[PATCH 7.1.y v3] selftests/bpf: Add tests for sleepable tracepoint programs

From: Mykyta Yatsenko <[email protected]>

[ Upstream commit 8a20655749c625dcc4debdfdeeaa0cf8bb85c203 ]

Cover all three sleepable tracepoint types (tp_btf.s, raw_tp.s, tp.s)
and sys_exit (via bpf_task_pt_regs) with functional tests using
bpf_copy_from_user() on getcwd. Verify alias and bare SEC variants,
bpf_prog_test_run_raw_tp() with BPF_F_TEST_RUN_ON_CPU rejection,
attach-time rejection on non-faultable tracepoints, and load-time
rejection for sleepable tp_btf on non-faultable tracepoints.

[ rbm: Removed hunks from (new) files:
        tools/testing/selftests/bpf/prog_tests/sleepable_tracepoints.c
        tools/testing/selftests/bpf/progs/test_sleepable_tracepoints.c
        tools/testing/selftests/bpf/progs/test_sleepable_tracepoints_fail.c
       These rely on libbpf's ".s" tracepoint section handlers
       (0cd420a6f40c7) and on kernel-side sleepable tracepoint runtime
       support (439ebd5b5708, 12628ffaf98b, 57918341dd19), none of which
       are backported here; kept only the verifier/sleepable.c hunk, which
       is correct and needed on its own. ]

Signed-off-by: Mykyta Yatsenko <[email protected]>
Acked-by: Kumar Kartikeya Dwivedi <[email protected]>
Link: https://lore.kernel.org/bpf/[email protected]
Signed-off-by: Kumar Kartikeya Dwivedi <[email protected]>
Signed-off-by: Ricardo B. Marlière (SUSE) <[email protected]>
---
Hi, backporting commit 23b933c6223f ("bpf: Verifier support for sleepable
tracepoint programs") without backporting this commit breaks the selftest,
as seen in openSUSE CI:

https://openqa.opensuse.org/tests/6145723/logfile?filename=test_verifier.tap.txt#line-780

Changes in v3:
- Sign off
- Link to v2: https://patch.msgid.link/[email protected]

Changes in v2:
- Dropped hunks which miss dependencies
- Added a small note about it in the commit
- Link to v1: https://patch.msgid.link/[email protected]
---
 tools/testing/selftests/bpf/verifier/sleepable.c | 17 +++++++++++++++--
 1 file changed, 15 insertions(+), 2 deletions(-)

diff --git a/tools/testing/selftests/bpf/verifier/sleepable.c b/tools/testing/selftests/bpf/verifier/sleepable.c
index c2b7f5ebf168..6dabc5522945 100644
--- a/tools/testing/selftests/bpf/verifier/sleepable.c
+++ b/tools/testing/selftests/bpf/verifier/sleepable.c
@@ -76,7 +76,20 @@
 	.runs = -1,
 },
 {
-	"sleepable raw tracepoint reject",
+	"sleepable raw tracepoint accept",
+	.insns = {
+	BPF_MOV64_IMM(BPF_REG_0, 0),
+	BPF_EXIT_INSN(),
+	},
+	.prog_type = BPF_PROG_TYPE_TRACING,
+	.expected_attach_type = BPF_TRACE_RAW_TP,
+	.kfunc = "sys_enter",
+	.result = ACCEPT,
+	.flags = BPF_F_SLEEPABLE,
+	.runs = -1,
+},
+{
+	"sleepable raw tracepoint reject non-faultable",
 	.insns = {
 	BPF_MOV64_IMM(BPF_REG_0, 0),
 	BPF_EXIT_INSN(),
@@ -85,7 +98,7 @@
 	.expected_attach_type = BPF_TRACE_RAW_TP,
 	.kfunc = "sched_switch",
 	.result = REJECT,
-	.errstr = "Only fentry/fexit/fsession/fmod_ret, lsm, iter, uprobe, and struct_ops programs can be sleepable",
+	.errstr = "Sleepable program cannot attach to non-faultable tracepoint",
 	.flags = BPF_F_SLEEPABLE,
 	.runs = -1,
 },

---
base-commit: 74b69060ba6e44e20c2e4dc1847eca21db6e4a7c
change-id: 20260803-selftests-bpf-sleepable-eebf2d962201

Best regards,
--  
Ricardo B. Marlière (SUSE) <[email protected]>