Merge https://git.kernel.org/pub/scm/linux/kernel/git/bpf/bpf-next

Daniel Borkmann says:

====================
pull-request: bpf-next 2021-01-16

1) Extend atomic operations to the BPF instruction set along with x86-64 JIT support,
   that is, atomic{,64}_{xchg,cmpxchg,fetch_{add,and,or,xor}}, from Brendan Jackman.

2) Add support for using kernel module global variables (__ksym externs in BPF
   programs) retrieved via module's BTF, from Andrii Nakryiko.

3) Generalize BPF stackmap's buildid retrieval and add support to have buildid
   stored in mmap2 event for perf, from Jiri Olsa.

4) Various fixes for cross-building BPF sefltests out-of-tree which then will
   unblock wider automated testing on ARM hardware, from Jean-Philippe Brucker.

5) Allow to retrieve SOL_SOCKET opts from sock_addr progs, from Daniel Borkmann.

6) Clean up driver's XDP buffer init and split into two helpers to init per-
   descriptor and non-changing fields during processing, from Lorenzo Bianconi.

7) Minor misc improvements to libbpf & bpftool, from Ian Rogers.

* https://git.kernel.org/pub/scm/linux/kernel/git/bpf/bpf-next: (41 commits)
  perf: Add build id data in mmap2 event
  bpf: Add size arg to build_id_parse function
  bpf: Move stack_map_get_build_id into lib
  bpf: Document new atomic instructions
  bpf: Add tests for new BPF atomic operations
  bpf: Add bitwise atomic instructions
  bpf: Pull out a macro for interpreting atomic ALU operations
  bpf: Add instructions for atomic_[cmp]xchg
  bpf: Add BPF_FETCH field / create atomic_fetch_add instruction
  bpf: Move BPF_STX reserved field check into BPF_STX verifier code
  bpf: Rename BPF_XADD and prepare to encode other atomics in .imm
  bpf: x86: Factor out a lookup table for some ALU opcodes
  bpf: x86: Factor out emission of REX byte
  bpf: x86: Factor out emission of ModR/M for *(reg + off)
  tools/bpftool: Add -Wall when building BPF programs
  bpf, libbpf: Avoid unused function warning on bpf_tail_call_static
  selftests/bpf: Install btf_dump test cases
  selftests/bpf: Fix installation of urandom_read
  selftests/bpf: Move generated test files to $(TEST_GEN_FILES)
  selftests/bpf: Fix out-of-tree build
  ...
====================

Link: https://lore.kernel.org/r/20210116012922.17823-1-daniel@iogearbox.net
Signed-off-by: Jakub Kicinski <kuba@kernel.org>

1 files changed, 16 insertions, 4 deletions

diff --git a/arch/riscv/net/bpf_jit_comp32.c b/arch/riscv/net/bpf_jit_comp32.c
index 579575f9cdae..81de865f4c7c 100644
--- a/arch/riscv/net/bpf_jit_comp32.c
+++ b/arch/riscv/net/bpf_jit_comp32.c
@@ -881,7 +881,7 @@ static int emit_store_r64(const s8 *dst, const s8 *src, s16 off,
 	const s8 *rd = bpf_get_reg64(dst, tmp1, ctx);
 	const s8 *rs = bpf_get_reg64(src, tmp2, ctx);
 
-	if (mode == BPF_XADD && size != BPF_W)
+	if (mode == BPF_ATOMIC && size != BPF_W)
 		return -1;
 
 	emit_imm(RV_REG_T0, off, ctx);
@@ -899,7 +899,7 @@ static int emit_store_r64(const s8 *dst, const s8 *src, s16 off,
 		case BPF_MEM:
 			emit(rv_sw(RV_REG_T0, 0, lo(rs)), ctx);
 			break;
-		case BPF_XADD:
+		case BPF_ATOMIC: /* Only BPF_ADD supported */
 			emit(rv_amoadd_w(RV_REG_ZERO, lo(rs), RV_REG_T0, 0, 0),
 			     ctx);
 			break;
@@ -1260,7 +1260,6 @@ int bpf_jit_emit_insn(const struct bpf_insn *insn, struct rv_jit_context *ctx,
 	case BPF_STX | BPF_MEM | BPF_H:
 	case BPF_STX | BPF_MEM | BPF_W:
 	case BPF_STX | BPF_MEM | BPF_DW:
-	case BPF_STX | BPF_XADD | BPF_W:
 		if (BPF_CLASS(code) == BPF_ST) {
 			emit_imm32(tmp2, imm, ctx);
 			src = tmp2;
@@ -1271,8 +1270,21 @@ int bpf_jit_emit_insn(const struct bpf_insn *insn, struct rv_jit_context *ctx,
 			return -1;
 		break;
 
+	case BPF_STX | BPF_ATOMIC | BPF_W:
+		if (insn->imm != BPF_ADD) {
+			pr_info_once(
+				"bpf-jit: not supported: atomic operation %02x ***\n",
+				insn->imm);
+			return -EFAULT;
+		}
+
+		if (emit_store_r64(dst, src, off, ctx, BPF_SIZE(code),
+				   BPF_MODE(code)))
+			return -1;
+		break;
+
 	/* No hardware support for 8-byte atomics in RV32. */
-	case BPF_STX | BPF_XADD | BPF_DW:
+	case BPF_STX | BPF_ATOMIC | BPF_DW:
 		/* Fallthrough. */
 
 notsupported: