!70 BPF: Add CO-RE support for openEuler-22.09 v3

Merge Pull Request from: @zhengzengkai 
 
This set introduces CO-RE support in the kernel.
There are several reasons to add such support:
1. It's a step toward signed BPF programs.
2. It allows golang like languages that struggle to adopt libbpf
   to take advantage of CO-RE powers.
3. Currently the field accessed by 'ldx [R1 + 10]' insn is recognized
   by the verifier purely based on +10 offset. If R1 points to a union
   the verifier picks one of the fields at this offset.
   With CO-RE the kernel can disambiguate the field access. 
 
Link:https://gitee.com/openeuler/kernel/pulls/70 
Reviewed-by: Xie XiuQi <xiexiuqi@huawei.com> 
Signed-off-by: Xu Kuohai <xukuohai@huawei.com> 
Signed-off-by: Xie XiuQi <xiexiuqi@huawei.com> 

Documentation/ABI/testing/sysfs-kernel-btf

@@ -15,3 +15,11 @@ Description:
 		information with description of all internal kernel types. See
 		Documentation/bpf/btf.rst for detailed description of format
 		itself.
+
+What:		/sys/kernel/btf/<module-name>
+Date:		Nov 2020
+KernelVersion:	5.11
+Contact:	bpf@vger.kernel.org
+Description:
+		Read-only binary attribute exposing kernel module's BTF type
+		information as an add-on to the kernel's BTF (/sys/kernel/btf/vmlinux).

Documentation/bpf/btf.rst

@@ -84,6 +84,8 @@ sequentially and type id is assigned to each recognized type starting from id
     #define BTF_KIND_FUNC_PROTO     13      /* Function Proto       */
     #define BTF_KIND_VAR            14      /* Variable     */
     #define BTF_KIND_DATASEC        15      /* Section      */
+    #define BTF_KIND_DECL_TAG       17      /* Decl Tag     */
+    #define BTF_KIND_TYPE_TAG       18      /* Type Tag     */
 
 Note that the type section encodes debug info, not just pure types.
 ``BTF_KIND_FUNC`` is not a type, and it represents a defined subprogram.
@@ -105,7 +107,7 @@ Each type contains the following common data::
          * "size" tells the size of the type it is describing.
          *
          * "type" is used by PTR, TYPEDEF, VOLATILE, CONST, RESTRICT,
-         * FUNC and FUNC_PROTO.
+         * FUNC, FUNC_PROTO, DECL_TAG and TYPE_TAG.
          * "type" is a type_id referring to another type.
          */
         union {
@@ -452,6 +454,42 @@ map definition.
   * ``offset``: the in-section offset of the variable
   * ``size``: the size of the variable in bytes
 
+2.2.17 BTF_KIND_DECL_TAG
+~~~~~~~~~~~~~~~~~~~~~~~~
+
+``struct btf_type`` encoding requirement:
+ * ``name_off``: offset to a non-empty string
+ * ``info.kind_flag``: 0
+ * ``info.kind``: BTF_KIND_DECL_TAG
+ * ``info.vlen``: 0
+ * ``type``: ``struct``, ``union``, ``func``, ``var`` or ``typedef``
+
+``btf_type`` is followed by ``struct btf_decl_tag``.::
+
+    struct btf_decl_tag {
+        __u32   component_idx;
+    };
+
+The ``name_off`` encodes btf_decl_tag attribute string.
+The ``type`` should be ``struct``, ``union``, ``func``, ``var`` or ``typedef``.
+For ``var`` or ``typedef`` type, ``btf_decl_tag.component_idx`` must be ``-1``.
+For the other three types, if the btf_decl_tag attribute is
+applied to the ``struct``, ``union`` or ``func`` itself,
+``btf_decl_tag.component_idx`` must be ``-1``. Otherwise,
+the attribute is applied to a ``struct``/``union`` member or
+a ``func`` argument, and ``btf_decl_tag.component_idx`` should be a
+valid index (starting from 0) pointing to a member or an argument.
+
+2.2.17 BTF_KIND_TYPE_TAG
+~~~~~~~~~~~~~~~~~~~~~~~~
+
+``struct btf_type`` encoding requirement:
+ * ``name_off``: offset to a non-empty string
+ * ``info.kind_flag``: 0
+ * ``info.kind``: BTF_KIND_TYPE_TAG
+ * ``info.vlen``: 0
+ * ``type``: the type with ``btf_type_tag`` attribute
+
 3. BTF Kernel API
 *****************
 

Documentation/networking/filter.rst

@@ -1006,13 +1006,13 @@ Size modifier is one of ...
 
 Mode modifier is one of::
 
-  BPF_IMM  0x00  /* used for 32-bit mov in classic BPF and 64-bit in eBPF */
-  BPF_ABS  0x20
-  BPF_IND  0x40
-  BPF_MEM  0x60
-  BPF_LEN  0x80  /* classic BPF only, reserved in eBPF */
-  BPF_MSH  0xa0  /* classic BPF only, reserved in eBPF */
-  BPF_XADD 0xc0  /* eBPF only, exclusive add */
+  BPF_IMM     0x00  /* used for 32-bit mov in classic BPF and 64-bit in eBPF */
+  BPF_ABS     0x20
+  BPF_IND     0x40
+  BPF_MEM     0x60
+  BPF_LEN     0x80  /* classic BPF only, reserved in eBPF */
+  BPF_MSH     0xa0  /* classic BPF only, reserved in eBPF */
+  BPF_ATOMIC  0xc0  /* eBPF only, atomic operations */
 
 eBPF has two non-generic instructions: (BPF_ABS | <size> | BPF_LD) and
 (BPF_IND | <size> | BPF_LD) which are used to access packet data.
@@ -1044,11 +1044,50 @@ Unlike classic BPF instruction set, eBPF has generic load/store operations::
     BPF_MEM | <size> | BPF_STX:  *(size *) (dst_reg + off) = src_reg
     BPF_MEM | <size> | BPF_ST:   *(size *) (dst_reg + off) = imm32
     BPF_MEM | <size> | BPF_LDX:  dst_reg = *(size *) (src_reg + off)
-    BPF_XADD | BPF_W  | BPF_STX: lock xadd *(u32 *)(dst_reg + off16) += src_reg
-    BPF_XADD | BPF_DW | BPF_STX: lock xadd *(u64 *)(dst_reg + off16) += src_reg
 
-Where size is one of: BPF_B or BPF_H or BPF_W or BPF_DW. Note that 1 and
-2 byte atomic increments are not supported.
+Where size is one of: BPF_B or BPF_H or BPF_W or BPF_DW.
+
+It also includes atomic operations, which use the immediate field for extra
+encoding.
+
+   .imm = BPF_ADD, .code = BPF_ATOMIC | BPF_W  | BPF_STX: lock xadd *(u32 *)(dst_reg + off16) += src_reg
+   .imm = BPF_ADD, .code = BPF_ATOMIC | BPF_DW | BPF_STX: lock xadd *(u64 *)(dst_reg + off16) += src_reg
+
+The basic atomic operations supported are:
+
+    BPF_ADD
+    BPF_AND
+    BPF_OR
+    BPF_XOR
+
+Each having equivalent semantics with the ``BPF_ADD`` example, that is: the
+memory location addresed by ``dst_reg + off`` is atomically modified, with
+``src_reg`` as the other operand. If the ``BPF_FETCH`` flag is set in the
+immediate, then these operations also overwrite ``src_reg`` with the
+value that was in memory before it was modified.
+
+The more special operations are:
+
+    BPF_XCHG
+
+This atomically exchanges ``src_reg`` with the value addressed by ``dst_reg +
+off``.
+
+    BPF_CMPXCHG
+
+This atomically compares the value addressed by ``dst_reg + off`` with
+``R0``. If they match it is replaced with ``src_reg``, The value that was there
+before is loaded back to ``R0``.
+
+Note that 1 and 2 byte atomic operations are not supported.
+
+Except ``BPF_ADD`` _without_ ``BPF_FETCH`` (for legacy reasons), all 4 byte
+atomic operations require alu32 mode. Clang enables this mode by default in
+architecture v3 (``-mcpu=v3``). For older versions it can be enabled with
+``-Xclang -target-feature -Xclang +alu32``.
+
+You may encounter BPF_XADD - this is a legacy name for BPF_ATOMIC, referring to
+the exclusive-add operation encoded when the immediate field is zero.
 
 eBPF has one 16-byte instruction: BPF_LD | BPF_DW | BPF_IMM which consists
 of two consecutive ``struct bpf_insn`` 8-byte blocks and interpreted as single

arch/arm/net/bpf_jit_32.c

@@ -1642,10 +1642,9 @@ static int build_insn(const struct bpf_insn *insn, struct jit_ctx *ctx)
 		}
 		emit_str_r(dst_lo, tmp2, off, ctx, BPF_SIZE(code));
 		break;
-	/* STX XADD: lock *(u32 *)(dst + off) += src */
-	case BPF_STX | BPF_XADD | BPF_W:
-	/* STX XADD: lock *(u64 *)(dst + off) += src */
-	case BPF_STX | BPF_XADD | BPF_DW:
+	/* Atomic ops */
+	case BPF_STX | BPF_ATOMIC | BPF_W:
+	case BPF_STX | BPF_ATOMIC | BPF_DW:
 		goto notyet;
 	/* STX: *(size *)(dst + off) = src */
 	case BPF_STX | BPF_MEM | BPF_W:

arch/arm64/net/bpf_jit_comp.c

@@ -888,10 +888,18 @@ static int build_insn(const struct bpf_insn *insn, struct jit_ctx *ctx,
 		}
 		break;
 
-	/* STX XADD: lock *(u32 *)(dst + off) += src */
-	case BPF_STX | BPF_XADD | BPF_W:
-	/* STX XADD: lock *(u64 *)(dst + off) += src */
-	case BPF_STX | BPF_XADD | BPF_DW:
+	case BPF_STX | BPF_ATOMIC | BPF_W:
+	case BPF_STX | BPF_ATOMIC | BPF_DW:
+		if (insn->imm != BPF_ADD) {
+			pr_err_once("unknown atomic op code %02x\n", insn->imm);
+			return -EINVAL;
+		}
+
+		/* STX XADD: lock *(u32 *)(dst + off) += src
+		 * and
+		 * STX XADD: lock *(u64 *)(dst + off) += src
+		 */
+
 		if (!off) {
 			reg = dst;
 		} else {

arch/mips/net/ebpf_jit.c

@@ -1426,8 +1426,8 @@ static int build_one_insn(const struct bpf_insn *insn, struct jit_ctx *ctx,
 	case BPF_STX | BPF_H | BPF_MEM:
 	case BPF_STX | BPF_W | BPF_MEM:
 	case BPF_STX | BPF_DW | BPF_MEM:
-	case BPF_STX | BPF_W | BPF_XADD:
-	case BPF_STX | BPF_DW | BPF_XADD:
+	case BPF_STX | BPF_W | BPF_ATOMIC:
+	case BPF_STX | BPF_DW | BPF_ATOMIC:
 		if (insn->dst_reg == BPF_REG_10) {
 			ctx->flags |= EBPF_SEEN_FP;
 			dst = MIPS_R_SP;
@@ -1441,7 +1441,12 @@ static int build_one_insn(const struct bpf_insn *insn, struct jit_ctx *ctx,
 		src = ebpf_to_mips_reg(ctx, insn, src_reg_no_fp);
 		if (src < 0)
 			return src;
-		if (BPF_MODE(insn->code) == BPF_XADD) {
+		if (BPF_MODE(insn->code) == BPF_ATOMIC) {
+			if (insn->imm != BPF_ADD) {
+				pr_err("ATOMIC OP %02x NOT HANDLED\n", insn->imm);
+				return -EINVAL;
+			}
+
 			/*
 			 * If mem_off does not fit within the 9 bit ll/sc
 			 * instruction immediate field, use a temp reg.

arch/powerpc/net/bpf_jit_comp64.c

@@ -756,10 +756,18 @@ static int bpf_jit_build_body(struct bpf_prog *fp, u32 *image,
 			break;
 
 		/*
-		 * BPF_STX XADD (atomic_add)
+		 * BPF_STX ATOMIC (atomic ops)
 		 */
-		/* *(u32 *)(dst + off) += src */
-		case BPF_STX | BPF_XADD | BPF_W:
+		case BPF_STX | BPF_ATOMIC | BPF_W:
+			if (insn->imm != BPF_ADD) {
+				pr_err_ratelimited(
+					"eBPF filter atomic op code %02x (@%d) unsupported\n",
+					code, i);
+				return -ENOTSUPP;
+			}
+
+			/* *(u32 *)(dst + off) += src */
+
 			/* Get EA into TMP_REG_1 */
 			EMIT(PPC_RAW_ADDI(b2p[TMP_REG_1], dst_reg, off));
 			tmp_idx = ctx->idx * 4;
@@ -772,8 +780,15 @@ static int bpf_jit_build_body(struct bpf_prog *fp, u32 *image,
 			/* we're done if this succeeded */
 			PPC_BCC_SHORT(COND_NE, tmp_idx);
 			break;
-		/* *(u64 *)(dst + off) += src */
-		case BPF_STX | BPF_XADD | BPF_DW:
+		case BPF_STX | BPF_ATOMIC | BPF_DW:
+			if (insn->imm != BPF_ADD) {
+				pr_err_ratelimited(
+					"eBPF filter atomic op code %02x (@%d) unsupported\n",
+					code, i);
+				return -ENOTSUPP;
+			}
+			/* *(u64 *)(dst + off) += src */
+
 			EMIT(PPC_RAW_ADDI(b2p[TMP_REG_1], dst_reg, off));
 			tmp_idx = ctx->idx * 4;
 			EMIT(PPC_RAW_LDARX(b2p[TMP_REG_2], 0, b2p[TMP_REG_1], 0));

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;
@@ -1264,7 +1264,6 @@ 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;
@@ -1275,8 +1274,21 @@ 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:

arch/riscv/net/bpf_jit_comp64.c

@@ -1031,10 +1031,18 @@ int bpf_jit_emit_insn(const struct bpf_insn *insn, struct rv_jit_context *ctx,
 		emit_add(RV_REG_T1, RV_REG_T1, rd, ctx);
 		emit_sd(RV_REG_T1, 0, rs, ctx);
 		break;
-	/* STX XADD: lock *(u32 *)(dst + off) += src */
-	case BPF_STX | BPF_XADD | BPF_W:
-	/* STX XADD: lock *(u64 *)(dst + off) += src */
-	case BPF_STX | BPF_XADD | BPF_DW:
+	case BPF_STX | BPF_ATOMIC | BPF_W:
+	case BPF_STX | BPF_ATOMIC | BPF_DW:
+		if (insn->imm != BPF_ADD) {
+			pr_err("bpf-jit: not supported: atomic operation %02x ***\n",
+			       insn->imm);
+			return -EINVAL;
+		}
+
+		/* atomic_add: lock *(u32 *)(dst + off) += src
+		 * atomic_add: lock *(u64 *)(dst + off) += src
+		 */
+
 		if (off) {
 			if (is_12b_int(off)) {
 				emit_addi(RV_REG_T1, rd, off, ctx);

arch/s390/net/bpf_jit_comp.c

@@ -1216,18 +1216,23 @@ static noinline int bpf_jit_insn(struct bpf_jit *jit, struct bpf_prog *fp,
 		jit->seen |= SEEN_MEM;
 		break;
 	/*
-	 * BPF_STX XADD (atomic_add)
+	 * BPF_ATOMIC
 	 */
-	case BPF_STX | BPF_XADD | BPF_W: /* *(u32 *)(dst + off) += src */
-		/* laal %w0,%src,off(%dst) */
-		EMIT6_DISP_LH(0xeb000000, 0x00fa, REG_W0, src_reg,
-			      dst_reg, off);
-		jit->seen |= SEEN_MEM;
-		break;
-	case BPF_STX | BPF_XADD | BPF_DW: /* *(u64 *)(dst + off) += src */
-		/* laalg %w0,%src,off(%dst) */
-		EMIT6_DISP_LH(0xeb000000, 0x00ea, REG_W0, src_reg,
-			      dst_reg, off);
+	case BPF_STX | BPF_ATOMIC | BPF_DW:
+	case BPF_STX | BPF_ATOMIC | BPF_W:
+		if (insn->imm != BPF_ADD) {
+			pr_err("Unknown atomic operation %02x\n", insn->imm);
+			return -1;
+		}
+
+		/* *(u32/u64 *)(dst + off) += src
+		 *
+		 * BFW_W:  laal  %w0,%src,off(%dst)
+		 * BPF_DW: laalg %w0,%src,off(%dst)
+		 */
+		EMIT6_DISP_LH(0xeb000000,
+			      BPF_SIZE(insn->code) == BPF_W ? 0x00fa : 0x00ea,
+			      REG_W0, src_reg, dst_reg, off);
 		jit->seen |= SEEN_MEM;
 		break;
 	/*

arch/sparc/net/bpf_jit_comp_64.c

@@ -1369,12 +1369,18 @@ static int build_insn(const struct bpf_insn *insn, struct jit_ctx *ctx)
 		break;
 	}
 
-	/* STX XADD: lock *(u32 *)(dst + off) += src */
-	case BPF_STX | BPF_XADD | BPF_W: {
+	case BPF_STX | BPF_ATOMIC | BPF_W: {
 		const u8 tmp = bpf2sparc[TMP_REG_1];
 		const u8 tmp2 = bpf2sparc[TMP_REG_2];
 		const u8 tmp3 = bpf2sparc[TMP_REG_3];
 
+		if (insn->imm != BPF_ADD) {
+			pr_err_once("unknown atomic op %02x\n", insn->imm);
+			return -EINVAL;
+		}
+
+		/* lock *(u32 *)(dst + off) += src */
+
 		if (insn->dst_reg == BPF_REG_FP)
 			ctx->saw_frame_pointer = true;
 
