1 files changed, 94 insertions, 15 deletions

diff --git a/tools/bpf/bpftool/feature.c b/tools/bpf/bpftool/feature.c
index 6719b9282eca..e999159fa28d 100644
--- a/tools/bpf/bpftool/feature.c
+++ b/tools/bpf/bpftool/feature.c
@@ -642,6 +642,30 @@ probe_helpers_for_progtype(enum bpf_prog_type prog_type, bool supported_type,
 		printf("\n");
 }
 
+static void
+probe_misc_feature(struct bpf_insn *insns, size_t len,
+		   const char *define_prefix, __u32 ifindex,
+		   const char *feat_name, const char *plain_name,
+		   const char *define_name)
+{
+	LIBBPF_OPTS(bpf_prog_load_opts, opts,
+		.prog_ifindex = ifindex,
+	);
+	bool res;
+	int fd;
+
+	errno = 0;
+	fd = bpf_prog_load(BPF_PROG_TYPE_SOCKET_FILTER, NULL, "GPL",
+			   insns, len, &opts);
+	res = fd >= 0 || !errno;
+
+	if (fd >= 0)
+		close(fd);
+
+	print_bool_feature(feat_name, plain_name, define_name, res,
+			   define_prefix);
+}
+
 /*
  * Probe for availability of kernel commit (5.3):
  *
@@ -649,29 +673,81 @@ probe_helpers_for_progtype(enum bpf_prog_type prog_type, bool supported_type,
  */
 static void probe_large_insn_limit(const char *define_prefix, __u32 ifindex)
 {
-	LIBBPF_OPTS(bpf_prog_load_opts, opts,
-		.prog_ifindex = ifindex,
-	);
 	struct bpf_insn insns[BPF_MAXINSNS + 1];
-	bool res;
-	int i, fd;
+	int i;
 
 	for (i = 0; i < BPF_MAXINSNS; i++)
 		insns[i] = BPF_MOV64_IMM(BPF_REG_0, 1);
 	insns[BPF_MAXINSNS] = BPF_EXIT_INSN();
 
-	errno = 0;
-	fd = bpf_prog_load(BPF_PROG_TYPE_SCHED_CLS, NULL, "GPL",
-			   insns, ARRAY_SIZE(insns), &opts);
-	res = fd >= 0 || (errno != E2BIG && errno != EINVAL);
+	probe_misc_feature(insns, ARRAY_SIZE(insns),
+			   define_prefix, ifindex,
+			   "have_large_insn_limit",
+			   "Large program size limit",
+			   "LARGE_INSN_LIMIT");
+}
 
-	if (fd >= 0)
-		close(fd);
+/*
+ * Probe for bounded loop support introduced in commit 2589726d12a1
+ * ("bpf: introduce bounded loops").
+ */
+static void
+probe_bounded_loops(const char *define_prefix, __u32 ifindex)
+{
+	struct bpf_insn insns[4] = {
+		BPF_MOV64_IMM(BPF_REG_0, 10),
+		BPF_ALU64_IMM(BPF_SUB, BPF_REG_0, 1),
+		BPF_JMP_IMM(BPF_JNE, BPF_REG_0, 0, -2),
+		BPF_EXIT_INSN()
+	};
 
-	print_bool_feature("have_large_insn_limit",
-			   "Large program size limit",
-			   "LARGE_INSN_LIMIT",
-			   res, define_prefix);
+	probe_misc_feature(insns, ARRAY_SIZE(insns),
+			   define_prefix, ifindex,
+			   "have_bounded_loops",
+			   "Bounded loop support",
+			   "BOUNDED_LOOPS");
+}
+
+/*
+ * Probe for the v2 instruction set extension introduced in commit 92b31a9af73b
+ * ("bpf: add BPF_J{LT,LE,SLT,SLE} instructions").
+ */
+static void
+probe_v2_isa_extension(const char *define_prefix, __u32 ifindex)
+{
+	struct bpf_insn insns[4] = {
+		BPF_MOV64_IMM(BPF_REG_0, 0),
+		BPF_JMP_IMM(BPF_JLT, BPF_REG_0, 0, 1),
+		BPF_MOV64_IMM(BPF_REG_0, 1),
+		BPF_EXIT_INSN()
+	};
+
+	probe_misc_feature(insns, ARRAY_SIZE(insns),
+			   define_prefix, ifindex,
+			   "have_v2_isa_extension",
+			   "ISA extension v2",
+			   "V2_ISA_EXTENSION");
+}
+
+/*
+ * Probe for the v3 instruction set extension introduced in commit 092ed0968bb6
+ * ("bpf: verifier support JMP32").
+ */
+static void
+probe_v3_isa_extension(const char *define_prefix, __u32 ifindex)
+{
+	struct bpf_insn insns[4] = {
+		BPF_MOV64_IMM(BPF_REG_0, 0),
+		BPF_JMP32_IMM(BPF_JLT, BPF_REG_0, 0, 1),
+		BPF_MOV64_IMM(BPF_REG_0, 1),
+		BPF_EXIT_INSN()
+	};
+
+	probe_misc_feature(insns, ARRAY_SIZE(insns),
+			   define_prefix, ifindex,
+			   "have_v3_isa_extension",
+			   "ISA extension v3",
+			   "V3_ISA_EXTENSION");
 }
 
 static void
@@ -788,6 +864,9 @@ static void section_misc(const char *define_prefix, __u32 ifindex)
 			    "/*** eBPF misc features ***/",
 			    define_prefix);
 	probe_large_insn_limit(define_prefix, ifindex);
+	probe_bounded_loops(define_prefix, ifindex);
+	probe_v2_isa_extension(define_prefix, ifindex);
+	probe_v3_isa_extension(define_prefix, ifindex);
 	print_end_section();
 }