Adding upstream version 6.1.76.upstream/6.1.76

Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>

1 files changed, 2597 insertions, 0 deletions

diff --git a/arch/x86/net/bpf_jit_comp.c b/arch/x86/net/bpf_jit_comp.c
new file mode 100644
index 000000000..b69aee624
--- /dev/null
+++ b/arch/x86/net/bpf_jit_comp.c
@@ -0,0 +1,2597 @@
+// SPDX-License-Identifier: GPL-2.0-only
+/*
+ * BPF JIT compiler
+ *
+ * Copyright (C) 2011-2013 Eric Dumazet (eric.dumazet@gmail.com)
+ * Copyright (c) 2011-2014 PLUMgrid, http://plumgrid.com
+ */
+#include <linux/netdevice.h>
+#include <linux/filter.h>
+#include <linux/if_vlan.h>
+#include <linux/bpf.h>
+#include <linux/memory.h>
+#include <linux/sort.h>
+#include <asm/extable.h>
+#include <asm/set_memory.h>
+#include <asm/nospec-branch.h>
+#include <asm/text-patching.h>
+
+static u8 *emit_code(u8 *ptr, u32 bytes, unsigned int len)
+{
+	if (len == 1)
+		*ptr = bytes;
+	else if (len == 2)
+		*(u16 *)ptr = bytes;
+	else {
+		*(u32 *)ptr = bytes;
+		barrier();
+	}
+	return ptr + len;
+}
+
+#define EMIT(bytes, len) \
+	do { prog = emit_code(prog, bytes, len); } while (0)
+
+#define EMIT1(b1)		EMIT(b1, 1)
+#define EMIT2(b1, b2)		EMIT((b1) + ((b2) << 8), 2)
+#define EMIT3(b1, b2, b3)	EMIT((b1) + ((b2) << 8) + ((b3) << 16), 3)
+#define EMIT4(b1, b2, b3, b4)   EMIT((b1) + ((b2) << 8) + ((b3) << 16) + ((b4) << 24), 4)
+
+#define EMIT1_off32(b1, off) \
+	do { EMIT1(b1); EMIT(off, 4); } while (0)
+#define EMIT2_off32(b1, b2, off) \
+	do { EMIT2(b1, b2); EMIT(off, 4); } while (0)
+#define EMIT3_off32(b1, b2, b3, off) \
+	do { EMIT3(b1, b2, b3); EMIT(off, 4); } while (0)
+#define EMIT4_off32(b1, b2, b3, b4, off) \
+	do { EMIT4(b1, b2, b3, b4); EMIT(off, 4); } while (0)
+
+#ifdef CONFIG_X86_KERNEL_IBT
+#define EMIT_ENDBR()	EMIT(gen_endbr(), 4)
+#else
+#define EMIT_ENDBR()
+#endif
+
+static bool is_imm8(int value)
+{
+	return value <= 127 && value >= -128;
+}
+
+static bool is_simm32(s64 value)
+{
+	return value == (s64)(s32)value;
+}
+
+static bool is_uimm32(u64 value)
+{
+	return value == (u64)(u32)value;
+}
+
+/* mov dst, src */
+#define EMIT_mov(DST, SRC)								 \
+	do {										 \
+		if (DST != SRC)								 \
+			EMIT3(add_2mod(0x48, DST, SRC), 0x89, add_2reg(0xC0, DST, SRC)); \
+	} while (0)
+
+static int bpf_size_to_x86_bytes(int bpf_size)
+{
+	if (bpf_size == BPF_W)
+		return 4;
+	else if (bpf_size == BPF_H)
+		return 2;
+	else if (bpf_size == BPF_B)
+		return 1;
+	else if (bpf_size == BPF_DW)
+		return 4; /* imm32 */
+	else
+		return 0;
+}
+
+/*
+ * List of x86 cond jumps opcodes (. + s8)
+ * Add 0x10 (and an extra 0x0f) to generate far jumps (. + s32)
+ */
+#define X86_JB  0x72
+#define X86_JAE 0x73
+#define X86_JE  0x74
+#define X86_JNE 0x75
+#define X86_JBE 0x76
+#define X86_JA  0x77
+#define X86_JL  0x7C
+#define X86_JGE 0x7D
+#define X86_JLE 0x7E
+#define X86_JG  0x7F
+
+/* Pick a register outside of BPF range for JIT internal work */
+#define AUX_REG (MAX_BPF_JIT_REG + 1)
+#define X86_REG_R9 (MAX_BPF_JIT_REG + 2)
+
+/*
+ * The following table maps BPF registers to x86-64 registers.
+ *
+ * x86-64 register R12 is unused, since if used as base address
+ * register in load/store instructions, it always needs an
+ * extra byte of encoding and is callee saved.
+ *
+ * x86-64 register R9 is not used by BPF programs, but can be used by BPF
+ * trampoline. x86-64 register R10 is used for blinding (if enabled).
+ */
+static const int reg2hex[] = {
+	[BPF_REG_0] = 0,  /* RAX */
+	[BPF_REG_1] = 7,  /* RDI */
+	[BPF_REG_2] = 6,  /* RSI */
+	[BPF_REG_3] = 2,  /* RDX */
+	[BPF_REG_4] = 1,  /* RCX */
+	[BPF_REG_5] = 0,  /* R8  */
+	[BPF_REG_6] = 3,  /* RBX callee saved */
+	[BPF_REG_7] = 5,  /* R13 callee saved */
+	[BPF_REG_8] = 6,  /* R14 callee saved */
+	[BPF_REG_9] = 7,  /* R15 callee saved */
+	[BPF_REG_FP] = 5, /* RBP readonly */
+	[BPF_REG_AX] = 2, /* R10 temp register */
+	[AUX_REG] = 3,    /* R11 temp register */
+	[X86_REG_R9] = 1, /* R9 register, 6th function argument */
+};
+
+static const int reg2pt_regs[] = {
+	[BPF_REG_0] = offsetof(struct pt_regs, ax),
+	[BPF_REG_1] = offsetof(struct pt_regs, di),
+	[BPF_REG_2] = offsetof(struct pt_regs, si),
+	[BPF_REG_3] = offsetof(struct pt_regs, dx),
+	[BPF_REG_4] = offsetof(struct pt_regs, cx),
+	[BPF_REG_5] = offsetof(struct pt_regs, r8),
+	[BPF_REG_6] = offsetof(struct pt_regs, bx),
+	[BPF_REG_7] = offsetof(struct pt_regs, r13),
+	[BPF_REG_8] = offsetof(struct pt_regs, r14),
+	[BPF_REG_9] = offsetof(struct pt_regs, r15),
+};
+
+/*
+ * is_ereg() == true if BPF register 'reg' maps to x86-64 r8..r15
+ * which need extra byte of encoding.
+ * rax,rcx,...,rbp have simpler encoding
+ */
+static bool is_ereg(u32 reg)
+{
+	return (1 << reg) & (BIT(BPF_REG_5) |
+			     BIT(AUX_REG) |
+			     BIT(BPF_REG_7) |
+			     BIT(BPF_REG_8) |
+			     BIT(BPF_REG_9) |
+			     BIT(X86_REG_R9) |
+			     BIT(BPF_REG_AX));
+}
+
+/*
+ * is_ereg_8l() == true if BPF register 'reg' is mapped to access x86-64
+ * lower 8-bit registers dil,sil,bpl,spl,r8b..r15b, which need extra byte
+ * of encoding. al,cl,dl,bl have simpler encoding.
+ */
+static bool is_ereg_8l(u32 reg)
+{
+	return is_ereg(reg) ||
+	    (1 << reg) & (BIT(BPF_REG_1) |
+			  BIT(BPF_REG_2) |
+			  BIT(BPF_REG_FP));
+}
+
+static bool is_axreg(u32 reg)
+{
+	return reg == BPF_REG_0;
+}
+
+/* Add modifiers if 'reg' maps to x86-64 registers R8..R15 */
+static u8 add_1mod(u8 byte, u32 reg)
+{
+	if (is_ereg(reg))
+		byte |= 1;
+	return byte;
+}
+
+static u8 add_2mod(u8 byte, u32 r1, u32 r2)
+{
+	if (is_ereg(r1))
+		byte |= 1;
+	if (is_ereg(r2))
+		byte |= 4;
+	return byte;
+}
+
+/* Encode 'dst_reg' register into x86-64 opcode 'byte' */
+static u8 add_1reg(u8 byte, u32 dst_reg)
+{
+	return byte + reg2hex[dst_reg];
+}
+
+/* Encode 'dst_reg' and 'src_reg' registers into x86-64 opcode 'byte' */
+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 */
+	memset(area, 0xcc, size);
+}
+
+int bpf_arch_text_invalidate(void *dst, size_t len)
+{
+	return IS_ERR_OR_NULL(text_poke_set(dst, 0xcc, len));
+}
+
+struct jit_context {
+	int cleanup_addr; /* Epilogue code offset */
+
+	/*
+	 * Program specific offsets of labels in the code; these rely on the
+	 * JIT doing at least 2 passes, recording the position on the first
+	 * pass, only to generate the correct offset on the second pass.
+	 */
+	int tail_call_direct_label;
+	int tail_call_indirect_label;
+};
+
+/* Maximum number of bytes emitted while JITing one eBPF insn */
+#define BPF_MAX_INSN_SIZE	128
+#define BPF_INSN_SAFETY		64
+
+/* Number of bytes emit_patch() needs to generate instructions */
+#define X86_PATCH_SIZE		5
+/* Number of bytes that will be skipped on tailcall */
+#define X86_TAIL_CALL_OFFSET	(11 + ENDBR_INSN_SIZE)
+
+static void push_callee_regs(u8 **pprog, bool *callee_regs_used)
+{
+	u8 *prog = *pprog;
+
+	if (callee_regs_used[0])
+		EMIT1(0x53);         /* push rbx */
+	if (callee_regs_used[1])
+		EMIT2(0x41, 0x55);   /* push r13 */
+	if (callee_regs_used[2])
+		EMIT2(0x41, 0x56);   /* push r14 */
+	if (callee_regs_used[3])
+		EMIT2(0x41, 0x57);   /* push r15 */
+	*pprog = prog;
+}
+
+static void pop_callee_regs(u8 **pprog, bool *callee_regs_used)
+{
+	u8 *prog = *pprog;
+
+	if (callee_regs_used[3])
+		EMIT2(0x41, 0x5F);   /* pop r15 */
+	if (callee_regs_used[2])
+		EMIT2(0x41, 0x5E);   /* pop r14 */
+	if (callee_regs_used[1])
+		EMIT2(0x41, 0x5D);   /* pop r13 */
+	if (callee_regs_used[0])
+		EMIT1(0x5B);         /* pop rbx */
+	*pprog = prog;
+}
+
+/*
+ * Emit x86-64 prologue code for BPF program.
