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author | Yonghong Song <yonghong.song@linux.dev> | 2024-09-04 15:12:56 -0700 |
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committer | Alexei Starovoitov <ast@kernel.org> | 2024-09-04 16:46:22 -0700 |
commit | eff5b5fffc1d39fb9e5e66d6aa4ed3fcb109caac (patch) | |
tree | 2e3852a76c55a56d84a47afc852212776c697a57 /tools/testing/selftests/bpf | |
parent | c8831bdbfbab672c006a18006d36932a494b2fd6 (diff) | |
download | linux-eff5b5fffc1d39fb9e5e66d6aa4ed3fcb109caac.tar.gz linux-eff5b5fffc1d39fb9e5e66d6aa4ed3fcb109caac.tar.bz2 linux-eff5b5fffc1d39fb9e5e66d6aa4ed3fcb109caac.zip |
selftests/bpf: Add a selftest for x86 jit convergence issues
The core part of the selftest, i.e., the je <-> jmp cycle, mimics the
original sched-ext bpf program. The test will fail without the
previous patch.
I tried to create some cases for other potential cycles
(je <-> je, jmp <-> je and jmp <-> jmp) with similar pattern
to the test in this patch, but failed. So this patch
only contains one test for je <-> jmp cycle.
Signed-off-by: Yonghong Song <yonghong.song@linux.dev>
Link: https://lore.kernel.org/r/20240904221256.37389-1-yonghong.song@linux.dev
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Diffstat (limited to 'tools/testing/selftests/bpf')
-rw-r--r-- | tools/testing/selftests/bpf/prog_tests/verifier.c | 2 | ||||
-rw-r--r-- | tools/testing/selftests/bpf/progs/verifier_jit_convergence.c | 114 |
2 files changed, 116 insertions, 0 deletions
diff --git a/tools/testing/selftests/bpf/prog_tests/verifier.c b/tools/testing/selftests/bpf/prog_tests/verifier.c index 80a90c627182..df398e714dff 100644 --- a/tools/testing/selftests/bpf/prog_tests/verifier.c +++ b/tools/testing/selftests/bpf/prog_tests/verifier.c @@ -39,6 +39,7 @@ #include "verifier_int_ptr.skel.h" #include "verifier_iterating_callbacks.skel.h" #include "verifier_jeq_infer_not_null.skel.h" +#include "verifier_jit_convergence.skel.h" #include "verifier_ld_ind.skel.h" #include "verifier_ldsx.skel.h" #include "verifier_leak_ptr.skel.h" @@ -163,6 +164,7 @@ void test_verifier_helper_value_access(void) { RUN(verifier_helper_value_access void test_verifier_int_ptr(void) { RUN(verifier_int_ptr); } void test_verifier_iterating_callbacks(void) { RUN(verifier_iterating_callbacks); } void test_verifier_jeq_infer_not_null(void) { RUN(verifier_jeq_infer_not_null); } +void test_verifier_jit_convergence(void) { RUN(verifier_jit_convergence); } void test_verifier_ld_ind(void) { RUN(verifier_ld_ind); } void test_verifier_ldsx(void) { RUN(verifier_ldsx); } void test_verifier_leak_ptr(void) { RUN(verifier_leak_ptr); } diff --git a/tools/testing/selftests/bpf/progs/verifier_jit_convergence.c b/tools/testing/selftests/bpf/progs/verifier_jit_convergence.c new file mode 100644 index 000000000000..9f3f2b7db450 --- /dev/null +++ b/tools/testing/selftests/bpf/progs/verifier_jit_convergence.c @@ -0,0 +1,114 @@ +// SPDX-License-Identifier: GPL-2.0 +/* Copyright (c) 2024 Meta Platforms, Inc. and affiliates. */ + +#include <linux/bpf.h> +#include <bpf/bpf_helpers.h> +#include "bpf_misc.h" + +struct value_t { + long long a[32]; +}; + +struct { + __uint(type, BPF_MAP_TYPE_HASH); + __uint(max_entries, 1); + __type(key, long long); + __type(value, struct value_t); +} map_hash SEC(".maps"); + +SEC("socket") +__description("bpf_jit_convergence je <-> jmp") +__success __retval(0) +__arch_x86_64 +__jited(" pushq %rbp") +__naked void btf_jit_convergence_je_jmp(void) +{ + asm volatile ( + "call %[bpf_get_prandom_u32];" + "if r0 == 0 goto l20_%=;" + "if r0 == 1 goto l21_%=;" + "if r0 == 2 goto l22_%=;" + "if r0 == 3 goto l23_%=;" + "if r0 == 4 goto l24_%=;" + "call %[bpf_get_prandom_u32];" + "call %[bpf_get_prandom_u32];" +"l20_%=:" +"l21_%=:" +"l22_%=:" +"l23_%=:" +"l24_%=:" + "r1 = 0;" + "*(u64 *)(r10 - 8) = r1;" + "r2 = r10;" + "r2 += -8;" + "r1 = %[map_hash] ll;" + "call %[bpf_map_lookup_elem];" + "if r0 == 0 goto l1_%=;" + "r6 = r0;" + "call %[bpf_get_prandom_u32];" + "r7 = r0;" + "r5 = r6;" + "if r0 != 0x0 goto l12_%=;" + "call %[bpf_get_prandom_u32];" + "r1 = r0;" + "r2 = r6;" + "if r1 == 0x0 goto l0_%=;" +"l9_%=:" + "r2 = *(u64 *)(r6 + 0x0);" + "r2 += 0x1;" + "*(u64 *)(r6 + 0x0) = r2;" + "goto l1_%=;" +"l12_%=:" + "r1 = r7;" + "r1 += 0x98;" + "r2 = r5;" + "r2 += 0x90;" + "r2 = *(u32 *)(r2 + 0x0);" + "r3 = r7;" + "r3 &= 0x1;" + "r2 *= 0xa8;" + "if r3 == 0x0 goto l2_%=;" + "r1 += r2;" + "r1 -= r7;" + "r1 += 0x8;" + "if r1 <= 0xb20 goto l3_%=;" + "r1 = 0x0;" + "goto l4_%=;" +"l3_%=:" + "r1 += r7;" +"l4_%=:" + "if r1 == 0x0 goto l8_%=;" + "goto l9_%=;" +"l2_%=:" + "r1 += r2;" + "r1 -= r7;" + "r1 += 0x10;" + "if r1 <= 0xb20 goto l6_%=;" + "r1 = 0x0;" + "goto l7_%=;" +"l6_%=:" + "r1 += r7;" +"l7_%=:" + "if r1 == 0x0 goto l8_%=;" + "goto l9_%=;" +"l0_%=:" + "r1 = 0x3;" + "*(u64 *)(r10 - 0x10) = r1;" + "r2 = r1;" + "goto l1_%=;" +"l8_%=:" + "r1 = r5;" + "r1 += 0x4;" + "r1 = *(u32 *)(r1 + 0x0);" + "*(u64 *)(r10 - 0x8) = r1;" +"l1_%=:" + "r0 = 0;" + "exit;" + : + : __imm(bpf_get_prandom_u32), + __imm(bpf_map_lookup_elem), + __imm_addr(map_hash) + : __clobber_all); +} + +char _license[] SEC("license") = "GPL"; |