diff mbox series

[bpf-next,v2,2/2] selftests/bpf: Add a local kptr test with no special fields

Message ID 20230824063422.203097-1-yonghong.song@linux.dev (mailing list archive)
State Accepted
Commit 001fedacc907d641f7cfb89eb19c5d0535998662
Delegated to: BPF
Headers show
Series [bpf-next,v2,1/2] bpf: Remove a WARN_ON_ONCE warning related to local kptr | expand

Checks

Context Check Description
bpf/vmtest-bpf-next-PR success PR summary
bpf/vmtest-bpf-next-VM_Test-3 success Logs for build for x86_64 with gcc
bpf/vmtest-bpf-next-VM_Test-5 success Logs for set-matrix
bpf/vmtest-bpf-next-VM_Test-4 success Logs for build for x86_64 with llvm-16
bpf/vmtest-bpf-next-VM_Test-0 success Logs for ShellCheck
bpf/vmtest-bpf-next-VM_Test-1 success Logs for build for aarch64 with gcc
netdev/series_format success Single patches do not need cover letters
netdev/tree_selection success Clearly marked for bpf-next
netdev/fixes_present success Fixes tag not required for -next series
netdev/header_inline success No static functions without inline keyword in header files
netdev/build_32bit success Errors and warnings before: 9 this patch: 9
netdev/cc_maintainers warning 13 maintainers not CCed: void@manifault.com davemarchevsky@fb.com kpsingh@kernel.org martin.lau@linux.dev memxor@gmail.com john.fastabend@gmail.com sdf@google.com shuah@kernel.org song@kernel.org mykolal@fb.com linux-kselftest@vger.kernel.org jolsa@kernel.org haoluo@google.com
netdev/build_clang success Errors and warnings before: 9 this patch: 9
netdev/verify_signedoff success Signed-off-by tag matches author and committer
netdev/deprecated_api success None detected
netdev/check_selftest success No net selftest shell script
netdev/verify_fixes success No Fixes tag
netdev/build_allmodconfig_warn success Errors and warnings before: 9 this patch: 9
netdev/checkpatch warning CHECK: spaces preferred around that '*' (ctx:WxV) WARNING: line length of 86 exceeds 80 columns
netdev/kdoc success Errors and warnings before: 0 this patch: 0
netdev/source_inline success Was 0 now: 0
bpf/vmtest-bpf-next-VM_Test-2 success Logs for build for s390x with gcc
bpf/vmtest-bpf-next-VM_Test-22 success Logs for test_progs_parallel on x86_64 with gcc
bpf/vmtest-bpf-next-VM_Test-20 success Logs for test_progs_no_alu32_parallel on x86_64 with llvm-16
bpf/vmtest-bpf-next-VM_Test-6 success Logs for test_maps on aarch64 with gcc
bpf/vmtest-bpf-next-VM_Test-13 success Logs for test_progs on x86_64 with llvm-16
bpf/vmtest-bpf-next-VM_Test-26 success Logs for test_verifier on x86_64 with gcc
bpf/vmtest-bpf-next-VM_Test-19 success Logs for test_progs_no_alu32_parallel on x86_64 with gcc
bpf/vmtest-bpf-next-VM_Test-18 success Logs for test_progs_no_alu32_parallel on aarch64 with gcc
bpf/vmtest-bpf-next-VM_Test-9 success Logs for test_maps on x86_64 with llvm-16
bpf/vmtest-bpf-next-VM_Test-27 success Logs for test_verifier on x86_64 with llvm-16
bpf/vmtest-bpf-next-VM_Test-17 success Logs for test_progs_no_alu32 on x86_64 with llvm-16
bpf/vmtest-bpf-next-VM_Test-12 success Logs for test_progs on x86_64 with gcc
bpf/vmtest-bpf-next-VM_Test-24 success Logs for test_verifier on aarch64 with gcc
bpf/vmtest-bpf-next-VM_Test-28 success Logs for veristat
bpf/vmtest-bpf-next-VM_Test-8 success Logs for test_maps on x86_64 with gcc
bpf/vmtest-bpf-next-VM_Test-23 success Logs for test_progs_parallel on x86_64 with llvm-16
bpf/vmtest-bpf-next-VM_Test-21 success Logs for test_progs_parallel on aarch64 with gcc
bpf/vmtest-bpf-next-VM_Test-16 success Logs for test_progs_no_alu32 on x86_64 with gcc
bpf/vmtest-bpf-next-VM_Test-14 success Logs for test_progs_no_alu32 on aarch64 with gcc
bpf/vmtest-bpf-next-VM_Test-10 success Logs for test_progs on aarch64 with gcc
bpf/vmtest-bpf-next-VM_Test-25 success Logs for test_verifier on s390x with gcc
bpf/vmtest-bpf-next-VM_Test-15 success Logs for test_progs_no_alu32 on s390x with gcc
bpf/vmtest-bpf-next-VM_Test-11 success Logs for test_progs on s390x with gcc
bpf/vmtest-bpf-next-VM_Test-7 success Logs for test_maps on s390x with gcc