+ * bpf_tail_call helper will skip the first X86_TAIL_CALL_OFFSET bytes
+ * while jumping to another program
+ */
+static void emit_prologue(u8 **pprog, u32 stack_depth, bool ebpf_from_cbpf,
+			  bool tail_call_reachable, bool is_subprog)
+{
+	u8 *prog = *pprog;
+
+	/* BPF trampoline can be made to work without these nops,
+	 * but let's waste 5 bytes for now and optimize later
+	 */
+	EMIT_ENDBR();
+	memcpy(prog, x86_nops[5], X86_PATCH_SIZE);
+	prog += X86_PATCH_SIZE;
+	if (!ebpf_from_cbpf) {
+		if (tail_call_reachable && !is_subprog)
+			EMIT2(0x31, 0xC0); /* xor eax, eax */
+		else
+			EMIT2(0x66, 0x90); /* nop2 */
+	}
+	EMIT1(0x55);             /* push rbp */
+	EMIT3(0x48, 0x89, 0xE5); /* mov rbp, rsp */
+
+	/* X86_TAIL_CALL_OFFSET is here */
+	EMIT_ENDBR();
+
+	/* sub rsp, rounded_stack_depth */
+	if (stack_depth)
+		EMIT3_off32(0x48, 0x81, 0xEC, round_up(stack_depth, 8));
+	if (tail_call_reachable)
+		EMIT1(0x50);         /* push rax */
+	*pprog = prog;
+}
+
+static int emit_patch(u8 **pprog, void *func, void *ip, u8 opcode)
+{
+	u8 *prog = *pprog;
+	s64 offset;
+
+	offset = func - (ip + X86_PATCH_SIZE);
+	if (!is_simm32(offset)) {
+		pr_err("Target call %p is out of range\n", func);
+		return -ERANGE;
+	}
+	EMIT1_off32(opcode, offset);
+	*pprog = prog;
+	return 0;
+}
+
+static int emit_call(u8 **pprog, void *func, void *ip)
+{
+	return emit_patch(pprog, func, ip, 0xE8);
+}
+
+static int emit_jump(u8 **pprog, void *func, void *ip)
+{
+	return emit_patch(pprog, func, ip, 0xE9);
+}
+
+static int __bpf_arch_text_poke(void *ip, enum bpf_text_poke_type t,
+				void *old_addr, void *new_addr)
+{
+	const u8 *nop_insn = x86_nops[5];
+	u8 old_insn[X86_PATCH_SIZE];
+	u8 new_insn[X86_PATCH_SIZE];
+	u8 *prog;
+	int ret;
+
+	memcpy(old_insn, nop_insn, X86_PATCH_SIZE);
+	if (old_addr) {
+		prog = old_insn;
+		ret = t == BPF_MOD_CALL ?
+		      emit_call(&prog, old_addr, ip) :
+		      emit_jump(&prog, old_addr, ip);
+		if (ret)
+			return ret;
+	}
+
+	memcpy(new_insn, nop_insn, X86_PATCH_SIZE);
+	if (new_addr) {
+		prog = new_insn;
+		ret = t == BPF_MOD_CALL ?
+		      emit_call(&prog, new_addr, ip) :
+		      emit_jump(&prog, new_addr, ip);
+		if (ret)
+			return ret;
+	}
+
+	ret = -EBUSY;
+	mutex_lock(&text_mutex);
+	if (memcmp(ip, old_insn, X86_PATCH_SIZE))
+		goto out;
+	ret = 1;
+	if (memcmp(ip, new_insn, X86_PATCH_SIZE)) {
+		text_poke_bp(ip, new_insn, X86_PATCH_SIZE, NULL);
+		ret = 0;
+	}
+out:
+	mutex_unlock(&text_mutex);
+	return ret;
+}
+
+int bpf_arch_text_poke(void *ip, enum bpf_text_poke_type t,
+		       void *old_addr, void *new_addr)
+{
+	if (!is_kernel_text((long)ip) &&
+	    !is_bpf_text_address((long)ip))
+		/* BPF poking in modules is not supported */
+		return -EINVAL;
+
+	/*
+	 * See emit_prologue(), for IBT builds the trampoline hook is preceded
+	 * with an ENDBR instruction.
+	 */
+	if (is_endbr(*(u32 *)ip))
+		ip += ENDBR_INSN_SIZE;
+
+	return __bpf_arch_text_poke(ip, t, old_addr, new_addr);
+}
+
+#define EMIT_LFENCE()	EMIT3(0x0F, 0xAE, 0xE8)
+
+static void emit_indirect_jump(u8 **pprog, int reg, u8 *ip)
+{
+	u8 *prog = *pprog;
+
+	if (cpu_feature_enabled(X86_FEATURE_RETPOLINE_LFENCE)) {
+		EMIT_LFENCE();
+		EMIT2(0xFF, 0xE0 + reg);
+	} else if (cpu_feature_enabled(X86_FEATURE_RETPOLINE)) {
+		OPTIMIZER_HIDE_VAR(reg);
+		emit_jump(&prog, &__x86_indirect_thunk_array[reg], ip);
+	} else {
+		EMIT2(0xFF, 0xE0 + reg);	/* jmp *%\reg */
+		if (IS_ENABLED(CONFIG_RETPOLINE) || IS_ENABLED(CONFIG_SLS))
+			EMIT1(0xCC);		/* int3 */
+	}
+
+	*pprog = prog;
+}
+
+static void emit_return(u8 **pprog, u8 *ip)
+{
+	u8 *prog = *pprog;
+
+	if (cpu_feature_enabled(X86_FEATURE_RETHUNK)) {
+		emit_jump(&prog, &__x86_return_thunk, ip);
+	} else {
+		EMIT1(0xC3);		/* ret */
+		if (IS_ENABLED(CONFIG_SLS))
+			EMIT1(0xCC);	/* int3 */
+	}
+
+	*pprog = prog;
+}
+
+/*
+ * Generate the following code:
+ *
+ * ... bpf_tail_call(void *ctx, struct bpf_array *array, u64 index) ...
+ *   if (index >= array->map.max_entries)
+ *     goto out;
+ *   if (tail_call_cnt++ >= MAX_TAIL_CALL_CNT)
+ *     goto out;
+ *   prog = array->ptrs[index];
+ *   if (prog == NULL)
+ *     goto out;
+ *   goto *(prog->bpf_func + prologue_size);
+ * out:
+ */
+static void emit_bpf_tail_call_indirect(u8 **pprog, bool *callee_regs_used,
+					u32 stack_depth, u8 *ip,
+					struct jit_context *ctx)
+{
+	int tcc_off = -4 - round_up(stack_depth, 8);
+	u8 *prog = *pprog, *start = *pprog;
+	int offset;
+
+	/*
+	 * rdi - pointer to ctx
+	 * rsi - pointer to bpf_array
+	 * rdx - index in bpf_array
+	 */
+
+	/*
+	 * if (index >= array->map.max_entries)
+	 *	goto out;
+	 */
+	EMIT2(0x89, 0xD2);                        /* mov edx, edx */
+	EMIT3(0x39, 0x56,                         /* cmp dword ptr [rsi + 16], edx */
+	      offsetof(struct bpf_array, map.max_entries));
+
+	offset = ctx->tail_call_indirect_label - (prog + 2 - start);
+	EMIT2(X86_JBE, offset);                   /* jbe out */
+
+	/*
+	 * if (tail_call_cnt++ >= MAX_TAIL_CALL_CNT)
+	 *	goto out;
+	 */
+	EMIT2_off32(0x8B, 0x85, tcc_off);         /* mov eax, dword ptr [rbp - tcc_off] */
+	EMIT3(0x83, 0xF8, MAX_TAIL_CALL_CNT);     /* cmp eax, MAX_TAIL_CALL_CNT */
+
+	offset = ctx->tail_call_indirect_label - (prog + 2 - start);
+	EMIT2(X86_JAE, offset);                   /* jae out */
+	EMIT3(0x83, 0xC0, 0x01);                  /* add eax, 1 */
+	EMIT2_off32(0x89, 0x85, tcc_off);         /* mov dword ptr [rbp - tcc_off], eax */
+
+	/* prog = array->ptrs[index]; */
+	EMIT4_off32(0x48, 0x8B, 0x8C, 0xD6,       /* mov rcx, [rsi + rdx * 8 + offsetof(...)] */
+		    offsetof(struct bpf_array, ptrs));
+
+	/*
+	 * if (prog == NULL)
+	 *	goto out;
+	 */
+	EMIT3(0x48, 0x85, 0xC9);                  /* test rcx,rcx */
+
+	offset = ctx->tail_call_indirect_label - (prog + 2 - start);
+	EMIT2(X86_JE, offset);                    /* je out */
+
+	pop_callee_regs(&prog, callee_regs_used);
+
+	EMIT1(0x58);                              /* pop rax */
+	if (stack_depth)
+		EMIT3_off32(0x48, 0x81, 0xC4,     /* add rsp, sd */
+			    round_up(stack_depth, 8));
+
+	/* goto *(prog->bpf_func + X86_TAIL_CALL_OFFSET); */
+	EMIT4(0x48, 0x8B, 0x49,                   /* mov rcx, qword ptr [rcx + 32] */
+	      offsetof(struct bpf_prog, bpf_func));
+	EMIT4(0x48, 0x83, 0xC1,                   /* add rcx, X86_TAIL_CALL_OFFSET */
+	      X86_TAIL_CALL_OFFSET);
+	/*
+	 * Now we're ready to jump into next BPF program
+	 * rdi == ctx (1st arg)
+	 * rcx == prog->bpf_func + X86_TAIL_CALL_OFFSET
+	 */
+	emit_indirect_jump(&prog, 1 /* rcx */, ip + (prog - start));
+
+	/* out: */
+	ctx->tail_call_indirect_label = prog - start;
+	*pprog = prog;
+}
+
+static void emit_bpf_tail_call_direct(struct bpf_jit_poke_descriptor *poke,
+				      u8 **pprog, u8 *ip,
+				      bool *callee_regs_used, u32 stack_depth,
+				      struct jit_context *ctx)
+{
+	int tcc_off = -4 - round_up(stack_depth, 8);
+	u8 *prog = *pprog, *start = *pprog;
+	int offset;
+
+	/*
+	 * if (tail_call_cnt++ >= MAX_TAIL_CALL_CNT)
+	 *	goto out;
+	 */
+	EMIT2_off32(0x8B, 0x85, tcc_off);             /* mov eax, dword ptr [rbp - tcc_off] */
+	EMIT3(0x83, 0xF8, MAX_TAIL_CALL_CNT);         /* cmp eax, MAX_TAIL_CALL_CNT */
+
+	offset = ctx->tail_call_direct_label - (prog + 2 - start);
+	EMIT2(X86_JAE, offset);                       /* jae out */
+	EMIT3(0x83, 0xC0, 0x01);                      /* add eax, 1 */
+	EMIT2_off32(0x89, 0x85, tcc_off);             /* mov dword ptr [rbp - tcc_off], eax */
+
+	poke->tailcall_bypass = ip + (prog - start);
+	poke->adj_off = X86_TAIL_CALL_OFFSET;
+	poke->tailcall_target = ip + ctx->tail_call_direct_label - X86_PATCH_SIZE;
+	poke->bypass_addr = (u8 *)poke->tailcall_target + X86_PATCH_SIZE;
+
+	emit_jump(&prog, (u8 *)poke->tailcall_target + X86_PATCH_SIZE,
+		  poke->tailcall_bypass);
+
+	pop_callee_regs(&prog, callee_regs_used);
+	EMIT1(0x58);                                  /* pop rax */
+	if (stack_depth)
+		EMIT3_off32(0x48, 0x81, 0xC4, round_up(stack_depth, 8));
+
+	memcpy(prog, x86_nops[5], X86_PATCH_SIZE);
+	prog += X86_PATCH_SIZE;
+
+	/* out: */
+	ctx->tail_call_direct_label = prog - start;
+
+	*pprog = prog;
+}
+
+static void bpf_tail_call_direct_fixup(struct bpf_prog *prog)
+{
+	struct bpf_jit_poke_descriptor *poke;
+	struct bpf_array *array;
+	struct bpf_prog *target;
+	int i, ret;
+
+	for (i = 0; i < prog->aux->size_poke_tab; i++) {
+		poke = &prog->aux->poke_tab[i];
+		if (poke->aux && poke->aux != prog->aux)
+			continue;
+
+		WARN_ON_ONCE(READ_ONCE(poke->tailcall_target_stable));
+
+		if (poke->reason != BPF_POKE_REASON_TAIL_CALL)
+			continue;
+
+		array = container_of(poke->tail_call.map, struct bpf_array, map);
+		mutex_lock(&array->aux->poke_mutex);
+		target = array->ptrs[poke->tail_call.key];
+		if (target) {
+			ret = __bpf_arch_text_poke(poke->tailcall_target,
+						   BPF_MOD_JUMP, NULL,
+						   (u8 *)target->bpf_func +
+						   poke->adj_off);
+			BUG_ON(ret < 0);
+			ret = __bpf_arch_text_poke(poke->tailcall_bypass,
+						   BPF_MOD_JUMP,
+						   (u8 *)poke->tailcall_target +
+						   X86_PATCH_SIZE, NULL);
+			BUG_ON(ret < 0);
+		}
+		WRITE_ONCE(poke->tailcall_target_stable, true);
+		mutex_unlock(&array->aux->poke_mutex);
+	}
+}
+
+static void emit_mov_imm32(u8 **pprog, bool sign_propagate,
+			   u32 dst_reg, const u32 imm32)
+{
+	u8 *prog = *pprog;
+	u8 b1, b2, b3;
+
+	/*
+	 * Optimization: if imm32 is positive, use 'mov %eax, imm32'
+	 * (which zero-extends imm32) to save 2 bytes.