@@ -1393,11 +1399,16 @@ static int build_insn(const struct bpf_insn *insn, struct jit_ctx *ctx)
 		break;
 	}
 	/* STX XADD: lock *(u64 *)(dst + off) += src */
-	case BPF_STX | BPF_XADD | BPF_DW: {
+	case BPF_STX | BPF_ATOMIC | BPF_DW: {
 		const u8 tmp = bpf2sparc[TMP_REG_1];
 		const u8 tmp2 = bpf2sparc[TMP_REG_2];
 		const u8 tmp3 = bpf2sparc[TMP_REG_3];
 
+		if (insn->imm != BPF_ADD) {
+			pr_err_once("unknown atomic op %02x\n", insn->imm);
+			return -EINVAL;
+		}
+
 		if (insn->dst_reg == BPF_REG_FP)
 			ctx->saw_frame_pointer = true;
 

arch/x86/net/bpf_jit_comp.c

@@ -205,6 +205,18 @@ static u8 add_2reg(u8 byte, u32 dst_reg, u32 src_reg)
 	return byte + reg2hex[dst_reg] + (reg2hex[src_reg] << 3);
 }
 
+/* Some 1-byte opcodes for binary ALU operations */
+static u8 simple_alu_opcodes[] = {
+	[BPF_ADD] = 0x01,
+	[BPF_SUB] = 0x29,
+	[BPF_AND] = 0x21,
+	[BPF_OR] = 0x09,
+	[BPF_XOR] = 0x31,
+	[BPF_LSH] = 0xE0,
+	[BPF_RSH] = 0xE8,
+	[BPF_ARSH] = 0xF8,
+};
+
 static void jit_fill_hole(void *area, unsigned int size)
 {
 	/* Fill whole space with INT3 instructions */
@@ -684,6 +696,42 @@ static void emit_mov_reg(u8 **pprog, bool is64, u32 dst_reg, u32 src_reg)
 	*pprog = prog;
 }
 
+/* Emit the suffix (ModR/M etc) for addressing *(ptr_reg + off) and val_reg */
+static void emit_insn_suffix(u8 **pprog, u32 ptr_reg, u32 val_reg, int off)
+{
+	u8 *prog = *pprog;
+	int cnt = 0;
+
+	if (is_imm8(off)) {
+		/* 1-byte signed displacement.
+		 *
+		 * If off == 0 we could skip this and save one extra byte, but
+		 * special case of x86 R13 which always needs an offset is not
+		 * worth the hassle
+		 */
+		EMIT2(add_2reg(0x40, ptr_reg, val_reg), off);
+	} else {
+		/* 4-byte signed displacement */
+		EMIT1_off32(add_2reg(0x80, ptr_reg, val_reg), off);
+	}
+	*pprog = prog;
+}
+
+/*
+ * Emit a REX byte if it will be necessary to address these registers
+ */
+static void maybe_emit_mod(u8 **pprog, u32 dst_reg, u32 src_reg, bool is64)
+{
+	u8 *prog = *pprog;
+	int cnt = 0;
+
+	if (is64)
+		EMIT1(add_2mod(0x48, dst_reg, src_reg));
+	else if (is_ereg(dst_reg) || is_ereg(src_reg))
+		EMIT1(add_2mod(0x40, dst_reg, src_reg));
+	*pprog = prog;
+}
+
 /* LDX: dst_reg = *(u8*)(src_reg + off) */
 static void emit_ldx(u8 **pprog, u32 size, u32 dst_reg, u32 src_reg, int off)
 {
@@ -711,15 +759,7 @@ static void emit_ldx(u8 **pprog, u32 size, u32 dst_reg, u32 src_reg, int off)
 		EMIT2(add_2mod(0x48, src_reg, dst_reg), 0x8B);
 		break;
 	}
-	/*
-	 * If insn->off == 0 we can save one extra byte, but
-	 * special case of x86 R13 which always needs an offset
-	 * is not worth the hassle
-	 */
-	if (is_imm8(off))
-		EMIT2(add_2reg(0x40, src_reg, dst_reg), off);
-	else
-		EMIT1_off32(add_2reg(0x80, src_reg, dst_reg), off);
+	emit_insn_suffix(&prog, src_reg, dst_reg, off);
 	*pprog = prog;
 }
 
@@ -754,11 +794,51 @@ static void emit_stx(u8 **pprog, u32 size, u32 dst_reg, u32 src_reg, int off)
 		EMIT2(add_2mod(0x48, dst_reg, src_reg), 0x89);
 		break;
 	}
-	if (is_imm8(off))
-		EMIT2(add_2reg(0x40, dst_reg, src_reg), off);
-	else
-		EMIT1_off32(add_2reg(0x80, dst_reg, src_reg), off);
+	emit_insn_suffix(&prog, dst_reg, src_reg, off);
+	*pprog = prog;
+}
+
+static int emit_atomic(u8 **pprog, u8 atomic_op,
+		       u32 dst_reg, u32 src_reg, s16 off, u8 bpf_size)
+{
+	u8 *prog = *pprog;
+	int cnt = 0;
+
+	EMIT1(0xF0); /* lock prefix */
+
+	maybe_emit_mod(&prog, dst_reg, src_reg, bpf_size == BPF_DW);
+
+	/* emit opcode */
+	switch (atomic_op) {
+	case BPF_ADD:
+	case BPF_SUB:
+	case BPF_AND:
+	case BPF_OR:
+	case BPF_XOR:
+		/* lock *(u32/u64*)(dst_reg + off) <op>= src_reg */
+		EMIT1(simple_alu_opcodes[atomic_op]);
+		break;
+	case BPF_ADD | BPF_FETCH:
+		/* src_reg = atomic_fetch_add(dst_reg + off, src_reg); */
+		EMIT2(0x0F, 0xC1);
+		break;
+	case BPF_XCHG:
+		/* src_reg = atomic_xchg(dst_reg + off, src_reg); */
+		EMIT1(0x87);
+		break;
+	case BPF_CMPXCHG:
+		/* r0 = atomic_cmpxchg(dst_reg + off, r0, src_reg); */
+		EMIT2(0x0F, 0xB1);
+		break;
+	default:
+		pr_err("bpf_jit: unknown atomic opcode %02x\n", atomic_op);
+		return -EFAULT;
+	}
+
+	emit_insn_suffix(&prog, dst_reg, src_reg, off);
+
 	*pprog = prog;
+	return 0;
 }
 
 bool ex_handler_bpf(const struct exception_table_entry *x, struct pt_regs *regs)
@@ -790,8 +870,31 @@ static void detect_reg_usage(struct bpf_insn *insn, int insn_cnt,
 	}
 }
 
+static int emit_nops(u8 **pprog, int len)
+{
+	u8 *prog = *pprog;
+	int i, noplen, cnt = 0;
+
+	while (len > 0) {
+		noplen = len;
+
+		if (noplen > ASM_NOP_MAX)
+			noplen = ASM_NOP_MAX;
+
+		for (i = 0; i < noplen; i++)
+			EMIT1(ideal_nops[noplen][i]);
+		len -= noplen;
+	}
+
+	*pprog = prog;
+
+	return cnt;
+}
+
+#define INSN_SZ_DIFF (((addrs[i] - addrs[i - 1]) - (prog - temp)))
+
 static int do_jit(struct bpf_prog *bpf_prog, int *addrs, u8 *image,
-		  int oldproglen, struct jit_context *ctx)
+		  int oldproglen, struct jit_context *ctx, bool jmp_padding)
 {
 	bool tail_call_reachable = bpf_prog->aux->tail_call_reachable;
 	struct bpf_insn *insn = bpf_prog->insnsi;
@@ -801,8 +904,9 @@ static int do_jit(struct bpf_prog *bpf_prog, int *addrs, u8 *image,
 	bool seen_exit = false;
 	u8 temp[BPF_MAX_INSN_SIZE + BPF_INSN_SAFETY];
 	int i, cnt = 0, excnt = 0;
-	int proglen = 0;
+	int ilen, proglen = 0;
 	u8 *prog = temp;
+	int err;
 
 	detect_reg_usage(insn, insn_cnt, callee_regs_used,
 			 &tail_call_seen);
@@ -814,7 +918,13 @@ static int do_jit(struct bpf_prog *bpf_prog, int *addrs, u8 *image,
 		      bpf_prog_was_classic(bpf_prog), tail_call_reachable,
 		      bpf_prog->aux->func_idx != 0);
 	push_callee_regs(&prog, callee_regs_used);
-	addrs[0] = prog - temp;
+
+	ilen = prog - temp;
+	if (image)
+		memcpy(image + proglen, temp, ilen);
+	proglen += ilen;
+	addrs[0] = proglen;
+	prog = temp;
 
 	for (i = 1; i <= insn_cnt; i++, insn++) {
 		const s32 imm32 = insn->imm;
@@ -823,8 +933,8 @@ static int do_jit(struct bpf_prog *bpf_prog, int *addrs, u8 *image,
 		u8 b2 = 0, b3 = 0;
 		s64 jmp_offset;
 		u8 jmp_cond;
-		int ilen;
 		u8 *func;
+		int nops;
 
 		switch (insn->code) {
 			/* ALU */
@@ -838,17 +948,9 @@ static int do_jit(struct bpf_prog *bpf_prog, int *addrs, u8 *image,
 		case BPF_ALU64 | BPF_AND | BPF_X:
 		case BPF_ALU64 | BPF_OR | BPF_X:
 		case BPF_ALU64 | BPF_XOR | BPF_X:
-			switch (BPF_OP(insn->code)) {
-			case BPF_ADD: b2 = 0x01; break;
-			case BPF_SUB: b2 = 0x29; break;
-			case BPF_AND: b2 = 0x21; break;
-			case BPF_OR: b2 = 0x09; break;
-			case BPF_XOR: b2 = 0x31; break;
-			}
-			if (BPF_CLASS(insn->code) == BPF_ALU64)
-				EMIT1(add_2mod(0x48, dst_reg, src_reg));
-			else if (is_ereg(dst_reg) || is_ereg(src_reg))
-				EMIT1(add_2mod(0x40, dst_reg, src_reg));
+			maybe_emit_mod(&prog, dst_reg, src_reg,
+				       BPF_CLASS(insn->code) == BPF_ALU64);
+			b2 = simple_alu_opcodes[BPF_OP(insn->code)];
 			EMIT2(b2, add_2reg(0xC0, dst_reg, src_reg));
 			break;
 
@@ -1028,12 +1130,7 @@ static int do_jit(struct bpf_prog *bpf_prog, int *addrs, u8 *image,
 			else if (is_ereg(dst_reg))
 				EMIT1(add_1mod(0x40, dst_reg));
 
-			switch (BPF_OP(insn->code)) {
-			case BPF_LSH: b3 = 0xE0; break;
-			case BPF_RSH: b3 = 0xE8; break;
-			case BPF_ARSH: b3 = 0xF8; break;
-			}
-
+			b3 = simple_alu_opcodes[BPF_OP(insn->code)];
 			if (imm32 == 1)
 				EMIT2(0xD1, add_1reg(b3, dst_reg));
 			else
@@ -1067,11 +1164,7 @@ static int do_jit(struct bpf_prog *bpf_prog, int *addrs, u8 *image,
 			else if (is_ereg(dst_reg))
 				EMIT1(add_1mod(0x40, dst_reg));
 
-			switch (BPF_OP(insn->code)) {
-			case BPF_LSH: b3 = 0xE0; break;
-			case BPF_RSH: b3 = 0xE8; break;
-			case BPF_ARSH: b3 = 0xF8; break;
-			}
+			b3 = simple_alu_opcodes[BPF_OP(insn->code)];
 			EMIT2(0xD3, add_1reg(b3, dst_reg));
 
 			if (src_reg != BPF_REG_4)
@@ -1233,21 +1326,56 @@ st:			if (is_imm8(insn->off))
 			}
 			break;
 
-			/* STX XADD: lock *(u32*)(dst_reg + off) += src_reg */
-		case BPF_STX | BPF_XADD | BPF_W:
-			/* Emit 'lock add dword ptr [rax + off], eax' */
-			if (is_ereg(dst_reg) || is_ereg(src_reg))
-				EMIT3(0xF0, add_2mod(0x40, dst_reg, src_reg), 0x01);
-			else
-				EMIT2(0xF0, 0x01);
-			goto xadd;
-		case BPF_STX | BPF_XADD | BPF_DW:
-			EMIT3(0xF0, add_2mod(0x48, dst_reg, src_reg), 0x01);
-xadd:			if (is_imm8(insn->off))
-				EMIT2(add_2reg(0x40, dst_reg, src_reg), insn->off);
-			else
-				EMIT1_off32(add_2reg(0x80, dst_reg, src_reg),
-					    insn->off);
+		case BPF_STX | BPF_ATOMIC | BPF_W:
+		case BPF_STX | BPF_ATOMIC | BPF_DW:
+			if (insn->imm == (BPF_AND | BPF_FETCH) ||
+			    insn->imm == (BPF_OR | BPF_FETCH) ||
+			    insn->imm == (BPF_XOR | BPF_FETCH)) {
+				u8 *branch_target;
+				bool is64 = BPF_SIZE(insn->code) == BPF_DW;
+
+				/*
+				 * Can't be implemented with a single x86 insn.
+				 * Need to do a CMPXCHG loop.
+				 */
+
+				/* Will need RAX as a CMPXCHG operand so save R0 */
+				emit_mov_reg(&prog, true, BPF_REG_AX, BPF_REG_0);
+				branch_target = prog;
+				/* Load old value */
+				emit_ldx(&prog, BPF_SIZE(insn->code),
+					 BPF_REG_0, dst_reg, insn->off);
+				/*
+				 * Perform the (commutative) operation locally,
+				 * put the result in the AUX_REG.
+				 */
+				emit_mov_reg(&prog, is64, AUX_REG, BPF_REG_0);
+				maybe_emit_mod(&prog, AUX_REG, src_reg, is64);
+				EMIT2(simple_alu_opcodes[BPF_OP(insn->imm)],
+				      add_2reg(0xC0, AUX_REG, src_reg));
+				/* Attempt to swap in new value */
+				err = emit_atomic(&prog, BPF_CMPXCHG,
+						  dst_reg, AUX_REG, insn->off,
+						  BPF_SIZE(insn->code));
+				if (WARN_ON(err))
+					return err;
+				/*
+				 * ZF tells us whether we won the race. If it's
+				 * cleared we need to try again.
+				 */
+				EMIT2(X86_JNE, -(prog - branch_target) - 2);
+				/* Return the pre-modification value */
+				emit_mov_reg(&prog, is64, src_reg, BPF_REG_0);
+				/* Restore R0 after clobbering RAX */
+				emit_mov_reg(&prog, true, BPF_REG_0, BPF_REG_AX);
+				break;
+
+			}
+
+			err = emit_atomic(&prog, insn->imm, dst_reg, src_reg,
+						  insn->off, BPF_SIZE(insn->code));
+			if (err)
+				return err;
 			break;
 
 			/* call */
@@ -1298,20 +1426,16 @@ xadd:			if (is_imm8(insn->off))
 		case BPF_JMP32 | BPF_JSGE | BPF_X:
 		case BPF_JMP32 | BPF_JSLE | BPF_X:
 			/* cmp dst_reg, src_reg */
-			if (BPF_CLASS(insn->code) == BPF_JMP)
-				EMIT1(add_2mod(0x48, dst_reg, src_reg));
-			else if (is_ereg(dst_reg) || is_ereg(src_reg))
-				EMIT1(add_2mod(0x40, dst_reg, src_reg));
+			maybe_emit_mod(&prog, dst_reg, src_reg,
+				       BPF_CLASS(insn->code) == BPF_JMP);
 			EMIT2(0x39, add_2reg(0xC0, dst_reg, src_reg));
 			goto emit_cond_jmp;
 
 		case BPF_JMP | BPF_JSET | BPF_X:
 		case BPF_JMP32 | BPF_JSET | BPF_X:
 			/* test dst_reg, src_reg */
-			if (BPF_CLASS(insn->code) == BPF_JMP)
-				EMIT1(add_2mod(0x48, dst_reg, src_reg));
-			else if (is_ereg(dst_reg) || is_ereg(src_reg))
-				EMIT1(add_2mod(0x40, dst_reg, src_reg));
+			maybe_emit_mod(&prog, dst_reg, src_reg,
+				       BPF_CLASS(insn->code) == BPF_JMP);
 			EMIT2(0x85, add_2reg(0xC0, dst_reg, src_reg));
 			goto emit_cond_jmp;
 
@@ -1347,10 +1471,8 @@ xadd:			if (is_imm8(insn->off))
 		case BPF_JMP32 | BPF_JSLE | BPF_K:
 			/* test dst_reg, dst_reg to save one extra byte */
 			if (imm32 == 0) {
-				if (BPF_CLASS(insn->code) == BPF_JMP)
-					EMIT1(add_2mod(0x48, dst_reg, dst_reg));
-				else if (is_ereg(dst_reg))
-					EMIT1(add_2mod(0x40, dst_reg, dst_reg));
+				maybe_emit_mod(&prog, dst_reg, dst_reg,
+					       BPF_CLASS(insn->code) == BPF_JMP);
 				EMIT2(0x85, add_2reg(0xC0, dst_reg, dst_reg));
 				goto emit_cond_jmp;
 			}
@@ -1412,6 +1534,30 @@ xadd:			if (is_imm8(insn->off))
 			}
 			jmp_offset = addrs[i + insn->off] - addrs[i];
 			if (is_imm8(jmp_offset)) {
+				if (jmp_padding) {
+					/* To keep the jmp_offset valid, the extra bytes are
+					 * padded before the jump insn, so we substract the
+					 * 2 bytes of jmp_cond insn from INSN_SZ_DIFF.
+					 *
+					 * If the previous pass already emits an imm8
+					 * jmp_cond, then this BPF insn won't shrink, so
+					 * "nops" is 0.
+					 *
+					 * On the other hand, if the previous pass emits an
+					 * imm32 jmp_cond, the extra 4 bytes(*) is padded to
+					 * keep the image from shrinking further.
+					 *
+					 * (*) imm32 jmp_cond is 6 bytes, and imm8 jmp_cond
+					 *     is 2 bytes, so the size difference is 4 bytes.
+					 */
+					nops = INSN_SZ_DIFF - 2;
+					if (nops != 0 && nops != 4) {
+						pr_err("unexpected jmp_cond padding: %d bytes\n",
+						       nops);
+						return -EFAULT;
+					}
+					cnt += emit_nops(&prog, nops);
+				}
 				EMIT2(jmp_cond, jmp_offset);
 			} else if (is_simm32(jmp_offset)) {
 				EMIT2_off32(0x0F, jmp_cond + 0x10, jmp_offset);
@@ -1434,11 +1580,55 @@ xadd:			if (is_imm8(insn->off))
 			else
 				jmp_offset = addrs[i + insn->off] - addrs[i];
 
