kprobes_trampoline.S 1.8 KB

1234567891011121314151617181920212223242526272829303132333435363738394041424344454647484950515253545556575859606162636465666768697071727374757677787980818283848586
  1. /* SPDX-License-Identifier: GPL-2.0 */
  2. /*
  3. * trampoline entry and return code for kretprobes.
  4. */
  5. #include <linux/linkage.h>
  6. #include <asm/asm-offsets.h>
  7. #include <asm/assembler.h>
  8. .text
  9. .macro save_all_base_regs
  10. stp x0, x1, [sp, #S_X0]
  11. stp x2, x3, [sp, #S_X2]
  12. stp x4, x5, [sp, #S_X4]
  13. stp x6, x7, [sp, #S_X6]
  14. stp x8, x9, [sp, #S_X8]
  15. stp x10, x11, [sp, #S_X10]
  16. stp x12, x13, [sp, #S_X12]
  17. stp x14, x15, [sp, #S_X14]
  18. stp x16, x17, [sp, #S_X16]
  19. stp x18, x19, [sp, #S_X18]
  20. stp x20, x21, [sp, #S_X20]
  21. stp x22, x23, [sp, #S_X22]
  22. stp x24, x25, [sp, #S_X24]
  23. stp x26, x27, [sp, #S_X26]
  24. stp x28, x29, [sp, #S_X28]
  25. add x0, sp, #PT_REGS_SIZE
  26. stp lr, x0, [sp, #S_LR]
  27. /*
  28. * Construct a useful saved PSTATE
  29. */
  30. mrs x0, nzcv
  31. mrs x1, daif
  32. orr x0, x0, x1
  33. mrs x1, CurrentEL
  34. orr x0, x0, x1
  35. mrs x1, SPSel
  36. orr x0, x0, x1
  37. stp xzr, x0, [sp, #S_PC]
  38. .endm
  39. .macro restore_all_base_regs
  40. ldr x0, [sp, #S_PSTATE]
  41. and x0, x0, #(PSR_N_BIT | PSR_Z_BIT | PSR_C_BIT | PSR_V_BIT)
  42. msr nzcv, x0
  43. ldp x0, x1, [sp, #S_X0]
  44. ldp x2, x3, [sp, #S_X2]
  45. ldp x4, x5, [sp, #S_X4]
  46. ldp x6, x7, [sp, #S_X6]
  47. ldp x8, x9, [sp, #S_X8]
  48. ldp x10, x11, [sp, #S_X10]
  49. ldp x12, x13, [sp, #S_X12]
  50. ldp x14, x15, [sp, #S_X14]
  51. ldp x16, x17, [sp, #S_X16]
  52. ldp x18, x19, [sp, #S_X18]
  53. ldp x20, x21, [sp, #S_X20]
  54. ldp x22, x23, [sp, #S_X22]
  55. ldp x24, x25, [sp, #S_X24]
  56. ldp x26, x27, [sp, #S_X26]
  57. ldp x28, x29, [sp, #S_X28]
  58. .endm
  59. SYM_CODE_START(__kretprobe_trampoline)
  60. sub sp, sp, #PT_REGS_SIZE
  61. save_all_base_regs
  62. /* Setup a frame pointer. */
  63. add x29, sp, #S_FP
  64. mov x0, sp
  65. bl trampoline_probe_handler
  66. /*
  67. * Replace trampoline address in lr with actual orig_ret_addr return
  68. * address.
  69. */
  70. mov lr, x0
  71. /* The frame pointer (x29) is restored with other registers. */
  72. restore_all_base_regs
  73. add sp, sp, #PT_REGS_SIZE
  74. ret
  75. SYM_CODE_END(__kretprobe_trampoline)