bpf: Use NOP_ATOMIC5 instead of emit_nops(&prog, 5) for BPF_TRAMP_F_CALL_ORIG
[ Upstream commit b9082970 ] __bpf_arch_text_poke does rewrite only for atomic nop5, emit_nops(xxx, 5) emits non-atomic one which breaks fentry/fexit with k8 atomics: P6_NOP5 == P6_NOP5_ATOMIC (0f1f440000 == 0f1f440000) K8_NOP5 != K8_NOP5_ATOMIC (6666906690 != 6666666690) Can be reproduced by doing "ideal_nops = k8_nops" in "arch_init_ideal_nops() and running fexit_bpf2bpf selftest. Fixes: e21aa341 ("bpf: Fix fexit trampoline.") Signed-off-by:Stanislav Fomichev <sdf@google.com> Signed-off-by:
Alexei Starovoitov <ast@kernel.org> Link: https://lore.kernel.org/bpf/20210320000001.915366-1-sdf@google.com Signed-off-by:
Sasha Levin <sashal@kernel.org>
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