Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1 | /* |
| 2 | * This file is subject to the terms and conditions of the GNU General Public |
| 3 | * License. See the file "COPYING" in the main directory of this archive |
| 4 | * for more details. |
| 5 | * |
| 6 | * Copyright (C) 1994 - 1999, 2000 by Ralf Baechle and others. |
Ralf Baechle | 40ac5d4 | 2006-02-08 13:38:18 +0000 | [diff] [blame] | 7 | * Copyright (C) 2005, 2006 by Ralf Baechle (ralf@linux-mips.org) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 8 | * Copyright (C) 1999, 2000 Silicon Graphics, Inc. |
| 9 | * Copyright (C) 2004 Thiemo Seufer |
Leonid Yegoshin | 34c2f66 | 2013-03-25 13:18:07 -0500 | [diff] [blame] | 10 | * Copyright (C) 2013 Imagination Technologies Ltd. |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 11 | */ |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 12 | #include <linux/errno.h> |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 13 | #include <linux/sched.h> |
Ralf Baechle | 7bcf771 | 2007-10-11 23:46:09 +0100 | [diff] [blame] | 14 | #include <linux/tick.h> |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 15 | #include <linux/kernel.h> |
| 16 | #include <linux/mm.h> |
| 17 | #include <linux/stddef.h> |
| 18 | #include <linux/unistd.h> |
Paul Gortmaker | cae39d1 | 2011-07-28 18:46:31 -0400 | [diff] [blame] | 19 | #include <linux/export.h> |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 20 | #include <linux/ptrace.h> |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 21 | #include <linux/mman.h> |
| 22 | #include <linux/personality.h> |
| 23 | #include <linux/sys.h> |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 24 | #include <linux/init.h> |
| 25 | #include <linux/completion.h> |
Atsushi Nemoto | 6307751 | 2006-02-08 01:48:03 +0900 | [diff] [blame] | 26 | #include <linux/kallsyms.h> |
Franck Bui-Huu | 9410910 | 2007-07-19 14:04:21 +0200 | [diff] [blame] | 27 | #include <linux/random.h> |
Paul Burton | 9791554 | 2015-01-08 12:17:37 +0000 | [diff] [blame] | 28 | #include <linux/prctl.h> |
Paul Burton | dc9e795 | 2018-06-22 10:55:46 -0700 | [diff] [blame] | 29 | #include <linux/nmi.h> |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 30 | |
Franck Bui-Huu | 9410910 | 2007-07-19 14:04:21 +0200 | [diff] [blame] | 31 | #include <asm/asm.h> |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 32 | #include <asm/bootinfo.h> |
| 33 | #include <asm/cpu.h> |
Paul Burton | 432c6ba | 2016-07-08 11:06:19 +0100 | [diff] [blame] | 34 | #include <asm/dsemul.h> |
Ralf Baechle | e50c0a8 | 2005-05-31 11:49:19 +0000 | [diff] [blame] | 35 | #include <asm/dsp.h> |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 36 | #include <asm/fpu.h> |
Matt Redfearn | 86b54e4 | 2016-12-19 14:20:57 +0000 | [diff] [blame] | 37 | #include <asm/irq.h> |
Paul Burton | 1db1af8 | 2014-01-27 15:23:11 +0000 | [diff] [blame] | 38 | #include <asm/msa.h> |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 39 | #include <asm/pgtable.h> |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 40 | #include <asm/mipsregs.h> |
| 41 | #include <asm/processor.h> |
Alex Smith | 60be939 | 2014-07-23 14:40:15 +0100 | [diff] [blame] | 42 | #include <asm/reg.h> |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 43 | #include <asm/uaccess.h> |
| 44 | #include <asm/io.h> |
| 45 | #include <asm/elf.h> |
