samsung_sm8750/android_kernel_samsung_sm8750
1
0
Fork 0
Code Issues Pull Requests Actions Packages Projects Releases Wiki Activity

ANDROID: fix ABI-break in struct cgroup_root

Browse Source 
Fix the ABI issues introduced by commit dd9542ae7c ("cgroup: Make
operations on the cgroup root_list RCU safe"). Use _some_ of the bits
reserved in cgroup_root for the new root->rcu member. This new offset
restricts the usage of kfree_rcu() though, so this call has replaced
with call_rcu() instead. Update the stg file with this update:

type 'struct cgroup_root' changed
  member 'u8 android_backport_reserved1[28]' was removed
  member 'union { struct callback_head rcu; struct { u8 android_backport_reserved1[28]; }; union { }; }' was added

Bug: 379227997
Suggested-by: T.J. Mercier <tjmercier@google.com>
Change-Id: I3e76ca05ee6d68f7167bf487348f438cd2a00d5f
Signed-off-by: Carlos Llamas <cmllamas@google.com>
This commit is contained in:
Carlos Llamas
2024-11-22 19:11:28 +00:00
committed by Treehugger Robot
parent a3937e3e63
commit d66e9166bf
4 changed files with 41 additions and 6 deletions
Download Patch File Download Diff File Expand all files Collapse all files

32
android/abi_gki_aarch64.stg
View File

@@ -42307,6 +42307,10 @@ member {
id: 0x2ef635de
type_id: 0x34f6a768
}
member {
id: 0x2efe0273
type_id: 0x34d679de
}
member {
id: 0x2f1819a7
type_id: 0x334e168e
@@ -43924,6 +43928,11 @@ member {
type_id: 0x73b9d605
offset: 256
}
member {
id: 0x3f2a640d
type_id: 0x7387dd81
offset: 49472
}
member {
id: 0x3f2df7ff
type_id: 0x7399b0f3
@@ -49772,10 +49781,9 @@ member {
type_id: 0x92233392
}
member {
id: 0xb2e8fb7e
id: 0xb2e8f417
name: "android_backport_reserved1"
type_id: 0x1159eb36
offset: 49472
}
member {
id: 0x71aeb2cd
@@ -222059,6 +222067,14 @@ struct_union {
member_id: 0x39ff19b6
}
}
struct_union {
id: 0x34d679de
kind: STRUCT
definition {
bytesize: 32
member_id: 0xb2e8f417
}
}
struct_union {
id: 0x34ed11d4
kind: STRUCT
@@ -226230,6 +226246,16 @@ struct_union {
member_id: 0x92478c56
}
}
struct_union {
id: 0x7387dd81
kind: UNION
definition {
bytesize: 32
member_id: 0x95dac977
member_id: 0x2efe0273
member_id: 0x36752b74
}
}
struct_union {
id: 0x7399b0f3
kind: UNION
@@ -231813,7 +231839,7 @@ struct_union {
member_id: 0x2d2d08b0
member_id: 0xe8e1b772
member_id: 0x0de6d95b
member_id: 0xb2e8fb7e
member_id: 0x3f2a640d
}
}
struct_union {

4
android/abi_gki_aarch64.stg.allowed_breaks
View File

@@ -82,3 +82,7 @@ type 'enum ftrace_dump_mode' changed
1 variable symbol(s) removed
'struct tracepoint __tracepoint_android_vh_suitable_migration_target_bypass'
type 'struct cgroup_root' changed
member 'u8 android_backport_reserved1[28]' was removed
member 'union { struct callback_head rcu; struct { u8 android_backport_reserved1[28]; }; union { }; }' was added

4
include/linux/cgroup-defs.h
View File

@@ -575,7 +575,6 @@ struct cgroup_root {
/* A list running through the active hierarchies */
struct list_head root_list;
struct rcu_head rcu;
/* Hierarchy-specific flags */
unsigned int flags;
@@ -586,7 +585,8 @@ struct cgroup_root {
/* The name for this hierarchy - may be empty */
char name[MAX_CGROUP_ROOT_NAMELEN];
ANDROID_BACKPORT_RESERVE_ARRAY(1, CGROUP_SUBSYS_COUNT * sizeof(atomic_t));
ANDROID_BACKPORT_USE_ARRAY(1, CGROUP_SUBSYS_COUNT * sizeof(atomic_t),
struct rcu_head rcu);
};
/*

7
kernel/cgroup/cgroup.c
View File

@@ -1315,9 +1315,14 @@ static void cgroup_exit_root_id(struct cgroup_root *root)
idr_remove(&cgroup_hierarchy_idr, root->hierarchy_id);
}
static void __cgroup_free_root(struct rcu_head *rcu)
{
kfree(container_of(rcu, struct cgroup_root, rcu));
}
void cgroup_free_root(struct cgroup_root *root)
{
kfree_rcu(root, rcu);
call_rcu(&root->rcu, __cgroup_free_root);
}
static void cgroup_destroy_root(struct cgroup_root *root)