-			if (!jmp_offset)
-				/* Optimize out nop jumps */
+			if (!jmp_offset) {
+				/*
+				 * If jmp_padding is enabled, the extra nops will
+				 * be inserted. Otherwise, optimize out nop jumps.
+				 */
+				if (jmp_padding) {
+					/* There are 3 possible conditions.
+					 * (1) This BPF_JA is already optimized out in
+					 *     the previous run, so there is no need
+					 *     to pad any extra byte (0 byte).
+					 * (2) The previous pass emits an imm8 jmp,
+					 *     so we pad 2 bytes to match the previous
+					 *     insn size.
+					 * (3) Similarly, the previous pass emits an
+					 *     imm32 jmp, and 5 bytes is padded.
+					 */
+					nops = INSN_SZ_DIFF;
+					if (nops != 0 && nops != 2 && nops != 5) {
+						pr_err("unexpected nop jump padding: %d bytes\n",
+						       nops);
+						return -EFAULT;
+					}
+					cnt += emit_nops(&prog, nops);
+				}
 				break;
+			}
 emit_jmp:
 			if (is_imm8(jmp_offset)) {
+				if (jmp_padding) {
+					/* To avoid breaking jmp_offset, the extra bytes
+					 * are padded before the actual jmp insn, so
+					 * 2 bytes is substracted from INSN_SZ_DIFF.
+					 *
+					 * If the previous pass already emits an imm8
+					 * jmp, there is nothing to pad (0 byte).
+					 *
+					 * If it emits an imm32 jmp (5 bytes) previously
+					 * and now an imm8 jmp (2 bytes), then we pad
+					 * (5 - 2 = 3) bytes to stop the image from
+					 * shrinking further.
+					 */
+					nops = INSN_SZ_DIFF - 2;
+					if (nops != 0 && nops != 3) {
+						pr_err("unexpected jump padding: %d bytes\n",
+						       nops);
+						return -EFAULT;
+					}
+					cnt += emit_nops(&prog, INSN_SZ_DIFF - 2);
+				}
 				EMIT2(0xEB, jmp_offset);
 			} else if (is_simm32(jmp_offset)) {
 				EMIT1_off32(0xE9, jmp_offset);
@@ -1543,17 +1733,25 @@ static int invoke_bpf_prog(const struct btf_func_model *m, u8 **pprog,
 			   struct bpf_prog *p, int stack_size, bool save_ret)
 {
 	u8 *prog = *pprog;
+	u8 *jmp_insn;
 	int cnt = 0;
 
-	if (p->aux->sleepable) {
-		if (emit_call(&prog, __bpf_prog_enter_sleepable, prog))
+	/* arg1: mov rdi, progs[i] */
+	emit_mov_imm64(&prog, BPF_REG_1, (long) p >> 32, (u32) (long) p);
+	if (emit_call(&prog,
+		      p->aux->sleepable ? __bpf_prog_enter_sleepable :
+		      __bpf_prog_enter, prog))
 			return -EINVAL;
-	} else {
-		if (emit_call(&prog, __bpf_prog_enter, prog))
-			return -EINVAL;
-		/* remember prog start time returned by __bpf_prog_enter */
-		emit_mov_reg(&prog, true, BPF_REG_6, BPF_REG_0);
-	}
+	/* remember prog start time returned by __bpf_prog_enter */
+	emit_mov_reg(&prog, true, BPF_REG_6, BPF_REG_0);
+
+	/* if (__bpf_prog_enter*(prog) == 0)
+	 *	goto skip_exec_of_prog;
+	 */
+	EMIT3(0x48, 0x85, 0xC0);  /* test rax,rax */
+	/* emit 2 nops that will be replaced with JE insn */
+	jmp_insn = prog;
+	emit_nops(&prog, 2);
 
 	/* arg1: lea rdi, [rbp - stack_size] */
 	EMIT4(0x48, 0x8D, 0x7D, -stack_size);
@@ -1577,43 +1775,23 @@ static int invoke_bpf_prog(const struct btf_func_model *m, u8 **pprog,
 	if (save_ret)
 		emit_stx(&prog, BPF_DW, BPF_REG_FP, BPF_REG_0, -8);
 
-	if (p->aux->sleepable) {
-		if (emit_call(&prog, __bpf_prog_exit_sleepable, prog))
-			return -EINVAL;
-	} else {
-		/* arg1: mov rdi, progs[i] */
-		emit_mov_imm64(&prog, BPF_REG_1, (long) p >> 32,
-			       (u32) (long) p);
-		/* arg2: mov rsi, rbx <- start time in nsec */
-		emit_mov_reg(&prog, true, BPF_REG_2, BPF_REG_6);
-		if (emit_call(&prog, __bpf_prog_exit, prog))
+	/* replace 2 nops with JE insn, since jmp target is known */
+	jmp_insn[0] = X86_JE;
+	jmp_insn[1] = prog - jmp_insn - 2;
+
+	/* arg1: mov rdi, progs[i] */
+	emit_mov_imm64(&prog, BPF_REG_1, (long) p >> 32, (u32) (long) p);
+	/* arg2: mov rsi, rbx <- start time in nsec */
+	emit_mov_reg(&prog, true, BPF_REG_2, BPF_REG_6);
+	if (emit_call(&prog,
+		      p->aux->sleepable ? __bpf_prog_exit_sleepable :
+		      __bpf_prog_exit, prog))
 			return -EINVAL;
-	}
 
 	*pprog = prog;
 	return 0;
 }
 
-static void emit_nops(u8 **pprog, unsigned int len)
-{
-	unsigned int i, noplen;
-	u8 *prog = *pprog;
-	int cnt = 0;
-
-	while (len > 0) {
-		noplen = len;
-
-		if (noplen > ASM_NOP_MAX)
-			noplen = ASM_NOP_MAX;
-
-		for (i = 0; i < noplen; i++)
-			EMIT1(ideal_nops[noplen][i]);
-		len -= noplen;
-	}
-
-	*pprog = prog;
-}
-
 static void emit_align(u8 **pprog, u32 align)
 {
 	u8 *target, *prog = *pprog;
@@ -2030,6 +2208,9 @@ struct x64_jit_data {
 	struct jit_context ctx;
 };
 
+#define MAX_PASSES 20
+#define PADDING_PASSES (MAX_PASSES - 5)
+
 struct bpf_prog *bpf_int_jit_compile(struct bpf_prog *prog)
 {
 	struct bpf_binary_header *header = NULL;
@@ -2039,6 +2220,7 @@ struct bpf_prog *bpf_int_jit_compile(struct bpf_prog *prog)
 	struct jit_context ctx = {};
 	bool tmp_blinded = false;
 	bool extra_pass = false;
+	bool padding = false;
 	u8 *image = NULL;
 	int *addrs;
 	int pass;
@@ -2075,6 +2257,7 @@ struct bpf_prog *bpf_int_jit_compile(struct bpf_prog *prog)
 		image = jit_data->image;
 		header = jit_data->header;
 		extra_pass = true;
+		padding = true;
 		goto skip_init_addrs;
 	}
 	addrs = kvmalloc_array(prog->len + 1, sizeof(*addrs), GFP_KERNEL);
@@ -2100,8 +2283,10 @@ struct bpf_prog *bpf_int_jit_compile(struct bpf_prog *prog)
 	 * may converge on the last pass. In such case do one more
 	 * pass to emit the final image.
 	 */
-	for (pass = 0; pass < 20 || image; pass++) {
-		proglen = do_jit(prog, addrs, image, oldproglen, &ctx);
+	for (pass = 0; pass < MAX_PASSES || image; pass++) {
+		if (!padding && pass >= PADDING_PASSES)
+			padding = true;
+		proglen = do_jit(prog, addrs, image, oldproglen, &ctx, padding);
 		if (proglen <= 0) {
 out_image:
 			image = NULL;
@@ -2177,3 +2362,8 @@ struct bpf_prog *bpf_int_jit_compile(struct bpf_prog *prog)
 					   tmp : orig_prog);
 	return prog;
 }
+
+bool bpf_jit_supports_kfunc_call(void)
+{
+	return true;
+}

arch/x86/net/bpf_jit_comp32.c

@@ -1390,6 +1390,19 @@ static inline void emit_push_r64(const u8 src[], u8 **pprog)
 	*pprog = prog;
 }
 
+static void emit_push_r32(const u8 src[], u8 **pprog)
+{
+	u8 *prog = *pprog;
+	int cnt = 0;
+
+	/* mov ecx,dword ptr [ebp+off] */
+	EMIT3(0x8B, add_2reg(0x40, IA32_EBP, IA32_ECX), STACK_VAR(src_lo));
+	/* push ecx */
+	EMIT1(0x51);
+
+	*pprog = prog;
+}
+
 static u8 get_cond_jmp_opcode(const u8 op, bool is_cmp_lo)
 {
 	u8 jmp_cond;
@@ -1459,6 +1472,174 @@ static u8 get_cond_jmp_opcode(const u8 op, bool is_cmp_lo)
 	return jmp_cond;
 }
 
+/* i386 kernel compiles with "-mregparm=3".  From gcc document:
+ *
+ * ==== snippet ====
+ * regparm (number)
+ *	On x86-32 targets, the regparm attribute causes the compiler
+ *	to pass arguments number one to (number) if they are of integral
+ *	type in registers EAX, EDX, and ECX instead of on the stack.
+ *	Functions that take a variable number of arguments continue
+ *	to be passed all of their arguments on the stack.
+ * ==== snippet ====
+ *
+ * The first three args of a function will be considered for
+ * putting into the 32bit register EAX, EDX, and ECX.
+ *
+ * Two 32bit registers are used to pass a 64bit arg.
+ *
+ * For example,
+ * void foo(u32 a, u32 b, u32 c, u32 d):
+ *	u32 a: EAX
+ *	u32 b: EDX
+ *	u32 c: ECX
+ *	u32 d: stack
+ *
+ * void foo(u64 a, u32 b, u32 c):
+ *	u64 a: EAX (lo32) EDX (hi32)
+ *	u32 b: ECX
+ *	u32 c: stack
+ *
+ * void foo(u32 a, u64 b, u32 c):
+ *	u32 a: EAX
+ *	u64 b: EDX (lo32) ECX (hi32)
+ *	u32 c: stack
+ *
+ * void foo(u32 a, u32 b, u64 c):
+ *	u32 a: EAX
+ *	u32 b: EDX
+ *	u64 c: stack
+ *
+ * The return value will be stored in the EAX (and EDX for 64bit value).
+ *
+ * For example,
+ * u32 foo(u32 a, u32 b, u32 c):
+ *	return value: EAX
+ *
+ * u64 foo(u32 a, u32 b, u32 c):
+ *	return value: EAX (lo32) EDX (hi32)
+ *
+ * Notes:
+ *	The verifier only accepts function having integer and pointers
+ *	as its args and return value, so it does not have
+ *	struct-by-value.
+ *
+ * emit_kfunc_call() finds out the btf_func_model by calling
+ * bpf_jit_find_kfunc_model().  A btf_func_model
+ * has the details about the number of args, size of each arg,
+ * and the size of the return value.
+ *
+ * It first decides how many args can be passed by EAX, EDX, and ECX.
+ * That will decide what args should be pushed to the stack:
+ * [first_stack_regno, last_stack_regno] are the bpf regnos
+ * that should be pushed to the stack.
+ *
+ * It will first push all args to the stack because the push
+ * will need to use ECX.  Then, it moves
+ * [BPF_REG_1, first_stack_regno) to EAX, EDX, and ECX.
+ *
+ * When emitting a call (0xE8), it needs to figure out
+ * the jmp_offset relative to the jit-insn address immediately
+ * following the call (0xE8) instruction.  At this point, it knows
+ * the end of the jit-insn address after completely translated the
+ * current (BPF_JMP | BPF_CALL) bpf-insn.  It is passed as "end_addr"
+ * to the emit_kfunc_call().  Thus, it can learn the "immediate-follow-call"
+ * address by figuring out how many jit-insn is generated between
+ * the call (0xE8) and the end_addr:
+ *	- 0-1 jit-insn (3 bytes each) to restore the esp pointer if there
+ *	  is arg pushed to the stack.
+ *	- 0-2 jit-insns (3 bytes each) to handle the return value.
+ */
+static int emit_kfunc_call(const struct bpf_prog *bpf_prog, u8 *end_addr,
+			   const struct bpf_insn *insn, u8 **pprog)
+{
+	const u8 arg_regs[] = { IA32_EAX, IA32_EDX, IA32_ECX };
+	int i, cnt = 0, first_stack_regno, last_stack_regno;
+	int free_arg_regs = ARRAY_SIZE(arg_regs);
+	const struct btf_func_model *fm;
+	int bytes_in_stack = 0;
+	const u8 *cur_arg_reg;
+	u8 *prog = *pprog;
+	s64 jmp_offset;
+
+	fm = bpf_jit_find_kfunc_model(bpf_prog, insn);
+	if (!fm)
+		return -EINVAL;
+
+	first_stack_regno = BPF_REG_1;
+	for (i = 0; i < fm->nr_args; i++) {
+		int regs_needed = fm->arg_size[i] > sizeof(u32) ? 2 : 1;
+
+		if (regs_needed > free_arg_regs)
+			break;
+
+		free_arg_regs -= regs_needed;
+		first_stack_regno++;
+	}
+
+	/* Push the args to the stack */
+	last_stack_regno = BPF_REG_0 + fm->nr_args;
+	for (i = last_stack_regno; i >= first_stack_regno; i--) {
+		if (fm->arg_size[i - 1] > sizeof(u32)) {
+			emit_push_r64(bpf2ia32[i], &prog);
+			bytes_in_stack += 8;
+		} else {
+			emit_push_r32(bpf2ia32[i], &prog);
+			bytes_in_stack += 4;
+		}
+	}
+
+	cur_arg_reg = &arg_regs[0];
+	for (i = BPF_REG_1; i < first_stack_regno; i++) {
+		/* mov e[adc]x,dword ptr [ebp+off] */
+		EMIT3(0x8B, add_2reg(0x40, IA32_EBP, *cur_arg_reg++),
+		      STACK_VAR(bpf2ia32[i][0]));
+		if (fm->arg_size[i - 1] > sizeof(u32))
+			/* mov e[adc]x,dword ptr [ebp+off] */
+			EMIT3(0x8B, add_2reg(0x40, IA32_EBP, *cur_arg_reg++),
+			      STACK_VAR(bpf2ia32[i][1]));
+	}
+
+	if (bytes_in_stack)
+		/* add esp,"bytes_in_stack" */
+		end_addr -= 3;
+
+	/* mov dword ptr [ebp+off],edx */
+	if (fm->ret_size > sizeof(u32))
+		end_addr -= 3;
+
+	/* mov dword ptr [ebp+off],eax */
+	if (fm->ret_size)
+		end_addr -= 3;
+
+	jmp_offset = (u8 *)__bpf_call_base + insn->imm - end_addr;
+	if (!is_simm32(jmp_offset)) {
+		pr_err("unsupported BPF kernel function jmp_offset:%lld\n",
+		       jmp_offset);
+		return -EINVAL;
+	}
+
+	EMIT1_off32(0xE8, jmp_offset);
+
+	if (fm->ret_size)
+		/* mov dword ptr [ebp+off],eax */
+		EMIT3(0x89, add_2reg(0x40, IA32_EBP, IA32_EAX),
+		      STACK_VAR(bpf2ia32[BPF_REG_0][0]));
+
+	if (fm->ret_size > sizeof(u32))
+		/* mov dword ptr [ebp+off],edx */
+		EMIT3(0x89, add_2reg(0x40, IA32_EBP, IA32_EDX),
+		      STACK_VAR(bpf2ia32[BPF_REG_0][1]));
+
+	if (bytes_in_stack)
+		/* add esp,"bytes_in_stack" */
+		EMIT3(0x83, add_1reg(0xC0, IA32_ESP), bytes_in_stack);
+
+	*pprog = prog;
+
+	return 0;
+}
+
 static int do_jit(struct bpf_prog *bpf_prog, int *addrs, u8 *image,
 		  int oldproglen, struct jit_context *ctx)
 {
@@ -1894,6 +2075,18 @@ static int do_jit(struct bpf_prog *bpf_prog, int *addrs, u8 *image,
 			if (insn->src_reg == BPF_PSEUDO_CALL)
 				goto notyet;
 
+			if (insn->src_reg == BPF_PSEUDO_KFUNC_CALL) {
+				int err;
+
+				err = emit_kfunc_call(bpf_prog,
+						      image + addrs[i],
+						      insn, &prog);
+
+				if (err)
+					return err;
+				break;
+			}
+
 			func = (u8 *) __bpf_call_base + imm32;
 			jmp_offset = func - (image + addrs[i]);
 
