[PATCH 4/4] powerpc/ps3: use put_device() on device_register() failure in ps3_system_bus_device_register
Tarun Sahu
tarunsahu at google.com
Mon Aug 10 09:28:14 PDT 2026
When device_register() fails, calling put_device() ensures that the
device reference count drops to 0, which invokes the release callback
ps3_system_bus_release_device() to cleanly free the device and its
associated driver core resources.
Signed-off-by: Tarun Sahu <tarunsahu at google.com>
---
arch/powerpc/platforms/ps3/device-init.c | 83 ++++++++++++++----------
arch/powerpc/platforms/ps3/system-bus.c | 2 +
2 files changed, 52 insertions(+), 33 deletions(-)
diff --git a/arch/powerpc/platforms/ps3/device-init.c b/arch/powerpc/platforms/ps3/device-init.c
index 9109c218a060..8d0c77db1764 100644
--- a/arch/powerpc/platforms/ps3/device-init.c
+++ b/arch/powerpc/platforms/ps3/device-init.c
@@ -90,14 +90,12 @@ static int __init ps3_register_lpm_devices(void)
if (result) {
pr_debug("%s:%d ps3_system_bus_device_register failed\n",
__func__, __LINE__);
- goto fail_register;
+ return result;
}
pr_debug(" <- %s:%d\n", __func__, __LINE__);
return 0;
-
-fail_register:
fail_rights:
fail_read_repo:
kfree(dev);
@@ -121,6 +119,12 @@ static int __init ps3_setup_gelic_device(
struct ps3_dma_region d_region;
} *p;
+ /*
+ * ps3_system_bus_release_device() calls kfree(&p->dev).
+ * dev must be at offset 0 so kfree() frees outer p.
+ */
+ BUILD_BUG_ON(offsetof(struct layout, dev) != 0);
+
pr_debug(" -> %s:%d\n", __func__, __LINE__);
BUG_ON(repo->bus_type != PS3_BUS_TYPE_SB);
@@ -164,13 +168,12 @@ static int __init ps3_setup_gelic_device(
if (result) {
pr_debug("%s:%d ps3_system_bus_device_register failed\n",
__func__, __LINE__);
- goto fail_device_register;
+ return result;
}
pr_debug(" <- %s:%d\n", __func__, __LINE__);
return result;
-fail_device_register:
fail_dma_init:
fail_find_interrupt:
kfree(p);
@@ -192,6 +195,12 @@ static int __init ps3_setup_uhc_device(
u64 bus_addr;
u64 len;
+ /*
+ * ps3_system_bus_release_device() calls kfree(&p->dev).
+ * dev must be at offset 0 so kfree() frees outer p.
+ */
+ BUILD_BUG_ON(offsetof(struct layout, dev) != 0);
+
pr_debug(" -> %s:%d\n", __func__, __LINE__);
BUG_ON(repo->bus_type != PS3_BUS_TYPE_SB);
@@ -252,13 +261,12 @@ static int __init ps3_setup_uhc_device(
if (result) {
pr_debug("%s:%d ps3_system_bus_device_register failed\n",
__func__, __LINE__);
- goto fail_device_register;
+ return result;
}
pr_debug(" <- %s:%d\n", __func__, __LINE__);
return result;
-fail_device_register:
fail_mmio_init:
fail_dma_init:
fail_find_reg:
@@ -291,6 +299,12 @@ static int __init ps3_setup_vuart_device(enum ps3_match_id match_id,
struct ps3_system_bus_device dev;
} *p;
+ /*
+ * ps3_system_bus_release_device() calls kfree(&p->dev).
+ * dev must be at offset 0 so kfree() frees outer p.
+ */
+ BUILD_BUG_ON(offsetof(struct layout, dev) != 0);
+
pr_debug(" -> %s:%d: match_id %u, port %u\n", __func__, __LINE__,
match_id, port_number);
@@ -308,15 +322,10 @@ static int __init ps3_setup_vuart_device(enum ps3_match_id match_id,
if (result) {
pr_debug("%s:%d ps3_system_bus_device_register failed\n",
__func__, __LINE__);
- goto fail_device_register;
+ return result;
}
pr_debug(" <- %s:%d\n", __func__, __LINE__);
return 0;
-
-fail_device_register:
- kfree(p);
- pr_debug(" <- %s:%d fail\n", __func__, __LINE__);
- return result;
}
static int ps3_setup_storage_dev(const struct ps3_repository_device *repo,
@@ -327,6 +336,12 @@ static int ps3_setup_storage_dev(const struct ps3_repository_device *repo,
u64 port, blk_size, num_blocks;
unsigned int num_regions, i;
+ /*
+ * ps3_system_bus_release_device() calls kfree(&p->sbd).