+	 */
+	if (sign_propagate && (s32)imm32 < 0) {
+		/* 'mov %rax, imm32' sign extends imm32 */
+		b1 = add_1mod(0x48, dst_reg);
+		b2 = 0xC7;
+		b3 = 0xC0;
+		EMIT3_off32(b1, b2, add_1reg(b3, dst_reg), imm32);
+		goto done;
+	}
+
+	/*
+	 * Optimization: if imm32 is zero, use 'xor %eax, %eax'
+	 * to save 3 bytes.
+	 */
+	if (imm32 == 0) {
+		if (is_ereg(dst_reg))
+			EMIT1(add_2mod(0x40, dst_reg, dst_reg));
+		b2 = 0x31; /* xor */
+		b3 = 0xC0;
+		EMIT2(b2, add_2reg(b3, dst_reg, dst_reg));
+		goto done;
+	}
+
+	/* mov %eax, imm32 */
+	if (is_ereg(dst_reg))
+		EMIT1(add_1mod(0x40, dst_reg));
+	EMIT1_off32(add_1reg(0xB8, dst_reg), imm32);
+done:
+	*pprog = prog;
+}
+
+static void emit_mov_imm64(u8 **pprog, u32 dst_reg,
+			   const u32 imm32_hi, const u32 imm32_lo)
+{
+	u8 *prog = *pprog;
+
+	if (is_uimm32(((u64)imm32_hi << 32) | (u32)imm32_lo)) {
+		/*
+		 * For emitting plain u32, where sign bit must not be
+		 * propagated LLVM tends to load imm64 over mov32
+		 * directly, so save couple of bytes by just doing
+		 * 'mov %eax, imm32' instead.
+		 */
+		emit_mov_imm32(&prog, false, dst_reg, imm32_lo);
+	} else {
+		/* movabsq rax, imm64 */
+		EMIT2(add_1mod(0x48, dst_reg), add_1reg(0xB8, dst_reg));
+		EMIT(imm32_lo, 4);
+		EMIT(imm32_hi, 4);
+	}
+
+	*pprog = prog;
+}
+
+static void emit_mov_reg(u8 **pprog, bool is64, u32 dst_reg, u32 src_reg)
+{
+	u8 *prog = *pprog;
+
+	if (is64) {
+		/* mov dst, src */
+		EMIT_mov(dst_reg, src_reg);
+	} else {
+		/* mov32 dst, src */
+		if (is_ereg(dst_reg) || is_ereg(src_reg))
+			EMIT1(add_2mod(0x40, dst_reg, src_reg));
+		EMIT2(0x89, add_2reg(0xC0, dst_reg, 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;
+
+	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;
+
+	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;
+}
+
+/*
+ * Similar version of maybe_emit_mod() for a single register
+ */
+static void maybe_emit_1mod(u8 **pprog, u32 reg, bool is64)
+{
+	u8 *prog = *pprog;
+
+	if (is64)
+		EMIT1(add_1mod(0x48, reg));
+	else if (is_ereg(reg))
+		EMIT1(add_1mod(0x40, 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)
+{
+	u8 *prog = *pprog;
+
+	switch (size) {
+	case BPF_B:
+		/* Emit 'movzx rax, byte ptr [rax + off]' */
+		EMIT3(add_2mod(0x48, src_reg, dst_reg), 0x0F, 0xB6);
+		break;
+	case BPF_H:
+		/* Emit 'movzx rax, word ptr [rax + off]' */
+		EMIT3(add_2mod(0x48, src_reg, dst_reg), 0x0F, 0xB7);
+		break;
+	case BPF_W:
+		/* Emit 'mov eax, dword ptr [rax+0x14]' */
+		if (is_ereg(dst_reg) || is_ereg(src_reg))
+			EMIT2(add_2mod(0x40, src_reg, dst_reg), 0x8B);
+		else
+			EMIT1(0x8B);
+		break;
+	case BPF_DW:
+		/* Emit 'mov rax, qword ptr [rax+0x14]' */
+		EMIT2(add_2mod(0x48, src_reg, dst_reg), 0x8B);
+		break;
+	}
+	emit_insn_suffix(&prog, src_reg, dst_reg, off);
+	*pprog = prog;
+}
+
+/* STX: *(u8*)(dst_reg + off) = src_reg */
+static void emit_stx(u8 **pprog, u32 size, u32 dst_reg, u32 src_reg, int off)
+{
+	u8 *prog = *pprog;
+
+	switch (size) {
+	case BPF_B:
+		/* Emit 'mov byte ptr [rax + off], al' */
+		if (is_ereg(dst_reg) || is_ereg_8l(src_reg))
+			/* Add extra byte for eregs or SIL,DIL,BPL in src_reg */
+			EMIT2(add_2mod(0x40, dst_reg, src_reg), 0x88);
+		else
+			EMIT1(0x88);
+		break;
+	case BPF_H:
+		if (is_ereg(dst_reg) || is_ereg(src_reg))
+			EMIT3(0x66, add_2mod(0x40, dst_reg, src_reg), 0x89);
+		else
+			EMIT2(0x66, 0x89);
+		break;
+	case BPF_W:
+		if (is_ereg(dst_reg) || is_ereg(src_reg))
+			EMIT2(add_2mod(0x40, dst_reg, src_reg), 0x89);
+		else
+			EMIT1(0x89);
+		break;
+	case BPF_DW:
+		EMIT2(add_2mod(0x48, dst_reg, src_reg), 0x89);
+		break;
+	}
+	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;
+
+	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_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)
+{
+	u32 reg = x->fixup >> 8;
+
+	/* jump over faulting load and clear dest register */
+	*(unsigned long *)((void *)regs + reg) = 0;
+	regs->ip += x->fixup & 0xff;
+	return true;
+}
+
+static void detect_reg_usage(struct bpf_insn *insn, int insn_cnt,
+			     bool *regs_used, bool *tail_call_seen)
+{
+	int i;
+
+	for (i = 1; i <= insn_cnt; i++, insn++) {
+		if (insn->code == (BPF_JMP | BPF_TAIL_CALL))
+			*tail_call_seen = true;
+		if (insn->dst_reg == BPF_REG_6 || insn->src_reg == BPF_REG_6)
+			regs_used[0] = true;
+		if (insn->dst_reg == BPF_REG_7 || insn->src_reg == BPF_REG_7)
+			regs_used[1] = true;
+		if (insn->dst_reg == BPF_REG_8 || insn->src_reg == BPF_REG_8)
+			regs_used[2] = true;
+		if (insn->dst_reg == BPF_REG_9 || insn->src_reg == BPF_REG_9)
+			regs_used[3] = true;
+	}
+}
+
+static void emit_nops(u8 **pprog, int len)
+{
+	u8 *prog = *pprog;
+	int i, noplen;
+
+	while (len > 0) {
+		noplen = len;
+
+		if (noplen > ASM_NOP_MAX)
+			noplen = ASM_NOP_MAX;
+
+		for (i = 0; i < noplen; i++)
+			EMIT1(x86_nops[noplen][i]);
+		len -= noplen;
+	}
+
+	*pprog = prog;
+}
+
+#define INSN_SZ_DIFF (((addrs[i] - addrs[i - 1]) - (prog - temp)))
+
+/* mov rax, qword ptr [rbp - rounded_stack_depth - 8] */
+#define RESTORE_TAIL_CALL_CNT(stack)				\
+	EMIT3_off32(0x48, 0x8B, 0x85, -round_up(stack, 8) - 8)
+
+static int do_jit(struct bpf_prog *bpf_prog, int *addrs, u8 *image, u8 *rw_image,
+		  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;
+	bool callee_regs_used[4] = {};
+	int insn_cnt = bpf_prog->len;
+	bool tail_call_seen = false;
+	bool seen_exit = false;
+	u8 temp[BPF_MAX_INSN_SIZE + BPF_INSN_SAFETY];
+	int i, excnt = 0;
+	int ilen, proglen = 0;
+	u8 *prog = temp;
+	int err;
+
+	detect_reg_usage(insn, insn_cnt, callee_regs_used,
+			 &tail_call_seen);
+
+	/* tail call's presence in current prog implies it is reachable */
+	tail_call_reachable |= tail_call_seen;
+
+	emit_prologue(&prog, bpf_prog->aux->stack_depth,
+		      bpf_prog_was_classic(bpf_prog), tail_call_reachable,
+		      bpf_prog->aux->func_idx != 0);
+	push_callee_regs(&prog, callee_regs_used);
+
+	ilen = prog - temp;
+	if (rw_image)
+		memcpy(rw_image + proglen, temp, ilen);
+	proglen += ilen;
+	addrs[0] = proglen;
+	prog = temp;
+
+	for (i = 1; i <= insn_cnt; i++, insn++) {
+		const s32 imm32 = insn->imm;
+		u32 dst_reg = insn->dst_reg;
+		u32 src_reg = insn->src_reg;
+		u8 b2 = 0, b3 = 0;
+		u8 *start_of_ldx;
+		s64 jmp_offset;
+		u8 jmp_cond;
+		u8 *func;
+		int nops;
+
+		switch (insn->code) {
+			/* ALU */
+		case BPF_ALU | BPF_ADD | BPF_X:
+		case BPF_ALU | BPF_SUB | BPF_X:
+		case BPF_ALU | BPF_AND | BPF_X:
+		case BPF_ALU | BPF_OR | BPF_X:
+		case BPF_ALU | BPF_XOR | BPF_X:
+		case BPF_ALU64 | BPF_ADD | BPF_X:
+		case BPF_ALU64 | BPF_SUB | BPF_X:
+		case BPF_ALU64 | BPF_AND | BPF_X:
+		case BPF_ALU64 | BPF_OR | BPF_X:
+		case BPF_ALU64 | BPF_XOR | BPF_X:
+			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;
+
+		case BPF_ALU64 | BPF_MOV | BPF_X:
+		case BPF_ALU | BPF_MOV | BPF_X:
+			emit_mov_reg(&prog,
+				     BPF_CLASS(insn->code) == BPF_ALU64,
+				     dst_reg, src_reg);
+			break;
+
+			/* neg dst */
+		case BPF_ALU | BPF_NEG:
+		case BPF_ALU64 | BPF_NEG:
+			maybe_emit_1mod(&prog, dst_reg,
+					BPF_CLASS(insn->code) == BPF_ALU64);
+			EMIT2(0xF7, add_1reg(0xD8, dst_reg));
+			break;
+
+		case BPF_ALU | BPF_ADD | BPF_K:
+		case BPF_ALU | BPF_SUB | BPF_K:
+		case BPF_ALU | BPF_AND | BPF_K:
+		case BPF_ALU | BPF_OR | BPF_K:
+		case BPF_ALU | BPF_XOR | BPF_K:
+		case BPF_ALU64 | BPF_ADD | BPF_K:
+		case BPF_ALU64 | BPF_SUB | BPF_K:
+		case BPF_ALU64 | BPF_AND | BPF_K:
+		case BPF_ALU64 | BPF_OR | BPF_K:
+		case BPF_ALU64 | BPF_XOR | BPF_K:
+			maybe_emit_1mod(&prog, dst_reg,
+					BPF_CLASS(insn->code) == BPF_ALU64);
+
+			/*
+			 * b3 holds 'normal' opcode, b2 short form only valid
+			 * in case dst is eax/rax.
