Daniel Borkmann 21a71e1146 bpf: Introduce BPF nospec instruction for mitigating Spectre v4 ... commit f5e81d1117501546b7be050c5fbafa6efd2c722c upstream. In case of JITs, each of the JIT backends compiles the BPF nospec instruction /either/ to a machine instruction which emits a speculation barrier /or/ to /no/ machine instruction in case the underlying architecture is not affected by Speculative Store Bypass or has different mitigations in place already. This covers both x86 and (implicitly) arm64: In case of x86, we use 'lfence' instruction for mitigation. In case of arm64, we rely on the firmware mitigation as controlled via the ssbd kernel parameter. Whenever the mitigation is enabled, it works for all of the kernel code with no need to provide any additional instructions here (hence only comment in arm64 JIT). Other archs can follow as needed. The BPF nospec instruction is specifically targeting Spectre v4 since i) we don't use a serialization barrier for the Spectre v1 case, and ii) mitigation instructions for v1 and v4 might be different on some archs. The BPF nospec is required for a future commit, where the BPF verifier does annotate intermediate BPF programs with speculation barriers. Co-developed-by: Piotr Krysiuk <piotras@gmail.com> Co-developed-by: Benedict Schlueter <benedict.schlueter@rub.de> Signed-off-by: Daniel Borkmann <daniel@iogearbox.net> Signed-off-by: Piotr Krysiuk <piotras@gmail.com> Signed-off-by: Benedict Schlueter <benedict.schlueter@rub.de> Acked-by: Alexei Starovoitov <ast@kernel.org> Signed-off-by: Sasha Levin <sashal@kernel.org> [OP: - adjusted context for 5.4 - apply riscv changes to /arch/riscv/net/bpf_jit_comp.c] Signed-off-by: Ovidiu Panait <ovidiu.panait@windriver.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>		2022-06-21 10:27:02 +08:00
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appldata	Init Repo base on linux 5.4.32 long term, and add base tlinux kernel interfaces.	2021-03-16 11:01:34 +08:00
boot	s390/startup: avoid save_area_sync overflow	2021-03-16 16:39:41 +08:00
configs	Init Repo base on linux 5.4.32 long term, and add base tlinux kernel interfaces.	2021-03-16 11:01:34 +08:00
crypto	s390/archrandom: add parameter check for s390_arch_random_generate	2021-05-20 16:07:32 +08:00
hypfs	Init Repo base on linux 5.4.32 long term, and add base tlinux kernel interfaces.	2021-03-16 11:01:34 +08:00
include	mm/gup: fix gup_fast with dynamic page table folding	2021-03-16 16:37:40 +08:00
kernel	s390: fix detection of vector enhancements facility 1 vs. vector packed decimal facility	2021-05-20 16:07:43 +08:00
kvm	KVM: s390: split kvm_s390_real_to_abs	2021-05-20 16:07:43 +08:00
lib	s390/mm: fix page table upgrade vs 2ndary address mode accesses	2021-03-16 16:27:05 +08:00
mm	s390/gmap: improve THP splitting	2021-03-16 16:33:57 +08:00
net	bpf: Introduce BPF nospec instruction for mitigating Spectre v4	2022-06-21 10:27:02 +08:00
numa	s390/numa: set node distance to LOCAL_DISTANCE	2021-03-16 16:34:56 +08:00
oprofile	Init Repo base on linux 5.4.32 long term, and add base tlinux kernel interfaces.	2021-03-16 11:01:34 +08:00
pci	s390/pci: Log new handle in clp_disable_fh()	2021-03-16 16:28:57 +08:00
purgatory	s390/kexec_file: fix diag308 subcode when loading crash kernel	2021-03-16 16:43:27 +08:00
scripts	Init Repo base on linux 5.4.32 long term, and add base tlinux kernel interfaces.	2021-03-16 11:01:34 +08:00
tools	Init Repo base on linux 5.4.32 long term, and add base tlinux kernel interfaces.	2021-03-16 11:01:34 +08:00
Kbuild	Init Repo base on linux 5.4.32 long term, and add base tlinux kernel interfaces.	2021-03-16 11:01:34 +08:00
Kconfig	Init Repo base on linux 5.4.32 long term, and add base tlinux kernel interfaces.	2021-03-16 11:01:34 +08:00
Kconfig.debug	Init Repo base on linux 5.4.32 long term, and add base tlinux kernel interfaces.	2021-03-16 11:01:34 +08:00
Makefile	Init Repo base on linux 5.4.32 long term, and add base tlinux kernel interfaces.	2021-03-16 11:01:34 +08:00