@@ -2249,10 +2442,8 @@ emit_cond_jmp:		jmp_cond = get_cond_jmp_opcode(BPF_OP(code), false);
 				return -EFAULT;
 			}
 			break;
-		/* STX XADD: lock *(u32 *)(dst + off) += src */
-		case BPF_STX | BPF_XADD | BPF_W:
-		/* STX XADD: lock *(u64 *)(dst + off) += src */
-		case BPF_STX | BPF_XADD | BPF_DW:
+		case BPF_STX | BPF_ATOMIC | BPF_W:
+		case BPF_STX | BPF_ATOMIC | BPF_DW:
 			goto notyet;
 		case BPF_JMP | BPF_EXIT:
 			if (seen_exit) {
@@ -2410,3 +2601,8 @@ struct bpf_prog *bpf_int_jit_compile(struct bpf_prog *prog)
 					   tmp : orig_prog);
 	return prog;
 }
+
+bool bpf_jit_supports_kfunc_call(void)
+{
+	return true;
+}

drivers/net/ethernet/netronome/nfp/bpf/fw.h

@@ -13,8 +13,8 @@
  */
 #define NFP_BPF_SCALAR_VALUE		1
 #define NFP_BPF_MAP_VALUE		4
-#define NFP_BPF_STACK			5
-#define NFP_BPF_PACKET_DATA		7
+#define NFP_BPF_STACK			6
+#define NFP_BPF_PACKET_DATA		8
 
 enum bpf_cap_tlv_type {
 	NFP_BPF_CAP_TYPE_FUNC		= 1,

drivers/net/ethernet/netronome/nfp/bpf/jit.c

@@ -3109,13 +3109,19 @@ mem_xadd(struct nfp_prog *nfp_prog, struct nfp_insn_meta *meta, bool is64)
 	return 0;
 }
 
-static int mem_xadd4(struct nfp_prog *nfp_prog, struct nfp_insn_meta *meta)
+static int mem_atomic4(struct nfp_prog *nfp_prog, struct nfp_insn_meta *meta)
 {
+	if (meta->insn.imm != BPF_ADD)
+		return -EOPNOTSUPP;
+
 	return mem_xadd(nfp_prog, meta, false);
 }
 
-static int mem_xadd8(struct nfp_prog *nfp_prog, struct nfp_insn_meta *meta)
+static int mem_atomic8(struct nfp_prog *nfp_prog, struct nfp_insn_meta *meta)
 {
+	if (meta->insn.imm != BPF_ADD)
+		return -EOPNOTSUPP;
+
 	return mem_xadd(nfp_prog, meta, true);
 }
 
@@ -3475,8 +3481,8 @@ static const instr_cb_t instr_cb[256] = {
 	[BPF_STX | BPF_MEM | BPF_H] =	mem_stx2,
 	[BPF_STX | BPF_MEM | BPF_W] =	mem_stx4,
 	[BPF_STX | BPF_MEM | BPF_DW] =	mem_stx8,
-	[BPF_STX | BPF_XADD | BPF_W] =	mem_xadd4,
-	[BPF_STX | BPF_XADD | BPF_DW] =	mem_xadd8,
+	[BPF_STX | BPF_ATOMIC | BPF_W] =	mem_atomic4,
+	[BPF_STX | BPF_ATOMIC | BPF_DW] =	mem_atomic8,
 	[BPF_ST | BPF_MEM | BPF_B] =	mem_st1,
 	[BPF_ST | BPF_MEM | BPF_H] =	mem_st2,
 	[BPF_ST | BPF_MEM | BPF_W] =	mem_st4,

drivers/net/ethernet/netronome/nfp/bpf/main.h

@@ -428,9 +428,9 @@ static inline bool is_mbpf_classic_store_pkt(const struct nfp_insn_meta *meta)
 	return is_mbpf_classic_store(meta) && meta->ptr.type == PTR_TO_PACKET;
 }
 
-static inline bool is_mbpf_xadd(const struct nfp_insn_meta *meta)
+static inline bool is_mbpf_atomic(const struct nfp_insn_meta *meta)
 {
-	return (meta->insn.code & ~BPF_SIZE_MASK) == (BPF_STX | BPF_XADD);
+	return (meta->insn.code & ~BPF_SIZE_MASK) == (BPF_STX | BPF_ATOMIC);
 }
 
 static inline bool is_mbpf_mul(const struct nfp_insn_meta *meta)

drivers/net/ethernet/netronome/nfp/bpf/verifier.c

@@ -479,7 +479,7 @@ nfp_bpf_check_ptr(struct nfp_prog *nfp_prog, struct nfp_insn_meta *meta,
 			pr_vlog(env, "map writes not supported\n");
 			return -EOPNOTSUPP;
 		}
-		if (is_mbpf_xadd(meta)) {
+		if (is_mbpf_atomic(meta)) {
 			err = nfp_bpf_map_mark_used(env, meta, reg,
 						    NFP_MAP_USE_ATOMIC_CNT);
 			if (err)
@@ -523,12 +523,17 @@ nfp_bpf_check_store(struct nfp_prog *nfp_prog, struct nfp_insn_meta *meta,
 }
 
 static int
-nfp_bpf_check_xadd(struct nfp_prog *nfp_prog, struct nfp_insn_meta *meta,
-		   struct bpf_verifier_env *env)
+nfp_bpf_check_atomic(struct nfp_prog *nfp_prog, struct nfp_insn_meta *meta,
+		     struct bpf_verifier_env *env)
 {
 	const struct bpf_reg_state *sreg = cur_regs(env) + meta->insn.src_reg;
 	const struct bpf_reg_state *dreg = cur_regs(env) + meta->insn.dst_reg;
 
+	if (meta->insn.imm != BPF_ADD) {
+		pr_vlog(env, "atomic op not implemented: %d\n", meta->insn.imm);
+		return -EOPNOTSUPP;
+	}
+
 	if (dreg->type != PTR_TO_MAP_VALUE) {
 		pr_vlog(env, "atomic add not to a map value pointer: %d\n",
 			dreg->type);
@@ -655,8 +660,8 @@ int nfp_verify_insn(struct bpf_verifier_env *env, int insn_idx,
 	if (is_mbpf_store(meta))
 		return nfp_bpf_check_store(nfp_prog, meta, env);
 
-	if (is_mbpf_xadd(meta))
-		return nfp_bpf_check_xadd(nfp_prog, meta, env);
+	if (is_mbpf_atomic(meta))
+		return nfp_bpf_check_atomic(nfp_prog, meta, env);
 
 	if (is_mbpf_alu(meta))
 		return nfp_bpf_check_alu(nfp_prog, meta, env);

include/linux/bpf.h

@@ -14,13 +14,13 @@
 #include <linux/numa.h>
 #include <linux/mm_types.h>
 #include <linux/wait.h>
-#include <linux/u64_stats_sync.h>
 #include <linux/refcount.h>
 #include <linux/mutex.h>
 #include <linux/module.h>
 #include <linux/kallsyms.h>
 #include <linux/capability.h>
 #include <linux/percpu-refcount.h>
+#include <linux/bpfptr.h>
 
 struct bpf_verifier_env;
 struct bpf_verifier_log;
@@ -37,9 +37,12 @@ struct seq_operations;
 struct bpf_iter_aux_info;
 struct bpf_local_storage;
 struct bpf_local_storage_map;
+struct kobject;
+struct bpf_func_state;
 
 extern struct idr btf_idr;
 extern spinlock_t btf_idr_lock;
+extern struct kobject *btf_kobj;
 
 typedef int (*bpf_iter_init_seq_priv_t)(void *private_data,
 					struct bpf_iter_aux_info *aux);
@@ -126,6 +129,13 @@ struct bpf_map_ops {
 	bool (*map_meta_equal)(const struct bpf_map *meta0,
 			       const struct bpf_map *meta1);
 
+
+	int (*map_set_for_each_callback_args)(struct bpf_verifier_env *env,
+					      struct bpf_func_state *caller,
+					      struct bpf_func_state *callee);
+	int (*map_for_each_callback)(struct bpf_map *map, void *callback_fn,
+				     void *callback_ctx, u64 flags);
+
 	/* BTF name and id of struct allocated by map_alloc */
 	const char * const map_btf_name;
 	int *map_btf_id;
@@ -323,6 +333,9 @@ enum bpf_arg_type {
 	ARG_CONST_ALLOC_SIZE_OR_ZERO,	/* number of allocated bytes requested */
 	ARG_PTR_TO_BTF_ID_SOCK_COMMON,	/* pointer to in-kernel sock_common or bpf-mirrored bpf_sock */
 	ARG_PTR_TO_PERCPU_BTF_ID,	/* pointer to in-kernel percpu type */
+	ARG_PTR_TO_FUNC,	/* pointer to a bpf program function */
+	ARG_PTR_TO_STACK_OR_NULL,	/* pointer to stack or NULL */
+	ARG_PTR_TO_CONST_STR,	/* pointer to a null terminated read-only string */
 	__BPF_ARG_TYPE_MAX,
 
 	/* Extended arg_types. */
@@ -427,6 +440,7 @@ enum bpf_reg_type {
 	PTR_TO_CTX,		 /* reg points to bpf_context */
 	CONST_PTR_TO_MAP,	 /* reg points to struct bpf_map */
 	PTR_TO_MAP_VALUE,	 /* reg points to map element value */
+	PTR_TO_MAP_KEY,		 /* reg points to a map element key */
 	PTR_TO_STACK,		 /* reg == frame_pointer + offset */
 	PTR_TO_PACKET_META,	 /* skb->data - meta_len */
 	PTR_TO_PACKET,		 /* reg points to skb->data */
@@ -454,6 +468,7 @@ enum bpf_reg_type {
 	 */
 	PTR_TO_MEM,		 /* reg points to valid memory region */
 	PTR_TO_BUF,		 /* reg points to a read/write buffer */
+	PTR_TO_FUNC,		 /* reg points to a bpf program function */
 	PTR_TO_PERCPU_BTF_ID,	 /* reg points to a percpu kernel variable */
 	__BPF_REG_TYPE_MAX,
 
@@ -478,7 +493,10 @@ struct bpf_insn_access_aux {
 	enum bpf_reg_type reg_type;
 	union {
 		int ctx_field_size;
-		u32 btf_id;
+		struct {
+			struct btf *btf;
+			u32 btf_id;
+		};
 	};
 	struct bpf_verifier_log *log; /* for verbose logs */
 };
@@ -515,9 +533,11 @@ struct bpf_verifier_ops {
 				  struct bpf_insn *dst,
 				  struct bpf_prog *prog, u32 *target_size);
 	int (*btf_struct_access)(struct bpf_verifier_log *log,
+				 const struct btf *btf,
 				 const struct btf_type *t, int off, int size,
 				 enum bpf_access_type atype,
 				 u32 *next_btf_id);
+	bool (*check_kfunc_call)(u32 kfunc_btf_id, struct module *owner);
 };
 
 struct bpf_prog_offload_ops {
@@ -568,11 +588,10 @@ enum bpf_cgroup_storage_type {
  */
 #define MAX_BPF_FUNC_ARGS 12
 
-struct bpf_prog_stats {
-	u64 cnt;
-	u64 nsecs;
-	struct u64_stats_sync syncp;
-} __aligned(2 * sizeof(u64));
+/* The maximum number of arguments passed through registers
+ * a single function may have.
+ */
+#define MAX_BPF_FUNC_REG_ARGS 5
 
 struct btf_func_model {
 	u8 ret_size;
@@ -599,7 +618,7 @@ struct btf_func_model {
 /* Each call __bpf_prog_enter + call bpf_func + call __bpf_prog_exit is ~50
  * bytes on x86.  Pick a number to fit into BPF_IMAGE_SIZE / 2
  */
-#define BPF_MAX_TRAMP_PROGS 40
+#define BPF_MAX_TRAMP_PROGS 38
 
 struct bpf_tramp_progs {
 	struct bpf_prog *progs[BPF_MAX_TRAMP_PROGS];
@@ -632,10 +651,10 @@ int arch_prepare_bpf_trampoline(struct bpf_tramp_image *tr, void *image, void *i
 				struct bpf_tramp_progs *tprogs,
 				void *orig_call);
 /* these two functions are called from generated trampoline */
-u64 notrace __bpf_prog_enter(void);
+u64 notrace __bpf_prog_enter(struct bpf_prog *prog);
 void notrace __bpf_prog_exit(struct bpf_prog *prog, u64 start);
-void notrace __bpf_prog_enter_sleepable(void);
-void notrace __bpf_prog_exit_sleepable(void);
+u64 notrace __bpf_prog_enter_sleepable(struct bpf_prog *prog);
+void notrace __bpf_prog_exit_sleepable(struct bpf_prog *prog, u64 start);
 void notrace __bpf_tramp_enter(struct bpf_tramp_image *tr);
 void notrace __bpf_tramp_exit(struct bpf_tramp_image *tr);
 
@@ -842,9 +861,17 @@ struct bpf_ctx_arg_aux {
 	u32 btf_id;
 };
 
+struct btf_mod_pair {
+	struct btf *btf;
+	struct module *module;
+};
+
+struct bpf_kfunc_desc_tab;
+
 struct bpf_prog_aux {
 	atomic64_t refcnt;
 	u32 used_map_cnt;
+	u32 used_btf_cnt;
 	u32 max_ctx_offset;
 	u32 max_pkt_offset;
 	u32 max_tp_access;
@@ -856,6 +883,7 @@ struct bpf_prog_aux {
 	u32 ctx_arg_info_size;
 	u32 max_rdonly_access;
 	u32 max_rdwr_access;
+	struct btf *attach_btf;
 	const struct bpf_ctx_arg_aux *ctx_arg_info;
 	struct mutex dst_mutex; /* protects dst_* pointers below, *after* prog becomes visible */
 	struct bpf_prog *dst_prog;
@@ -876,14 +904,18 @@ struct bpf_prog_aux {
 	struct bpf_prog **func;
 	void *jit_data; /* JIT specific data. arch dependent */
 	struct bpf_jit_poke_descriptor *poke_tab;
+	struct bpf_kfunc_desc_tab *kfunc_tab;
+	struct bpf_kfunc_btf_tab *kfunc_btf_tab;
 	u32 size_poke_tab;
 	struct bpf_ksym ksym;
 	const struct bpf_prog_ops *ops;
 	struct bpf_map **used_maps;
 	struct mutex used_maps_mutex; /* mutex for used_maps and used_map_cnt */
+	struct btf_mod_pair *used_btfs;
 	struct bpf_prog *prog;
 	struct user_struct *user;
 	u64 load_time; /* ns since boottime */
+	u32 verified_insns;
 	struct bpf_map *cgroup_storage[MAX_BPF_CGROUP_STORAGE_TYPE];
 	char name[BPF_OBJ_NAME_LEN];
 #ifdef CONFIG_SECURITY
@@ -917,7 +949,6 @@ struct bpf_prog_aux {
 	u32 linfo_idx;
 	u32 num_exentries;
 	struct exception_table_entry *extable;
-	struct bpf_prog_stats __percpu *stats;
 	union {
 		struct work_struct work;
 		struct rcu_head	rcu;
@@ -1092,7 +1123,6 @@ struct bpf_event_entry {
 
 bool bpf_prog_array_compatible(struct bpf_array *array, const struct bpf_prog *fp);
 int bpf_prog_calc_tag(struct bpf_prog *fp);
-const char *kernel_type_name(u32 btf_type_id);
 
 const struct bpf_func_proto *bpf_get_trace_printk_proto(void);
 
@@ -1445,7 +1475,7 @@ struct bpf_iter__bpf_map_elem {
 int bpf_iter_reg_target(const struct bpf_iter_reg *reg_info);
 void bpf_iter_unreg_target(const struct bpf_iter_reg *reg_info);
 bool bpf_iter_prog_supported(struct bpf_prog *prog);
-int bpf_iter_link_attach(const union bpf_attr *attr, struct bpf_prog *prog);
+int bpf_iter_link_attach(const union bpf_attr *attr, bpfptr_t uattr, struct bpf_prog *prog);
 int bpf_iter_new_fd(struct bpf_link *link);
 bool bpf_link_is_iter(struct bpf_link *link);
 struct bpf_prog *bpf_iter_get_info(struct bpf_iter_meta *meta, bool in_stop);
@@ -1472,7 +1502,7 @@ int bpf_fd_htab_map_update_elem(struct bpf_map *map, struct file *map_file,
 int bpf_fd_htab_map_lookup_elem(struct bpf_map *map, void *key, u32 *value);
 
 int bpf_get_file_flag(int flags);
-int bpf_check_uarg_tail_zero(void __user *uaddr, size_t expected_size,
+int bpf_check_uarg_tail_zero(bpfptr_t uaddr, size_t expected_size,
 			     size_t actual_size);
 
 /* memcpy that is used with 8-byte aligned pointers, power-of-8 size and
@@ -1492,8 +1522,7 @@ static inline void bpf_long_memcpy(void *dst, const void *src, u32 size)
 }
 
 /* verify correctness of eBPF program */
-int bpf_check(struct bpf_prog **fp, union bpf_attr *attr,
-	      union bpf_attr __user *uattr);
+int bpf_check(struct bpf_prog **fp, union bpf_attr *attr, bpfptr_t uattr);
 
