Kumar is working on adding exceptions to BPF and enabling it on x86 [1].
I am working with him to enable it on ARM64 and will later do it for
other architectures when the basic exceptions support is upstream.

This patch enables the support on ARM64, all sefltests are passing:

# ./test_progs -a exceptions
#74/1    exceptions/exception_throw_always_1:OK
#74/2    exceptions/exception_throw_always_2:OK
#74/3    exceptions/exception_throw_unwind_1:OK
#74/4    exceptions/exception_throw_unwind_2:OK
#74/5    exceptions/exception_throw_default:OK
#74/6    exceptions/exception_throw_default_value:OK
#74/7    exceptions/exception_tail_call:OK
#74/8    exceptions/exception_ext:OK
#74/9    exceptions/exception_ext_mod_cb_runtime:OK
#74/10   exceptions/exception_throw_subprog:OK
#74/11   exceptions/exception_assert_nz_gfunc:OK
#74/12   exceptions/exception_assert_zero_gfunc:OK
#74/13   exceptions/exception_assert_neg_gfunc:OK
#74/14   exceptions/exception_assert_pos_gfunc:OK
#74/15   exceptions/exception_assert_negeq_gfunc:OK
#74/16   exceptions/exception_assert_poseq_gfunc:OK
#74/17   exceptions/exception_assert_nz_gfunc_with:OK
#74/18   exceptions/exception_assert_zero_gfunc_with:OK
#74/19   exceptions/exception_assert_neg_gfunc_with:OK
#74/20   exceptions/exception_assert_pos_gfunc_with:OK
#74/21   exceptions/exception_assert_negeq_gfunc_with:OK
#74/22   exceptions/exception_assert_poseq_gfunc_with:OK
#74/23   exceptions/exception_bad_assert_nz_gfunc:OK
#74/24   exceptions/exception_bad_assert_zero_gfunc:OK
#74/25   exceptions/exception_bad_assert_neg_gfunc:OK
#74/26   exceptions/exception_bad_assert_pos_gfunc:OK
#74/27   exceptions/exception_bad_assert_negeq_gfunc:OK
#74/28   exceptions/exception_bad_assert_poseq_gfunc:OK
#74/29   exceptions/exception_bad_assert_nz_gfunc_with:OK
#74/30   exceptions/exception_bad_assert_zero_gfunc_with:OK
#74/31   exceptions/exception_bad_assert_neg_gfunc_with:OK
#74/32   exceptions/exception_bad_assert_pos_gfunc_with:OK
#74/33   exceptions/exception_bad_assert_negeq_gfunc_with:OK
#74/34   exceptions/exception_bad_assert_poseq_gfunc_with:OK
#74/35   exceptions/exception_assert_range:OK
#74/36   exceptions/exception_assert_range_with:OK
#74/37   exceptions/exception_bad_assert_range:OK
#74/38   exceptions/exception_bad_assert_range_with:OK
#74/39   exceptions/non-throwing fentry -> exception_cb:OK
#74/40   exceptions/throwing fentry -> exception_cb:OK
#74/41   exceptions/non-throwing fexit -> exception_cb:OK
#74/42   exceptions/throwing fexit -> exception_cb:OK
#74/43   exceptions/throwing extension (with custom cb) -> exception_cb:OK
#74/44   exceptions/throwing extension -> global func in exception_cb:OK
#74/45   exceptions/exception_ext_mod_cb_runtime:OK
#74/46   exceptions/throwing extension (with custom cb) -> global func in exception_cb:OK
#74/47   exceptions/exception_ext:OK
#74/48   exceptions/non-throwing fentry -> non-throwing subprog:OK
#74/49   exceptions/throwing fentry -> non-throwing subprog:OK
#74/50   exceptions/non-throwing fentry -> throwing subprog:OK
#74/51   exceptions/throwing fentry -> throwing subprog:OK
#74/52   exceptions/non-throwing fexit -> non-throwing subprog:OK
#74/53   exceptions/throwing fexit -> non-throwing subprog:OK
#74/54   exceptions/non-throwing fexit -> throwing subprog:OK
#74/55   exceptions/throwing fexit -> throwing subprog:OK
#74/56   exceptions/non-throwing fmod_ret -> non-throwing subprog:OK