Commit Message

Yonghong Song Aug. 24, 2023, 6:34 a.m. UTC
Add a local kptr test with no special fields in the struct. Without the
previous patch, the following warning will hit:

  [   44.683877] WARNING: CPU: 3 PID: 485 at kernel/bpf/syscall.c:660 bpf_obj_free_fields+0x220/0x240
  [   44.684640] Modules linked in: bpf_testmod(OE)
  [   44.685044] CPU: 3 PID: 485 Comm: kworker/u8:5 Tainted: G           OE      6.5.0-rc5-01703-g260d855e9b90 #248
  [   44.685827] Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS rel-1.14.0-0-g155821a1990b-prebuilt.qemu.org 04/01/2014
  [   44.686693] Workqueue: events_unbound bpf_map_free_deferred
  [   44.687297] RIP: 0010:bpf_obj_free_fields+0x220/0x240
  [   44.687775] Code: e8 55 17 1f 00 49 8b 74 24 08 4c 89 ef e8 e8 14 05 00 e8 a3 da e2 ff e9 55 fe ff ff 0f 0b e9 4e fe ff
                       ff 0f 0b e9 47 fe ff ff <0f> 0b e8 d9 d9 e2 ff 31 f6 eb d5 48 83 c4 10 5b 41 5c e
  [   44.689353] RSP: 0018:ffff888106467cb8 EFLAGS: 00010246
  [   44.689806] RAX: 0000000000000000 RBX: ffff888112b3a200 RCX: 0000000000000001
  [   44.690433] RDX: 0000000000000000 RSI: dffffc0000000000 RDI: ffff8881128ad988
  [   44.691094] RBP: 0000000000000002 R08: ffffffff81370bd0 R09: 1ffff110216231a5
  [   44.691643] R10: dffffc0000000000 R11: ffffed10216231a6 R12: ffff88810d68a488
  [   44.692245] R13: ffff88810767c288 R14: ffff88810d68a400 R15: ffff88810d68a418
  [   44.692829] FS:  0000000000000000(0000) GS:ffff8881f7580000(0000) knlGS:0000000000000000
  [   44.693484] CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
  [   44.693964] CR2: 000055c7f2afce28 CR3: 000000010fee4002 CR4: 0000000000370ee0
  [   44.694513] DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
  [   44.695102] DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
  [   44.695747] Call Trace:
  [   44.696001]  <TASK>
  [   44.696183]  ? __warn+0xfe/0x270
  [   44.696447]  ? bpf_obj_free_fields+0x220/0x240
  [   44.696817]  ? report_bug+0x220/0x2d0
  [   44.697180]  ? handle_bug+0x3d/0x70
  [   44.697507]  ? exc_invalid_op+0x1a/0x50
  [   44.697887]  ? asm_exc_invalid_op+0x1a/0x20
  [   44.698282]  ? btf_find_struct_meta+0xd0/0xd0
  [   44.698634]  ? bpf_obj_free_fields+0x220/0x240
  [   44.699027]  ? bpf_obj_free_fields+0x1e2/0x240
  [   44.699414]  array_map_free+0x1a3/0x260
  [   44.699763]  bpf_map_free_deferred+0x7b/0xe0
  [   44.700154]  process_one_work+0x46d/0x750
  [   44.700523]  worker_thread+0x49e/0x900
  [   44.700892]  ? pr_cont_work+0x270/0x270
  [   44.701224]  kthread+0x1ae/0x1d0
  [   44.701516]  ? kthread_blkcg+0x50/0x50
  [   44.701860]  ret_from_fork+0x34/0x50
  [   44.702178]  ? kthread_blkcg+0x50/0x50
  [   44.702508]  ret_from_fork_asm+0x11/0x20
  [   44.702880]  </TASK>

With the previous patch, there is no warnings.

