kprobes_trampoline.S (1852B)
1/* SPDX-License-Identifier: GPL-2.0 */ 2/* 3 * trampoline entry and return code for kretprobes. 4 */ 5 6#include <linux/linkage.h> 7#include <asm/asm-offsets.h> 8#include <asm/assembler.h> 9 10 .text 11 12 .macro save_all_base_regs 13 stp x0, x1, [sp, #S_X0] 14 stp x2, x3, [sp, #S_X2] 15 stp x4, x5, [sp, #S_X4] 16 stp x6, x7, [sp, #S_X6] 17 stp x8, x9, [sp, #S_X8] 18 stp x10, x11, [sp, #S_X10] 19 stp x12, x13, [sp, #S_X12] 20 stp x14, x15, [sp, #S_X14] 21 stp x16, x17, [sp, #S_X16] 22 stp x18, x19, [sp, #S_X18] 23 stp x20, x21, [sp, #S_X20] 24 stp x22, x23, [sp, #S_X22] 25 stp x24, x25, [sp, #S_X24] 26 stp x26, x27, [sp, #S_X26] 27 stp x28, x29, [sp, #S_X28] 28 add x0, sp, #PT_REGS_SIZE 29 stp lr, x0, [sp, #S_LR] 30 /* 31 * Construct a useful saved PSTATE 32 */ 33 mrs x0, nzcv 34 mrs x1, daif 35 orr x0, x0, x1 36 mrs x1, CurrentEL 37 orr x0, x0, x1 38 mrs x1, SPSel 39 orr x0, x0, x1 40 stp xzr, x0, [sp, #S_PC] 41 .endm 42 43 .macro restore_all_base_regs 44 ldr x0, [sp, #S_PSTATE] 45 and x0, x0, #(PSR_N_BIT | PSR_Z_BIT | PSR_C_BIT | PSR_V_BIT) 46 msr nzcv, x0 47 ldp x0, x1, [sp, #S_X0] 48 ldp x2, x3, [sp, #S_X2] 49 ldp x4, x5, [sp, #S_X4] 50 ldp x6, x7, [sp, #S_X6] 51 ldp x8, x9, [sp, #S_X8] 52 ldp x10, x11, [sp, #S_X10] 53 ldp x12, x13, [sp, #S_X12] 54 ldp x14, x15, [sp, #S_X14] 55 ldp x16, x17, [sp, #S_X16] 56 ldp x18, x19, [sp, #S_X18] 57 ldp x20, x21, [sp, #S_X20] 58 ldp x22, x23, [sp, #S_X22] 59 ldp x24, x25, [sp, #S_X24] 60 ldp x26, x27, [sp, #S_X26] 61 ldp x28, x29, [sp, #S_X28] 62 .endm 63 64SYM_CODE_START(__kretprobe_trampoline) 65 sub sp, sp, #PT_REGS_SIZE 66 67 save_all_base_regs 68 69 /* Setup a frame pointer. */ 70 add x29, sp, #S_FP 71 72 mov x0, sp 73 bl trampoline_probe_handler 74 /* 75 * Replace trampoline address in lr with actual orig_ret_addr return 76 * address. 77 */ 78 mov lr, x0 79 80 /* The frame pointer (x29) is restored with other registers. */ 81 restore_all_base_regs 82 83 add sp, sp, #PT_REGS_SIZE 84 ret 85 86SYM_CODE_END(__kretprobe_trampoline)