#74/57   exceptions/non-throwing fmod_ret -> non-throwing global subprog:OK
#74/58   exceptions/non-throwing extension -> non-throwing subprog:OK
#74/59   exceptions/non-throwing extension -> throwing subprog:OK
#74/60   exceptions/non-throwing extension -> non-throwing subprog:OK
#74/61   exceptions/non-throwing extension -> throwing global subprog:OK
#74/62   exceptions/throwing extension -> throwing global subprog:OK
#74/63   exceptions/throwing extension -> non-throwing global subprog:OK
#74/64   exceptions/non-throwing extension -> main subprog:OK
#74/65   exceptions/throwing extension -> main subprog:OK
#74/66   exceptions/reject_exception_cb_type_1:OK
#74/67   exceptions/reject_exception_cb_type_2:OK
#74/68   exceptions/reject_exception_cb_type_3:OK
#74/69   exceptions/reject_exception_cb_type_4:OK
#74/70   exceptions/reject_async_callback_throw:OK
#74/71   exceptions/reject_with_lock:OK
#74/72   exceptions/reject_subprog_with_lock:OK
#74/73   exceptions/reject_with_rcu_read_lock:OK
#74/74   exceptions/reject_subprog_with_rcu_read_lock:OK
#74/75   exceptions/reject_with_rbtree_add_throw:OK
#74/76   exceptions/reject_with_reference:OK
#74/77   exceptions/reject_with_cb_reference:OK
#74/78   exceptions/reject_with_cb:OK
#74/79   exceptions/reject_with_subprog_reference:OK
#74/80   exceptions/reject_throwing_exception_cb:OK
#74/81   exceptions/reject_exception_cb_call_global_func:OK
#74/82   exceptions/reject_exception_cb_call_static_func:OK
#74/83   exceptions/reject_multiple_exception_cb:OK
#74/84   exceptions/reject_exception_throw_cb:OK
#74/85   exceptions/reject_exception_throw_cb_diff:OK
#74/86   exceptions/reject_set_exception_cb_bad_ret1:OK
#74/87   exceptions/reject_set_exception_cb_bad_ret2:OK
#74/88   exceptions/check_assert_eq_int_min:OK
#74/89   exceptions/check_assert_eq_int_max:OK
#74/90   exceptions/check_assert_eq_zero:OK
#74/91   exceptions/check_assert_eq_llong_min:OK
#74/92   exceptions/check_assert_eq_llong_max:OK
#74/93   exceptions/check_assert_lt_pos:OK
#74/94   exceptions/check_assert_lt_zero:OK
#74/95   exceptions/check_assert_lt_neg:OK
#74/96   exceptions/check_assert_le_pos:OK
#74/97   exceptions/check_assert_le_zero:OK
#74/98   exceptions/check_assert_le_neg:OK
#74/99   exceptions/check_assert_gt_pos:OK
#74/100  exceptions/check_assert_gt_zero:OK
#74/101  exceptions/check_assert_gt_neg:OK
#74/102  exceptions/check_assert_ge_pos:OK
#74/103  exceptions/check_assert_ge_zero:OK
#74/104  exceptions/check_assert_ge_neg:OK
#74/105  exceptions/check_assert_range_s64:OK
#74/106  exceptions/check_assert_range_u64:OK
#74/107  exceptions/check_assert_single_range_s64:OK
#74/108  exceptions/check_assert_single_range_u64:OK
#74/109  exceptions/check_assert_generic:OK
#74/110  exceptions/check_assert_with_return:OK
#74      exceptions:OK
Summary: 1/110 PASSED, 0 SKIPPED, 0 FAILED

[1] https://lore.kernel.org/bpf/20230912233214.1518551-1-memxor@gmail.com/

Puranjay Mohan (1):
  bpf, arm64: support exceptions

 arch/arm64/net/bpf_jit_comp.c | 98 ++++++++++++++++++++++++++++-------
 1 file changed, 79 insertions(+), 19 deletions(-)

-- 
2.40.1

On Wed, 13 Sept 2023 at 23:46, Puranjay Mohan <puranjay12@gmail.com> wrote:
>
> Kumar is working on adding exceptions to BPF and enabling it on x86 [1].
> I am working with him to enable it on ARM64 and will later do it for
> other architectures when the basic exceptions support is upstream.
>

Sorry for the noise.
Please ignore this [resent] email.

Thanks,
Puranjay