+ * sbd must be at offset 0 so kfree() frees outer p.
+ */
+ BUILD_BUG_ON(offsetof(struct ps3_storage_device, sbd) != 0);
+
pr_debug(" -> %s:%u: match_id %u\n", __func__, __LINE__, match_id);
result = ps3_repository_read_stor_dev_info(repo->bus_index,
@@ -395,13 +410,12 @@ static int ps3_setup_storage_dev(const struct ps3_repository_device *repo,
if (result) {
pr_debug("%s:%u ps3_system_bus_device_register failed\n",
__func__, __LINE__);
- goto fail_device_register;
+ return result;
}
pr_debug(" <- %s:%u\n", __func__, __LINE__);
return 0;
-fail_device_register:
fail_read_region:
fail_find_interrupt:
kfree(p);
@@ -445,6 +459,12 @@ static int __init ps3_register_sound_devices(void)
struct ps3_mmio_region m_region;
} *p;
+ /*
+ * ps3_system_bus_release_device() calls kfree(&p->dev).
+ * dev must be at offset 0 so kfree() frees outer p.
+ */
+ BUILD_BUG_ON(offsetof(struct layout, dev) != 0);
+
pr_debug(" -> %s:%d\n", __func__, __LINE__);
p = kzalloc_obj(*p);
@@ -461,15 +481,10 @@ static int __init ps3_register_sound_devices(void)
if (result) {
pr_debug("%s:%d ps3_system_bus_device_register failed\n",
__func__, __LINE__);
- goto fail_device_register;
+ return result;
}
pr_debug(" <- %s:%d\n", __func__, __LINE__);
return 0;
-
-fail_device_register:
- kfree(p);
- pr_debug(" <- %s:%d failed\n", __func__, __LINE__);
- return result;
}
static int __init ps3_register_graphics_devices(void)
@@ -479,6 +494,12 @@ static int __init ps3_register_graphics_devices(void)
struct ps3_system_bus_device dev;
} *p;
+ /*
+ * ps3_system_bus_release_device() calls kfree(&p->dev).
+ * dev must be at offset 0 so kfree() frees outer p.
+ */
+ BUILD_BUG_ON(offsetof(struct layout, dev) != 0);
+
pr_debug(" -> %s:%d\n", __func__, __LINE__);
p = kzalloc_obj(struct layout);
@@ -495,16 +516,11 @@ static int __init ps3_register_graphics_devices(void)
if (result) {
pr_debug("%s:%d ps3_system_bus_device_register failed\n",
__func__, __LINE__);
- goto fail_device_register;
+ return result;
}
pr_debug(" <- %s:%d\n", __func__, __LINE__);
return 0;
-
-fail_device_register:
- kfree(p);
- pr_debug(" <- %s:%d failed\n", __func__, __LINE__);
- return result;
}
static int __init ps3_register_ramdisk_device(void)
@@ -514,6 +530,12 @@ static int __init ps3_register_ramdisk_device(void)
struct ps3_system_bus_device dev;
} *p;
+ /*
+ * ps3_system_bus_release_device() calls kfree(&p->dev).
+ * dev must be at offset 0 so kfree() frees outer p.
+ */
+ BUILD_BUG_ON(offsetof(struct layout, dev) != 0);
+
pr_debug(" -> %s:%d\n", __func__, __LINE__);
p = kzalloc_obj(struct layout);
@@ -530,16 +552,11 @@ static int __init ps3_register_ramdisk_device(void)
if (result) {
pr_debug("%s:%d ps3_system_bus_device_register failed\n",
__func__, __LINE__);
- goto fail_device_register;
+ return result;
}
pr_debug(" <- %s:%d\n", __func__, __LINE__);
return 0;
-
-fail_device_register:
- kfree(p);
- pr_debug(" <- %s:%d failed\n", __func__, __LINE__);
- return result;
}
/**
diff --git a/arch/powerpc/platforms/ps3/system-bus.c b/arch/powerpc/platforms/ps3/system-bus.c
index 0537a678a32f..0918c74d3e19 100644
--- a/arch/powerpc/platforms/ps3/system-bus.c
+++ b/arch/powerpc/platforms/ps3/system-bus.c
@@ -774,6 +774,8 @@ int ps3_system_bus_device_register(struct ps3_system_bus_device *dev)
pr_debug("%s:%d add %s\n", __func__, __LINE__, dev_name(&dev->core));
result = device_register(&dev->core);
+ if (result)
+ put_device(&dev->core);
return result;
}
--
2.55.0.679.g6767b8d81c-goog
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