From 2233228b65291f8e9b04ee8be52bd2f694e12889 Mon Sep 17 00:00:00 2001 From: Yury Norov Date: Fri, 11 Sep 2026 18:14:42 -0400 Subject: [PATCH] idr: assert static storage for DEFINE_IDA() 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 Signed-off-by: Andrew Morton Cc: Alice Ryhl Cc: Andrew Ballance Cc: Christopher Li Cc: Liam R. Howlett Cc: Matthew Wilcox (Oracle) --- include/linux/idr.h | 5 ++++- tools/testing/radix-tree/idr-test.c | 20 +++++++++++++++----- 2 files changed, 19 insertions(+), 6 deletions(-) diff --git a/include/linux/idr.h b/include/linux/idr.h index 789e23e67444..e2a4b6298511 100644 --- a/include/linux/idr.h +++ b/include/linux/idr.h @@ -16,6 +16,7 @@ #include #include #include +#include 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); diff --git a/tools/testing/radix-tree/idr-test.c b/tools/testing/radix-tree/idr-test.c index 945144e98507..6fcba5b5870b 100644 --- a/tools/testing/radix-tree/idr-test.c +++ b/tools/testing/radix-tree/idr-test.c @@ -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");