovery.h       | 2 +-
 2 files changed, 5 insertions(+), 5 deletions(-)

diff --git a/drivers/gpu/drm/amd/amdgpu/amdgpu_discovery.c b/drivers/gpu/drm/amd/amdgpu/amdgpu_discovery.c
index 5a182288391b..aaf2fc6b1a82 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 += struct_size(ip, base_address, ip->num_base_address);
 		}
 	}
 }
@@ -798,7 +798,7 @@ static int amdgpu_discovery_sysfs_ips(struct amdgpu_device *adev,
 			res = kobject_add(&ip_hw_instance->kobj, NULL,
 					  "%d", ip_hw_instance->num_instance);
 next_ip:
-			ip_offset += sizeof(*ip) + 4 * (ip->num_base_address - 1);
+			ip_offset += struct_size(ip, base_address, ip->num_base_address);
 		}
 	}
 
@@ -1063,7 +1063,7 @@ int amdgpu_discovery_reg_base_init(struct amdgpu_device *adev)
 			}
 
 next_ip:
-			ip_offset += sizeof(*ip) + 4 * (ip->num_base_address - 1);
+			ip_offset += struct_size(ip, base_address, ip->num_base_address);
 		}
 	}
 
@@ -1113,7 +1113,7 @@ int amdgpu_discovery_get_ip_version(struct amdgpu_device *adev, int hw_id, int n
 					*revision = ip->revision;
 				return 0;
 			}
-			ip_offset += sizeof(*ip) + 4 * (ip->num_base_address - 1);
+			ip_offset += struct_size(ip, base_address, 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
-- 
2.38.1