1 ;; @file 2 ; This is the assembly code for page fault handler hook. 3 ; 4 ; Copyright (c) 2015, Intel Corporation. All rights reserved.<BR> 5 ; 6 ; This program and the accompanying materials 7 ; are licensed and made available under the terms and conditions of the BSD License 8 ; which accompanies this distribution. The full text of the license may be found at 9 ; http://opensource.org/licenses/bsd-license.php 10 ; 11 ; THE PROGRAM IS DISTRIBUTED UNDER THE BSD LICENSE ON AN "AS IS" BASIS, 12 ; WITHOUT WARRANTIES OR REPRESENTATIONS OF ANY KIND, EITHER EXPRESS OR IMPLIED. 13 ; 14 ;; 15 16 extern ASM_PFX(PageFaultHandler) 17 18 DEFAULT REL 19 SECTION .text 20 21 global ASM_PFX(PageFaultHandlerHook) 22 ASM_PFX(PageFaultHandlerHook): 23 add rsp, -0x10 24 ; save rax 25 mov [rsp + 0x8], rax 26 27 ;push rax ; save all volatile registers 28 push rcx 29 push rdx 30 push r8 31 push r9 32 push r10 33 push r11 34 ; save volatile fp registers 35 ; 68h + 08h(for alignment) 36 add rsp, -0x70 37 stmxcsr [rsp + 0x60] 38 movdqa [rsp + 0x0], xmm0 39 movdqa [rsp + 0x10], xmm1 40 movdqa [rsp + 0x20], xmm2 41 movdqa [rsp + 0x30], xmm3 42 movdqa [rsp + 0x40], xmm4 43 movdqa [rsp + 0x50], xmm5 44 45 add rsp, -0x20 46 call ASM_PFX(PageFaultHandler) 47 add rsp, 0x20 48 49 ; load volatile fp registers 50 ldmxcsr [rsp + 0x60] 51 movdqa xmm0, [rsp + 0x0] 52 movdqa xmm1, [rsp + 0x10] 53 movdqa xmm2, [rsp + 0x20] 54 movdqa xmm3, [rsp + 0x30] 55 movdqa xmm4, [rsp + 0x40] 56 movdqa xmm5, [rsp + 0x50] 57 add rsp, 0x70 58 59 pop r11 60 pop r10 61 pop r9 62 pop r8 63 pop rdx 64 pop rcx 65 ;pop rax ; restore all volatile registers 66 67 add rsp, 0x10 68 69 ; rax returned from PageFaultHandler is NULL or OriginalHandler address 70 ; NULL if the page fault is handled by PageFaultHandler 71 ; OriginalHandler address if the page fault is not handled by PageFaultHandler 72 test rax, rax 73 74 ; save OriginalHandler address 75 mov [rsp - 0x10], rax 76 ; restore rax 77 mov rax, [rsp - 0x8] 78 79 jz .0 80 81 ; jump to OriginalHandler 82 jmp qword [rsp - 0x10] 83 84 .0: 85 add rsp, 0x8 ; skip error code for PF 86 iretq 87 88
