Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1 | /* |
Ingo Molnar | 54ad726 | 2015-06-05 13:02:28 +0200 | [diff] [blame] | 2 | * Compatibility mode system call entry point for x86-64. |
| 3 | * |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 4 | * Copyright 2000-2002 Andi Kleen, SuSE Labs. |
Ingo Molnar | 54ad726 | 2015-06-05 13:02:28 +0200 | [diff] [blame] | 5 | */ |
Ingo Molnar | d36f947 | 2015-06-03 18:29:26 +0200 | [diff] [blame] | 6 | #include "calling.h" |
Sam Ravnborg | e2d5df9 | 2005-09-09 21:28:48 +0200 | [diff] [blame] | 7 | #include <asm/asm-offsets.h> |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 8 | #include <asm/current.h> |
| 9 | #include <asm/errno.h> |
Ingo Molnar | 54ad726 | 2015-06-05 13:02:28 +0200 | [diff] [blame] | 10 | #include <asm/ia32_unistd.h> |
| 11 | #include <asm/thread_info.h> |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 12 | #include <asm/segment.h> |
Ingo Molnar | 2601e64 | 2006-07-03 00:24:45 -0700 | [diff] [blame] | 13 | #include <asm/irqflags.h> |
H. Peter Anvin | 1ce6f86 | 2012-04-20 12:19:50 -0700 | [diff] [blame] | 14 | #include <asm/asm.h> |
H. Peter Anvin | 63bcff2 | 2012-09-21 12:43:12 -0700 | [diff] [blame] | 15 | #include <asm/smap.h> |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 16 | #include <linux/linkage.h> |
Eric Paris | d7e7528 | 2012-01-03 14:23:06 -0500 | [diff] [blame] | 17 | #include <linux/err.h> |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 18 | |
Jiri Olsa | ea71454 | 2011-03-07 19:10:39 +0100 | [diff] [blame] | 19 | .section .entry.text, "ax" |
| 20 | |
Jeremy Fitzhardinge | 2be2998 | 2008-06-25 00:19:28 -0400 | [diff] [blame] | 21 | #ifdef CONFIG_PARAVIRT |
| 22 | ENTRY(native_usergs_sysret32) |
| 23 | swapgs |
| 24 | sysretl |
| 25 | ENDPROC(native_usergs_sysret32) |
Jeremy Fitzhardinge | 2be2998 | 2008-06-25 00:19:28 -0400 | [diff] [blame] | 26 | #endif |
| 27 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 28 | /* |
Ingo Molnar | 54ad726 | 2015-06-05 13:02:28 +0200 | [diff] [blame] | 29 | * 32-bit SYSENTER instruction entry. |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 30 | * |
Denys Vlasenko | b87cf63 | 2015-02-26 14:40:32 -0800 | [diff] [blame] | 31 | * SYSENTER loads ss, rsp, cs, and rip from previously programmed MSRs. |
| 32 | * IF and VM in rflags are cleared (IOW: interrupts are off). |
| 33 | * SYSENTER does not save anything on the stack, |
| 34 | * and does not save old rip (!!!) and rflags. |
| 35 | * |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 36 | * Arguments: |
Denys Vlasenko | b87cf63 | 2015-02-26 14:40:32 -0800 | [diff] [blame] | 37 | * eax system call number |
| 38 | * ebx arg1 |
| 39 | * ecx arg2 |
| 40 | * edx arg3 |
| 41 | * esi arg4 |
| 42 | * edi arg5 |