+			 */
+			switch (BPF_OP(insn->code)) {
+			case BPF_ADD:
+				b3 = 0xC0;
+				b2 = 0x05;
+				break;
+			case BPF_SUB:
+				b3 = 0xE8;
+				b2 = 0x2D;
+				break;
+			case BPF_AND:
+				b3 = 0xE0;
+				b2 = 0x25;
+				break;
+			case BPF_OR:
+				b3 = 0xC8;
+				b2 = 0x0D;
+				break;
+			case BPF_XOR:
+				b3 = 0xF0;
+				b2 = 0x35;
+				break;
+			}
+
+			if (is_imm8(imm32))
+				EMIT3(0x83, add_1reg(b3, dst_reg), imm32);
+			else if (is_axreg(dst_reg))
+				EMIT1_off32(b2, imm32);
+			else
+				EMIT2_off32(0x81, add_1reg(b3, dst_reg), imm32);
+			break;
+
+		case BPF_ALU64 | BPF_MOV | BPF_K:
+		case BPF_ALU | BPF_MOV | BPF_K:
+			emit_mov_imm32(&prog, BPF_CLASS(insn->code) == BPF_ALU64,
+				       dst_reg, imm32);
+			break;
+
+		case BPF_LD | BPF_IMM | BPF_DW:
+			emit_mov_imm64(&prog, dst_reg, insn[1].imm, insn[0].imm);
+			insn++;
+			i++;
+			break;
+
+			/* dst %= src, dst /= src, dst %= imm32, dst /= imm32 */
+		case BPF_ALU | BPF_MOD | BPF_X:
+		case BPF_ALU | BPF_DIV | BPF_X:
+		case BPF_ALU | BPF_MOD | BPF_K:
+		case BPF_ALU | BPF_DIV | BPF_K:
+		case BPF_ALU64 | BPF_MOD | BPF_X:
+		case BPF_ALU64 | BPF_DIV | BPF_X:
+		case BPF_ALU64 | BPF_MOD | BPF_K:
+		case BPF_ALU64 | BPF_DIV | BPF_K: {
+			bool is64 = BPF_CLASS(insn->code) == BPF_ALU64;
+
+			if (dst_reg != BPF_REG_0)
+				EMIT1(0x50); /* push rax */
+			if (dst_reg != BPF_REG_3)
+				EMIT1(0x52); /* push rdx */
+
+			if (BPF_SRC(insn->code) == BPF_X) {
+				if (src_reg == BPF_REG_0 ||
+				    src_reg == BPF_REG_3) {
+					/* mov r11, src_reg */
+					EMIT_mov(AUX_REG, src_reg);
+					src_reg = AUX_REG;
+				}
+			} else {
+				/* mov r11, imm32 */
+				EMIT3_off32(0x49, 0xC7, 0xC3, imm32);
+				src_reg = AUX_REG;
+			}
+
+			if (dst_reg != BPF_REG_0)
+				/* mov rax, dst_reg */
+				emit_mov_reg(&prog, is64, BPF_REG_0, dst_reg);
+
+			/*
+			 * xor edx, edx
+			 * equivalent to 'xor rdx, rdx', but one byte less
+			 */
+			EMIT2(0x31, 0xd2);
+
+			/* div src_reg */
+			maybe_emit_1mod(&prog, src_reg, is64);
+			EMIT2(0xF7, add_1reg(0xF0, src_reg));
+
+			if (BPF_OP(insn->code) == BPF_MOD &&
+			    dst_reg != BPF_REG_3)
+				/* mov dst_reg, rdx */
+				emit_mov_reg(&prog, is64, dst_reg, BPF_REG_3);
+			else if (BPF_OP(insn->code) == BPF_DIV &&
+				 dst_reg != BPF_REG_0)
+				/* mov dst_reg, rax */
+				emit_mov_reg(&prog, is64, dst_reg, BPF_REG_0);
+
+			if (dst_reg != BPF_REG_3)
+				EMIT1(0x5A); /* pop rdx */
+			if (dst_reg != BPF_REG_0)
+				EMIT1(0x58); /* pop rax */
+			break;
+		}
+
+		case BPF_ALU | BPF_MUL | BPF_K:
+		case BPF_ALU64 | BPF_MUL | BPF_K:
+			maybe_emit_mod(&prog, dst_reg, dst_reg,
+				       BPF_CLASS(insn->code) == BPF_ALU64);
+
+			if (is_imm8(imm32))
+				/* imul dst_reg, dst_reg, imm8 */
+				EMIT3(0x6B, add_2reg(0xC0, dst_reg, dst_reg),
+				      imm32);
+			else
+				/* imul dst_reg, dst_reg, imm32 */
+				EMIT2_off32(0x69,
+					    add_2reg(0xC0, dst_reg, dst_reg),
+					    imm32);
+			break;
+
+		case BPF_ALU | BPF_MUL | BPF_X:
+		case BPF_ALU64 | BPF_MUL | BPF_X:
+			maybe_emit_mod(&prog, src_reg, dst_reg,
+				       BPF_CLASS(insn->code) == BPF_ALU64);
+
+			/* imul dst_reg, src_reg */
+			EMIT3(0x0F, 0xAF, add_2reg(0xC0, src_reg, dst_reg));
+			break;
+
+			/* Shifts */
+		case BPF_ALU | BPF_LSH | BPF_K:
+		case BPF_ALU | BPF_RSH | BPF_K:
+		case BPF_ALU | BPF_ARSH | BPF_K:
+		case BPF_ALU64 | BPF_LSH | BPF_K:
+		case BPF_ALU64 | BPF_RSH | BPF_K:
+		case BPF_ALU64 | BPF_ARSH | BPF_K:
+			maybe_emit_1mod(&prog, dst_reg,
+					BPF_CLASS(insn->code) == BPF_ALU64);
+
+			b3 = simple_alu_opcodes[BPF_OP(insn->code)];
+			if (imm32 == 1)
+				EMIT2(0xD1, add_1reg(b3, dst_reg));
+			else
+				EMIT3(0xC1, add_1reg(b3, dst_reg), imm32);
+			break;
+
+		case BPF_ALU | BPF_LSH | BPF_X:
+		case BPF_ALU | BPF_RSH | BPF_X:
+		case BPF_ALU | BPF_ARSH | BPF_X:
+		case BPF_ALU64 | BPF_LSH | BPF_X:
+		case BPF_ALU64 | BPF_RSH | BPF_X:
+		case BPF_ALU64 | BPF_ARSH | BPF_X:
+
+			/* Check for bad case when dst_reg == rcx */
+			if (dst_reg == BPF_REG_4) {
+				/* mov r11, dst_reg */
+				EMIT_mov(AUX_REG, dst_reg);
+				dst_reg = AUX_REG;
+			}
+
+			if (src_reg != BPF_REG_4) { /* common case */
+				EMIT1(0x51); /* push rcx */
+
+				/* mov rcx, src_reg */
+				EMIT_mov(BPF_REG_4, src_reg);
+			}
+
+			/* shl %rax, %cl | shr %rax, %cl | sar %rax, %cl */
+			maybe_emit_1mod(&prog, dst_reg,
+					BPF_CLASS(insn->code) == BPF_ALU64);
+
+			b3 = simple_alu_opcodes[BPF_OP(insn->code)];
+			EMIT2(0xD3, add_1reg(b3, dst_reg));
+
+			if (src_reg != BPF_REG_4)
+				EMIT1(0x59); /* pop rcx */
+
+			if (insn->dst_reg == BPF_REG_4)
+				/* mov dst_reg, r11 */
+				EMIT_mov(insn->dst_reg, AUX_REG);
+			break;
+
+		case BPF_ALU | BPF_END | BPF_FROM_BE:
+			switch (imm32) {
+			case 16:
+				/* Emit 'ror %ax, 8' to swap lower 2 bytes */
+				EMIT1(0x66);
+				if (is_ereg(dst_reg))
+					EMIT1(0x41);
+				EMIT3(0xC1, add_1reg(0xC8, dst_reg), 8);
+
+				/* Emit 'movzwl eax, ax' */
+				if (is_ereg(dst_reg))
+					EMIT3(0x45, 0x0F, 0xB7);
+				else
+					EMIT2(0x0F, 0xB7);
+				EMIT1(add_2reg(0xC0, dst_reg, dst_reg));
+				break;
+			case 32:
+				/* Emit 'bswap eax' to swap lower 4 bytes */
+				if (is_ereg(dst_reg))
+					EMIT2(0x41, 0x0F);
+				else
+					EMIT1(0x0F);
+				EMIT1(add_1reg(0xC8, dst_reg));
+				break;
+			case 64:
+				/* Emit 'bswap rax' to swap 8 bytes */
+				EMIT3(add_1mod(0x48, dst_reg), 0x0F,
+				      add_1reg(0xC8, dst_reg));
+				break;
+			}
+			break;
+
+		case BPF_ALU | BPF_END | BPF_FROM_LE:
+			switch (imm32) {
+			case 16:
+				/*
+				 * Emit 'movzwl eax, ax' to zero extend 16-bit
+				 * into 64 bit
+				 */
+				if (is_ereg(dst_reg))
+					EMIT3(0x45, 0x0F, 0xB7);
+				else
+					EMIT2(0x0F, 0xB7);
+				EMIT1(add_2reg(0xC0, dst_reg, dst_reg));
+				break;
+			case 32:
+				/* Emit 'mov eax, eax' to clear upper 32-bits */
+				if (is_ereg(dst_reg))
+					EMIT1(0x45);
+				EMIT2(0x89, add_2reg(0xC0, dst_reg, dst_reg));
+				break;
+			case 64:
+				/* nop */
+				break;
+			}
+			break;
+
+			/* speculation barrier */
+		case BPF_ST | BPF_NOSPEC:
+			if (boot_cpu_has(X86_FEATURE_XMM2))
+				EMIT_LFENCE();
+			break;
+
+			/* ST: *(u8*)(dst_reg + off) = imm */
+		case BPF_ST | BPF_MEM | BPF_B:
+			if (is_ereg(dst_reg))
+				EMIT2(0x41, 0xC6);
+			else
+				EMIT1(0xC6);
+			goto st;
+		case BPF_ST | BPF_MEM | BPF_H:
+			if (is_ereg(dst_reg))
+				EMIT3(0x66, 0x41, 0xC7);
+			else
+				EMIT2(0x66, 0xC7);
+			goto st;
+		case BPF_ST | BPF_MEM | BPF_W:
+			if (is_ereg(dst_reg))
+				EMIT2(0x41, 0xC7);
+			else
+				EMIT1(0xC7);
+			goto st;
+		case BPF_ST | BPF_MEM | BPF_DW:
+			EMIT2(add_1mod(0x48, dst_reg), 0xC7);
+
+st:			if (is_imm8(insn->off))
+				EMIT2(add_1reg(0x40, dst_reg), insn->off);
+			else
+				EMIT1_off32(add_1reg(0x80, dst_reg), insn->off);
+
+			EMIT(imm32, bpf_size_to_x86_bytes(BPF_SIZE(insn->code)));
+			break;
+
+			/* STX: *(u8*)(dst_reg + off) = src_reg */
+		case BPF_STX | BPF_MEM | BPF_B:
+		case BPF_STX | BPF_MEM | BPF_H:
+		case BPF_STX | BPF_MEM | BPF_W:
+		case BPF_STX | BPF_MEM | BPF_DW:
+			emit_stx(&prog, BPF_SIZE(insn->code), dst_reg, src_reg, insn->off);
+			break;
+
+			/* LDX: dst_reg = *(u8*)(src_reg + off) */
+		case BPF_LDX | BPF_MEM | BPF_B:
+		case BPF_LDX | BPF_PROBE_MEM | BPF_B:
+		case BPF_LDX | BPF_MEM | BPF_H:
+		case BPF_LDX | BPF_PROBE_MEM | BPF_H:
+		case BPF_LDX | BPF_MEM | BPF_W:
+		case BPF_LDX | BPF_PROBE_MEM | BPF_W:
+		case BPF_LDX | BPF_MEM | BPF_DW:
+		case BPF_LDX | BPF_PROBE_MEM | BPF_DW:
+			if (BPF_MODE(insn->code) == BPF_PROBE_MEM) {
+				/* Though the verifier prevents negative insn->off in BPF_PROBE_MEM
+				 * add abs(insn->off) to the limit to make sure that negative
+				 * offset won't be an issue.