 #ifndef CONFIG_BPF_JIT_ALWAYS_ON
 void bpf_patch_call_args(struct bpf_insn *insn, u32 stack_depth);
@@ -1545,15 +1574,20 @@ int bpf_prog_test_run_flow_dissector(struct bpf_prog *prog,
 int bpf_prog_test_run_raw_tp(struct bpf_prog *prog,
 			     const union bpf_attr *kattr,
 			     union bpf_attr __user *uattr);
+int bpf_prog_test_run_sk_lookup(struct bpf_prog *prog,
+				const union bpf_attr *kattr,
+				union bpf_attr __user *uattr);
+bool bpf_prog_test_check_kfunc_call(u32 kfunc_id, struct module *owner);
 bool btf_ctx_access(int off, int size, enum bpf_access_type type,
 		    const struct bpf_prog *prog,
 		    struct bpf_insn_access_aux *info);
-int btf_struct_access(struct bpf_verifier_log *log,
+int btf_struct_access(struct bpf_verifier_log *log, const struct btf *btf,
 		      const struct btf_type *t, int off, int size,
 		      enum bpf_access_type atype,
 		      u32 *next_btf_id);
 bool btf_struct_ids_match(struct bpf_verifier_log *log,
-			  int off, u32 id, u32 need_type_id);
+			  const struct btf *btf, u32 id, int off,
+			  const struct btf *need_btf, u32 need_type_id);
 
 int btf_distill_func_proto(struct bpf_verifier_log *log,
 			   struct btf *btf,
@@ -1562,8 +1596,11 @@ int btf_distill_func_proto(struct bpf_verifier_log *log,
 			   struct btf_func_model *m);
 
 struct bpf_reg_state;
-int btf_check_func_arg_match(struct bpf_verifier_env *env, int subprog,
-			     struct bpf_reg_state *regs);
+int btf_check_subprog_arg_match(struct bpf_verifier_env *env, int subprog,
+				struct bpf_reg_state *regs);
+int btf_check_kfunc_arg_match(struct bpf_verifier_env *env,
+			      const struct btf *btf, u32 func_id,
+			      struct bpf_reg_state *regs);
 int btf_prepare_func_args(struct bpf_verifier_env *env, int subprog,
 			  struct bpf_reg_state *reg);
 int btf_check_type_match(struct bpf_verifier_log *log, const struct bpf_prog *prog,
@@ -1573,6 +1610,18 @@ struct bpf_prog *bpf_prog_by_id(u32 id);
 struct bpf_link *bpf_link_by_id(u32 id);
 
 const struct bpf_func_proto *bpf_base_func_proto(enum bpf_func_id func_id);
+bool bpf_prog_has_kfunc_call(const struct bpf_prog *prog);
+const struct btf_func_model *
+bpf_jit_find_kfunc_model(const struct bpf_prog *prog,
+			 const struct bpf_insn *insn);
+
+struct bpf_core_ctx {
+	struct bpf_verifier_log *log;
+	const struct btf *btf;
+};
+
+int bpf_core_apply(struct bpf_core_ctx *ctx, const struct bpf_core_relo *relo,
+		   int relo_idx, void *insn);
 
 static inline bool unprivileged_ebpf_enabled(void)
 {
@@ -1759,6 +1808,19 @@ static inline int bpf_prog_test_run_flow_dissector(struct bpf_prog *prog,
 	return -ENOTSUPP;
 }
 
+static inline int bpf_prog_test_run_sk_lookup(struct bpf_prog *prog,
+					      const union bpf_attr *kattr,
+					      union bpf_attr __user *uattr)
+{
+	return -ENOTSUPP;
+}
+
+static inline bool bpf_prog_test_check_kfunc_call(u32 kfunc_id,
+						  struct module *owner)
+{
+	return false;
+}
+
 static inline void bpf_map_put(struct bpf_map *map)
 {
 }
@@ -1774,6 +1836,18 @@ bpf_base_func_proto(enum bpf_func_id func_id)
 	return NULL;
 }
 
+static inline bool bpf_prog_has_kfunc_call(const struct bpf_prog *prog)
+{
+	return false;
+}
+
+static inline const struct btf_func_model *
+bpf_jit_find_kfunc_model(const struct bpf_prog *prog,
+			 const struct bpf_insn *insn)
+{
+	return NULL;
+}
+
 static inline bool unprivileged_ebpf_enabled(void)
 {
 	return false;
@@ -1781,6 +1855,9 @@ static inline bool unprivileged_ebpf_enabled(void)
 
 #endif /* CONFIG_BPF_SYSCALL */
 
+void __bpf_free_used_btfs(struct bpf_prog_aux *aux,
+			  struct btf_mod_pair *used_btfs, u32 len);
+
 static inline struct bpf_prog *bpf_prog_get_type(u32 ufd,
 						 enum bpf_prog_type type)
 {
@@ -1833,6 +1910,9 @@ static inline bool bpf_map_is_dev_bound(struct bpf_map *map)
 
 struct bpf_map *bpf_map_offload_map_alloc(union bpf_attr *attr);
 void bpf_map_offload_map_free(struct bpf_map *map);
+int bpf_prog_test_run_syscall(struct bpf_prog *prog,
+			      const union bpf_attr *kattr,
+			      union bpf_attr __user *uattr);
 #else
 static inline int bpf_prog_offload_init(struct bpf_prog *prog,
 					union bpf_attr *attr)
@@ -1858,6 +1938,13 @@ static inline struct bpf_map *bpf_map_offload_map_alloc(union bpf_attr *attr)
 static inline void bpf_map_offload_map_free(struct bpf_map *map)
 {
 }
+
+static inline int bpf_prog_test_run_syscall(struct bpf_prog *prog,
+					    const union bpf_attr *kattr,
+					    union bpf_attr __user *uattr)
+{
+	return -ENOTSUPP;
+}
 #endif /* CONFIG_NET && CONFIG_BPF_SYSCALL */
 
 #if defined(CONFIG_BPF_STREAM_PARSER)
@@ -1973,8 +2060,12 @@ extern const struct bpf_func_proto bpf_skc_to_tcp_request_sock_proto;
 extern const struct bpf_func_proto bpf_skc_to_udp6_sock_proto;
 extern const struct bpf_func_proto bpf_copy_from_user_proto;
 extern const struct bpf_func_proto bpf_snprintf_btf_proto;
+extern const struct bpf_func_proto bpf_snprintf_proto;
 extern const struct bpf_func_proto bpf_per_cpu_ptr_proto;
 extern const struct bpf_func_proto bpf_this_cpu_ptr_proto;
+extern const struct bpf_func_proto bpf_for_each_map_elem_proto;
+extern const struct bpf_func_proto bpf_btf_find_by_name_kind_proto;
+extern const struct bpf_func_proto bpf_kallsyms_lookup_name_proto;
 
 const struct bpf_func_proto *bpf_tracing_func_proto(
 	enum bpf_func_id func_id, const struct bpf_prog *prog);
@@ -2092,4 +2183,24 @@ int bpf_arch_text_poke(void *ip, enum bpf_text_poke_type t,
 struct btf_id_set;
 bool btf_id_set_contains(const struct btf_id_set *set, u32 id);
 
+enum bpf_printf_mod_type {
+	BPF_PRINTF_INT,
+	BPF_PRINTF_LONG,
+	BPF_PRINTF_LONG_LONG,
+};
+
+/* Workaround for getting va_list handling working with different argument type
+ * combinations generically for 32 and 64 bit archs.
+ */
+#define BPF_CAST_FMT_ARG(arg_nb, args, mod)				\
+	(mod[arg_nb] == BPF_PRINTF_LONG_LONG ||				\
+	 (mod[arg_nb] == BPF_PRINTF_LONG && __BITS_PER_LONG == 64)	\
+	  ? (u64)args[arg_nb]						\
+	  : (u32)args[arg_nb])
+
+int bpf_printf_prepare(char *fmt, u32 fmt_size, const u64 *raw_args,
+		       u64 *final_args, enum bpf_printf_mod_type *mod,
+		       u32 num_args);
+void bpf_printf_cleanup(void);
+
 #endif /* _LINUX_BPF_H */

include/linux/bpf_types.h

@@ -81,6 +81,8 @@ BPF_PROG_TYPE(BPF_PROG_TYPE_LSM, lsm,
 BPF_PROG_TYPE(BPF_PROG_TYPE_SCHED, bpf_sched,
 	      void *, void *)
 #endif /* CONFIG_BPF_SCHED */
+BPF_PROG_TYPE(BPF_PROG_TYPE_SYSCALL, bpf_syscall,
+	      void *, void *)
 
 BPF_MAP_TYPE(BPF_MAP_TYPE_ARRAY, array_map_ops)
 BPF_MAP_TYPE(BPF_MAP_TYPE_PERCPU_ARRAY, percpu_array_map_ops)

include/linux/bpf_verifier.h

@@ -5,6 +5,7 @@
 #define _LINUX_BPF_VERIFIER_H 1
 
 #include <linux/bpf.h> /* for enum bpf_reg_type */
+#include <linux/btf.h> /* for struct btf and btf_id() */
 #include <linux/filter.h> /* for MAX_BPF_STACK */
 #include <linux/tnum.h>
 
@@ -45,6 +46,8 @@ enum bpf_reg_liveness {
 struct bpf_reg_state {
 	/* Ordering of fields matters.  See states_equal() */
 	enum bpf_reg_type type;
+	/* Fixed part of pointer offset, pointer types only */
+	s32 off;
 	union {
 		/* valid when type == PTR_TO_PACKET */
 		u16 range;
@@ -54,15 +57,22 @@ struct bpf_reg_state {
 		 */
 		struct bpf_map *map_ptr;
 
-		u32 btf_id; /* for PTR_TO_BTF_ID */
+		/* for PTR_TO_BTF_ID */
+		struct {
+			struct btf *btf;
+			u32 btf_id;
+		};
 
 		u32 mem_size; /* for PTR_TO_MEM | PTR_TO_MEM_OR_NULL */
 
 		/* Max size from any of the above. */
-		unsigned long raw;
+		struct {
+			unsigned long raw1;
+			unsigned long raw2;
+		} raw;
+
+		u32 subprogno; /* for PTR_TO_FUNC */
 	};
-	/* Fixed part of pointer offset, pointer types only */
-	s32 off;
 	/* For PTR_TO_PACKET, used to find other pointers with the same variable
 	 * offset, so they can share range knowledge.
 	 * For PTR_TO_MAP_VALUE_OR_NULL this is used to share which map value we
@@ -198,6 +208,7 @@ struct bpf_func_state {
 	int acquired_refs;
 	struct bpf_reference_state *refs;
 	int allocated_stack;
+	bool in_callback_fn;
 	struct bpf_stack_state *stack;
 };
 
@@ -321,7 +332,10 @@ struct bpf_insn_aux_data {
 		struct {
 			enum bpf_reg_type reg_type;	/* type of pseudo_btf_id */
 			union {
-				u32 btf_id;	/* btf_id for struct typed var */
+				struct {
+					struct btf *btf;
+					u32 btf_id;	/* btf_id for struct typed var */
+				};
 				u32 mem_size;	/* mem_size for non-struct typed var */
 			};
 		} btf_var;
@@ -339,6 +353,7 @@ struct bpf_insn_aux_data {
 };
 
 #define MAX_USED_MAPS 64 /* max number of maps accessed by one eBPF program */
+#define MAX_USED_BTFS 64 /* max number of BTFs accessed by one BPF program */
 
 #define BPF_VERIFIER_TMP_LOG_SIZE	1024
 
@@ -404,7 +419,9 @@ struct bpf_verifier_env {
 	struct bpf_verifier_state_list **explored_states; /* search pruning optimization */
 	struct bpf_verifier_state_list *free_list;
 	struct bpf_map *used_maps[MAX_USED_MAPS]; /* array of map's used by eBPF program */
+	struct btf_mod_pair used_btfs[MAX_USED_BTFS]; /* array of BTF's used by BPF program */
 	u32 used_map_cnt;		/* number of used maps */
+	u32 used_btf_cnt;		/* number of used BTF objects */
 	u32 id_gen;			/* used to generate unique reg IDs */
 	bool explore_alu_limits;
 	bool allow_ptr_leaks;
@@ -443,6 +460,7 @@ struct bpf_verifier_env {
 	u32 peak_states;
 	/* longest register parentage chain walked for liveness marking */
 	u32 longest_mark_read_walk;
+	bpfptr_t fd_array;
 	/* buffer used in reg_type_str() to generate reg_type string */
 	char type_str_buf[TYPE_STR_BUF_LEN];
 };
@@ -478,12 +496,26 @@ bpf_prog_offload_remove_insns(struct bpf_verifier_env *env, u32 off, u32 cnt);
 
 int check_ptr_off_reg(struct bpf_verifier_env *env,
 		      const struct bpf_reg_state *reg, int regno);
+int check_mem_reg(struct bpf_verifier_env *env, struct bpf_reg_state *reg,
+		   u32 regno, u32 mem_size);
 
 /* this lives here instead of in bpf.h because it needs to dereference tgt_prog */
 static inline u64 bpf_trampoline_compute_key(const struct bpf_prog *tgt_prog,
-					     u32 btf_id)
+					     struct btf *btf, u32 btf_id)
+{
+	if (tgt_prog)
+		return ((u64)tgt_prog->aux->id << 32) | btf_id;
+	else
+		return ((u64)btf_obj_id(btf) << 32) | 0x80000000 | btf_id;
+}
+
+/* unpack the IDs from the key as constructed above */
+static inline void bpf_trampoline_unpack_key(u64 key, u32 *obj_id, u32 *btf_id)
 {
-        return tgt_prog ? (((u64)tgt_prog->aux->id) << 32 | btf_id) : btf_id;
+	if (obj_id)
+		*obj_id = key >> 32;
+	if (btf_id)
+		*btf_id = key & 0x7FFFFFFF;
 }
 
 int bpf_check_attach_target(struct bpf_verifier_log *log,
@@ -491,6 +523,8 @@ int bpf_check_attach_target(struct bpf_verifier_log *log,
 			    const struct bpf_prog *tgt_prog,
 			    u32 btf_id,
 			    struct bpf_attach_target_info *tgt_info);
+void bpf_free_kfunc_btf_tab(struct bpf_kfunc_btf_tab *tab);
+
 #define BPF_BASE_TYPE_MASK	GENMASK(BPF_BASE_TYPE_BITS - 1, 0)
 
 /* extract base type from bpf_{arg, return, reg}_type. */

include/linux/bpfptr.h

+/* SPDX-License-Identifier: GPL-2.0-only */
+/* A pointer that can point to either kernel or userspace memory. */
+#ifndef _LINUX_BPFPTR_H
+#define _LINUX_BPFPTR_H
+
+#include <linux/mm.h>
+#include <linux/sockptr.h>
+
+typedef sockptr_t bpfptr_t;
+
+static inline bool bpfptr_is_kernel(bpfptr_t bpfptr)
+{
+	return bpfptr.is_kernel;
+}
+
+static inline bpfptr_t KERNEL_BPFPTR(void *p)
+{
+	return (bpfptr_t) { .kernel = p, .is_kernel = true };
+}
+
+static inline bpfptr_t USER_BPFPTR(void __user *p)
+{
+	return (bpfptr_t) { .user = p };
+}
+
+static inline bpfptr_t make_bpfptr(u64 addr, bool is_kernel)
+{
+	if (is_kernel)
+		return KERNEL_BPFPTR((void*) (uintptr_t) addr);
+	else
+		return USER_BPFPTR(u64_to_user_ptr(addr));
+}
+
+static inline bool bpfptr_is_null(bpfptr_t bpfptr)
+{
+	if (bpfptr_is_kernel(bpfptr))
+		return !bpfptr.kernel;
+	return !bpfptr.user;
+}
+
+static inline void bpfptr_add(bpfptr_t *bpfptr, size_t val)
+{
+	if (bpfptr_is_kernel(*bpfptr))
+		bpfptr->kernel += val;
+	else
+		bpfptr->user += val;
+}
+
+static inline int copy_from_bpfptr_offset(void *dst, bpfptr_t src,
+					  size_t offset, size_t size)
+{
+	return copy_from_sockptr_offset(dst, (sockptr_t) src, offset, size);
+}
+
+static inline int copy_from_bpfptr(void *dst, bpfptr_t src, size_t size)
+{
+	return copy_from_bpfptr_offset(dst, src, 0, size);
+}
+
+static inline int copy_to_bpfptr_offset(bpfptr_t dst, size_t offset,
+					const void *src, size_t size)
+{
+	return copy_to_sockptr_offset((sockptr_t) dst, offset, src, size);
+}
+
+static inline void *memdup_bpfptr(bpfptr_t src, size_t len)
+{
+	return memdup_sockptr((sockptr_t) src, len);
+}
+
+static inline long strncpy_from_bpfptr(char *dst, bpfptr_t src, size_t count)
+{
+	return strncpy_from_sockptr(dst, (sockptr_t) src, count);
+}
+
+#endif /* _LINUX_BPFPTR_H */

include/linux/btf.h

@@ -5,6 +5,7 @@
 #define _LINUX_BTF_H 1
 
 #include <linux/types.h>
+#include <linux/bpfptr.h>
 #include <uapi/linux/btf.h>
 #include <uapi/linux/bpf.h>
 
@@ -18,8 +19,9 @@ struct btf_show;
 
 extern const struct file_operations btf_fops;
 
+void btf_get(struct btf *btf);
 void btf_put(struct btf *btf);
-int btf_new_fd(const union bpf_attr *attr);
+int btf_new_fd(const union bpf_attr *attr, bpfptr_t uattr);
 struct btf *btf_get_by_fd(int fd);
 int btf_get_info_by_fd(const struct btf *btf,
 		       const union bpf_attr *attr,
@@ -88,7 +90,11 @@ int btf_type_snprintf_show(const struct btf *btf, u32 type_id, void *obj,
 			   char *buf, int len, u64 flags);
 
 int btf_get_fd_by_id(u32 id);
-u32 btf_id(const struct btf *btf);
+u32 btf_obj_id(const struct btf *btf);
+bool btf_is_kernel(const struct btf *btf);
+bool btf_is_module(const struct btf *btf);
+struct module *btf_try_get_module(const struct btf *btf);
+u32 btf_nr_types(const struct btf *btf);
 bool btf_member_is_reg_int(const struct btf *btf, const struct btf_type *s,
 			   const struct btf_member *m,
 			   u32 expected_offset, u32 expected_size);
@@ -104,6 +110,7 @@ const struct btf_type *btf_type_resolve_func_ptr(const struct btf *btf,
 const struct btf_type *
 btf_resolve_size(const struct btf *btf, const struct btf_type *type,
 		 u32 *type_size);
+const char *btf_type_str(const struct btf_type *t);
 
 #define for_each_member(i, struct_type, member)			\
 	for (i = 0, member = btf_type_member(struct_type);	\
@@ -135,6 +142,58 @@ static inline bool btf_type_is_enum(const struct btf_type *t)
 	return BTF_INFO_KIND(t->info) == BTF_KIND_ENUM;
 }
 