| 43 | * ebp user stack |
| 44 | * 0(%ebp) arg6 |
| 45 | * |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 46 | * This is purely a fast path. For anything complicated we use the int 0x80 |
Denys Vlasenko | b87cf63 | 2015-02-26 14:40:32 -0800 | [diff] [blame] | 47 | * path below. We set up a complete hardware stack frame to share code |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 48 | * with the int 0x80 path. |
Denys Vlasenko | b87cf63 | 2015-02-26 14:40:32 -0800 | [diff] [blame] | 49 | */ |
Ingo Molnar | 4c8cd0c | 2015-06-08 08:33:56 +0200 | [diff] [blame] | 50 | ENTRY(entry_SYSENTER_compat) |
Andy Lutomirski | b611acf | 2015-10-05 17:47:55 -0700 | [diff] [blame] | 51 | /* Interrupts are off on entry. */ |
Jeremy Fitzhardinge | 457da70 | 2008-06-26 07:28:51 -0700 | [diff] [blame] | 52 | SWAPGS_UNSAFE_STACK |
Denys Vlasenko | 3a23208 | 2015-04-24 17:31:35 +0200 | [diff] [blame] | 53 | movq PER_CPU_VAR(cpu_current_top_of_stack), %rsp |
Denys Vlasenko | a232e3d | 2015-03-27 11:36:20 +0100 | [diff] [blame] | 54 | |
Denys Vlasenko | 4ee8ec1 | 2015-03-27 11:36:21 +0100 | [diff] [blame] | 55 | /* Zero-extending 32-bit regs, do not remove */ |
| 56 | movl %ebp, %ebp |
| 57 | movl %eax, %eax |
| 58 | |
Denys Vlasenko | 4c9c0e9 | 2015-03-31 19:00:04 +0200 | [diff] [blame] | 59 | movl ASM_THREAD_INFO(TI_sysenter_return, %rsp, 0), %r10d |
Denys Vlasenko | 4c9c0e9 | 2015-03-31 19:00:04 +0200 | [diff] [blame] | 60 | |
| 61 | /* Construct struct pt_regs on stack */ |
Ingo Molnar | 131484c | 2015-05-28 12:21:47 +0200 | [diff] [blame] | 62 | pushq $__USER32_DS /* pt_regs->ss */ |
| 63 | pushq %rbp /* pt_regs->sp */ |
Andy Lutomirski | b611acf | 2015-10-05 17:47:55 -0700 | [diff] [blame] | 64 | |
| 65 | /* |
| 66 | * Push flags. This is nasty. First, interrupts are currently |
| 67 | * off, but we need pt_regs->flags to have IF set. Second, even |
| 68 | * if TF was set when SYSENTER started, it's clear by now. We fix |
| 69 | * that later using TIF_SINGLESTEP. |
| 70 | */ |
| 71 | pushfq /* pt_regs->flags (except IF = 0) */ |
| 72 | orl $X86_EFLAGS_IF, (%rsp) /* Fix saved flags */ |
| 73 | |
Ingo Molnar | 131484c | 2015-05-28 12:21:47 +0200 | [diff] [blame] | 74 | pushq $__USER32_CS /* pt_regs->cs */ |
Ingo Molnar | 54ad726 | 2015-06-05 13:02:28 +0200 | [diff] [blame] | 75 | pushq %r10 /* pt_regs->ip = thread_info->sysenter_return */ |
Ingo Molnar | 131484c | 2015-05-28 12:21:47 +0200 | [diff] [blame] | 76 | pushq %rax /* pt_regs->orig_ax */ |
| 77 | pushq %rdi /* pt_regs->di */ |
| 78 | pushq %rsi /* pt_regs->si */ |
| 79 | pushq %rdx /* pt_regs->dx */ |
| 80 | pushq %rcx /* pt_regs->cx */ |
| 81 | pushq $-ENOSYS /* pt_regs->ax */ |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 82 | cld |