+				 * insn->off is s16, so it won't affect valid pointers.
+				 */
+				u64 limit = TASK_SIZE_MAX + PAGE_SIZE + abs(insn->off);
+				u8 *end_of_jmp1, *end_of_jmp2;
+
+				/* Conservatively check that src_reg + insn->off is a kernel address:
+				 * 1. src_reg + insn->off >= limit
+				 * 2. src_reg + insn->off doesn't become small positive.
+				 * Cannot do src_reg + insn->off >= limit in one branch,
+				 * since it needs two spare registers, but JIT has only one.
+				 */
+
+				/* movabsq r11, limit */
+				EMIT2(add_1mod(0x48, AUX_REG), add_1reg(0xB8, AUX_REG));
+				EMIT((u32)limit, 4);
+				EMIT(limit >> 32, 4);
+				/* cmp src_reg, r11 */
+				maybe_emit_mod(&prog, src_reg, AUX_REG, true);
+				EMIT2(0x39, add_2reg(0xC0, src_reg, AUX_REG));
+				/* if unsigned '<' goto end_of_jmp2 */
+				EMIT2(X86_JB, 0);
+				end_of_jmp1 = prog;
+
+				/* mov r11, src_reg */
+				emit_mov_reg(&prog, true, AUX_REG, src_reg);
+				/* add r11, insn->off */
+				maybe_emit_1mod(&prog, AUX_REG, true);
+				EMIT2_off32(0x81, add_1reg(0xC0, AUX_REG), insn->off);
+				/* jmp if not carry to start_of_ldx
+				 * Otherwise ERR_PTR(-EINVAL) + 128 will be the user addr
+				 * that has to be rejected.
+				 */
+				EMIT2(0x73 /* JNC */, 0);
+				end_of_jmp2 = prog;
+
+				/* xor dst_reg, dst_reg */
+				emit_mov_imm32(&prog, false, dst_reg, 0);
+				/* jmp byte_after_ldx */
+				EMIT2(0xEB, 0);
+
+				/* populate jmp_offset for JB above to jump to xor dst_reg */
+				end_of_jmp1[-1] = end_of_jmp2 - end_of_jmp1;
+				/* populate jmp_offset for JNC above to jump to start_of_ldx */
+				start_of_ldx = prog;
+				end_of_jmp2[-1] = start_of_ldx - end_of_jmp2;
+			}
+			emit_ldx(&prog, BPF_SIZE(insn->code), dst_reg, src_reg, insn->off);
+			if (BPF_MODE(insn->code) == BPF_PROBE_MEM) {
+				struct exception_table_entry *ex;
+				u8 *_insn = image + proglen + (start_of_ldx - temp);
+				s64 delta;
+
+				/* populate jmp_offset for JMP above */
+				start_of_ldx[-1] = prog - start_of_ldx;
+
+				if (!bpf_prog->aux->extable)
+					break;
+
+				if (excnt >= bpf_prog->aux->num_exentries) {
+					pr_err("ex gen bug\n");
+					return -EFAULT;
+				}
+				ex = &bpf_prog->aux->extable[excnt++];
+
+				delta = _insn - (u8 *)&ex->insn;
+				if (!is_simm32(delta)) {
+					pr_err("extable->insn doesn't fit into 32-bit\n");
+					return -EFAULT;
+				}
+				/* switch ex to rw buffer for writes */
+				ex = (void *)rw_image + ((void *)ex - (void *)image);
+
+				ex->insn = delta;
+
+				ex->data = EX_TYPE_BPF;
+
+				if (dst_reg > BPF_REG_9) {
+					pr_err("verifier error\n");
+					return -EFAULT;
+				}
+				/*
+				 * Compute size of x86 insn and its target dest x86 register.
+				 * ex_handler_bpf() will use lower 8 bits to adjust
+				 * pt_regs->ip to jump over this x86 instruction
+				 * and upper bits to figure out which pt_regs to zero out.
+				 * End result: x86 insn "mov rbx, qword ptr [rax+0x14]"
+				 * of 4 bytes will be ignored and rbx will be zero inited.
+				 */
+				ex->fixup = (prog - start_of_ldx) | (reg2pt_regs[dst_reg] << 8);
+			}
+			break;
+
+		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)) {
+				bool is64 = BPF_SIZE(insn->code) == BPF_DW;
+				u32 real_src_reg = src_reg;
+				u32 real_dst_reg = dst_reg;
+				u8 *branch_target;
+
+				/*
+				 * 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);
+				if (src_reg == BPF_REG_0)
+					real_src_reg = BPF_REG_AX;
+				if (dst_reg == BPF_REG_0)
+					real_dst_reg = BPF_REG_AX;
+
+				branch_target = prog;
+				/* Load old value */
+				emit_ldx(&prog, BPF_SIZE(insn->code),
+					 BPF_REG_0, real_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, real_src_reg, is64);
+				EMIT2(simple_alu_opcodes[BPF_OP(insn->imm)],
+				      add_2reg(0xC0, AUX_REG, real_src_reg));
+				/* Attempt to swap in new value */
+				err = emit_atomic(&prog, BPF_CMPXCHG,
+						  real_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, real_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 */
+		case BPF_JMP | BPF_CALL:
+			func = (u8 *) __bpf_call_base + imm32;
+			if (tail_call_reachable) {
+				RESTORE_TAIL_CALL_CNT(bpf_prog->aux->stack_depth);
+				if (!imm32 || emit_call(&prog, func, image + addrs[i - 1] + 7))
+					return -EINVAL;
+			} else {
+				if (!imm32 || emit_call(&prog, func, image + addrs[i - 1]))
+					return -EINVAL;
+			}
+			break;
+
+		case BPF_JMP | BPF_TAIL_CALL:
+			if (imm32)
+				emit_bpf_tail_call_direct(&bpf_prog->aux->poke_tab[imm32 - 1],
+							  &prog, image + addrs[i - 1],
+							  callee_regs_used,
+							  bpf_prog->aux->stack_depth,
+							  ctx);
+			else
+				emit_bpf_tail_call_indirect(&prog,
+							    callee_regs_used,
+							    bpf_prog->aux->stack_depth,
+							    image + addrs[i - 1],
+							    ctx);
+			break;
+
+			/* cond jump */
+		case BPF_JMP | BPF_JEQ | BPF_X:
+		case BPF_JMP | BPF_JNE | BPF_X:
+		case BPF_JMP | BPF_JGT | BPF_X:
+		case BPF_JMP | BPF_JLT | BPF_X:
+		case BPF_JMP | BPF_JGE | BPF_X:
+		case BPF_JMP | BPF_JLE | BPF_X:
+		case BPF_JMP | BPF_JSGT | BPF_X:
+		case BPF_JMP | BPF_JSLT | BPF_X:
+		case BPF_JMP | BPF_JSGE | BPF_X:
+		case BPF_JMP | BPF_JSLE | BPF_X:
+		case BPF_JMP32 | BPF_JEQ | BPF_X:
+		case BPF_JMP32 | BPF_JNE | BPF_X:
+		case BPF_JMP32 | BPF_JGT | BPF_X:
+		case BPF_JMP32 | BPF_JLT | BPF_X:
+		case BPF_JMP32 | BPF_JGE | BPF_X:
+		case BPF_JMP32 | BPF_JLE | BPF_X:
+		case BPF_JMP32 | BPF_JSGT | BPF_X:
+		case BPF_JMP32 | BPF_JSLT | BPF_X:
+		case BPF_JMP32 | BPF_JSGE | BPF_X:
+		case BPF_JMP32 | BPF_JSLE | BPF_X:
+			/* cmp 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 */
+			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;
+
+		case BPF_JMP | BPF_JSET | BPF_K:
+		case BPF_JMP32 | BPF_JSET | BPF_K:
+			/* test dst_reg, imm32 */
+			maybe_emit_1mod(&prog, dst_reg,
+					BPF_CLASS(insn->code) == BPF_JMP);
+			EMIT2_off32(0xF7, add_1reg(0xC0, dst_reg), imm32);
+			goto emit_cond_jmp;
+
+		case BPF_JMP | BPF_JEQ | BPF_K:
+		case BPF_JMP | BPF_JNE | BPF_K:
+		case BPF_JMP | BPF_JGT | BPF_K:
+		case BPF_JMP | BPF_JLT | BPF_K:
+		case BPF_JMP | BPF_JGE | BPF_K:
+		case BPF_JMP | BPF_JLE | BPF_K:
+		case BPF_JMP | BPF_JSGT | BPF_K:
+		case BPF_JMP | BPF_JSLT | BPF_K:
+		case BPF_JMP | BPF_JSGE | BPF_K:
+		case BPF_JMP | BPF_JSLE | BPF_K:
+		case BPF_JMP32 | BPF_JEQ | BPF_K:
+		case BPF_JMP32 | BPF_JNE | BPF_K:
+		case BPF_JMP32 | BPF_JGT | BPF_K:
+		case BPF_JMP32 | BPF_JLT | BPF_K:
+		case BPF_JMP32 | BPF_JGE | BPF_K:
+		case BPF_JMP32 | BPF_JLE | BPF_K:
+		case BPF_JMP32 | BPF_JSGT | BPF_K:
+		case BPF_JMP32 | BPF_JSLT | BPF_K:
+		case BPF_JMP32 | BPF_JSGE | BPF_K:
+		case BPF_JMP32 | BPF_JSLE | BPF_K:
+			/* test dst_reg, dst_reg to save one extra byte */
+			if (imm32 == 0) {
+				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;
+			}
+
+			/* cmp dst_reg, imm8/32 */
+			maybe_emit_1mod(&prog, dst_reg,
+					BPF_CLASS(insn->code) == BPF_JMP);
+
+			if (is_imm8(imm32))
+				EMIT3(0x83, add_1reg(0xF8, dst_reg), imm32);
+			else
+				EMIT2_off32(0x81, add_1reg(0xF8, dst_reg), imm32);
+
+emit_cond_jmp:		/* Convert BPF opcode to x86 */
+			switch (BPF_OP(insn->code)) {
+			case BPF_JEQ:
+				jmp_cond = X86_JE;
+				break;
+			case BPF_JSET:
+			case BPF_JNE:
+				jmp_cond = X86_JNE;
+				break;
+			case BPF_JGT:
+				/* GT is unsigned '>', JA in x86 */
+				jmp_cond = X86_JA;
+				break;
+			case BPF_JLT:
+				/* LT is unsigned '<', JB in x86 */
+				jmp_cond = X86_JB;
+				break;
+			case BPF_JGE:
+				/* GE is unsigned '>=', JAE in x86 */
+				jmp_cond = X86_JAE;
+				break;
+			case BPF_JLE:
+				/* LE is unsigned '<=', JBE in x86 */
+				jmp_cond = X86_JBE;
+				break;
+			case BPF_JSGT:
+				/* Signed '>', GT in x86 */
+				jmp_cond = X86_JG;
+				break;
+			case BPF_JSLT:
+				/* Signed '<', LT in x86 */
+				jmp_cond = X86_JL;
+				break;
+			case BPF_JSGE:
+				/* Signed '>=', GE in x86 */
+				jmp_cond = X86_JGE;
+				break;
+			case BPF_JSLE:
+				/* Signed '<=', LE in x86 */
+				jmp_cond = X86_JLE;
+				break;
+			default: /* to silence GCC warning */
+				return -EFAULT;
+			}
+			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 subtract 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;
+					}
+					emit_nops(&prog, nops);
+				}
+				EMIT2(jmp_cond, jmp_offset);
+			} else if (is_simm32(jmp_offset)) {
+				EMIT2_off32(0x0F, jmp_cond + 0x10, jmp_offset);
+			} else {
+				pr_err("cond_jmp gen bug %llx\n", jmp_offset);
+				return -EFAULT;
+			}
+
+			break;
+
+		case BPF_JMP | BPF_JA:
+		case BPF_JMP32 | BPF_JA:
+			if (BPF_CLASS(insn->code) == BPF_JMP) {
+				if (insn->off == -1)
+					/* -1 jmp instructions will always jump
+					 * backwards two bytes. Explicitly handling
+					 * this case avoids wasting too many passes
+					 * when there are long sequences of replaced
+					 * dead code.