| 46 | #include <asm/isadep.h> |
| 47 | #include <asm/inst.h> |
Atsushi Nemoto | 1df0f0f | 2006-09-26 23:44:01 +0900 | [diff] [blame] | 48 | #include <asm/stacktrace.h> |
Eunbong Song | 856839b | 2014-10-22 06:39:56 +0000 | [diff] [blame] | 49 | #include <asm/irq_regs.h> |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 50 | |
Ralf Baechle | 1b2bc75 | 2009-06-23 10:00:31 +0100 | [diff] [blame] | 51 | #ifdef CONFIG_HOTPLUG_CPU |
Thomas Gleixner | cdbedc6 | 2013-03-21 22:49:52 +0100 | [diff] [blame] | 52 | void arch_cpu_idle_dead(void) |
| 53 | { |
Matt Redfearn | d99db83 | 2016-11-04 09:28:56 +0000 | [diff] [blame] | 54 | play_dead(); |
Thomas Gleixner | cdbedc6 | 2013-03-21 22:49:52 +0100 | [diff] [blame] | 55 | } |
Ralf Baechle | 1b2bc75 | 2009-06-23 10:00:31 +0100 | [diff] [blame] | 56 | #endif |
Thomas Gleixner | cdbedc6 | 2013-03-21 22:49:52 +0100 | [diff] [blame] | 57 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 58 | asmlinkage void ret_from_fork(void); |
Al Viro | 8f54bca | 2012-10-09 16:27:45 -0400 | [diff] [blame] | 59 | asmlinkage void ret_from_kernel_thread(void); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 60 | |
| 61 | void start_thread(struct pt_regs * regs, unsigned long pc, unsigned long sp) |
| 62 | { |
| 63 | unsigned long status; |
| 64 | |
| 65 | /* New thread loses kernel privileges. */ |
Chris Dearman | bbaf238 | 2007-12-13 22:42:19 +0000 | [diff] [blame] | 66 | status = regs->cp0_status & ~(ST0_CU0|ST0_CU1|ST0_FR|KU_MASK); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 67 | status |= KU_USER; |
| 68 | regs->cp0_status = status; |
James Hogan | 76e5846 | 2016-02-01 13:50:36 +0000 | [diff] [blame] | 69 | lose_fpu(0); |
Paul Burton | 1db1af8 | 2014-01-27 15:23:11 +0000 | [diff] [blame] | 70 | clear_thread_flag(TIF_MSA_CTX_LIVE); |
James Hogan | 76e5846 | 2016-02-01 13:50:36 +0000 | [diff] [blame] | 71 | clear_used_math(); |
Paul Burton | 432c6ba | 2016-07-08 11:06:19 +0100 | [diff] [blame] | 72 | atomic_set(¤t->thread.bd_emu_frame, BD_EMUFRAME_NONE); |
James Hogan | 76e5846 | 2016-02-01 13:50:36 +0000 | [diff] [blame] | 73 | init_dsp(); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 74 | regs->cp0_epc = pc; |
| 75 | regs->regs[29] = sp; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 76 | } |
| 77 | |
Paul Burton | 432c6ba | 2016-07-08 11:06:19 +0100 | [diff] [blame] | 78 | void exit_thread(struct task_struct *tsk) |
| 79 | { |
| 80 | /* |
| 81 | * User threads may have allocated a delay slot emulation frame. |
| 82 | * If so, clean up that allocation. |
| 83 | */ |
| 84 | if (!(current->flags & PF_KTHREAD)) |
| 85 | dsemul_thread_cleanup(tsk); |
| 86 | } |
| 87 | |
James Hogan | 39148e9 | 2015-01-19 10:30:54 +0000 | [diff] [blame] | 88 | int arch_dup_task_struct(struct task_struct *dst, struct task_struct *src) |
| 89 | { |
| 90 | /* |
| 91 | * Save any process state which is live in hardware registers to the |
| 92 | * parent context prior to duplication. This prevents the new child |
| 93 | * state becoming stale if the parent is preempted before copy_thread() |
| 94 | * gets a chance to save the parent's live hardware registers to the |
| 95 | * child context. |
| 96 | */ |
| 97 | preempt_disable(); |
| 98 | |
| 99 | if (is_msa_enabled()) |
| 100 | save_msa(current); |
| 101 | else if (is_fpu_owner()) |
| 102 | _save_fp(current); |