+static inline bool str_is_empty(const char *s)
+{
+	return !s || !s[0];
+}
+
+static inline u16 btf_kind(const struct btf_type *t)
+{
+	return BTF_INFO_KIND(t->info);
+}
+
+static inline bool btf_is_enum(const struct btf_type *t)
+{
+	return btf_kind(t) == BTF_KIND_ENUM;
+}
+
+static inline bool btf_is_composite(const struct btf_type *t)
+{
+	u16 kind = btf_kind(t);
+
+	return kind == BTF_KIND_STRUCT || kind == BTF_KIND_UNION;
+}
+
+static inline bool btf_is_array(const struct btf_type *t)
+{
+	return btf_kind(t) == BTF_KIND_ARRAY;
+}
+
+static inline bool btf_is_int(const struct btf_type *t)
+{
+	return btf_kind(t) == BTF_KIND_INT;
+}
+
+static inline bool btf_is_ptr(const struct btf_type *t)
+{
+	return btf_kind(t) == BTF_KIND_PTR;
+}
+
+static inline u8 btf_int_offset(const struct btf_type *t)
+{
+	return BTF_INT_OFFSET(*(u32 *)(t + 1));
+}
+
+static inline u8 btf_int_encoding(const struct btf_type *t)
+{
+	return BTF_INT_ENCODING(*(u32 *)(t + 1));
+}
+
+static inline bool btf_type_is_scalar(const struct btf_type *t)
+{
+	return btf_type_is_int(t) || btf_type_is_enum(t);
+}
+
 static inline bool btf_type_is_typedef(const struct btf_type *t)
 {
 	return BTF_INFO_KIND(t->info) == BTF_KIND_TYPEDEF;
@@ -170,6 +229,11 @@ static inline u16 btf_type_vlen(const struct btf_type *t)
 	return BTF_INFO_VLEN(t->info);
 }
 
+static inline u16 btf_vlen(const struct btf_type *t)
+{
+	return btf_type_vlen(t);
+}
+
 static inline u16 btf_func_linkage(const struct btf_type *t)
 {
 	return BTF_INFO_VLEN(t->info);
@@ -180,25 +244,54 @@ static inline bool btf_type_kflag(const struct btf_type *t)
 	return BTF_INFO_KFLAG(t->info);
 }
 
-static inline u32 btf_member_bit_offset(const struct btf_type *struct_type,
-					const struct btf_member *member)
+static inline u32 __btf_member_bit_offset(const struct btf_type *struct_type,
+					  const struct btf_member *member)
 {
 	return btf_type_kflag(struct_type) ? BTF_MEMBER_BIT_OFFSET(member->offset)
 					   : member->offset;
 }
 
-static inline u32 btf_member_bitfield_size(const struct btf_type *struct_type,
-					   const struct btf_member *member)
+static inline u32 __btf_member_bitfield_size(const struct btf_type *struct_type,
+					     const struct btf_member *member)
 {
 	return btf_type_kflag(struct_type) ? BTF_MEMBER_BITFIELD_SIZE(member->offset)
 					   : 0;
 }
 
+static inline struct btf_member *btf_members(const struct btf_type *t)
+{
+	return (struct btf_member *)(t + 1);
+}
+
+static inline u32 btf_member_bit_offset(const struct btf_type *t, u32 member_idx)
+{
+	const struct btf_member *m = btf_members(t) + member_idx;
+
+	return __btf_member_bit_offset(t, m);
+}
+
+static inline u32 btf_member_bitfield_size(const struct btf_type *t, u32 member_idx)
+{
+	const struct btf_member *m = btf_members(t) + member_idx;
+
+	return __btf_member_bitfield_size(t, m);
+}
+
 static inline const struct btf_member *btf_type_member(const struct btf_type *t)
 {
 	return (const struct btf_member *)(t + 1);
 }
 
+static inline struct btf_array *btf_array(const struct btf_type *t)
+{
+	return (struct btf_array *)(t + 1);
+}
+
+static inline struct btf_enum *btf_enum(const struct btf_type *t)
+{
+	return (struct btf_enum *)(t + 1);
+}
+
 static inline const struct btf_var_secinfo *btf_type_var_secinfo(
 		const struct btf_type *t)
 {
@@ -206,6 +299,8 @@ static inline const struct btf_var_secinfo *btf_type_var_secinfo(
 }
 
 #ifdef CONFIG_BPF_SYSCALL
+struct bpf_prog;
+
 const struct btf_type *btf_type_by_id(const struct btf *btf, u32 type_id);
 const char *btf_name_by_offset(const struct btf *btf, u32 offset);
 struct btf *btf_parse_vmlinux(void);
@@ -223,4 +318,40 @@ static inline const char *btf_name_by_offset(const struct btf *btf,
 }
 #endif
 
+struct kfunc_btf_id_set {
+	struct list_head list;
+	struct btf_id_set *set;
+	struct module *owner;
+};
+
+struct kfunc_btf_id_list;
+
+#ifdef CONFIG_DEBUG_INFO_BTF_MODULES
+void register_kfunc_btf_id_set(struct kfunc_btf_id_list *l,
+			       struct kfunc_btf_id_set *s);
+void unregister_kfunc_btf_id_set(struct kfunc_btf_id_list *l,
+				 struct kfunc_btf_id_set *s);
+bool bpf_check_mod_kfunc_call(struct kfunc_btf_id_list *klist, u32 kfunc_id,
+			      struct module *owner);
+#else
+static inline void register_kfunc_btf_id_set(struct kfunc_btf_id_list *l,
+					     struct kfunc_btf_id_set *s)
+{
+}
+static inline void unregister_kfunc_btf_id_set(struct kfunc_btf_id_list *l,
+					       struct kfunc_btf_id_set *s)
+{
+}
+static inline bool bpf_check_mod_kfunc_call(struct kfunc_btf_id_list *klist,
+					    u32 kfunc_id, struct module *owner)
+{
+	return false;
+}
+#endif
+
+#define DEFINE_KFUNC_BTF_ID_SET(set, name)                                     \
+	struct kfunc_btf_id_set name = { LIST_HEAD_INIT(name.list), (set),     \
+					 THIS_MODULE }
+
+extern struct kfunc_btf_id_list prog_test_kfunc_list;
 #endif

include/linux/filter.h

@@ -22,6 +22,7 @@
 #include <linux/vmalloc.h>
 #include <linux/sockptr.h>
 #include <crypto/sha1.h>
+#include <linux/u64_stats_sync.h>
 
 #include <net/sch_generic.h>
 
@@ -264,15 +265,32 @@ static inline bool insn_is_zext(const struct bpf_insn *insn)
 		.off   = OFF,					\
 		.imm   = 0 })
 
-/* Atomic memory add, *(uint *)(dst_reg + off16) += src_reg */
 
-#define BPF_STX_XADD(SIZE, DST, SRC, OFF)			\
+/*
+ * Atomic operations:
+ *
+ *   BPF_ADD                  *(uint *) (dst_reg + off16) += src_reg
+ *   BPF_AND                  *(uint *) (dst_reg + off16) &= src_reg
+ *   BPF_OR                   *(uint *) (dst_reg + off16) |= src_reg
+ *   BPF_XOR                  *(uint *) (dst_reg + off16) ^= src_reg
+ *   BPF_ADD | BPF_FETCH      src_reg = atomic_fetch_add(dst_reg + off16, src_reg);
+ *   BPF_AND | BPF_FETCH      src_reg = atomic_fetch_and(dst_reg + off16, src_reg);
+ *   BPF_OR | BPF_FETCH       src_reg = atomic_fetch_or(dst_reg + off16, src_reg);
+ *   BPF_XOR | BPF_FETCH      src_reg = atomic_fetch_xor(dst_reg + off16, src_reg);
+ *   BPF_XCHG                 src_reg = atomic_xchg(dst_reg + off16, src_reg)
+ *   BPF_CMPXCHG              r0 = atomic_cmpxchg(dst_reg + off16, r0, src_reg)
+ */
+
+#define BPF_ATOMIC_OP(SIZE, OP, DST, SRC, OFF)			\
 	((struct bpf_insn) {					\
-		.code  = BPF_STX | BPF_SIZE(SIZE) | BPF_XADD,	\
+		.code  = BPF_STX | BPF_SIZE(SIZE) | BPF_ATOMIC,	\
 		.dst_reg = DST,					\
 		.src_reg = SRC,					\
 		.off   = OFF,					\
-		.imm   = 0 })
+		.imm   = OP })
+
+/* Legacy alias */
+#define BPF_STX_XADD(SIZE, DST, SRC, OFF) BPF_ATOMIC_OP(SIZE, BPF_ADD, DST, SRC, OFF)
 
 /* Memory store, *(uint *) (dst_reg + off16) = imm32 */
 
@@ -537,6 +555,13 @@ struct bpf_binary_header {
 	u8 image[] __aligned(BPF_IMAGE_ALIGNMENT);
 };
 
+struct bpf_prog_stats {
+	u64 cnt;
+	u64 nsecs;
+	u64 misses;
+	struct u64_stats_sync syncp;
+} __aligned(2 * sizeof(u64));
+
 struct bpf_prog {
 	u16			pages;		/* Number of allocated pages */
 	u16			jited:1,	/* Is our filter JIT'ed? */
@@ -555,10 +580,12 @@ struct bpf_prog {
 	u32			len;		/* Number of filter blocks */
 	u32			jited_len;	/* Size of jited insns in bytes */
 	u8			tag[BPF_TAG_SIZE];
-	struct bpf_prog_aux	*aux;		/* Auxiliary fields */
-	struct sock_fprog_kern	*orig_prog;	/* Original BPF program */
+	struct bpf_prog_stats __percpu *stats;
+	int __percpu		*active;
 	unsigned int		(*bpf_func)(const void *ctx,
 					    const struct bpf_insn *insn);
+	struct bpf_prog_aux	*aux;		/* Auxiliary fields */
+	struct sock_fprog_kern	*orig_prog;	/* Original BPF program */
 	/* Instructions for interpreter */
 	struct sock_filter	insns[0];
 	struct bpf_insn		insnsi[];
@@ -579,7 +606,7 @@ DECLARE_STATIC_KEY_FALSE(bpf_stats_enabled_key);
 		struct bpf_prog_stats *__stats;				\
 		u64 __start = sched_clock();				\
 		__ret = dfunc(ctx, (prog)->insnsi, (prog)->bpf_func);	\
-		__stats = this_cpu_ptr(prog->aux->stats);		\
+		__stats = this_cpu_ptr(prog->stats);			\
 		u64_stats_update_begin(&__stats->syncp);		\
 		__stats->cnt++;						\
 		__stats->nsecs += sched_clock() - __start;		\
@@ -864,8 +891,7 @@ void bpf_prog_free_linfo(struct bpf_prog *prog);
 void bpf_prog_fill_jited_linfo(struct bpf_prog *prog,
 			       const u32 *insn_to_jit_off);
 int bpf_prog_alloc_jited_linfo(struct bpf_prog *prog);
-void bpf_prog_free_jited_linfo(struct bpf_prog *prog);
-void bpf_prog_free_unused_jited_linfo(struct bpf_prog *prog);
+void bpf_prog_jit_attempt_done(struct bpf_prog *prog);
 
 struct bpf_prog *bpf_prog_alloc(unsigned int size, gfp_t gfp_extra_flags);
 struct bpf_prog *bpf_prog_alloc_no_stats(unsigned int size, gfp_t gfp_extra_flags);
@@ -906,6 +932,7 @@ u64 __bpf_call_base(u64 r1, u64 r2, u64 r3, u64 r4, u64 r5);
 struct bpf_prog *bpf_int_jit_compile(struct bpf_prog *prog);
 void bpf_jit_compile(struct bpf_prog *prog);
 bool bpf_jit_needs_zext(void);
+bool bpf_jit_supports_kfunc_call(void);
 bool bpf_helper_changes_pkt_data(void *func);
 
 static inline bool bpf_dump_raw_ok(const struct cred *cred)

include/linux/module.h

@@ -481,6 +481,10 @@ struct module {
 	unsigned int num_bpf_raw_events;
 	struct bpf_raw_event_map *bpf_raw_events;
 #endif
+#ifdef CONFIG_DEBUG_INFO_BTF_MODULES
+	unsigned int btf_data_size;
+	void *btf_data;
+#endif
 #ifdef CONFIG_JUMP_LABEL
 	struct jump_entry *jump_entries;
 	unsigned int num_jump_entries;

include/uapi/linux/bpf.h

@@ -19,7 +19,8 @@
 
 /* ld/ldx fields */
 #define BPF_DW		0x18	/* double word (64-bit) */
-#define BPF_XADD	0xc0	/* exclusive add */
+#define BPF_ATOMIC	0xc0	/* atomic memory ops - op type in immediate */
+#define BPF_XADD	0xc0	/* exclusive add - legacy name */
 
 /* alu/jmp fields */
 #define BPF_MOV		0xb0	/* mov reg to reg */
@@ -43,6 +44,11 @@
 #define BPF_CALL	0x80	/* function call */
 #define BPF_EXIT	0x90	/* function return */
 
+/* atomic op type fields (stored in immediate) */
+#define BPF_FETCH	0x01	/* not an opcode on its own, used to build others */
+#define BPF_XCHG	(0xe0 | BPF_FETCH)	/* atomic exchange */
+#define BPF_CMPXCHG	(0xf0 | BPF_FETCH)	/* atomic compare-and-write */
+
 /* Register numbers */
 enum {
 	BPF_REG_0 = 0,
@@ -100,6 +106,7 @@ enum bpf_cmd {
 	BPF_PROG_ATTACH,
 	BPF_PROG_DETACH,
 	BPF_PROG_TEST_RUN,
+	BPF_PROG_RUN = BPF_PROG_TEST_RUN,
 	BPF_PROG_GET_NEXT_ID,
 	BPF_MAP_GET_NEXT_ID,
 	BPF_PROG_GET_FD_BY_ID,
@@ -200,6 +207,7 @@ enum bpf_prog_type {
 	BPF_PROG_TYPE_LSM,
 	BPF_PROG_TYPE_SK_LOOKUP,
 	BPF_PROG_TYPE_SCHED,
+	BPF_PROG_TYPE_SYSCALL, /* a program that can execute syscalls */
 };
 
 enum bpf_attach_type {
@@ -360,8 +368,8 @@ enum bpf_link_type {
 /* When BPF ldimm64's insn[0].src_reg != 0 then this can have
  * the following extensions:
  *
- * insn[0].src_reg:  BPF_PSEUDO_MAP_FD
- * insn[0].imm:      map fd
+ * insn[0].src_reg:  BPF_PSEUDO_MAP_[FD|IDX]
+ * insn[0].imm:      map fd or fd_idx
  * insn[1].imm:      0
  * insn[0].off:      0
  * insn[1].off:      0
@@ -369,15 +377,19 @@ enum bpf_link_type {
  * verifier type:    CONST_PTR_TO_MAP
  */
 #define BPF_PSEUDO_MAP_FD	1
-/* insn[0].src_reg:  BPF_PSEUDO_MAP_VALUE
- * insn[0].imm:      map fd
+#define BPF_PSEUDO_MAP_IDX	5
+
+/* insn[0].src_reg:  BPF_PSEUDO_MAP_[IDX_]VALUE
+ * insn[0].imm:      map fd or fd_idx
  * insn[1].imm:      offset into value
  * insn[0].off:      0
  * insn[1].off:      0
  * ldimm64 rewrite:  address of map[0]+offset
  * verifier type:    PTR_TO_MAP_VALUE
  */
-#define BPF_PSEUDO_MAP_VALUE	2
+#define BPF_PSEUDO_MAP_VALUE		2
+#define BPF_PSEUDO_MAP_IDX_VALUE	6
+
 /* insn[0].src_reg:  BPF_PSEUDO_BTF_ID
  * insn[0].imm:      kernel btd id of VAR
  * insn[1].imm:      0
@@ -388,11 +400,24 @@ enum bpf_link_type {
  *                   is struct/union.
  */
 #define BPF_PSEUDO_BTF_ID	3
+/* insn[0].src_reg:  BPF_PSEUDO_FUNC
+ * insn[0].imm:      insn offset to the func
+ * insn[1].imm:      0
+ * insn[0].off:      0
+ * insn[1].off:      0
+ * ldimm64 rewrite:  address of the function
+ * verifier type:    PTR_TO_FUNC.
+ */
+#define BPF_PSEUDO_FUNC		4
 
 /* when bpf_call->src_reg == BPF_PSEUDO_CALL, bpf_call->imm == pc-relative
  * offset to another bpf function
  */
 #define BPF_PSEUDO_CALL		1
+/* when bpf_call->src_reg == BPF_PSEUDO_KFUNC_CALL,
+ * bpf_call->imm == btf_id of a BTF_KIND_FUNC in the running kernel
+ */
+#define BPF_PSEUDO_KFUNC_CALL	2
 
