For DADDI errata we just workaround by disable immediate operation for BPF_ADD / BPF_SUB to avoid generation of DADDIU. All other use cases in JIT won't cause overflow thus they are all safe. Signed-off-by: Jiaxun Yang <jiaxun.yang@xxxxxxxxxxx> --- v2: Drop 64BIT ifdef --- arch/mips/Kconfig | 1 - arch/mips/net/bpf_jit_comp.c | 4 ++++ 2 files changed, 4 insertions(+), 1 deletion(-) diff --git a/arch/mips/Kconfig b/arch/mips/Kconfig index 37072e15b263..df0910e3895c 100644 --- a/arch/mips/Kconfig +++ b/arch/mips/Kconfig @@ -64,7 +64,6 @@ config MIPS select HAVE_DMA_CONTIGUOUS select HAVE_DYNAMIC_FTRACE select HAVE_EBPF_JIT if !CPU_MICROMIPS && \ - !CPU_DADDI_WORKAROUNDS && \ !CPU_R4000_WORKAROUNDS && \ !CPU_R4400_WORKAROUNDS select HAVE_EXIT_THREAD diff --git a/arch/mips/net/bpf_jit_comp.c b/arch/mips/net/bpf_jit_comp.c index b17130d510d4..a40d926b6513 100644 --- a/arch/mips/net/bpf_jit_comp.c +++ b/arch/mips/net/bpf_jit_comp.c @@ -218,9 +218,13 @@ bool valid_alu_i(u8 op, s32 imm) /* All legal eBPF values are valid */ return true; case BPF_ADD: + if (IS_ENABLED(CONFIG_CPU_DADDI_WORKAROUNDS)) + return false; /* imm must be 16 bits */ return imm >= -0x8000 && imm <= 0x7fff; case BPF_SUB: + if (IS_ENABLED(CONFIG_CPU_DADDI_WORKAROUNDS)) + return false; /* -imm must be 16 bits */ return imm >= -0x7fff && imm <= 0x8000; case BPF_AND: -- 2.37.1 (Apple Git-137.1)
