Commit b81d5e9d authored by Emil Tsalapatis's avatar Emil Tsalapatis Committed by Alexei Starovoitov
Browse files

selftests/bpf: add tests for arena kfuncs under lock 



Add selftests to ensure the verifier permits calling the arena
kfunc API while holding a lock.

Signed-off-by: default avatarEmil Tsalapatis <emil@etsalapatis.com>
Link: https://lore.kernel.org/r/20260106-arena-under-lock-v2-3-378e9eab3066@etsalapatis.com


Signed-off-by: default avatarAlexei Starovoitov <ast@kernel.org>
parent 39f77533

tools/testing/selftests/bpf/progs/verifier_arena.c

+38 −0
Original line number Diff line number Diff line
@@ -10,6 +10,8 @@ 
#include "bpf_experimental.h"

#include "bpf_arena_common.h"



#define private(name) SEC(".bss." #name) __hidden __attribute__((aligned(8)))



struct {

	__uint(type, BPF_MAP_TYPE_ARENA);

	__uint(map_flags, BPF_F_MMAPABLE);
@@ -439,4 +441,40 @@ int iter_maps3(struct bpf_iter__bpf_map *ctx) 
	return 0;

}



private(ARENA_TESTS) struct bpf_spin_lock arena_bpf_test_lock;



/* Use the arena kfunc API while under a BPF lock. */

SEC("syscall")

__success __retval(0)

int arena_kfuncs_under_bpf_lock(void *ctx)

{

#if defined(__BPF_FEATURE_ADDR_SPACE_CAST)

	char __arena *page;

	int ret;



	bpf_spin_lock(&arena_bpf_test_lock);



	/* Get a separate region of the arena. */

	page = arena_base(&arena);

	ret = bpf_arena_reserve_pages(&arena, page, 1);

	if (ret) {

		bpf_spin_unlock(&arena_bpf_test_lock);

		return 1;

	}



	bpf_arena_free_pages(&arena, page, 1);



	page = bpf_arena_alloc_pages(&arena, NULL, 1, NUMA_NO_NODE, 0);

	if (!page) {

		bpf_spin_unlock(&arena_bpf_test_lock);

		return 2;

	}



	bpf_arena_free_pages(&arena, page, 1);



	bpf_spin_unlock(&arena_bpf_test_lock);

#endif



	return 0;

}

char _license[] SEC("license") = "GPL";