 /* flags for BPF_MAP_UPDATE_ELEM command */
 enum {
@@ -558,7 +583,16 @@ union bpf_attr {
 		__aligned_u64	line_info;	/* line info */
 		__u32		line_info_cnt;	/* number of bpf_line_info records */
 		__u32		attach_btf_id;	/* in-kernel BTF type id to attach to */
-		__u32		attach_prog_fd; /* 0 to attach to vmlinux */
+		union {
+			/* valid prog_fd to attach to bpf prog */
+			__u32		attach_prog_fd;
+			/* or valid module BTF object fd or 0 to attach to vmlinux */
+			__u32		attach_btf_obj_fd;
+		};
+		__u32		core_relo_cnt;	/* number of bpf_core_relo */
+		__aligned_u64	fd_array;	/* array of FDs */
+		__aligned_u64	core_relos;
+		__u32		core_relo_rec_size; /* sizeof(struct bpf_core_relo) */
 	};
 
 	struct { /* anonymous struct used by BPF_OBJ_* commands */
@@ -2444,7 +2478,7 @@ union bpf_attr {
  *		running simultaneously.
  *
  *		A user should care about the synchronization by himself.
- *		For example, by using the **BPF_STX_XADD** instruction to alter
+ *		For example, by using the **BPF_ATOMIC** instructions to alter
  *		the shared data.
  *	Return
  *		A pointer to the local storage area.
@@ -2989,10 +3023,10 @@ union bpf_attr {
  * 		string length is larger than *size*, just *size*-1 bytes are
  * 		copied and the last byte is set to NUL.
  *
- * 		On success, the length of the copied string is returned. This
- * 		makes this helper useful in tracing programs for reading
- * 		strings, and more importantly to get its length at runtime. See
- * 		the following snippet:
+ * 		On success, returns the number of bytes that were written,
+ * 		including the terminal NUL. This makes this helper useful in
+ * 		tracing programs for reading strings, and more importantly to
+ * 		get its length at runtime. See the following snippet:
  *
  * 		::
  *
@@ -3020,7 +3054,7 @@ union bpf_attr {
  * 		**->mm->env_start**: using this helper and the return value,
  * 		one can quickly iterate at the right offset of the memory area.
  * 	Return
- * 		On success, the strictly positive length of the string,
+ * 		On success, the strictly positive length of the output string,
  * 		including the trailing NUL character. On error, a negative
  * 		value.
  *
@@ -3312,12 +3346,20 @@ union bpf_attr {
  * 		of new data availability is sent.
  * 		If **BPF_RB_FORCE_WAKEUP** is specified in *flags*, notification
  * 		of new data availability is sent unconditionally.
+ * 		If **0** is specified in *flags*, an adaptive notification
+ * 		of new data availability is sent.
+ *
+ * 		An adaptive notification is a notification sent whenever the user-space
+ * 		process has caught up and consumed all available payloads. In case the user-space
+ * 		process is still processing a previous payload, then no notification is needed
+ * 		as it will process the newly added payload automatically.
  * 	Return
  * 		0 on success, or a negative error in case of failure.
  *
  * void *bpf_ringbuf_reserve(void *ringbuf, u64 size, u64 flags)
  * 	Description
  * 		Reserve *size* bytes of payload in a ring buffer *ringbuf*.
+ * 		*flags* must be 0.
  * 	Return
  * 		Valid pointer with *size* bytes of memory available; NULL,
  * 		otherwise.
@@ -3329,6 +3371,10 @@ union bpf_attr {
  * 		of new data availability is sent.
  * 		If **BPF_RB_FORCE_WAKEUP** is specified in *flags*, notification
  * 		of new data availability is sent unconditionally.
+ * 		If **0** is specified in *flags*, an adaptive notification
+ * 		of new data availability is sent.
+ *
+ * 		See 'bpf_ringbuf_output()' for the definition of adaptive notification.
  * 	Return
  * 		Nothing. Always succeeds.
  *
@@ -3339,6 +3385,10 @@ union bpf_attr {
  * 		of new data availability is sent.
  * 		If **BPF_RB_FORCE_WAKEUP** is specified in *flags*, notification
  * 		of new data availability is sent unconditionally.
+ * 		If **0** is specified in *flags*, an adaptive notification
+ * 		of new data availability is sent.
+ *
+ * 		See 'bpf_ringbuf_output()' for the definition of adaptive notification.
  * 	Return
  * 		Nothing. Always succeeds.
  *
@@ -3912,6 +3962,94 @@ union bpf_attr {
  *		set cpus_ptr in task.
  *	Return
  *		0 on success, or a negative error in case of failure.
+ * long bpf_for_each_map_elem(struct bpf_map *map, void *callback_fn, void *callback_ctx, u64 flags)
+ *	Description
+ *		For each element in **map**, call **callback_fn** function with
+ *		**map**, **callback_ctx** and other map-specific parameters.
+ *		The **callback_fn** should be a static function and
+ *		the **callback_ctx** should be a pointer to the stack.
+ *		The **flags** is used to control certain aspects of the helper.
+ *		Currently, the **flags** must be 0.
+ *
+ *		The following are a list of supported map types and their
+ *		respective expected callback signatures:
+ *
+ *		BPF_MAP_TYPE_HASH, BPF_MAP_TYPE_PERCPU_HASH,
+ *		BPF_MAP_TYPE_LRU_HASH, BPF_MAP_TYPE_LRU_PERCPU_HASH,
+ *		BPF_MAP_TYPE_ARRAY, BPF_MAP_TYPE_PERCPU_ARRAY
+ *
+ *		long (\*callback_fn)(struct bpf_map \*map, const void \*key, void \*value, void \*ctx);
+ *
+ *		For per_cpu maps, the map_value is the value on the cpu where the
+ *		bpf_prog is running.
+ *
+ *		If **callback_fn** return 0, the helper will continue to the next
+ *		element. If return value is 1, the helper will skip the rest of
+ *		elements and return. Other return values are not used now.
+ *
+ *	Return
+ *		The number of traversed map elements for success, **-EINVAL** for
+ *		invalid **flags**.
+ *
+ * long bpf_snprintf(char *str, u32 str_size, const char *fmt, u64 *data, u32 data_len)
+ *	Description
+ *		Outputs a string into the **str** buffer of size **str_size**
+ *		based on a format string stored in a read-only map pointed by
+ *		**fmt**.
+ *
+ *		Each format specifier in **fmt** corresponds to one u64 element
+ *		in the **data** array. For strings and pointers where pointees
+ *		are accessed, only the pointer values are stored in the *data*
+ *		array. The *data_len* is the size of *data* in bytes.
+ *
+ *		Formats **%s** and **%p{i,I}{4,6}** require to read kernel
+ *		memory. Reading kernel memory may fail due to either invalid
+ *		address or valid address but requiring a major memory fault. If
+ *		reading kernel memory fails, the string for **%s** will be an
+ *		empty string, and the ip address for **%p{i,I}{4,6}** will be 0.
+ *		Not returning error to bpf program is consistent with what
+ *		**bpf_trace_printk**\ () does for now.
+ *
+ *	Return
+ *		The strictly positive length of the formatted string, including
+ *		the trailing zero character. If the return value is greater than
+ *		**str_size**, **str** contains a truncated string, guaranteed to
+ *		be zero-terminated except when **str_size** is 0.
+ *
+ *		Or **-EBUSY** if the per-CPU memory copy buffer is busy.
+ *
+ * long bpf_sys_bpf(u32 cmd, void *attr, u32 attr_size)
+ * 	Description
+ * 		Execute bpf syscall with given arguments.
+ * 	Return
+ * 		A syscall result.
+ *
+ * long bpf_btf_find_by_name_kind(char *name, int name_sz, u32 kind, int flags)
+ * 	Description
+ * 		Find BTF type with given name and kind in vmlinux BTF or in module's BTFs.
+ * 	Return
+ * 		Returns btf_id and btf_obj_fd in lower and upper 32 bits.
+ *
+ * long bpf_sys_close(u32 fd)
+ * 	Description
+ * 		Execute close syscall for given FD.
+ * 	Return
+ * 		A syscall result.
+ *
+ * long bpf_kallsyms_lookup_name(const char *name, int name_sz, int flags, u64 *res)
+ *	Description
+ *		Get the address of a kernel symbol, returned in *res*. *res* is
+ *		set to 0 if the symbol is not found.
+ *	Return
+ *		On success, zero. On error, a negative value.
+ *
+ *		**-EINVAL** if *flags* is not zero.
+ *
+ *		**-EINVAL** if string *name* is not the same size as *name_sz*.
+ *
+ *		**-ENOENT** if symbol is not found.
+ *
+ *		**-EPERM** if caller does not have permission to obtain kernel address.
  */
 #define __BPF_FUNC_MAPPER(FN)		\
 	FN(unspec),			\
@@ -4091,6 +4229,12 @@ union bpf_attr {
 	FN(cpumask_op),			\
 	FN(cpus_share_cache),		\
 	FN(sched_set_task_cpus_ptr),	\
+	FN(for_each_map_elem),		\
+	FN(snprintf),			\
+	FN(sys_bpf),			\
+	FN(btf_find_by_name_kind),	\
+	FN(sys_close),			\
+	FN(kallsyms_lookup_name),	\
 	/* */
 
 /* integer value in 'imm' field of BPF_CALL instruction selects which helper
@@ -4587,6 +4731,8 @@ struct bpf_prog_info {
 	__aligned_u64 prog_tags;
 	__u64 run_time_ns;
 	__u64 run_cnt;
+	__u64 recursion_misses;
+	__u32 verified_insns;
 } __attribute__((aligned(8)));
 
 struct bpf_map_info {
@@ -4610,6 +4756,9 @@ struct bpf_btf_info {
 	__aligned_u64 btf;
 	__u32 btf_size;
 	__u32 id;
+	__aligned_u64 name;
+	__u32 name_len;
+	__u32 kernel_btf;
 } __attribute__((aligned(8)));
 
 struct bpf_link_info {
@@ -4623,6 +4772,8 @@ struct bpf_link_info {
 		} raw_tracepoint;
 		struct {
 			__u32 attach_type;
+			__u32 target_obj_id; /* prog_id for PROG_EXT, otherwise btf object id */
+			__u32 target_btf_id; /* BTF type id inside the object */
 		} tracing;
 		struct {
 			__u64 cgroup_id;
@@ -5198,7 +5349,10 @@ struct bpf_pidns_info {
 
 /* User accessible data for SK_LOOKUP programs. Add new fields at the end. */
 struct bpf_sk_lookup {
-	__bpf_md_ptr(struct bpf_sock *, sk); /* Selected socket */
+	union {
+		__bpf_md_ptr(struct bpf_sock *, sk); /* Selected socket */
+		__u64 cookie; /* Non-zero if socket was selected in PROG_TEST_RUN */
+	};
 
 	__u32 family;		/* Protocol family (AF_INET, AF_INET6) */
 	__u32 protocol;		/* IP protocol (IPPROTO_TCP, IPPROTO_UDP) */
@@ -5240,4 +5394,78 @@ enum {
 	BTF_F_ZERO	=	(1ULL << 3),
 };
 
+/* bpf_core_relo_kind encodes which aspect of captured field/type/enum value
+ * has to be adjusted by relocations. It is emitted by llvm and passed to
+ * libbpf and later to the kernel.
+ */
+enum bpf_core_relo_kind {
+	BPF_CORE_FIELD_BYTE_OFFSET = 0,      /* field byte offset */
+	BPF_CORE_FIELD_BYTE_SIZE = 1,        /* field size in bytes */
+	BPF_CORE_FIELD_EXISTS = 2,           /* field existence in target kernel */
+	BPF_CORE_FIELD_SIGNED = 3,           /* field signedness (0 - unsigned, 1 - signed) */
+	BPF_CORE_FIELD_LSHIFT_U64 = 4,       /* bitfield-specific left bitshift */
+	BPF_CORE_FIELD_RSHIFT_U64 = 5,       /* bitfield-specific right bitshift */
+	BPF_CORE_TYPE_ID_LOCAL = 6,          /* type ID in local BPF object */
+	BPF_CORE_TYPE_ID_TARGET = 7,         /* type ID in target kernel */
+	BPF_CORE_TYPE_EXISTS = 8,            /* type existence in target kernel */
+	BPF_CORE_TYPE_SIZE = 9,              /* type size in bytes */
+	BPF_CORE_ENUMVAL_EXISTS = 10,        /* enum value existence in target kernel */
+	BPF_CORE_ENUMVAL_VALUE = 11,         /* enum value integer value */
+};
+
+/*
+ * "struct bpf_core_relo" is used to pass relocation data form LLVM to libbpf
+ * and from libbpf to the kernel.
+ *
+ * CO-RE relocation captures the following data:
+ * - insn_off - instruction offset (in bytes) within a BPF program that needs
+ *   its insn->imm field to be relocated with actual field info;
+ * - type_id - BTF type ID of the "root" (containing) entity of a relocatable
+ *   type or field;
+ * - access_str_off - offset into corresponding .BTF string section. String
+ *   interpretation depends on specific relocation kind:
+ *     - for field-based relocations, string encodes an accessed field using
+ *       a sequence of field and array indices, separated by colon (:). It's
+ *       conceptually very close to LLVM's getelementptr ([0]) instruction's
+ *       arguments for identifying offset to a field.
+ *     - for type-based relocations, strings is expected to be just "0";
+ *     - for enum value-based relocations, string contains an index of enum
+ *       value within its enum type;
+ * - kind - one of enum bpf_core_relo_kind;
+ *
+ * Example:
+ *   struct sample {
+ *       int a;
+ *       struct {
+ *           int b[10];
+ *       };
+ *   };
+ *
+ *   struct sample *s = ...;
+ *   int *x = &s->a;     // encoded as "0:0" (a is field #0)
+ *   int *y = &s->b[5];  // encoded as "0:1:0:5" (anon struct is field #1,
+ *                       // b is field #0 inside anon struct, accessing elem #5)
+ *   int *z = &s[10]->b; // encoded as "10:1" (ptr is used as an array)
+ *
+ * type_id for all relocs in this example will capture BTF type id of
+ * `struct sample`.
+ *
+ * Such relocation is emitted when using __builtin_preserve_access_index()
+ * Clang built-in, passing expression that captures field address, e.g.:
+ *
+ * bpf_probe_read(&dst, sizeof(dst),
+ *		  __builtin_preserve_access_index(&src->a.b.c));
+ *
+ * In this case Clang will emit field relocation recording necessary data to
+ * be able to find offset of embedded `a.b.c` field within `src` struct.
+ *
+ * [0] https://llvm.org/docs/LangRef.html#getelementptr-instruction
+ */
+struct bpf_core_relo {
+	__u32 insn_off;
+	__u32 type_id;
+	__u32 access_str_off;
+	enum bpf_core_relo_kind kind;
+};
+
 #endif /* _UAPI__LINUX_BPF_H__ */

include/uapi/linux/btf.h

@@ -43,7 +43,7 @@ struct btf_type {
 	 * "size" tells the size of the type it is describing.
 	 *
 	 * "type" is used by PTR, TYPEDEF, VOLATILE, CONST, RESTRICT,
-	 * FUNC, FUNC_PROTO and VAR.
+	 * FUNC, FUNC_PROTO, VAR, DECL_TAG and TYPE_TAG.
 	 * "type" is a type_id referring to another type.
 	 */
 	union {
@@ -52,28 +52,34 @@ struct btf_type {
 	};
 };
 
-#define BTF_INFO_KIND(info)	(((info) >> 24) & 0x0f)
+#define BTF_INFO_KIND(info)	(((info) >> 24) & 0x1f)
 #define BTF_INFO_VLEN(info)	((info) & 0xffff)
 #define BTF_INFO_KFLAG(info)	((info) >> 31)
 
-#define BTF_KIND_UNKN		0	/* Unknown	*/
-#define BTF_KIND_INT		1	/* Integer	*/
-#define BTF_KIND_PTR		2	/* Pointer	*/
-#define BTF_KIND_ARRAY		3	/* Array	*/
-#define BTF_KIND_STRUCT		4	/* Struct	*/
-#define BTF_KIND_UNION		5	/* Union	*/
-#define BTF_KIND_ENUM		6	/* Enumeration	*/
-#define BTF_KIND_FWD		7	/* Forward	*/
-#define BTF_KIND_TYPEDEF	8	/* Typedef	*/
-#define BTF_KIND_VOLATILE	9	/* Volatile	*/
-#define BTF_KIND_CONST		10	/* Const	*/
-#define BTF_KIND_RESTRICT	11	/* Restrict	*/
-#define BTF_KIND_FUNC		12	/* Function	*/
-#define BTF_KIND_FUNC_PROTO	13	/* Function Proto	*/
-#define BTF_KIND_VAR		14	/* Variable	*/
-#define BTF_KIND_DATASEC	15	/* Section	*/
-#define BTF_KIND_MAX		BTF_KIND_DATASEC
-#define NR_BTF_KINDS		(BTF_KIND_MAX + 1)
+enum {
+	BTF_KIND_UNKN		= 0,	/* Unknown	*/
+	BTF_KIND_INT		= 1,	/* Integer	*/
+	BTF_KIND_PTR		= 2,	/* Pointer	*/
+	BTF_KIND_ARRAY		= 3,	/* Array	*/
+	BTF_KIND_STRUCT		= 4,	/* Struct	*/
+	BTF_KIND_UNION		= 5,	/* Union	*/
+	BTF_KIND_ENUM		= 6,	/* Enumeration	*/
+	BTF_KIND_FWD		= 7,	/* Forward	*/
+	BTF_KIND_TYPEDEF	= 8,	/* Typedef	*/
+	BTF_KIND_VOLATILE	= 9,	/* Volatile	*/
+	BTF_KIND_CONST		= 10,	/* Const	*/
+	BTF_KIND_RESTRICT	= 11,	/* Restrict	*/
+	BTF_KIND_FUNC		= 12,	/* Function	*/
+	BTF_KIND_FUNC_PROTO	= 13,	/* Function Proto	*/
+	BTF_KIND_VAR		= 14,	/* Variable	*/
+	BTF_KIND_DATASEC	= 15,	/* Section	*/
+	BTF_KIND_FLOAT		= 16,	/* Floating point	*/
+	BTF_KIND_DECL_TAG	= 17,	/* Decl Tag */
+	BTF_KIND_TYPE_TAG	= 18,	/* Type Tag */
+
+	NR_BTF_KINDS,
+	BTF_KIND_MAX		= NR_BTF_KINDS - 1,
+};
 
 /* For some specific BTF_KIND, "struct btf_type" is immediately
  * followed by extra data.
@@ -169,4 +175,15 @@ struct btf_var_secinfo {
 	__u32	size;
 };
 
+/* BTF_KIND_DECL_TAG is followed by a single "struct btf_decl_tag" to describe
+ * additional information related to the tag applied location.
+ * If component_idx == -1, the tag is applied to a struct, union,
+ * variable or function. Otherwise, it is applied to a struct/union
+ * member or a func argument, and component_idx indicates which member
+ * or argument (0 ... vlen-1).
+ */
+struct btf_decl_tag {
+       __s32   component_idx;
+};
+
 #endif /* _UAPI__LINUX_BTF_H__ */

kernel/bpf/Makefile

@@ -36,3 +36,7 @@ obj-$(CONFIG_BPF_SYSCALL) += bpf_struct_ops.o
 obj-${CONFIG_BPF_LSM} += bpf_lsm.o
 endif
 obj-$(CONFIG_BPF_PRELOAD) += preload/
+
+obj-$(CONFIG_BPF_SYSCALL) += relo_core.o
+$(obj)/relo_core.o: $(srctree)/tools/lib/bpf/relo_core.c FORCE
+	$(call if_changed_rule,cc_o_c)

kernel/bpf/bpf_iter.c

@@ -459,15 +459,16 @@ bool bpf_link_is_iter(struct bpf_link *link)
 	return link->ops == &bpf_iter_link_lops;
 }
 