| 103 | |
| 104 | save_dsp(current); |
| 105 | |
| 106 | preempt_enable(); |
| 107 | |
| 108 | *dst = *src; |
| 109 | return 0; |
| 110 | } |
| 111 | |
Alex Dowad | e2c5aaa | 2015-03-13 20:14:41 +0200 | [diff] [blame] | 112 | /* |
| 113 | * Copy architecture-specific thread state |
| 114 | */ |
Alexey Dobriyan | 6f2c55b | 2009-04-02 16:56:59 -0700 | [diff] [blame] | 115 | int copy_thread(unsigned long clone_flags, unsigned long usp, |
Alex Dowad | e2c5aaa | 2015-03-13 20:14:41 +0200 | [diff] [blame] | 116 | unsigned long kthread_arg, struct task_struct *p) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 117 | { |
Al Viro | 75bb07e | 2006-01-12 01:06:08 -0800 | [diff] [blame] | 118 | struct thread_info *ti = task_thread_info(p); |
Al Viro | afa86fc | 2012-10-22 22:51:14 -0400 | [diff] [blame] | 119 | struct pt_regs *childregs, *regs = current_pt_regs(); |
David Daney | 484889f | 2009-07-08 10:07:50 -0700 | [diff] [blame] | 120 | unsigned long childksp; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 121 | |
Al Viro | 75bb07e | 2006-01-12 01:06:08 -0800 | [diff] [blame] | 122 | childksp = (unsigned long)task_stack_page(p) + THREAD_SIZE - 32; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 123 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 124 | /* set up new TSS. */ |
| 125 | childregs = (struct pt_regs *) childksp - 1; |
David Daney | 484889f | 2009-07-08 10:07:50 -0700 | [diff] [blame] | 126 | /* Put the stack after the struct pt_regs. */ |
| 127 | childksp = (unsigned long) childregs; |
Al Viro | 8f54bca | 2012-10-09 16:27:45 -0400 | [diff] [blame] | 128 | p->thread.cp0_status = read_c0_status() & ~(ST0_CU2|ST0_CU1); |
| 129 | if (unlikely(p->flags & PF_KTHREAD)) { |
Alex Dowad | e2c5aaa | 2015-03-13 20:14:41 +0200 | [diff] [blame] | 130 | /* kernel thread */ |
Al Viro | 8f54bca | 2012-10-09 16:27:45 -0400 | [diff] [blame] | 131 | unsigned long status = p->thread.cp0_status; |
| 132 | memset(childregs, 0, sizeof(struct pt_regs)); |
| 133 | ti->addr_limit = KERNEL_DS; |
| 134 | p->thread.reg16 = usp; /* fn */ |
Alex Dowad | e2c5aaa | 2015-03-13 20:14:41 +0200 | [diff] [blame] | 135 | p->thread.reg17 = kthread_arg; |
Al Viro | 8f54bca | 2012-10-09 16:27:45 -0400 | [diff] [blame] | 136 | p->thread.reg29 = childksp; |
| 137 | p->thread.reg31 = (unsigned long) ret_from_kernel_thread; |
| 138 | #if defined(CONFIG_CPU_R3000) || defined(CONFIG_CPU_TX39XX) |
| 139 | status = (status & ~(ST0_KUP | ST0_IEP | ST0_IEC)) | |
| 140 | ((status & (ST0_KUC | ST0_IEC)) << 2); |
| 141 | #else |
| 142 | status |= ST0_EXL; |
| 143 | #endif |
| 144 | childregs->cp0_status = status; |
| 145 | return 0; |
| 146 | } |
Alex Dowad | e2c5aaa | 2015-03-13 20:14:41 +0200 | [diff] [blame] | 147 | |
| 148 | /* user thread */ |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 149 | *childregs = *regs; |
Ralf Baechle | 7034228 | 2013-01-22 12:59:30 +0100 | [diff] [blame] | 150 | childregs->regs[7] = 0; /* Clear error flag */ |
| 151 | childregs->regs[2] = 0; /* Child gets zero as return value */ |
Al Viro | 64b3122 | 2012-12-27 11:52:32 -0500 | [diff] [blame] | 152 | if (usp) |
| 153 | childregs->regs[29] = usp; |
Al Viro | 8f54bca | 2012-10-09 16:27:45 -0400 | [diff] [blame] | 154 | ti->addr_limit = USER_DS; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 155 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 156 | p->thread.reg29 = (unsigned long) childregs; |