Ingo Molnar | 54ad726 | 2015-06-05 13:02:28 +0200 | [diff] [blame] | 83 | sub $(10*8), %rsp /* pt_regs->r8-11, bp, bx, r12-15 not saved */ |
Denys Vlasenko | 4c9c0e9 | 2015-03-31 19:00:04 +0200 | [diff] [blame] | 84 | |
Denys Vlasenko | b87cf63 | 2015-02-26 14:40:32 -0800 | [diff] [blame] | 85 | /* |
Andy Lutomirski | 8c7aa69 | 2014-10-01 11:49:04 -0700 | [diff] [blame] | 86 | * Sysenter doesn't filter flags, so we need to clear NT |
| 87 | * ourselves. To save a few cycles, we can check whether |
| 88 | * NT was set instead of doing an unconditional popfq. |
Andy Lutomirski | b611acf | 2015-10-05 17:47:55 -0700 | [diff] [blame] | 89 | * This needs to happen before enabling interrupts so that |
| 90 | * we don't get preempted with NT set. |
Andy Lutomirski | 8c7aa69 | 2014-10-01 11:49:04 -0700 | [diff] [blame] | 91 | */ |
Ingo Molnar | 54ad726 | 2015-06-05 13:02:28 +0200 | [diff] [blame] | 92 | testl $X86_EFLAGS_NT, EFLAGS(%rsp) |
| 93 | jnz sysenter_fix_flags |
Andy Lutomirski | 8c7aa69 | 2014-10-01 11:49:04 -0700 | [diff] [blame] | 94 | sysenter_flags_fixed: |
| 95 | |
Andy Lutomirski | e62a254 | 2015-10-05 17:48:02 -0700 | [diff] [blame] | 96 | /* Temporary: SYSENTER is disabled. */ |
| 97 | #ifdef CONFIG_CONTEXT_TRACKING |
| 98 | call enter_from_user_mode |
| 99 | #endif |
| 100 | ENABLE_INTERRUPTS(CLBR_NONE) |
| 101 | movl $11, %edi |
| 102 | call do_exit |
| 103 | |
Andy Lutomirski | 2ec6797 | 2015-10-05 17:48:04 -0700 | [diff] [blame] | 104 | /* Unreachable. */ |
| 105 | ud2 |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 106 | |
Andy Lutomirski | 8c7aa69 | 2014-10-01 11:49:04 -0700 | [diff] [blame] | 107 | sysenter_fix_flags: |
Andy Lutomirski | b611acf | 2015-10-05 17:47:55 -0700 | [diff] [blame] | 108 | pushq $X86_EFLAGS_FIXED |
Ingo Molnar | 131484c | 2015-05-28 12:21:47 +0200 | [diff] [blame] | 109 | popfq |
Ingo Molnar | 54ad726 | 2015-06-05 13:02:28 +0200 | [diff] [blame] | 110 | jmp sysenter_flags_fixed |
Ingo Molnar | 4c8cd0c | 2015-06-08 08:33:56 +0200 | [diff] [blame] | 111 | ENDPROC(entry_SYSENTER_compat) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 112 | |
| 113 | /* |
Ingo Molnar | 54ad726 | 2015-06-05 13:02:28 +0200 | [diff] [blame] | 114 | * 32-bit SYSCALL instruction entry. |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 115 | * |
Ingo Molnar | 54ad726 | 2015-06-05 13:02:28 +0200 | [diff] [blame] | 116 | * 32-bit SYSCALL saves rip to rcx, clears rflags.RF, then saves rflags to r11, |
Denys Vlasenko | b87cf63 | 2015-02-26 14:40:32 -0800 | [diff] [blame] | 117 | * then loads new ss, cs, and rip from previously programmed MSRs. |
| 118 | * rflags gets masked by a value from another MSR (so CLD and CLAC |
| 119 | * are not needed). SYSCALL does not save anything on the stack |