-int bpf_iter_link_attach(const union bpf_attr *attr, struct bpf_prog *prog)
+int bpf_iter_link_attach(const union bpf_attr *attr, bpfptr_t uattr,
+			 struct bpf_prog *prog)
 {
-	union bpf_iter_link_info __user *ulinfo;
 	struct bpf_link_primer link_primer;
 	struct bpf_iter_target_info *tinfo;
 	union bpf_iter_link_info linfo;
 	struct bpf_iter_link *link;
 	u32 prog_btf_id, linfo_len;
 	bool existed = false;
+	bpfptr_t ulinfo;
 	int err;
 
 	if (attr->link_create.target_fd || attr->link_create.flags)
@@ -475,18 +476,18 @@ int bpf_iter_link_attach(const union bpf_attr *attr, struct bpf_prog *prog)
 
 	memset(&linfo, 0, sizeof(union bpf_iter_link_info));
 
-	ulinfo = u64_to_user_ptr(attr->link_create.iter_info);
+	ulinfo = make_bpfptr(attr->link_create.iter_info, uattr.is_kernel);
 	linfo_len = attr->link_create.iter_info_len;
-	if (!ulinfo ^ !linfo_len)
+	if (bpfptr_is_null(ulinfo) ^ !linfo_len)
 		return -EINVAL;
 
-	if (ulinfo) {
+	if (!bpfptr_is_null(ulinfo)) {
 		err = bpf_check_uarg_tail_zero(ulinfo, sizeof(linfo),
 					       linfo_len);
 		if (err)
 			return err;
 		linfo_len = min_t(u32, linfo_len, sizeof(linfo));
-		if (copy_from_user(&linfo, ulinfo, linfo_len))
+		if (copy_from_bpfptr(&linfo, ulinfo, linfo_len))
 			return -EFAULT;
 	}
 
@@ -661,3 +662,19 @@ int bpf_iter_run_prog(struct bpf_prog *prog, void *ctx)
 	 */
 	return ret == 0 ? 0 : -EAGAIN;
 }
+
+BPF_CALL_4(bpf_for_each_map_elem, struct bpf_map *, map, void *, callback_fn,
+	   void *, callback_ctx, u64, flags)
+{
+	return map->ops->map_for_each_callback(map, callback_fn, callback_ctx, flags);
+}
+
+const struct bpf_func_proto bpf_for_each_map_elem_proto = {
+	.func		= bpf_for_each_map_elem,
+	.gpl_only	= false,
+	.ret_type	= RET_INTEGER,
+	.arg1_type	= ARG_CONST_MAP_PTR,
+	.arg2_type	= ARG_PTR_TO_FUNC,
+	.arg3_type	= ARG_PTR_TO_STACK_OR_NULL,
+	.arg4_type	= ARG_ANYTHING,
+};

kernel/bpf/bpf_struct_ops.c

@@ -161,7 +161,7 @@ void bpf_struct_ops_init(struct btf *btf, struct bpf_verifier_log *log)
 				break;
 			}
 
-			if (btf_member_bitfield_size(t, member)) {
+			if (__btf_member_bitfield_size(t, member)) {
 				pr_warn("bit field member %s in struct %s is not supported\n",
 					mname, st_ops->name);
 				break;
@@ -292,7 +292,7 @@ static int check_zero_holes(const struct btf_type *t, void *data)
 	const struct btf_type *mtype;
 
 	for_each_member(i, t, member) {
-		moff = btf_member_bit_offset(t, member) / 8;
+		moff = __btf_member_bit_offset(t, member) / 8;
 		if (moff > prev_mend &&
 		    memchr_inv(data + prev_mend, 0, moff - prev_mend))
 			return -EINVAL;
@@ -369,7 +369,7 @@ static int bpf_struct_ops_map_update_elem(struct bpf_map *map, void *key,
 		u32 moff;
 		u32 flags;
 
-		moff = btf_member_bit_offset(t, member) / 8;
+		moff = __btf_member_bit_offset(t, member) / 8;
 		ptype = btf_type_resolve_ptr(btf_vmlinux, member->type, NULL);
 		if (ptype == module_type) {
 			if (*(void **)(udata + moff))

kernel/bpf/disasm.c

@@ -19,16 +19,23 @@ static const char *__func_get_name(const struct bpf_insn_cbs *cbs,
 {
 	BUILD_BUG_ON(ARRAY_SIZE(func_id_str) != __BPF_FUNC_MAX_ID);
 
-	if (insn->src_reg != BPF_PSEUDO_CALL &&
+	if (!insn->src_reg &&
 	    insn->imm >= 0 && insn->imm < __BPF_FUNC_MAX_ID &&
 	    func_id_str[insn->imm])
 		return func_id_str[insn->imm];
 
-	if (cbs && cbs->cb_call)
-		return cbs->cb_call(cbs->private_data, insn);
+	if (cbs && cbs->cb_call) {
+		const char *res;
+
+		res = cbs->cb_call(cbs->private_data, insn);
+		if (res)
+			return res;
+	}
 
 	if (insn->src_reg == BPF_PSEUDO_CALL)
 		snprintf(buff, len, "%+d", insn->imm);
+	else if (insn->src_reg == BPF_PSEUDO_KFUNC_CALL)
+		snprintf(buff, len, "kernel-function");
 
 	return buff;
 }
@@ -80,6 +87,13 @@ const char *const bpf_alu_string[16] = {
 	[BPF_END >> 4]  = "endian",
 };
 
+static const char *const bpf_atomic_alu_string[16] = {
+	[BPF_ADD >> 4]  = "add",
+	[BPF_AND >> 4]  = "and",
+	[BPF_OR >> 4]  = "or",
+	[BPF_XOR >> 4]  = "or",
+};
+
 static const char *const bpf_ldst_string[] = {
 	[BPF_W >> 3]  = "u32",
 	[BPF_H >> 3]  = "u16",
@@ -153,14 +167,44 @@ void print_bpf_insn(const struct bpf_insn_cbs *cbs,
 				bpf_ldst_string[BPF_SIZE(insn->code) >> 3],
 				insn->dst_reg,
 				insn->off, insn->src_reg);
-		else if (BPF_MODE(insn->code) == BPF_XADD)
-			verbose(cbs->private_data, "(%02x) lock *(%s *)(r%d %+d) += r%d\n",
+		else if (BPF_MODE(insn->code) == BPF_ATOMIC &&
+			 (insn->imm == BPF_ADD || insn->imm == BPF_ADD ||
+			  insn->imm == BPF_OR || insn->imm == BPF_XOR)) {
+			verbose(cbs->private_data, "(%02x) lock *(%s *)(r%d %+d) %s r%d\n",
+				insn->code,
+				bpf_ldst_string[BPF_SIZE(insn->code) >> 3],
+				insn->dst_reg, insn->off,
+				bpf_alu_string[BPF_OP(insn->imm) >> 4],
+				insn->src_reg);
+		} else if (BPF_MODE(insn->code) == BPF_ATOMIC &&
+			   (insn->imm == (BPF_ADD | BPF_FETCH) ||
+			    insn->imm == (BPF_AND | BPF_FETCH) ||
+			    insn->imm == (BPF_OR | BPF_FETCH) ||
+			    insn->imm == (BPF_XOR | BPF_FETCH))) {
+			verbose(cbs->private_data, "(%02x) r%d = atomic%s_fetch_%s((%s *)(r%d %+d), r%d)\n",
+				insn->code, insn->src_reg,
+				BPF_SIZE(insn->code) == BPF_DW ? "64" : "",
+				bpf_atomic_alu_string[BPF_OP(insn->imm) >> 4],
+				bpf_ldst_string[BPF_SIZE(insn->code) >> 3],
+				insn->dst_reg, insn->off, insn->src_reg);
+		} else if (BPF_MODE(insn->code) == BPF_ATOMIC &&
+			   insn->imm == BPF_CMPXCHG) {
+			verbose(cbs->private_data, "(%02x) r0 = atomic%s_cmpxchg((%s *)(r%d %+d), r0, r%d)\n",
 				insn->code,
+				BPF_SIZE(insn->code) == BPF_DW ? "64" : "",
 				bpf_ldst_string[BPF_SIZE(insn->code) >> 3],
 				insn->dst_reg, insn->off,
 				insn->src_reg);
-		else
+		} else if (BPF_MODE(insn->code) == BPF_ATOMIC &&
+			   insn->imm == BPF_XCHG) {
+			verbose(cbs->private_data, "(%02x) r%d = atomic%s_xchg((%s *)(r%d %+d), r%d)\n",
+				insn->code, insn->src_reg,
+				BPF_SIZE(insn->code) == BPF_DW ? "64" : "",
+				bpf_ldst_string[BPF_SIZE(insn->code) >> 3],
+				insn->dst_reg, insn->off, insn->src_reg);
+		} else {
 			verbose(cbs->private_data, "BUG_%02x\n", insn->code);
+		}
 	} else if (class == BPF_ST) {
 		if (BPF_MODE(insn->code) == BPF_MEM) {
 			verbose(cbs->private_data, "(%02x) *(%s *)(r%d %+d) = %d\n",

kernel/bpf/hashtab.c

@@ -1122,7 +1122,7 @@ static int __htab_percpu_map_update_elem(struct bpf_map *map, void *key,
 		/* unknown flags */
 		return -EINVAL;
 
-	WARN_ON_ONCE(!rcu_read_lock_held());
+	WARN_ON_ONCE(!rcu_read_lock_held() && !rcu_read_lock_trace_held());
 
 	key_size = map->key_size;
 
@@ -1174,7 +1174,7 @@ static int __htab_lru_percpu_map_update_elem(struct bpf_map *map, void *key,
 		/* unknown flags */
 		return -EINVAL;
 
-	WARN_ON_ONCE(!rcu_read_lock_held());
+	WARN_ON_ONCE(!rcu_read_lock_held() && !rcu_read_lock_trace_held());
 
 	key_size = map->key_size;
 

kernel/bpf/preload/Makefile

 # SPDX-License-Identifier: GPL-2.0
 
 LIBBPF_SRCS = $(srctree)/tools/lib/bpf/
-LIBBPF_A = $(obj)/libbpf.a
-LIBBPF_OUT = $(abspath $(obj))
+LIBBPF_OUT = $(abspath $(obj))/libbpf
+LIBBPF_A = $(LIBBPF_OUT)/libbpf.a
+LIBBPF_DESTDIR = $(LIBBPF_OUT)
+LIBBPF_INCLUDE = $(LIBBPF_DESTDIR)/include
 
 # Although not in use by libbpf's Makefile, set $(O) so that the "dummy" test
 # in tools/scripts/Makefile.include always succeeds when building the kernel
 # with $(O) pointing to a relative path, as in "make O=build bindeb-pkg".
-$(LIBBPF_A):
-	$(Q)$(MAKE) -C $(LIBBPF_SRCS) O=$(LIBBPF_OUT)/ OUTPUT=$(LIBBPF_OUT)/ $(LIBBPF_OUT)/libbpf.a
+$(LIBBPF_A): | $(LIBBPF_OUT)
+	$(Q)$(MAKE) -C $(LIBBPF_SRCS) O=$(LIBBPF_OUT)/ OUTPUT=$(LIBBPF_OUT)/   \
+		DESTDIR=$(LIBBPF_DESTDIR) prefix=			       \
+		$(LIBBPF_OUT)/libbpf.a install_headers
+
+libbpf_hdrs: $(LIBBPF_A)
+
+.PHONY: libbpf_hdrs
+
+$(LIBBPF_OUT):
+	$(call msg,MKDIR,$@)
+	$(Q)mkdir -p $@
 
 userccflags += -I $(srctree)/tools/include/ -I $(srctree)/tools/include/uapi \
-	-I $(srctree)/tools/lib/ -Wno-unused-result
+	-I $(LIBBPF_INCLUDE) -Wno-unused-result
 
 userprogs := bpf_preload_umd
 
 clean-files := $(userprogs) bpf_helper_defs.h FEATURE-DUMP.libbpf staticobjs/ feature/
+clean-files += $(LIBBPF_OUT) $(LIBBPF_DESTDIR)
+
+$(obj)/iterators/iterators.o: | libbpf_hdrs
 
 bpf_preload_umd-objs := iterators/iterators.o
 bpf_preload_umd-userldlibs := $(LIBBPF_A) -lelf -lz

kernel/bpf/preload/iterators/Makefile

 # SPDX-License-Identifier: GPL-2.0
 OUTPUT := .output
+abs_out := $(abspath $(OUTPUT))
+
 CLANG ?= clang
 LLC ?= llc
 LLVM_STRIP ?= llvm-strip
+
+TOOLS_PATH := $(abspath ../../../../tools)
+BPFTOOL_SRC := $(TOOLS_PATH)/bpf/bpftool
+BPFTOOL_OUTPUT := $(abs_out)/bpftool
 DEFAULT_BPFTOOL := $(OUTPUT)/sbin/bpftool
 BPFTOOL ?= $(DEFAULT_BPFTOOL)
-LIBBPF_SRC := $(abspath ../../../../tools/lib/bpf)
-BPFOBJ := $(OUTPUT)/libbpf.a
-BPF_INCLUDE := $(OUTPUT)
-INCLUDES := -I$(OUTPUT) -I$(BPF_INCLUDE) -I$(abspath ../../../../tools/lib)        \
-       -I$(abspath ../../../../tools/include/uapi)
+
+LIBBPF_SRC := $(TOOLS_PATH)/lib/bpf
+LIBBPF_OUTPUT := $(abs_out)/libbpf
+LIBBPF_DESTDIR := $(LIBBPF_OUTPUT)
+LIBBPF_INCLUDE := $(LIBBPF_DESTDIR)/include
+BPFOBJ := $(LIBBPF_OUTPUT)/libbpf.a
+
+INCLUDES := -I$(OUTPUT) -I$(LIBBPF_INCLUDE) -I$(TOOLS_PATH)/include/uapi
 CFLAGS := -g -Wall
 
-abs_out := $(abspath $(OUTPUT))
 ifeq ($(V),1)
 Q =
 msg =
@@ -44,14 +52,18 @@ $(OUTPUT)/iterators.bpf.o: iterators.bpf.c $(BPFOBJ) | $(OUTPUT)
 		 -c $(filter %.c,$^) -o $@ &&				      \
 	$(LLVM_STRIP) -g $@
 
-$(OUTPUT):
+$(OUTPUT) $(LIBBPF_OUTPUT) $(BPFTOOL_OUTPUT):
 	$(call msg,MKDIR,$@)
-	$(Q)mkdir -p $(OUTPUT)
+	$(Q)mkdir -p $@
 
-$(BPFOBJ): $(wildcard $(LIBBPF_SRC)/*.[ch] $(LIBBPF_SRC)/Makefile) | $(OUTPUT)
+$(BPFOBJ): $(wildcard $(LIBBPF_SRC)/*.[ch] $(LIBBPF_SRC)/Makefile) | $(LIBBPF_OUTPUT)
 	$(Q)$(MAKE) $(submake_extras) -C $(LIBBPF_SRC)			       \
-		    OUTPUT=$(abspath $(dir $@))/ $(abspath $@)
+		    OUTPUT=$(abspath $(dir $@))/ prefix=		       \
+		    DESTDIR=$(LIBBPF_DESTDIR) $(abspath $@) install_headers
 
-$(DEFAULT_BPFTOOL):
-	$(Q)$(MAKE) $(submake_extras) -C ../../../../tools/bpf/bpftool			      \
-		    prefix= OUTPUT=$(abs_out)/ DESTDIR=$(abs_out) install
+$(DEFAULT_BPFTOOL): $(BPFOBJ) | $(BPFTOOL_OUTPUT)
+	$(Q)$(MAKE) $(submake_extras) -C $(BPFTOOL_SRC)			       \
+		    OUTPUT=$(BPFTOOL_OUTPUT)/				       \
+		    LIBBPF_OUTPUT=$(LIBBPF_OUTPUT)/			       \
+		    LIBBPF_DESTDIR=$(LIBBPF_DESTDIR)/			       \
+		    prefix= DESTDIR=$(abs_out)/ install-bin

kernel/bpf/preload/iterators/iterators.bpf.c

@@ -2,7 +2,6 @@
 /* Copyright (c) 2020 Facebook */
 #include <linux/bpf.h>
 #include <bpf/bpf_helpers.h>
-#include <bpf/bpf_tracing.h>
 #include <bpf/bpf_core_read.h>
 
 #pragma clang attribute push (__attribute__((preserve_access_index)), apply_to = record)

kernel/bpf/sysfs_btf.c

@@ -26,7 +26,7 @@ static struct bin_attribute bin_attr_btf_vmlinux __ro_after_init = {
 	.read = btf_vmlinux_read,
 };
 
-static struct kobject *btf_kobj;
+struct kobject *btf_kobj;
 
 static int __init btf_vmlinux_init(void)
 {

lib/Kconfig.debug

@@ -274,6 +274,15 @@ config DEBUG_INFO_BTF
 	  Turning this on expects presence of pahole tool, which will convert
 	  DWARF type info into equivalent deduplicated BTF type info.
 
+config PAHOLE_HAS_SPLIT_BTF
+	def_bool $(success, test `$(PAHOLE) --version | sed -E 's/v([0-9]+)\.([0-9]+)/\1\2/'` -ge "119")
+
+config DEBUG_INFO_BTF_MODULES
+	def_bool y
+	depends on DEBUG_INFO_BTF && MODULES && PAHOLE_HAS_SPLIT_BTF
+	help
+	  Generate compact split BTF type information for kernel modules.
+
 config GDB_SCRIPTS
 	bool "Provide GDB scripts for kernel debugging"
 	help

tools/lib/bpf/.gitignore

 # SPDX-License-Identifier: GPL-2.0-only
-libbpf_version.h
 libbpf.pc
-FEATURE-DUMP.libbpf
 libbpf.so.*
 TAGS
 tags