| 157 | p->thread.reg31 = (unsigned long) ret_from_fork; |
| 158 | |
| 159 | /* |
| 160 | * New tasks lose permission to use the fpu. This accelerates context |
| 161 | * switching for most programs since they don't use the fpu. |
| 162 | */ |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 163 | childregs->cp0_status &= ~(ST0_CU2|ST0_CU1); |
Kevin D. Kissell | 9cc1236 | 2008-09-09 21:33:36 +0200 | [diff] [blame] | 164 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 165 | clear_tsk_thread_flag(p, TIF_USEDFPU); |
Paul Burton | 7daef8f | 2014-07-11 16:47:05 +0100 | [diff] [blame] | 166 | clear_tsk_thread_flag(p, TIF_USEDMSA); |
| 167 | clear_tsk_thread_flag(p, TIF_MSA_CTX_LIVE); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 168 | |
Ralf Baechle | f088fc8 | 2006-04-05 09:45:47 +0100 | [diff] [blame] | 169 | #ifdef CONFIG_MIPS_MT_FPAFF |
Ralf Baechle | 6657fe0 | 2008-09-09 15:19:10 +0200 | [diff] [blame] | 170 | clear_tsk_thread_flag(p, TIF_FPUBOUND); |
Ralf Baechle | f088fc8 | 2006-04-05 09:45:47 +0100 | [diff] [blame] | 171 | #endif /* CONFIG_MIPS_MT_FPAFF */ |
| 172 | |
Paul Burton | 432c6ba | 2016-07-08 11:06:19 +0100 | [diff] [blame] | 173 | atomic_set(&p->thread.bd_emu_frame, BD_EMUFRAME_NONE); |
| 174 | |
Ralf Baechle | 3c37026 | 2005-04-13 17:43:59 +0000 | [diff] [blame] | 175 | if (clone_flags & CLONE_SETTLS) |
| 176 | ti->tp_value = regs->regs[7]; |
| 177 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 178 | return 0; |
| 179 | } |
| 180 | |
Gregory Fong | 36ecafc | 2013-06-12 17:08:54 +0000 | [diff] [blame] | 181 | #ifdef CONFIG_CC_STACKPROTECTOR |
| 182 | #include <linux/stackprotector.h> |
| 183 | unsigned long __stack_chk_guard __read_mostly; |
| 184 | EXPORT_SYMBOL(__stack_chk_guard); |
| 185 | #endif |
| 186 | |
Franck Bui-Huu | b594318 | 2006-08-18 16:18:09 +0200 | [diff] [blame] | 187 | struct mips_frame_info { |
| 188 | void *func; |
| 189 | unsigned long func_size; |
| 190 | int frame_size; |
| 191 | int pc_offset; |
| 192 | }; |
Thiemo Seufer | dc953df | 2005-02-21 10:55:16 +0000 | [diff] [blame] | 193 | |
Tony Wu | 5000653 | 2013-05-12 15:05:34 +0000 | [diff] [blame] | 194 | #define J_TARGET(pc,target) \ |
| 195 | (((unsigned long)(pc) & 0xf0000000) | ((target) << 2)) |
| 196 | |
Paul Burton | 209ad19 | 2016-11-07 15:07:06 +0000 | [diff] [blame] | 197 | static inline int is_ra_save_ins(union mips_instruction *ip, int *poff) |
Franck Bui-Huu | c0efbb6 | 2006-08-03 09:29:15 +0200 | [diff] [blame] | 198 | { |
Leonid Yegoshin | 34c2f66 | 2013-03-25 13:18:07 -0500 | [diff] [blame] | 199 | #ifdef CONFIG_CPU_MICROMIPS |
Leonid Yegoshin | 34c2f66 | 2013-03-25 13:18:07 -0500 | [diff] [blame] | 200 | /* |
| 201 | * swsp ra,offset |
| 202 | * swm16 reglist,offset(sp) |
| 203 | * swm32 reglist,offset(sp) |
| 204 | * sw32 ra,offset(sp) |
| 205 | * jradiussp - NOT SUPPORTED |
| 206 | * |
| 207 | * microMIPS is way more fun... |
| 208 | */ |
Paul Burton | ce449cb | 2016-11-07 15:07:03 +0000 | [diff] [blame] | 209 | if (mm_insn_16bit(ip->halfword[1])) { |
Paul Burton | 209ad19 | 2016-11-07 15:07:06 +0000 | [diff] [blame] | 210 | switch (ip->mm16_r5_format.opcode) { |
| 211 | case mm_swsp16_op: |
| 212 | if (ip->mm16_r5_format.rt != 31) |
| 213 | return 0; |
| 214 | |
