github-mirror/linux
1
0
Fork 0
mirror of https://github.com/torvalds/linux.git synced 2026-11-07 06:17:02 +01:00
Code Issues Actions Packages Projects Releases Wiki Activity Graph

idr: assert static storage for DEFINE_IDA()

Browse Source 
DEFINE_IDA() uses IDA_INIT(), which initializes the embedded XArray lock
with a static spinlock initializer.  For an automatic local IDA, lockdep
cannot use the lock address as a persistent class key and reports "INFO:
trying to register non-static key" before disabling itself.

Apply ASSERT_STATIC_STORAGE() to DEFINE_IDA() so that this misuse is
rejected at compile time.  For example:

  void example(void)
  {
          DEFINE_IDA(ida);
          ida_destroy(&ida);
  }

GCC reports:

  error: initializer element is not constant
    name##_storage_check = &(name)
                           ^
  note: in expansion of macro 'ASSERT_STATIC_STORAGE'
    ASSERT_STATIC_STORAGE(name)
  note: in expansion of macro 'DEFINE_IDA'
    DEFINE_IDA(ida);

File-scope definitions and static DEFINE_IDA() within a function remain
valid.  Automatic local IDAs must instead be initialized with ida_init(). 
Direct uses of IDA_INIT() are not covered by this declaration check.

Convert the five automatic local IDAs in the userspace radix-tree tests to
ida_init() so they satisfy the new requirement.

Validated file-scope and static local definitions with a kernel object
build, and confirmed that an automatic local definition fails to compile.

Link: https://lore.kernel.org/20260911221444.1523311-3-ynorov@nvidia.com
Signed-off-by: Yury Norov <ynorov@nvidia.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Cc: Alice Ryhl <aliceryhl@google.com>
Cc: Andrew Ballance <andrewjballance@gmail.com>
Cc: Christopher Li <sparse@chrisli.org>
Cc: Liam R. Howlett <liam@infradead.org>
Cc: Matthew Wilcox (Oracle) <willy@infradead.org>
This commit is contained in:
Yury Norov 2026-09-11 18:14:42 -04:00 committed by Andrew Morton
parent c3f25ea704
commit 2233228b65
2 changed files with 19 additions and 6 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

5
include/linux/idr.h
View File

@ -16,6 +16,7 @@
#include <linux/gfp.h>
#include <linux/percpu.h>
#include <linux/cleanup.h>
#include <linux/compiler.h>
struct idr {
struct radix_tree_root idr_rt;
@ -269,7 +270,9 @@ struct ida {
#define IDA_INIT(name) { \
.xa = XARRAY_INIT(name, IDA_INIT_FLAGS) \
}
#define DEFINE_IDA(name) struct ida name = IDA_INIT(name)
#define DEFINE_IDA(name) \
struct ida name = IDA_INIT(name); \
ASSERT_STATIC_STORAGE(name)
int ida_alloc_range(struct ida *, unsigned int min, unsigned int max, gfp_t);
void ida_free(struct ida *, unsigned int id);

20
tools/testing/radix-tree/idr-test.c
View File

@ -460,9 +460,11 @@ void ida_dump(struct ida *);
*/
void ida_check_nomem(void)
{
DEFINE_IDA(ida);
struct ida ida;
int id;
ida_init(&ida);
id = ida_alloc_min(&ida, 256, GFP_NOWAIT);
IDA_BUG_ON(&ida, id != -ENOMEM);
id = ida_alloc_min(&ida, 1UL << 30, GFP_NOWAIT);
@ -475,9 +477,11 @@ void ida_check_nomem(void)
*/
void ida_check_conv_user(void)
{
DEFINE_IDA(ida);
struct ida ida;
unsigned long i;
ida_init(&ida);
for (i = 0; i < 1000000; i++) {
int id = ida_alloc(&ida, GFP_NOWAIT);
if (id == -ENOMEM) {
@ -496,11 +500,13 @@ void ida_check_conv_user(void)
void ida_check_random(void)
{
DEFINE_IDA(ida);
struct ida ida;
DECLARE_BITMAP(bitmap, 2048);
unsigned int i;
time_t s = time(NULL);
ida_init(&ida);
repeat:
memset(bitmap, 0, sizeof(bitmap));
for (i = 0; i < 100000; i++) {
@ -522,9 +528,11 @@ void ida_check_random(void)
void ida_alloc_free_test(void)
{
DEFINE_IDA(ida);
struct ida ida;
unsigned long i;
ida_init(&ida);
for (i = 0; i < 10000; i++)
assert(ida_alloc_max(&ida, 20000, GFP_KERNEL) == i);
assert(ida_alloc_range(&ida, 5, 30, GFP_KERNEL) < 0);
@ -576,10 +584,12 @@ static void *ida_leak_fn(void *arg)
void ida_thread_tests(void)
{
DEFINE_IDA(ida);
struct ida ida;
pthread_t threads[20];
int i;
ida_init(&ida);
for (i = 0; i < ARRAY_SIZE(threads); i++)
if (pthread_create(&threads[i], NULL, ida_random_fn, NULL)) {
perror("creating ida thread");