Signed-off-by: Yonghong Song <yonghong.song@linux.dev>
---
 .../bpf/prog_tests/local_kptr_stash.c         | 23 +++++++++++++++
 .../selftests/bpf/progs/local_kptr_stash.c    | 28 +++++++++++++++++++
 2 files changed, 51 insertions(+)
diff mbox series

Patch

diff --git a/tools/testing/selftests/bpf/prog_tests/local_kptr_stash.c b/tools/testing/selftests/bpf/prog_tests/local_kptr_stash.c
index 158616c94658..b25b870f87ba 100644
--- a/tools/testing/selftests/bpf/prog_tests/local_kptr_stash.c
+++ b/tools/testing/selftests/bpf/prog_tests/local_kptr_stash.c
@@ -27,6 +27,27 @@  static void test_local_kptr_stash_simple(void)
 	local_kptr_stash__destroy(skel);
 }
 
+static void test_local_kptr_stash_plain(void)
+{
+	LIBBPF_OPTS(bpf_test_run_opts, opts,
+		    .data_in = &pkt_v4,
+		    .data_size_in = sizeof(pkt_v4),
+		    .repeat = 1,
+	);
+	struct local_kptr_stash *skel;
+	int ret;
+
+	skel = local_kptr_stash__open_and_load();
+	if (!ASSERT_OK_PTR(skel, "local_kptr_stash__open_and_load"))
+		return;
+
+	ret = bpf_prog_test_run_opts(bpf_program__fd(skel->progs.stash_plain), &opts);
+	ASSERT_OK(ret, "local_kptr_stash_add_plain run");
+	ASSERT_OK(opts.retval, "local_kptr_stash_add_plain retval");
+
+	local_kptr_stash__destroy(skel);
+}
+
 static void test_local_kptr_stash_unstash(void)
 {
 	LIBBPF_OPTS(bpf_test_run_opts, opts,
@@ -61,6 +82,8 @@  void test_local_kptr_stash(void)
 {
 	if (test__start_subtest("local_kptr_stash_simple"))
 		test_local_kptr_stash_simple();
+	if (test__start_subtest("local_kptr_stash_plain"))
+		test_local_kptr_stash_plain();
 	if (test__start_subtest("local_kptr_stash_unstash"))
 		test_local_kptr_stash_unstash();
 	if (test__start_subtest("local_kptr_stash_fail"))
diff --git a/tools/testing/selftests/bpf/progs/local_kptr_stash.c b/tools/testing/selftests/bpf/progs/local_kptr_stash.c
index 06838083079c..b567a666d2b8 100644
--- a/tools/testing/selftests/bpf/progs/local_kptr_stash.c
+++ b/tools/testing/selftests/bpf/progs/local_kptr_stash.c
@@ -14,10 +14,16 @@  struct node_data {
 	struct bpf_rb_node node;
 };
 
+struct plain_local {
+	long key;
+	long data;
+};
+
 struct map_value {
 	struct prog_test_ref_kfunc *not_kptr;
 	struct prog_test_ref_kfunc __kptr *val;
 	struct node_data __kptr *node;
+	struct plain_local __kptr *plain;
 };
 
 /* This is necessary so that LLVM generates BTF for node_data struct
@@ -66,6 +72,28 @@  long stash_rb_nodes(void *ctx)
 	return create_and_stash(0, 41) ?: create_and_stash(1, 42);
 }
 
+SEC("tc")
+long stash_plain(void *ctx)
+{
+	struct map_value *mapval;
+	struct plain_local *res;
+	int idx = 0;
+
+	mapval = bpf_map_lookup_elem(&some_nodes, &idx);
+	if (!mapval)
+		return 1;
+
+	res = bpf_obj_new(typeof(*res));
+	if (!res)
+		return 1;
+	res->key = 41;
+
+	res = bpf_kptr_xchg(&mapval->plain, res);
+	if (res)
+		bpf_obj_drop(res);
+	return 0;
+}
+
 SEC("tc")
 long unstash_rb_node(void *ctx)
 {