Matt Redfearn | 416ca41 | 2017-08-08 13:22:33 +0100 | [diff] [blame] | 215 | *poff = ip->mm16_r5_format.imm; |
Paul Burton | 209ad19 | 2016-11-07 15:07:06 +0000 | [diff] [blame] | 216 | *poff = (*poff << 2) / sizeof(ulong); |
| 217 | return 1; |
| 218 | |
| 219 | case mm_pool16c_op: |
| 220 | switch (ip->mm16_m_format.func) { |
| 221 | case mm_swm16_op: |
| 222 | *poff = ip->mm16_m_format.imm; |
| 223 | *poff += 1 + ip->mm16_m_format.rlist; |
| 224 | *poff = (*poff << 2) / sizeof(ulong); |
| 225 | return 1; |
| 226 | |
| 227 | default: |
| 228 | return 0; |
| 229 | } |
| 230 | |
| 231 | default: |
| 232 | return 0; |
| 233 | } |
Leonid Yegoshin | 34c2f66 | 2013-03-25 13:18:07 -0500 | [diff] [blame] | 234 | } |
Paul Burton | 209ad19 | 2016-11-07 15:07:06 +0000 | [diff] [blame] | 235 | |
| 236 | switch (ip->i_format.opcode) { |
| 237 | case mm_sw32_op: |
| 238 | if (ip->i_format.rs != 29) |
| 239 | return 0; |
| 240 | if (ip->i_format.rt != 31) |
| 241 | return 0; |
| 242 | |
| 243 | *poff = ip->i_format.simmediate / sizeof(ulong); |
| 244 | return 1; |
| 245 | |
| 246 | case mm_pool32b_op: |
| 247 | switch (ip->mm_m_format.func) { |
| 248 | case mm_swm32_func: |
| 249 | if (ip->mm_m_format.rd < 0x10) |
| 250 | return 0; |
| 251 | if (ip->mm_m_format.base != 29) |
| 252 | return 0; |
| 253 | |
| 254 | *poff = ip->mm_m_format.simmediate; |
| 255 | *poff += (ip->mm_m_format.rd & 0xf) * sizeof(u32); |
| 256 | *poff /= sizeof(ulong); |
| 257 | return 1; |
| 258 | default: |
| 259 | return 0; |
| 260 | } |
| 261 | |
| 262 | default: |
| 263 | return 0; |
Leonid Yegoshin | 34c2f66 | 2013-03-25 13:18:07 -0500 | [diff] [blame] | 264 | } |
| 265 | #else |
Franck Bui-Huu | c0efbb6 | 2006-08-03 09:29:15 +0200 | [diff] [blame] | 266 | /* sw / sd $ra, offset($sp) */ |
Paul Burton | 209ad19 | 2016-11-07 15:07:06 +0000 | [diff] [blame] | 267 | if ((ip->i_format.opcode == sw_op || ip->i_format.opcode == sd_op) && |
| 268 | ip->i_format.rs == 29 && ip->i_format.rt == 31) { |
| 269 | *poff = ip->i_format.simmediate / sizeof(ulong); |
| 270 | return 1; |
| 271 | } |
| 272 | |
| 273 | return 0; |
Leonid Yegoshin | 34c2f66 | 2013-03-25 13:18:07 -0500 | [diff] [blame] | 274 | #endif |
Franck Bui-Huu | c0efbb6 | 2006-08-03 09:29:15 +0200 | [diff] [blame] | 275 | } |
| 276 | |
Tony Wu | e7438c4 | 2013-05-12 15:04:29 +0000 | [diff] [blame] | 277 | static inline int is_jump_ins(union mips_instruction *ip) |
Franck Bui-Huu | c0efbb6 | 2006-08-03 09:29:15 +0200 | [diff] [blame] | 278 | { |
Leonid Yegoshin | 34c2f66 | 2013-03-25 13:18:07 -0500 | [diff] [blame] | 279 | #ifdef CONFIG_CPU_MICROMIPS |
| 280 | /* |
| 281 | * jr16,jrc,jalr16,jalr16 |
| 282 | * jal |
| 283 | * jalr/jr,jalr.hb/jr.hb,jalrs,jalrs.hb |
| 284 | * jraddiusp - NOT SUPPORTED |
| 285 | * |
| 286 | * microMIPS is kind of more fun... |
| 287 | */ |
Paul Burton | b14e085 | 2016-11-07 15:07:05 +0000 | [diff] [blame] | 288 | if (mm_insn_16bit(ip->halfword[1])) { |
| 289 | if ((ip->mm16_r5_format.opcode == mm_pool16c_op && |
| 290 | (ip->mm16_r5_format.rt & mm_jr16_op) == mm_jr16_op)) |
| 291 | return 1; |
| 292 | return 0; |
| 293 | } |
| 294 | |
Paul Burton | 8d06cbd | 2016-11-07 15:07:07 +0000 | [diff] [blame] | 295 | if (ip->j_format.opcode == mm_j32_op) |
| 296 | return 1; |
Paul Burton | b14e085 | 2016-11-07 15:07:05 +0000 | [diff] [blame] | 297 | if (ip->j_format.opcode == mm_jal32_op) |