+					 */
+					jmp_offset = -2;
+				else
+					jmp_offset = addrs[i + insn->off] - addrs[i];
+			} else {
+				if (insn->imm == -1)
+					jmp_offset = -2;
+				else
+					jmp_offset = addrs[i + insn->imm] - addrs[i];
+			}
+
+			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;
+					}
+					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 subtracted 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;
+					}
+					emit_nops(&prog, INSN_SZ_DIFF - 2);
+				}
+				EMIT2(0xEB, jmp_offset);
+			} else if (is_simm32(jmp_offset)) {
+				EMIT1_off32(0xE9, jmp_offset);
+			} else {
+				pr_err("jmp gen bug %llx\n", jmp_offset);
+				return -EFAULT;
+			}
+			break;
+
+		case BPF_JMP | BPF_EXIT:
+			if (seen_exit) {
+				jmp_offset = ctx->cleanup_addr - addrs[i];
+				goto emit_jmp;
+			}
+			seen_exit = true;
+			/* Update cleanup_addr */
+			ctx->cleanup_addr = proglen;
+			pop_callee_regs(&prog, callee_regs_used);
+			EMIT1(0xC9);         /* leave */
+			emit_return(&prog, image + addrs[i - 1] + (prog - temp));
+			break;
+
+		default:
+			/*
+			 * By design x86-64 JIT should support all BPF instructions.
+			 * This error will be seen if new instruction was added
+			 * to the interpreter, but not to the JIT, or if there is
+			 * junk in bpf_prog.
+			 */
+			pr_err("bpf_jit: unknown opcode %02x\n", insn->code);
+			return -EINVAL;
+		}
+
+		ilen = prog - temp;
+		if (ilen > BPF_MAX_INSN_SIZE) {
+			pr_err("bpf_jit: fatal insn size error\n");
+			return -EFAULT;
+		}
+
+		if (image) {
+			/*
+			 * When populating the image, assert that:
+			 *
+			 *  i) We do not write beyond the allocated space, and
+			 * ii) addrs[i] did not change from the prior run, in order
+			 *     to validate assumptions made for computing branch
+			 *     displacements.
+			 */
+			if (unlikely(proglen + ilen > oldproglen ||
+				     proglen + ilen != addrs[i])) {
+				pr_err("bpf_jit: fatal error\n");
+				return -EFAULT;
+			}
+			memcpy(rw_image + proglen, temp, ilen);
+		}
+		proglen += ilen;
+		addrs[i] = proglen;
+		prog = temp;
+	}
+
+	if (image && excnt != bpf_prog->aux->num_exentries) {
+		pr_err("extable is not populated\n");
+		return -EFAULT;
+	}
+	return proglen;
+}
+
+static void save_regs(const struct btf_func_model *m, u8 **prog, int nr_regs,
+		      int stack_size)
+{
+	int i;
+
+	/* Store function arguments to stack.
+	 * For a function that accepts two pointers the sequence will be:
+	 * mov QWORD PTR [rbp-0x10],rdi
+	 * mov QWORD PTR [rbp-0x8],rsi
+	 */
+	for (i = 0; i < min(nr_regs, 6); i++)
+		emit_stx(prog, BPF_DW, BPF_REG_FP,
+			 i == 5 ? X86_REG_R9 : BPF_REG_1 + i,
+			 -(stack_size - i * 8));
+}
+
+static void restore_regs(const struct btf_func_model *m, u8 **prog, int nr_regs,
+			 int stack_size)
+{
+	int i;
+
+	/* Restore function arguments from stack.
+	 * For a function that accepts two pointers the sequence will be:
+	 * EMIT4(0x48, 0x8B, 0x7D, 0xF0); mov rdi,QWORD PTR [rbp-0x10]
+	 * EMIT4(0x48, 0x8B, 0x75, 0xF8); mov rsi,QWORD PTR [rbp-0x8]
+	 */
+	for (i = 0; i < min(nr_regs, 6); i++)
+		emit_ldx(prog, BPF_DW,
+			 i == 5 ? X86_REG_R9 : BPF_REG_1 + i,
+			 BPF_REG_FP,
+			 -(stack_size - i * 8));
+}
+
+static int invoke_bpf_prog(const struct btf_func_model *m, u8 **pprog,
+			   struct bpf_tramp_link *l, int stack_size,
+			   int run_ctx_off, bool save_ret)
+{
+	u8 *prog = *pprog;
+	u8 *jmp_insn;
+	int ctx_cookie_off = offsetof(struct bpf_tramp_run_ctx, bpf_cookie);
+	struct bpf_prog *p = l->link.prog;
+	u64 cookie = l->cookie;
+
+	/* mov rdi, cookie */
+	emit_mov_imm64(&prog, BPF_REG_1, (long) cookie >> 32, (u32) (long) cookie);
+
+	/* Prepare struct bpf_tramp_run_ctx.
+	 *
+	 * bpf_tramp_run_ctx is already preserved by
+	 * arch_prepare_bpf_trampoline().
+	 *
+	 * mov QWORD PTR [rbp - run_ctx_off + ctx_cookie_off], rdi
+	 */
+	emit_stx(&prog, BPF_DW, BPF_REG_FP, BPF_REG_1, -run_ctx_off + ctx_cookie_off);
+
+	/* arg1: mov rdi, progs[i] */
+	emit_mov_imm64(&prog, BPF_REG_1, (long) p >> 32, (u32) (long) p);
+	/* arg2: lea rsi, [rbp - ctx_cookie_off] */
+	EMIT4(0x48, 0x8D, 0x75, -run_ctx_off);
+
+	if (emit_call(&prog, bpf_trampoline_enter(p), prog))
+		return -EINVAL;
+	/* 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);
+	/* arg2: progs[i]->insnsi for interpreter */
+	if (!p->jited)
+		emit_mov_imm64(&prog, BPF_REG_2,
+			       (long) p->insnsi >> 32,
+			       (u32) (long) p->insnsi);
+	/* call JITed bpf program or interpreter */
+	if (emit_call(&prog, p->bpf_func, prog))
+		return -EINVAL;
+
+	/*
+	 * BPF_TRAMP_MODIFY_RETURN trampolines can modify the return
+	 * of the previous call which is then passed on the stack to
+	 * the next BPF program.
+	 *
+	 * BPF_TRAMP_FENTRY trampoline may need to return the return
+	 * value of BPF_PROG_TYPE_STRUCT_OPS prog.
+	 */
+	if (save_ret)
+		emit_stx(&prog, BPF_DW, BPF_REG_FP, BPF_REG_0, -8);
+
+	/* 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);
+	/* arg3: lea rdx, [rbp - run_ctx_off] */
+	EMIT4(0x48, 0x8D, 0x55, -run_ctx_off);
+	if (emit_call(&prog, bpf_trampoline_exit(p), prog))
+		return -EINVAL;
+
+	*pprog = prog;
+	return 0;
+}
+
+static void emit_align(u8 **pprog, u32 align)
+{
+	u8 *target, *prog = *pprog;
+
+	target = PTR_ALIGN(prog, align);
+	if (target != prog)
+		emit_nops(&prog, target - prog);
+
+	*pprog = prog;
+}
+
+static int emit_cond_near_jump(u8 **pprog, void *func, void *ip, u8 jmp_cond)
+{
+	u8 *prog = *pprog;
+	s64 offset;
+
+	offset = func - (ip + 2 + 4);
+	if (!is_simm32(offset)) {
+		pr_err("Target %p is out of range\n", func);
+		return -EINVAL;
+	}
+	EMIT2_off32(0x0F, jmp_cond + 0x10, offset);
+	*pprog = prog;
+	return 0;
+}
+
+static int invoke_bpf(const struct btf_func_model *m, u8 **pprog,
+		      struct bpf_tramp_links *tl, int stack_size,
+		      int run_ctx_off, bool save_ret)
+{
+	int i;
+	u8 *prog = *pprog;
+
+	for (i = 0; i < tl->nr_links; i++) {
+		if (invoke_bpf_prog(m, &prog, tl->links[i], stack_size,
+				    run_ctx_off, save_ret))
+			return -EINVAL;
+	}
+	*pprog = prog;
+	return 0;
+}
+
+static int invoke_bpf_mod_ret(const struct btf_func_model *m, u8 **pprog,
+			      struct bpf_tramp_links *tl, int stack_size,
+			      int run_ctx_off, u8 **branches)
+{
+	u8 *prog = *pprog;
+	int i;
+
+	/* The first fmod_ret program will receive a garbage return value.
+	 * Set this to 0 to avoid confusing the program.
+	 */
+	emit_mov_imm32(&prog, false, BPF_REG_0, 0);
+	emit_stx(&prog, BPF_DW, BPF_REG_FP, BPF_REG_0, -8);
+	for (i = 0; i < tl->nr_links; i++) {
+		if (invoke_bpf_prog(m, &prog, tl->links[i], stack_size, run_ctx_off, true))
+			return -EINVAL;
+
+		/* mod_ret prog stored return value into [rbp - 8]. Emit:
+		 * if (*(u64 *)(rbp - 8) !=  0)
+		 *	goto do_fexit;
+		 */
+		/* cmp QWORD PTR [rbp - 0x8], 0x0 */
+		EMIT4(0x48, 0x83, 0x7d, 0xf8); EMIT1(0x00);
+
+		/* Save the location of the branch and Generate 6 nops
+		 * (4 bytes for an offset and 2 bytes for the jump) These nops
+		 * are replaced with a conditional jump once do_fexit (i.e. the
+		 * start of the fexit invocation) is finalized.
+		 */
+		branches[i] = prog;
+		emit_nops(&prog, 4 + 2);
+	}
+
+	*pprog = prog;
+	return 0;
+}
+
+/* Example:
+ * __be16 eth_type_trans(struct sk_buff *skb, struct net_device *dev);
+ * its 'struct btf_func_model' will be nr_args=2
+ * The assembly code when eth_type_trans is executing after trampoline:
+ *
+ * push rbp
+ * mov rbp, rsp
+ * sub rsp, 16                     // space for skb and dev
+ * push rbx                        // temp regs to pass start time
+ * mov qword ptr [rbp - 16], rdi   // save skb pointer to stack
+ * mov qword ptr [rbp - 8], rsi    // save dev pointer to stack
+ * call __bpf_prog_enter           // rcu_read_lock and preempt_disable
+ * mov rbx, rax                    // remember start time in bpf stats are enabled
+ * lea rdi, [rbp - 16]             // R1==ctx of bpf prog
+ * call addr_of_jited_FENTRY_prog
+ * movabsq rdi, 64bit_addr_of_struct_bpf_prog  // unused if bpf stats are off
+ * mov rsi, rbx                    // prog start time
+ * call __bpf_prog_exit            // rcu_read_unlock, preempt_enable and stats math
+ * mov rdi, qword ptr [rbp - 16]   // restore skb pointer from stack
+ * mov rsi, qword ptr [rbp - 8]    // restore dev pointer from stack
+ * pop rbx
+ * leave
+ * ret
+ *
+ * eth_type_trans has 5 byte nop at the beginning. These 5 bytes will be
+ * replaced with 'call generated_bpf_trampoline'. When it returns
+ * eth_type_trans will continue executing with original skb and dev pointers.
