linux - Linux Kernel (branches are rebased on master from time to time)

Age	Commit message (Collapse)	Author	Files	Lines
2022-12-14	LoongArch: BPF: Add BPF exception tables	Youling Tang	1	-5/+81
	Inspired by commit 800834285361("bpf, arm64: Add BPF exception tables"), do similar to LoongArch to add BPF exception tables. When a tracing BPF program attempts to read memory without using the bpf_probe_read() helper, the verifier marks the load instruction with the BPF_PROBE_MEM flag. Since the LoongArch JIT does not currently recognize this flag it falls back to the interpreter. Add support for BPF_PROBE_MEM, by appending an exception table to the BPF program. If the load instruction causes a data abort, the fixup infrastructure finds the exception table and fixes up the fault, by clearing the destination register and jumping over the faulting instruction. To keep the compact exception table entry format, inspect the pc in fixup_exception(). A more generic solution would add a "handler" field to the table entry, like on x86, s390 and arm64, etc. Signed-off-by: Youling Tang <tangyouling@loongson.cn> Signed-off-by: Huacai Chen <chenhuacai@loongson.cn>
2022-10-29	LoongArch: BPF: Avoid declare variables in switch-case	Huacai Chen	1	-18/+13
	Not all compilers support declare variables in switch-case, so move declarations to the beginning of a function. Otherwise we may get such build errors: arch/loongarch/net/bpf_jit.c: In function ‘emit_atomic’: arch/loongarch/net/bpf_jit.c:362:3: error: a label can only be part of a statement and a declaration is not a statement u8 r0 = regmap[BPF_REG_0]; ^~ arch/loongarch/net/bpf_jit.c: In function ‘build_insn’: arch/loongarch/net/bpf_jit.c:727:3: error: a label can only be part of a statement and a declaration is not a statement u8 t7 = -1; ^~ arch/loongarch/net/bpf_jit.c:778:3: error: a label can only be part of a statement and a declaration is not a statement int ret; ^~~ arch/loongarch/net/bpf_jit.c:779:3: error: expected expression before ‘u64’ u64 func_addr; ^~~ arch/loongarch/net/bpf_jit.c:780:3: warning: ISO C90 forbids mixed declarations and code [-Wdeclaration-after-statement] bool func_addr_fixed; ^~~~ arch/loongarch/net/bpf_jit.c:784:11: error: ‘func_addr’ undeclared (first use in this function); did you mean ‘in_addr’? &func_addr, &func_addr_fixed); ^~~~~~~~~ in_addr arch/loongarch/net/bpf_jit.c:784:11: note: each undeclared identifier is reported only once for each function it appears in arch/loongarch/net/bpf_jit.c:814:3: error: a label can only be part of a statement and a declaration is not a statement u64 imm64 = (u64)(insn + 1)->imm << 32 \| (u32)insn->imm; ^~~ Signed-off-by: Huacai Chen <chenhuacai@loongson.cn>
2022-10-12	LoongArch: Add BPF JIT support	Tiezhu Yang	1	-0/+1179
	BPF programs are normally handled by a BPF interpreter, add BPF JIT support for LoongArch to allow the kernel to generate native code when a program is loaded into the kernel. This will significantly speed-up processing of BPF programs. Co-developed-by: Youling Tang <tangyouling@loongson.cn> Signed-off-by: Youling Tang <tangyouling@loongson.cn> Signed-off-by: Tiezhu Yang <yangtiezhu@loongson.cn> Signed-off-by: Huacai Chen <chenhuacai@loongson.cn>