Leonid Yegoshin | 34c2f66 | 2013-03-25 13:18:07 -0500 | [diff] [blame] | 298 | return 1; |
| 299 | if (ip->r_format.opcode != mm_pool32a_op || |
| 300 | ip->r_format.func != mm_pool32axf_op) |
| 301 | return 0; |
Ralf Baechle | 635c9907 | 2014-10-21 14:12:49 +0200 | [diff] [blame] | 302 | return ((ip->u_format.uimmediate >> 6) & mm_jalr_op) == mm_jalr_op; |
Leonid Yegoshin | 34c2f66 | 2013-03-25 13:18:07 -0500 | [diff] [blame] | 303 | #else |
Tony Wu | e7438c4 | 2013-05-12 15:04:29 +0000 | [diff] [blame] | 304 | if (ip->j_format.opcode == j_op) |
| 305 | return 1; |
Franck Bui-Huu | c0efbb6 | 2006-08-03 09:29:15 +0200 | [diff] [blame] | 306 | if (ip->j_format.opcode == jal_op) |
| 307 | return 1; |
| 308 | if (ip->r_format.opcode != spec_op) |
| 309 | return 0; |
| 310 | return ip->r_format.func == jalr_op || ip->r_format.func == jr_op; |
Leonid Yegoshin | 34c2f66 | 2013-03-25 13:18:07 -0500 | [diff] [blame] | 311 | #endif |
Franck Bui-Huu | c0efbb6 | 2006-08-03 09:29:15 +0200 | [diff] [blame] | 312 | } |
| 313 | |
| 314 | static inline int is_sp_move_ins(union mips_instruction *ip) |
| 315 | { |
Leonid Yegoshin | 34c2f66 | 2013-03-25 13:18:07 -0500 | [diff] [blame] | 316 | #ifdef CONFIG_CPU_MICROMIPS |
| 317 | /* |
| 318 | * addiusp -imm |
| 319 | * addius5 sp,-imm |
| 320 | * addiu32 sp,sp,-imm |
| 321 | * jradiussp - NOT SUPPORTED |
| 322 | * |
| 323 | * microMIPS is not more fun... |
| 324 | */ |
Paul Burton | ce449cb | 2016-11-07 15:07:03 +0000 | [diff] [blame] | 325 | if (mm_insn_16bit(ip->halfword[1])) { |
| 326 | return (ip->mm16_r3_format.opcode == mm_pool16d_op && |
| 327 | ip->mm16_r3_format.simmediate && mm_addiusp_func) || |
| 328 | (ip->mm16_r5_format.opcode == mm_pool16d_op && |
| 329 | ip->mm16_r5_format.rt == 29); |
Leonid Yegoshin | 34c2f66 | 2013-03-25 13:18:07 -0500 | [diff] [blame] | 330 | } |
Paul Burton | ce449cb | 2016-11-07 15:07:03 +0000 | [diff] [blame] | 331 | |
Ralf Baechle | 635c9907 | 2014-10-21 14:12:49 +0200 | [diff] [blame] | 332 | return ip->mm_i_format.opcode == mm_addiu32_op && |
| 333 | ip->mm_i_format.rt == 29 && ip->mm_i_format.rs == 29; |
Leonid Yegoshin | 34c2f66 | 2013-03-25 13:18:07 -0500 | [diff] [blame] | 334 | #else |
Franck Bui-Huu | c0efbb6 | 2006-08-03 09:29:15 +0200 | [diff] [blame] | 335 | /* addiu/daddiu sp,sp,-imm */ |
| 336 | if (ip->i_format.rs != 29 || ip->i_format.rt != 29) |
| 337 | return 0; |
| 338 | if (ip->i_format.opcode == addiu_op || ip->i_format.opcode == daddiu_op) |
| 339 | return 1; |
Leonid Yegoshin | 34c2f66 | 2013-03-25 13:18:07 -0500 | [diff] [blame] | 340 | #endif |
Franck Bui-Huu | c0efbb6 | 2006-08-03 09:29:15 +0200 | [diff] [blame] | 341 | return 0; |
| 342 | } |
| 343 | |
Atsushi Nemoto | f66686f | 2006-07-29 23:27:20 +0900 | [diff] [blame] | 344 | static int get_frame_info(struct mips_frame_info *info) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 345 | { |
Paul Burton | ce449cb | 2016-11-07 15:07:03 +0000 | [diff] [blame] | 346 | bool is_mmips = IS_ENABLED(CONFIG_CPU_MICROMIPS); |
Jun-Ru Chang | a189410 | 2019-01-29 11:56:07 +0800 | [diff] [blame] | 347 | union mips_instruction insn, *ip; |
Paul Burton | b0b4eb5 | 2016-11-07 15:07:04 +0000 | [diff] [blame] | 348 | const unsigned int max_insns = 128; |
Matt Redfearn | 8ca1179 | 2017-08-08 13:22:30 +0100 | [diff] [blame] | 349 | unsigned int last_insn_size = 0; |