+ *
+ * The assembly code when eth_type_trans is called from trampoline:
+ *
+ * push rbp
+ * mov rbp, rsp
+ * sub rsp, 24                     // space for skb, dev, return value
+ * push rbx                        // temp regs to pass start time
+ * mov qword ptr [rbp - 24], rdi   // save skb pointer to stack
+ * mov qword ptr [rbp - 16], rsi   // save dev pointer to stack
+ * call __bpf_prog_enter           // rcu_read_lock and preempt_disable
+ * mov rbx, rax                    // remember start time if bpf stats are enabled
+ * lea rdi, [rbp - 24]             // R1==ctx of bpf prog
+ * call addr_of_jited_FENTRY_prog  // bpf prog can access skb and dev
+ * movabsq rdi, 64bit_addr_of_struct_bpf_prog  // unused if bpf stats are off
+ * mov rsi, rbx                    // prog start time
+ * call __bpf_prog_exit            // rcu_read_unlock, preempt_enable and stats math
+ * mov rdi, qword ptr [rbp - 24]   // restore skb pointer from stack
+ * mov rsi, qword ptr [rbp - 16]   // restore dev pointer from stack
+ * call eth_type_trans+5           // execute body of eth_type_trans
+ * mov qword ptr [rbp - 8], rax    // save return value
+ * call __bpf_prog_enter           // rcu_read_lock and preempt_disable
+ * mov rbx, rax                    // remember start time in bpf stats are enabled
+ * lea rdi, [rbp - 24]             // R1==ctx of bpf prog
+ * call addr_of_jited_FEXIT_prog   // bpf prog can access skb, dev, return value
+ * movabsq rdi, 64bit_addr_of_struct_bpf_prog  // unused if bpf stats are off
+ * mov rsi, rbx                    // prog start time
+ * call __bpf_prog_exit            // rcu_read_unlock, preempt_enable and stats math
+ * mov rax, qword ptr [rbp - 8]    // restore eth_type_trans's return value
+ * pop rbx
+ * leave
+ * add rsp, 8                      // skip eth_type_trans's frame
+ * ret                             // return to its caller
+ */
+int arch_prepare_bpf_trampoline(struct bpf_tramp_image *im, void *image, void *image_end,
+				const struct btf_func_model *m, u32 flags,
+				struct bpf_tramp_links *tlinks,
+				void *func_addr)
+{
+	int i, ret, nr_regs = m->nr_args, stack_size = 0;
+	int regs_off, nregs_off, ip_off, run_ctx_off;
+	struct bpf_tramp_links *fentry = &tlinks[BPF_TRAMP_FENTRY];
+	struct bpf_tramp_links *fexit = &tlinks[BPF_TRAMP_FEXIT];
+	struct bpf_tramp_links *fmod_ret = &tlinks[BPF_TRAMP_MODIFY_RETURN];
+	void *orig_call = func_addr;
+	u8 **branches = NULL;
+	u8 *prog;
+	bool save_ret;
+
+	/* extra registers for struct arguments */
+	for (i = 0; i < m->nr_args; i++)
+		if (m->arg_flags[i] & BTF_FMODEL_STRUCT_ARG)
+			nr_regs += (m->arg_size[i] + 7) / 8 - 1;
+
+	/* x86-64 supports up to 6 arguments. 7+ can be added in the future */
+	if (nr_regs > 6)
+		return -ENOTSUPP;
+
+	/* Generated trampoline stack layout:
+	 *
+	 * RBP + 8         [ return address  ]
+	 * RBP + 0         [ RBP             ]
+	 *
+	 * RBP - 8         [ return value    ]  BPF_TRAMP_F_CALL_ORIG or
+	 *                                      BPF_TRAMP_F_RET_FENTRY_RET flags
+	 *
+	 *                 [ reg_argN        ]  always
+	 *                 [ ...             ]
+	 * RBP - regs_off  [ reg_arg1        ]  program's ctx pointer
+	 *
+	 * RBP - nregs_off [ regs count	     ]  always
+	 *
+	 * RBP - ip_off    [ traced function ]  BPF_TRAMP_F_IP_ARG flag
+	 *
+	 * RBP - run_ctx_off [ bpf_tramp_run_ctx ]
+	 * RSP                 [ tail_call_cnt ] BPF_TRAMP_F_TAIL_CALL_CTX
+	 */
+
+	/* room for return value of orig_call or fentry prog */
+	save_ret = flags & (BPF_TRAMP_F_CALL_ORIG | BPF_TRAMP_F_RET_FENTRY_RET);
+	if (save_ret)
+		stack_size += 8;
+
+	stack_size += nr_regs * 8;
+	regs_off = stack_size;
+
+	/* regs count  */
+	stack_size += 8;
+	nregs_off = stack_size;
+
+	if (flags & BPF_TRAMP_F_IP_ARG)
+		stack_size += 8; /* room for IP address argument */
+
+	ip_off = stack_size;
+
+	stack_size += (sizeof(struct bpf_tramp_run_ctx) + 7) & ~0x7;
+	run_ctx_off = stack_size;
+
+	if (flags & BPF_TRAMP_F_SKIP_FRAME) {
+		/* skip patched call instruction and point orig_call to actual
+		 * body of the kernel function.
+		 */
+		if (is_endbr(*(u32 *)orig_call))
+			orig_call += ENDBR_INSN_SIZE;
+		orig_call += X86_PATCH_SIZE;
+	}
+
+	prog = image;
+
+	EMIT_ENDBR();
+	EMIT1(0x55);		 /* push rbp */
+	EMIT3(0x48, 0x89, 0xE5); /* mov rbp, rsp */
+	EMIT4(0x48, 0x83, 0xEC, stack_size); /* sub rsp, stack_size */
+	if (flags & BPF_TRAMP_F_TAIL_CALL_CTX)
+		EMIT1(0x50);		/* push rax */
+	EMIT1(0x53);		 /* push rbx */
+
+	/* Store number of argument registers of the traced function:
+	 *   mov rax, nr_regs
+	 *   mov QWORD PTR [rbp - nregs_off], rax
+	 */
+	emit_mov_imm64(&prog, BPF_REG_0, 0, (u32) nr_regs);
+	emit_stx(&prog, BPF_DW, BPF_REG_FP, BPF_REG_0, -nregs_off);
+
+	if (flags & BPF_TRAMP_F_IP_ARG) {
+		/* Store IP address of the traced function:
+		 * movabsq rax, func_addr
+		 * mov QWORD PTR [rbp - ip_off], rax
+		 */
+		emit_mov_imm64(&prog, BPF_REG_0, (long) func_addr >> 32, (u32) (long) func_addr);
+		emit_stx(&prog, BPF_DW, BPF_REG_FP, BPF_REG_0, -ip_off);
+	}
+
+	save_regs(m, &prog, nr_regs, regs_off);
+
+	if (flags & BPF_TRAMP_F_CALL_ORIG) {
+		/* arg1: mov rdi, im */
+		emit_mov_imm64(&prog, BPF_REG_1, (long) im >> 32, (u32) (long) im);
+		if (emit_call(&prog, __bpf_tramp_enter, prog)) {
+			ret = -EINVAL;
+			goto cleanup;
+		}
+	}
+
+	if (fentry->nr_links)
+		if (invoke_bpf(m, &prog, fentry, regs_off, run_ctx_off,
+			       flags & BPF_TRAMP_F_RET_FENTRY_RET))
+			return -EINVAL;
+
+	if (fmod_ret->nr_links) {
+		branches = kcalloc(fmod_ret->nr_links, sizeof(u8 *),
+				   GFP_KERNEL);
+		if (!branches)
+			return -ENOMEM;
+
+		if (invoke_bpf_mod_ret(m, &prog, fmod_ret, regs_off,
+				       run_ctx_off, branches)) {
+			ret = -EINVAL;
+			goto cleanup;
+		}
+	}
+
+	if (flags & BPF_TRAMP_F_CALL_ORIG) {
+		restore_regs(m, &prog, nr_regs, regs_off);
+
+		if (flags & BPF_TRAMP_F_TAIL_CALL_CTX)
+			/* Before calling the original function, restore the
+			 * tail_call_cnt from stack to rax.
+			 */
+			RESTORE_TAIL_CALL_CNT(stack_size);
+
+		if (flags & BPF_TRAMP_F_ORIG_STACK) {
+			emit_ldx(&prog, BPF_DW, BPF_REG_6, BPF_REG_FP, 8);
+			EMIT2(0xff, 0xd3); /* call *rbx */
+		} else {
+			/* call original function */
+			if (emit_call(&prog, orig_call, prog)) {
+				ret = -EINVAL;
+				goto cleanup;
+			}
+		}
+		/* remember return value in a stack for bpf prog to access */
+		emit_stx(&prog, BPF_DW, BPF_REG_FP, BPF_REG_0, -8);
+		im->ip_after_call = prog;
+		memcpy(prog, x86_nops[5], X86_PATCH_SIZE);
+		prog += X86_PATCH_SIZE;
+	}
+
+	if (fmod_ret->nr_links) {
+		/* From Intel 64 and IA-32 Architectures Optimization
+		 * Reference Manual, 3.4.1.4 Code Alignment, Assembly/Compiler
+		 * Coding Rule 11: All branch targets should be 16-byte
+		 * aligned.
+		 */
+		emit_align(&prog, 16);
+		/* Update the branches saved in invoke_bpf_mod_ret with the
+		 * aligned address of do_fexit.
+		 */
+		for (i = 0; i < fmod_ret->nr_links; i++)
+			emit_cond_near_jump(&branches[i], prog, branches[i],
+					    X86_JNE);
+	}
+
+	if (fexit->nr_links)
+		if (invoke_bpf(m, &prog, fexit, regs_off, run_ctx_off, false)) {
+			ret = -EINVAL;
+			goto cleanup;
+		}
+
+	if (flags & BPF_TRAMP_F_RESTORE_REGS)
+		restore_regs(m, &prog, nr_regs, regs_off);
+
+	/* This needs to be done regardless. If there were fmod_ret programs,
+	 * the return value is only updated on the stack and still needs to be
+	 * restored to R0.
+	 */
+	if (flags & BPF_TRAMP_F_CALL_ORIG) {
+		im->ip_epilogue = prog;
+		/* arg1: mov rdi, im */
+		emit_mov_imm64(&prog, BPF_REG_1, (long) im >> 32, (u32) (long) im);
+		if (emit_call(&prog, __bpf_tramp_exit, prog)) {
+			ret = -EINVAL;
+			goto cleanup;
+		}
+	} else if (flags & BPF_TRAMP_F_TAIL_CALL_CTX)
+		/* Before running the original function, restore the
+		 * tail_call_cnt from stack to rax.
+		 */
+		RESTORE_TAIL_CALL_CNT(stack_size);
+
+	/* restore return value of orig_call or fentry prog back into RAX */
+	if (save_ret)
+		emit_ldx(&prog, BPF_DW, BPF_REG_0, BPF_REG_FP, -8);
+
+	EMIT1(0x5B); /* pop rbx */
+	EMIT1(0xC9); /* leave */
+	if (flags & BPF_TRAMP_F_SKIP_FRAME)
+		/* skip our return address and return to parent */
+		EMIT4(0x48, 0x83, 0xC4, 8); /* add rsp, 8 */
+	emit_return(&prog, prog);
+	/* Make sure the trampoline generation logic doesn't overflow */
+	if (WARN_ON_ONCE(prog > (u8 *)image_end - BPF_INSN_SAFETY)) {
+		ret = -EFAULT;
+		goto cleanup;
+	}
+	ret = prog - (u8 *)image;
+
+cleanup:
+	kfree(branches);
+	return ret;
+}
+
+static int emit_bpf_dispatcher(u8 **pprog, int a, int b, s64 *progs, u8 *image, u8 *buf)
+{
+	u8 *jg_reloc, *prog = *pprog;
+	int pivot, err, jg_bytes = 1;
+	s64 jg_offset;
+
+	if (a == b) {
+		/* Leaf node of recursion, i.e. not a range of indices
+		 * anymore.