| 120 | * and does not change rsp. |
| 121 | * |
| 122 | * Note: rflags saving+masking-with-MSR happens only in Long mode |
Ingo Molnar | 54ad726 | 2015-06-05 13:02:28 +0200 | [diff] [blame] | 123 | * (in legacy 32-bit mode, IF, RF and VM bits are cleared and that's it). |
Denys Vlasenko | b87cf63 | 2015-02-26 14:40:32 -0800 | [diff] [blame] | 124 | * Don't get confused: rflags saving+masking depends on Long Mode Active bit |
| 125 | * (EFER.LMA=1), NOT on bitness of userspace where SYSCALL executes |
| 126 | * or target CS descriptor's L bit (SYSCALL does not read segment descriptors). |
| 127 | * |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 128 | * Arguments: |
Denys Vlasenko | b87cf63 | 2015-02-26 14:40:32 -0800 | [diff] [blame] | 129 | * eax system call number |
| 130 | * ecx return address |
| 131 | * ebx arg1 |
| 132 | * ebp arg2 (note: not saved in the stack frame, should not be touched) |
| 133 | * edx arg3 |
| 134 | * esi arg4 |
| 135 | * edi arg5 |
| 136 | * esp user stack |
| 137 | * 0(%esp) arg6 |
| 138 | * |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 139 | * This is purely a fast path. For anything complicated we use the int 0x80 |
Denys Vlasenko | b87cf63 | 2015-02-26 14:40:32 -0800 | [diff] [blame] | 140 | * path below. We set up a complete hardware stack frame to share code |
| 141 | * with the int 0x80 path. |
| 142 | */ |
Ingo Molnar | 2cd2355 | 2015-06-08 08:28:07 +0200 | [diff] [blame] | 143 | ENTRY(entry_SYSCALL_compat) |
Denys Vlasenko | a232e3d | 2015-03-27 11:36:20 +0100 | [diff] [blame] | 144 | /* |
| 145 | * Interrupts are off on entry. |
| 146 | * We do not frame this tiny irq-off block with TRACE_IRQS_OFF/ON, |
| 147 | * it is too small to ever cause noticeable irq latency. |
| 148 | */ |
Jeremy Fitzhardinge | 457da70 | 2008-06-26 07:28:51 -0700 | [diff] [blame] | 149 | SWAPGS_UNSAFE_STACK |
Andy Lutomirski | e62a254 | 2015-10-05 17:48:02 -0700 | [diff] [blame] | 150 | |
| 151 | /* Temporary: SYSCALL32 is disabled. */ |
| 152 | movl $-ENOSYS, %eax |
| 153 | USERGS_SYSRET32 |
| 154 | |
Ingo Molnar | 54ad726 | 2015-06-05 13:02:28 +0200 | [diff] [blame] | 155 | movl %esp, %r8d |
| 156 | movq PER_CPU_VAR(cpu_current_top_of_stack), %rsp |
Jeremy Fitzhardinge | 6680415 | 2008-06-25 00:19:29 -0400 | [diff] [blame] | 157 | ENABLE_INTERRUPTS(CLBR_NONE) |
Denys Vlasenko | a232e3d | 2015-03-27 11:36:20 +0100 | [diff] [blame] | 158 | |
Denys Vlasenko | 4ee8ec1 | 2015-03-27 11:36:21 +0100 | [diff] [blame] | 159 | /* Zero-extending 32-bit regs, do not remove */ |
Ingo Molnar | 54ad726 | 2015-06-05 13:02:28 +0200 | [diff] [blame] | 160 | movl %eax, %eax |
Denys Vlasenko | 4ee8ec1 | 2015-03-27 11:36:21 +0100 | [diff] [blame] | 161 | |
Denys Vlasenko | 4c9c0e9 | 2015-03-31 19:00:04 +0200 | [diff] [blame] | 162 | /* Construct struct pt_regs on stack */ |
