This reverts commit 4af2d9ddb7e78f97c23f709827e5075c6d866e34.
The backport of bpf precision tracking related changes has caused bpf verifier to panic while loading some certain bpf prog so revert them.
Link: https://lkml.kernel.org/r/20250605070921.GA3795@bytedance/ Reported-by: Wei Wei weiwei.danny@bytedance.com Signed-off-by: Aaron Lu ziqianlu@bytedance.com --- .../testing/selftests/bpf/prog_tests/align.c | 36 +++++++------------ 1 file changed, 13 insertions(+), 23 deletions(-)
diff --git a/tools/testing/selftests/bpf/prog_tests/align.c b/tools/testing/selftests/bpf/prog_tests/align.c index 7996ec07e0bdb..5861446d07770 100644 --- a/tools/testing/selftests/bpf/prog_tests/align.c +++ b/tools/testing/selftests/bpf/prog_tests/align.c @@ -2,7 +2,7 @@ #include <test_progs.h>
#define MAX_INSNS 512 -#define MAX_MATCHES 24 +#define MAX_MATCHES 16
struct bpf_reg_match { unsigned int line; @@ -267,7 +267,6 @@ static struct bpf_align_test tests[] = { */ BPF_MOV64_REG(BPF_REG_5, BPF_REG_2), BPF_ALU64_REG(BPF_ADD, BPF_REG_5, BPF_REG_6), - BPF_MOV64_REG(BPF_REG_4, BPF_REG_5), BPF_ALU64_IMM(BPF_ADD, BPF_REG_5, 14), BPF_MOV64_REG(BPF_REG_4, BPF_REG_5), BPF_ALU64_IMM(BPF_ADD, BPF_REG_4, 4), @@ -281,7 +280,6 @@ static struct bpf_align_test tests[] = { BPF_MOV64_REG(BPF_REG_5, BPF_REG_2), BPF_ALU64_IMM(BPF_ADD, BPF_REG_5, 14), BPF_ALU64_REG(BPF_ADD, BPF_REG_5, BPF_REG_6), - BPF_MOV64_REG(BPF_REG_4, BPF_REG_5), BPF_ALU64_IMM(BPF_ADD, BPF_REG_5, 4), BPF_ALU64_REG(BPF_ADD, BPF_REG_5, BPF_REG_6), BPF_MOV64_REG(BPF_REG_4, BPF_REG_5), @@ -313,52 +311,44 @@ static struct bpf_align_test tests[] = { {15, "R4=pkt(id=1,off=18,r=18,umax_value=1020,var_off=(0x0; 0x3fc))"}, {15, "R5=pkt(id=1,off=14,r=18,umax_value=1020,var_off=(0x0; 0x3fc))"}, /* Variable offset is added to R5 packet pointer, - * resulting in auxiliary alignment of 4. To avoid BPF - * verifier's precision backtracking logging - * interfering we also have a no-op R4 = R5 - * instruction to validate R5 state. We also check - * that R4 is what it should be in such case. + * resulting in auxiliary alignment of 4. */ - {19, "R4_w=pkt(id=2,off=0,r=0,umax_value=1020,var_off=(0x0; 0x3fc))"}, - {19, "R5_w=pkt(id=2,off=0,r=0,umax_value=1020,var_off=(0x0; 0x3fc))"}, + {18, "R5_w=pkt(id=2,off=0,r=0,umax_value=1020,var_off=(0x0; 0x3fc))"}, /* Constant offset is added to R5, resulting in * reg->off of 14. */ - {20, "R5_w=pkt(id=2,off=14,r=0,umax_value=1020,var_off=(0x0; 0x3fc))"}, + {19, "R5_w=pkt(id=2,off=14,r=0,umax_value=1020,var_off=(0x0; 0x3fc))"}, /* At the time the word size load is performed from R5, * its total fixed offset is NET_IP_ALIGN + reg->off * (14) which is 16. Then the variable offset is 4-byte * aligned, so the total offset is 4-byte aligned and * meets the load's requirements. */ - {24, "R4=pkt(id=2,off=18,r=18,umax_value=1020,var_off=(0x0; 0x3fc))"}, - {24, "R5=pkt(id=2,off=14,r=18,umax_value=1020,var_off=(0x0; 0x3fc))"}, + {23, "R4=pkt(id=2,off=18,r=18,umax_value=1020,var_off=(0x0; 0x3fc))"}, + {23, "R5=pkt(id=2,off=14,r=18,umax_value=1020,var_off=(0x0; 0x3fc))"}, /* Constant offset is added to R5 packet pointer, * resulting in reg->off value of 14. */ - {27, "R5_w=pkt(id=0,off=14,r=8"}, + {26, "R5_w=pkt(id=0,off=14,r=8"}, /* Variable offset is added to R5, resulting in a - * variable offset of (4n). See comment for insn #19 - * for R4 = R5 trick. + * variable offset of (4n). */ - {29, "R4_w=pkt(id=3,off=14,r=0,umax_value=1020,var_off=(0x0; 0x3fc))"}, - {29, "R5_w=pkt(id=3,off=14,r=0,umax_value=1020,var_off=(0x0; 0x3fc))"}, + {27, "R5_w=pkt(id=3,off=14,r=0,umax_value=1020,var_off=(0x0; 0x3fc))"}, /* Constant is added to R5 again, setting reg->off to 18. */ - {30, "R5_w=pkt(id=3,off=18,r=0,umax_value=1020,var_off=(0x0; 0x3fc))"}, + {28, "R5_w=pkt(id=3,off=18,r=0,umax_value=1020,var_off=(0x0; 0x3fc))"}, /* And once more we add a variable; resulting var_off * is still (4n), fixed offset is not changed. * Also, we create a new reg->id. */ - {32, "R4_w=pkt(id=4,off=18,r=0,umax_value=2040,var_off=(0x0; 0x7fc)"}, - {32, "R5_w=pkt(id=4,off=18,r=0,umax_value=2040,var_off=(0x0; 0x7fc)"}, + {29, "R5_w=pkt(id=4,off=18,r=0,umax_value=2040,var_off=(0x0; 0x7fc)"}, /* At the time the word size load is performed from R5, * its total fixed offset is NET_IP_ALIGN + reg->off (18) * which is 20. Then the variable offset is (4n), so * the total offset is 4-byte aligned and meets the * load's requirements. */ - {35, "R4=pkt(id=4,off=22,r=22,umax_value=2040,var_off=(0x0; 0x7fc)"}, - {35, "R5=pkt(id=4,off=18,r=22,umax_value=2040,var_off=(0x0; 0x7fc)"}, + {33, "R4=pkt(id=4,off=22,r=22,umax_value=2040,var_off=(0x0; 0x7fc)"}, + {33, "R5=pkt(id=4,off=18,r=22,umax_value=2040,var_off=(0x0; 0x7fc)"}, }, }, {