+		 */
+		EMIT1(add_1mod(0x48, BPF_REG_3));	/* cmp rdx,func */
+		if (!is_simm32(progs[a]))
+			return -1;
+		EMIT2_off32(0x81, add_1reg(0xF8, BPF_REG_3),
+			    progs[a]);
+		err = emit_cond_near_jump(&prog,	/* je func */
+					  (void *)progs[a], image + (prog - buf),
+					  X86_JE);
+		if (err)
+			return err;
+
+		emit_indirect_jump(&prog, 2 /* rdx */, image + (prog - buf));
+
+		*pprog = prog;
+		return 0;
+	}
+
+	/* Not a leaf node, so we pivot, and recursively descend into
+	 * the lower and upper ranges.
+	 */
+	pivot = (b - a) / 2;
+	EMIT1(add_1mod(0x48, BPF_REG_3));		/* cmp rdx,func */
+	if (!is_simm32(progs[a + pivot]))
+		return -1;
+	EMIT2_off32(0x81, add_1reg(0xF8, BPF_REG_3), progs[a + pivot]);
+
+	if (pivot > 2) {				/* jg upper_part */
+		/* Require near jump. */
+		jg_bytes = 4;
+		EMIT2_off32(0x0F, X86_JG + 0x10, 0);
+	} else {
+		EMIT2(X86_JG, 0);
+	}
+	jg_reloc = prog;
+
+	err = emit_bpf_dispatcher(&prog, a, a + pivot,	/* emit lower_part */
+				  progs, image, buf);
+	if (err)
+		return err;
+
+	/* From Intel 64 and IA-32 Architectures Optimization
+	 * Reference Manual, 3.4.1.4 Code Alignment, Assembly/Compiler
+	 * Coding Rule 11: All branch targets should be 16-byte
+	 * aligned.
+	 */
+	emit_align(&prog, 16);
+	jg_offset = prog - jg_reloc;
+	emit_code(jg_reloc - jg_bytes, jg_offset, jg_bytes);
+
+	err = emit_bpf_dispatcher(&prog, a + pivot + 1,	/* emit upper_part */
+				  b, progs, image, buf);
+	if (err)
+		return err;
+
+	*pprog = prog;
+	return 0;
+}
+
+static int cmp_ips(const void *a, const void *b)
+{
+	const s64 *ipa = a;
+	const s64 *ipb = b;
+
+	if (*ipa > *ipb)
+		return 1;
+	if (*ipa < *ipb)
+		return -1;
+	return 0;
+}
+
+int arch_prepare_bpf_dispatcher(void *image, void *buf, s64 *funcs, int num_funcs)
+{
+	u8 *prog = buf;
+
+	sort(funcs, num_funcs, sizeof(funcs[0]), cmp_ips, NULL);
+	return emit_bpf_dispatcher(&prog, 0, num_funcs - 1, funcs, image, buf);
+}
+
+struct x64_jit_data {
+	struct bpf_binary_header *rw_header;
+	struct bpf_binary_header *header;
+	int *addrs;
+	u8 *image;
+	int proglen;
+	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 *rw_header = NULL;
+	struct bpf_binary_header *header = NULL;
+	struct bpf_prog *tmp, *orig_prog = prog;
+	struct x64_jit_data *jit_data;
+	int proglen, oldproglen = 0;
+	struct jit_context ctx = {};
+	bool tmp_blinded = false;
+	bool extra_pass = false;
+	bool padding = false;
+	u8 *rw_image = NULL;
+	u8 *image = NULL;
+	int *addrs;
+	int pass;
+	int i;
+
+	if (!prog->jit_requested)
+		return orig_prog;
+
+	tmp = bpf_jit_blind_constants(prog);
+	/*
+	 * If blinding was requested and we failed during blinding,
+	 * we must fall back to the interpreter.
+	 */
+	if (IS_ERR(tmp))
+		return orig_prog;
+	if (tmp != prog) {
+		tmp_blinded = true;
+		prog = tmp;
+	}
+
+	jit_data = prog->aux->jit_data;
+	if (!jit_data) {
+		jit_data = kzalloc(sizeof(*jit_data), GFP_KERNEL);
+		if (!jit_data) {
+			prog = orig_prog;
+			goto out;
+		}
+		prog->aux->jit_data = jit_data;
+	}
+	addrs = jit_data->addrs;
+	if (addrs) {
+		ctx = jit_data->ctx;
+		oldproglen = jit_data->proglen;
+		image = jit_data->image;
+		header = jit_data->header;
+		rw_header = jit_data->rw_header;
+		rw_image = (void *)rw_header + ((void *)image - (void *)header);
+		extra_pass = true;
+		padding = true;
+		goto skip_init_addrs;
+	}
+	addrs = kvmalloc_array(prog->len + 1, sizeof(*addrs), GFP_KERNEL);
+	if (!addrs) {
+		prog = orig_prog;
+		goto out_addrs;
+	}
+
+	/*
+	 * Before first pass, make a rough estimation of addrs[]
+	 * each BPF instruction is translated to less than 64 bytes
+	 */
+	for (proglen = 0, i = 0; i <= prog->len; i++) {
+		proglen += 64;
+		addrs[i] = proglen;
+	}
+	ctx.cleanup_addr = proglen;
+skip_init_addrs:
+
+	/*
+	 * JITed image shrinks with every pass and the loop iterates
+	 * until the image stops shrinking. Very large BPF programs
+	 * may converge on the last pass. In such case do one more
+	 * pass to emit the final image.
+	 */
+	for (pass = 0; pass < MAX_PASSES || image; pass++) {
+		if (!padding && pass >= PADDING_PASSES)
+			padding = true;
+		proglen = do_jit(prog, addrs, image, rw_image, oldproglen, &ctx, padding);
+		if (proglen <= 0) {
+out_image:
+			image = NULL;
+			if (header) {
+				bpf_arch_text_copy(&header->size, &rw_header->size,
+						   sizeof(rw_header->size));
+				bpf_jit_binary_pack_free(header, rw_header);
+			}
+			/* Fall back to interpreter mode */
+			prog = orig_prog;
+			if (extra_pass) {
+				prog->bpf_func = NULL;
+				prog->jited = 0;
+				prog->jited_len = 0;
+			}
+			goto out_addrs;
+		}
+		if (image) {
+			if (proglen != oldproglen) {
+				pr_err("bpf_jit: proglen=%d != oldproglen=%d\n",
+				       proglen, oldproglen);
+				goto out_image;
+			}
+			break;
+		}
+		if (proglen == oldproglen) {
+			/*
+			 * The number of entries in extable is the number of BPF_LDX
+			 * insns that access kernel memory via "pointer to BTF type".
+			 * The verifier changed their opcode from LDX|MEM|size
+			 * to LDX|PROBE_MEM|size to make JITing easier.
+			 */
+			u32 align = __alignof__(struct exception_table_entry);
+			u32 extable_size = prog->aux->num_exentries *
+				sizeof(struct exception_table_entry);
+
+			/* allocate module memory for x86 insns and extable */
+			header = bpf_jit_binary_pack_alloc(roundup(proglen, align) + extable_size,
+							   &image, align, &rw_header, &rw_image,
+							   jit_fill_hole);
+			if (!header) {
+				prog = orig_prog;
+				goto out_addrs;
+			}
+			prog->aux->extable = (void *) image + roundup(proglen, align);
+		}
+		oldproglen = proglen;
+		cond_resched();
+	}
+
+	if (bpf_jit_enable > 1)
+		bpf_jit_dump(prog->len, proglen, pass + 1, rw_image);
+
+	if (image) {
+		if (!prog->is_func || extra_pass) {
+			/*
+			 * bpf_jit_binary_pack_finalize fails in two scenarios:
+			 *   1) header is not pointing to proper module memory;
+			 *   2) the arch doesn't support bpf_arch_text_copy().
+			 *
+			 * Both cases are serious bugs and justify WARN_ON.
+			 */
+			if (WARN_ON(bpf_jit_binary_pack_finalize(prog, header, rw_header))) {
+				/* header has been freed */
+				header = NULL;
+				goto out_image;
+			}
+
+			bpf_tail_call_direct_fixup(prog);
+		} else {
+			jit_data->addrs = addrs;
+			jit_data->ctx = ctx;
+			jit_data->proglen = proglen;
+			jit_data->image = image;
+			jit_data->header = header;
+			jit_data->rw_header = rw_header;
+		}
+		prog->bpf_func = (void *)image;
+		prog->jited = 1;
+		prog->jited_len = proglen;
+	} else {
+		prog = orig_prog;
+	}
+
+	if (!image || !prog->is_func || extra_pass) {
+		if (image)
+			bpf_prog_fill_jited_linfo(prog, addrs + 1);
+out_addrs:
+		kvfree(addrs);
+		kfree(jit_data);
+		prog->aux->jit_data = NULL;
+	}
+out:
+	if (tmp_blinded)
+		bpf_jit_prog_release_other(prog, prog == orig_prog ?
+					   tmp : orig_prog);
+	return prog;
+}
+
+bool bpf_jit_supports_kfunc_call(void)
+{
+	return true;
+}
+
+void *bpf_arch_text_copy(void *dst, void *src, size_t len)
+{
+	if (text_poke_copy(dst, src, len) == NULL)
+		return ERR_PTR(-EINVAL);
+	return dst;
+}
+
+/* Indicate the JIT backend supports mixing bpf2bpf and tailcalls. */
+bool bpf_jit_supports_subprog_tailcalls(void)
+{
+	return true;
+}
+
+void bpf_jit_free(struct bpf_prog *prog)
+{
+	if (prog->jited) {
+		struct x64_jit_data *jit_data = prog->aux->jit_data;
+		struct bpf_binary_header *hdr;
+
+		/*
+		 * If we fail the final pass of JIT (from jit_subprogs),
+		 * the program may not be finalized yet. Call finalize here
+		 * before freeing it.
+		 */
+		if (jit_data) {
+			bpf_jit_binary_pack_finalize(prog, jit_data->header,
+						     jit_data->rw_header);
+			kvfree(jit_data->addrs);
+			kfree(jit_data);
+		}
+		hdr = bpf_jit_binary_pack_hdr(prog);
+		bpf_jit_binary_pack_free(hdr, NULL);
+		WARN_ON_ONCE(!bpf_prog_kallsyms_verify_off(prog));
+	}
+
+	bpf_prog_unlock_free(prog);
+}
+
+void bpf_arch_poke_desc_update(struct bpf_jit_poke_descriptor *poke,
+			       struct bpf_prog *new, struct bpf_prog *old)
+{
+	u8 *old_addr, *new_addr, *old_bypass_addr;
+	int ret;
+
+	old_bypass_addr = old ? NULL : poke->bypass_addr;
+	old_addr = old ? (u8 *)old->bpf_func + poke->adj_off : NULL;
+	new_addr = new ? (u8 *)new->bpf_func + poke->adj_off : NULL;
+
+	/*
+	 * On program loading or teardown, the program's kallsym entry
+	 * might not be in place, so we use __bpf_arch_text_poke to skip
+	 * the kallsyms check.
+	 */
+	if (new) {
+		ret = __bpf_arch_text_poke(poke->tailcall_target,
+					   BPF_MOD_JUMP,
+					   old_addr, new_addr);
+		BUG_ON(ret < 0);
+		if (!old) {
+			ret = __bpf_arch_text_poke(poke->tailcall_bypass,
+						   BPF_MOD_JUMP,
+						   poke->bypass_addr,
+						   NULL);
+			BUG_ON(ret < 0);
+		}
+	} else {
+		ret = __bpf_arch_text_poke(poke->tailcall_bypass,
+					   BPF_MOD_JUMP,
+					   old_bypass_addr,
+					   poke->bypass_addr);
+		BUG_ON(ret < 0);
+		/* let other CPUs finish the execution of program
+		 * so that it will not possible to expose them
+		 * to invalid nop, stack unwind, nop state
+		 */
+		if (!ret)
+			synchronize_rcu();
+		ret = __bpf_arch_text_poke(poke->tailcall_target,
+					   BPF_MOD_JUMP,
+					   old_addr, NULL);
+		BUG_ON(ret < 0);
+	}
+}