Ingo Molnar | 131484c | 2015-05-28 12:21:47 +0200 | [diff] [blame] | 163 | pushq $__USER32_DS /* pt_regs->ss */ |
| 164 | pushq %r8 /* pt_regs->sp */ |
| 165 | pushq %r11 /* pt_regs->flags */ |
| 166 | pushq $__USER32_CS /* pt_regs->cs */ |
| 167 | pushq %rcx /* pt_regs->ip */ |
| 168 | pushq %rax /* pt_regs->orig_ax */ |
| 169 | pushq %rdi /* pt_regs->di */ |
| 170 | pushq %rsi /* pt_regs->si */ |
| 171 | pushq %rdx /* pt_regs->dx */ |
| 172 | pushq %rbp /* pt_regs->cx */ |
Ingo Molnar | 54ad726 | 2015-06-05 13:02:28 +0200 | [diff] [blame] | 173 | movl %ebp, %ecx |
Ingo Molnar | 131484c | 2015-05-28 12:21:47 +0200 | [diff] [blame] | 174 | pushq $-ENOSYS /* pt_regs->ax */ |
Ingo Molnar | 54ad726 | 2015-06-05 13:02:28 +0200 | [diff] [blame] | 175 | sub $(10*8), %rsp /* pt_regs->r8-11, bp, bx, r12-15 not saved */ |
Denys Vlasenko | 4c9c0e9 | 2015-03-31 19:00:04 +0200 | [diff] [blame] | 176 | |
Andy Lutomirski | 2ec6797 | 2015-10-05 17:48:04 -0700 | [diff] [blame] | 177 | /* Unreachable. */ |
| 178 | ud2 |
Ingo Molnar | 2cd2355 | 2015-06-08 08:28:07 +0200 | [diff] [blame] | 179 | END(entry_SYSCALL_compat) |
Ingo Molnar | 54ad726 | 2015-06-05 13:02:28 +0200 | [diff] [blame] | 180 | |
Denys Vlasenko | b87cf63 | 2015-02-26 14:40:32 -0800 | [diff] [blame] | 181 | /* |
| 182 | * Emulated IA32 system calls via int 0x80. |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 183 | * |
Denys Vlasenko | b87cf63 | 2015-02-26 14:40:32 -0800 | [diff] [blame] | 184 | * Arguments: |
| 185 | * eax system call number |
| 186 | * ebx arg1 |
| 187 | * ecx arg2 |
| 188 | * edx arg3 |
| 189 | * esi arg4 |
| 190 | * edi arg5 |
| 191 | * ebp arg6 (note: not saved in the stack frame, should not be touched) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 192 | * |
| 193 | * Notes: |
Denys Vlasenko | b87cf63 | 2015-02-26 14:40:32 -0800 | [diff] [blame] | 194 | * Uses the same stack frame as the x86-64 version. |
| 195 | * All registers except eax must be saved (but ptrace may violate that). |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 196 | * Arguments are zero extended. For system calls that want sign extension and |
| 197 | * take long arguments a wrapper is needed. Most calls can just be called |
| 198 | * directly. |
Denys Vlasenko | b87cf63 | 2015-02-26 14:40:32 -0800 | [diff] [blame] | 199 | * Assumes it is only called from user space and entered with interrupts off. |
| 200 | */ |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 201 | |
Ingo Molnar | 2cd2355 | 2015-06-08 08:28:07 +0200 | [diff] [blame] | 202 | ENTRY(entry_INT80_compat) |
Denys Vlasenko | a232e3d | 2015-03-27 11:36:20 +0100 | [diff] [blame] | 203 | /* |
| 204 | * Interrupts are off on entry. |