Paul Burton | b0b4eb5 | 2016-11-07 15:07:04 +0000 | [diff] [blame] | 350 | unsigned int i; |
Franck Bui-Huu | c0efbb6 | 2006-08-03 09:29:15 +0200 | [diff] [blame] | 351 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 352 | info->pc_offset = -1; |
Atsushi Nemoto | 6307751 | 2006-02-08 01:48:03 +0900 | [diff] [blame] | 353 | info->frame_size = 0; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 354 | |
Paul Burton | d0eae5b | 2016-11-07 15:07:02 +0000 | [diff] [blame] | 355 | ip = (void *)msk_isa16_mode((ulong)info->func); |
Franck Bui-Huu | 29b376f | 2006-08-18 16:18:08 +0200 | [diff] [blame] | 356 | if (!ip) |
| 357 | goto err; |
| 358 | |
Jun-Ru Chang | a189410 | 2019-01-29 11:56:07 +0800 | [diff] [blame] | 359 | for (i = 0; i < max_insns; i++) { |
Matt Redfearn | 8ca1179 | 2017-08-08 13:22:30 +0100 | [diff] [blame] | 360 | ip = (void *)ip + last_insn_size; |
Jun-Ru Chang | a189410 | 2019-01-29 11:56:07 +0800 | [diff] [blame] | 361 | |
Paul Burton | ce449cb | 2016-11-07 15:07:03 +0000 | [diff] [blame] | 362 | if (is_mmips && mm_insn_16bit(ip->halfword[0])) { |
| 363 | insn.halfword[0] = 0; |
| 364 | insn.halfword[1] = ip->halfword[0]; |
Matt Redfearn | 8ca1179 | 2017-08-08 13:22:30 +0100 | [diff] [blame] | 365 | last_insn_size = 2; |
Paul Burton | ce449cb | 2016-11-07 15:07:03 +0000 | [diff] [blame] | 366 | } else if (is_mmips) { |
| 367 | insn.halfword[0] = ip->halfword[1]; |
| 368 | insn.halfword[1] = ip->halfword[0]; |
Matt Redfearn | 8ca1179 | 2017-08-08 13:22:30 +0100 | [diff] [blame] | 369 | last_insn_size = 4; |
Paul Burton | ce449cb | 2016-11-07 15:07:03 +0000 | [diff] [blame] | 370 | } else { |
| 371 | insn.word = ip->word; |
Matt Redfearn | 8ca1179 | 2017-08-08 13:22:30 +0100 | [diff] [blame] | 372 | last_insn_size = 4; |
Paul Burton | ce449cb | 2016-11-07 15:07:03 +0000 | [diff] [blame] | 373 | } |
Franck Bui-Huu | c0efbb6 | 2006-08-03 09:29:15 +0200 | [diff] [blame] | 374 | |
Paul Burton | ce449cb | 2016-11-07 15:07:03 +0000 | [diff] [blame] | 375 | if (is_jump_ins(&insn)) |
Atsushi Nemoto | 6307751 | 2006-02-08 01:48:03 +0900 | [diff] [blame] | 376 | break; |
Paul Burton | ce449cb | 2016-11-07 15:07:03 +0000 | [diff] [blame] | 377 | |
Franck Bui-Huu | 0cceb4a | 2006-08-03 09:29:20 +0200 | [diff] [blame] | 378 | if (!info->frame_size) { |
Paul Burton | ce449cb | 2016-11-07 15:07:03 +0000 | [diff] [blame] | 379 | if (is_sp_move_ins(&insn)) |
Leonid Yegoshin | 34c2f66 | 2013-03-25 13:18:07 -0500 | [diff] [blame] | 380 | { |
| 381 | #ifdef CONFIG_CPU_MICROMIPS |
| 382 | if (mm_insn_16bit(ip->halfword[0])) |
| 383 | { |
| 384 | unsigned short tmp; |
| 385 | |
| 386 | if (ip->halfword[0] & mm_addiusp_func) |
| 387 | { |
| 388 | tmp = (((ip->halfword[0] >> 1) & 0x1ff) << 2); |
| 389 | info->frame_size = -(signed short)(tmp | ((tmp & 0x100) ? 0xfe00 : 0)); |
| 390 | } else { |
| 391 | tmp = (ip->halfword[0] >> 1); |
| 392 | info->frame_size = -(signed short)(tmp & 0xf); |
| 393 | } |
Leonid Yegoshin | 34c2f66 | 2013-03-25 13:18:07 -0500 | [diff] [blame] | 394 | } else |
| 395 | #endif |
Franck Bui-Huu | 0cceb4a | 2006-08-03 09:29:20 +0200 | [diff] [blame] | 396 | info->frame_size = - ip->i_format.simmediate; |
Leonid Yegoshin | 34c2f66 | 2013-03-25 13:18:07 -0500 | [diff] [blame] | 397 | } |
Franck Bui-Huu | 0cceb4a | 2006-08-03 09:29:20 +0200 | [diff] [blame] | 398 | continue; |