| 205 | * We do not frame this tiny irq-off block with TRACE_IRQS_OFF/ON, |
| 206 | * it is too small to ever cause noticeable irq latency. |
| 207 | */ |
Jeremy Fitzhardinge | 360c044 | 2008-07-08 15:06:28 -0700 | [diff] [blame] | 208 | PARAVIRT_ADJUST_EXCEPTION_FRAME |
Jeremy Fitzhardinge | 6680415 | 2008-06-25 00:19:29 -0400 | [diff] [blame] | 209 | SWAPGS |
Jeremy Fitzhardinge | 6680415 | 2008-06-25 00:19:29 -0400 | [diff] [blame] | 210 | ENABLE_INTERRUPTS(CLBR_NONE) |
Denys Vlasenko | a232e3d | 2015-03-27 11:36:20 +0100 | [diff] [blame] | 211 | |
Denys Vlasenko | 4ee8ec1 | 2015-03-27 11:36:21 +0100 | [diff] [blame] | 212 | /* Zero-extending 32-bit regs, do not remove */ |
Ingo Molnar | 54ad726 | 2015-06-05 13:02:28 +0200 | [diff] [blame] | 213 | movl %eax, %eax |
Denys Vlasenko | 4ee8ec1 | 2015-03-27 11:36:21 +0100 | [diff] [blame] | 214 | |
Denys Vlasenko | 4c9c0e9 | 2015-03-31 19:00:04 +0200 | [diff] [blame] | 215 | /* Construct struct pt_regs on stack (iret frame is already on stack) */ |
Ingo Molnar | 131484c | 2015-05-28 12:21:47 +0200 | [diff] [blame] | 216 | pushq %rax /* pt_regs->orig_ax */ |
| 217 | pushq %rdi /* pt_regs->di */ |
| 218 | pushq %rsi /* pt_regs->si */ |
| 219 | pushq %rdx /* pt_regs->dx */ |
| 220 | pushq %rcx /* pt_regs->cx */ |
| 221 | pushq $-ENOSYS /* pt_regs->ax */ |
Andy Lutomirski | 8169aff | 2015-10-05 17:48:05 -0700 | [diff] [blame^] | 222 | xorq %r8,%r8 |
| 223 | pushq %r8 /* pt_regs->r8 = 0 */ |
| 224 | pushq %r8 /* pt_regs->r9 = 0 */ |
| 225 | pushq %r8 /* pt_regs->r10 = 0 */ |
| 226 | pushq %r8 /* pt_regs->r11 = 0 */ |
| 227 | pushq %rbx /* pt_regs->rbx */ |
| 228 | pushq %rbp /* pt_regs->rbp */ |
| 229 | pushq %r12 /* pt_regs->r12 */ |
| 230 | pushq %r13 /* pt_regs->r13 */ |
| 231 | pushq %r14 /* pt_regs->r14 */ |
| 232 | pushq %r15 /* pt_regs->r15 */ |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 233 | cld |
Denys Vlasenko | 4c9c0e9 | 2015-03-31 19:00:04 +0200 | [diff] [blame] | 234 | |
Ingo Molnar | 54ad726 | 2015-06-05 13:02:28 +0200 | [diff] [blame] | 235 | orl $TS_COMPAT, ASM_THREAD_INFO(TI_status, %rsp, SIZEOF_PTREGS) |
| 236 | testl $_TIF_WORK_SYSCALL_ENTRY, ASM_THREAD_INFO(TI_flags, %rsp, SIZEOF_PTREGS) |
| 237 | jnz ia32_tracesys |
| 238 | |
Roland McGrath | c09249f | 2009-02-06 18:15:18 -0800 | [diff] [blame] | 239 | ia32_do_call: |
Ingo Molnar | 54ad726 | 2015-06-05 13:02:28 +0200 | [diff] [blame] | 240 | /* 32-bit syscall -> 64-bit C ABI argument conversion */ |
| 241 | movl %edi, %r8d /* arg5 */ |
| 242 | movl %ebp, %r9d /* arg6 */ |
| 243 | xchg %ecx, %esi /* rsi:arg2, rcx:arg4 */ |
| 244 | movl %ebx, %edi /* arg1 */ |
| 245 | movl %edx, %edx /* arg3 (zero extension) */ |
| 246 | cmpq $(IA32_NR_syscalls-1), %rax |
Denys Vlasenko | 3f5159a | 2015-04-21 18:03:14 +0200 | [diff] [blame] | 247 | ja 1f |
Ingo Molnar | 54ad726 | 2015-06-05 13:02:28 +0200 | [diff] [blame] | 248 | |
Denys Vlasenko | eb47854 | 2015-06-07 20:24:30 +0200 | [diff] [blame] | 249 | call *ia32_sys_call_table(, %rax, 8) |
Ingo Molnar | 54ad726 | 2015-06-05 13:02:28 +0200 | [diff] [blame] | 250 | movq %rax, RAX(%rsp) |
Denys Vlasenko | 3f5159a | 2015-04-21 18:03:14 +0200 | [diff] [blame] | 251 | 1: |
Andy Lutomirski | 8169aff | 2015-10-05 17:48:05 -0700 | [diff] [blame^] | 252 | RESTORE_EXTRA_REGS |
Ingo Molnar | 54ad726 | 2015-06-05 13:02:28 +0200 | [diff] [blame] | 253 | jmp int_ret_from_sys_call |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 254 | |
Denys Vlasenko | 76f5df4 | 2015-02-26 14:40:27 -0800 | [diff] [blame] | 255 | ia32_tracesys: |
Ingo Molnar | 54ad726 | 2015-06-05 13:02:28 +0200 | [diff] [blame] | 256 | movq %rsp, %rdi /* &pt_regs -> arg1 */ |
| 257 | call syscall_trace_enter |
Denys Vlasenko | 73cbf68 | 2015-06-02 21:04:02 +0200 | [diff] [blame] | 258 | /* |
| 259 | * Reload arg registers from stack in case ptrace changed them. |
| 260 | * Don't reload %eax because syscall_trace_enter() returned |
| 261 | * the %rax value we should see. But do truncate it to 32 bits. |
| 262 | * If it's -1 to make us punt the syscall, then (u32)-1 is still |
| 263 | * an appropriately invalid value. |
| 264 | */ |
| 265 | movl RCX(%rsp), %ecx |
| 266 | movl RDX(%rsp), %edx |
| 267 | movl RSI(%rsp), %esi |
| 268 | movl RDI(%rsp), %edi |
Ingo Molnar | 54ad726 | 2015-06-05 13:02:28 +0200 | [diff] [blame] | 269 | movl %eax, %eax /* zero extension */ |
Ingo Molnar | 54ad726 | 2015-06-05 13:02:28 +0200 | [diff] [blame] | 270 | jmp ia32_do_call |
Ingo Molnar | 2cd2355 | 2015-06-08 08:28:07 +0200 | [diff] [blame] | 271 | END(entry_INT80_compat) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 272 | |
Jan Beulich | f6b2bc8 | 2011-11-29 11:24:10 +0000 | [diff] [blame] | 273 | ALIGN |
Al Viro | 1d4b4b2 | 2012-10-22 22:34:11 -0400 | [diff] [blame] | 274 | GLOBAL(stub32_clone) |
Denys Vlasenko | 5cdc683 | 2015-06-03 15:58:49 +0200 | [diff] [blame] | 275 | /* |
Denys Vlasenko | 7a5a982 | 2015-06-03 15:58:50 +0200 | [diff] [blame] | 276 | * The 32-bit clone ABI is: clone(..., int tls_val, int *child_tidptr). |
| 277 | * The 64-bit clone ABI is: clone(..., int *child_tidptr, int tls_val). |
| 278 | * |
| 279 | * The native 64-bit kernel's sys_clone() implements the latter, |
| 280 | * so we need to swap arguments here before calling it: |
Denys Vlasenko | 5cdc683 | 2015-06-03 15:58:49 +0200 | [diff] [blame] | 281 | */ |
Denys Vlasenko | 7a5a982 | 2015-06-03 15:58:50 +0200 | [diff] [blame] | 282 | xchg %r8, %rcx |
Andy Lutomirski | 8169aff | 2015-10-05 17:48:05 -0700 | [diff] [blame^] | 283 | jmp sys_clone |