Atsushi Nemoto | 6307751 | 2006-02-08 01:48:03 +0900 | [diff] [blame] | 399 | } |
Paul Burton | 209ad19 | 2016-11-07 15:07:06 +0000 | [diff] [blame] | 400 | if (info->pc_offset == -1 && |
| 401 | is_ra_save_ins(&insn, &info->pc_offset)) |
Franck Bui-Huu | 0cceb4a | 2006-08-03 09:29:20 +0200 | [diff] [blame] | 402 | break; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 403 | } |
Atsushi Nemoto | f66686f | 2006-07-29 23:27:20 +0900 | [diff] [blame] | 404 | if (info->frame_size && info->pc_offset >= 0) /* nested */ |
| 405 | return 0; |
| 406 | if (info->pc_offset < 0) /* leaf */ |
| 407 | return 1; |
Andrea Gelmini | a90c59e | 2016-05-21 14:01:27 +0200 | [diff] [blame] | 408 | /* prologue seems bogus... */ |
Franck Bui-Huu | 29b376f | 2006-08-18 16:18:08 +0200 | [diff] [blame] | 409 | err: |
Atsushi Nemoto | f66686f | 2006-07-29 23:27:20 +0900 | [diff] [blame] | 410 | return -1; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 411 | } |
| 412 | |
Franck Bui-Huu | b594318 | 2006-08-18 16:18:09 +0200 | [diff] [blame] | 413 | static struct mips_frame_info schedule_mfi __read_mostly; |
| 414 | |
Tony Wu | 5000653 | 2013-05-12 15:05:34 +0000 | [diff] [blame] | 415 | #ifdef CONFIG_KALLSYMS |
| 416 | static unsigned long get___schedule_addr(void) |
| 417 | { |
| 418 | return kallsyms_lookup_name("__schedule"); |
| 419 | } |
| 420 | #else |
| 421 | static unsigned long get___schedule_addr(void) |
| 422 | { |
| 423 | union mips_instruction *ip = (void *)schedule; |
| 424 | int max_insns = 8; |
| 425 | int i; |
| 426 | |
| 427 | for (i = 0; i < max_insns; i++, ip++) { |
| 428 | if (ip->j_format.opcode == j_op) |
| 429 | return J_TARGET(ip, ip->j_format.target); |
| 430 | } |
| 431 | return 0; |
| 432 | } |
| 433 | #endif |
| 434 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 435 | static int __init frame_info_init(void) |
| 436 | { |
Franck Bui-Huu | b594318 | 2006-08-18 16:18:09 +0200 | [diff] [blame] | 437 | unsigned long size = 0; |
Atsushi Nemoto | 6307751 | 2006-02-08 01:48:03 +0900 | [diff] [blame] | 438 | #ifdef CONFIG_KALLSYMS |
Franck Bui-Huu | b594318 | 2006-08-18 16:18:09 +0200 | [diff] [blame] | 439 | unsigned long ofs; |
Atsushi Nemoto | 6307751 | 2006-02-08 01:48:03 +0900 | [diff] [blame] | 440 | #endif |
Tony Wu | 5000653 | 2013-05-12 15:05:34 +0000 | [diff] [blame] | 441 | unsigned long addr; |
| 442 | |
| 443 | addr = get___schedule_addr(); |
| 444 | if (!addr) |
| 445 | addr = (unsigned long)schedule; |
| 446 | |
| 447 | #ifdef CONFIG_KALLSYMS |
| 448 | kallsyms_lookup_size_offset(addr, &size, &ofs); |
| 449 | #endif |
| 450 | schedule_mfi.func = (void *)addr; |
Franck Bui-Huu | b594318 | 2006-08-18 16:18:09 +0200 | [diff] [blame] | 451 | schedule_mfi.func_size = size; |
| 452 | |
| 453 | get_frame_info(&schedule_mfi); |
Franck Bui-Huu | 6057a79 | 2006-08-03 09:29:18 +0200 | [diff] [blame] | 454 | |
| 455 | /* |
| 456 | * Without schedule() frame info, result given by |
| 457 | * thread_saved_pc() and get_wchan() are not reliable. |
| 458 | */ |
Franck Bui-Huu | b594318 | 2006-08-18 16:18:09 +0200 | [diff] [blame] | 459 | if (schedule_mfi.pc_offset < 0) |
Franck Bui-Huu | 6057a79 | 2006-08-03 09:29:18 +0200 | [diff] [blame] | 460 | printk("Can't analyze schedule() prologue at %p\n", schedule); |
Atsushi Nemoto | 6307751 | 2006-02-08 01:48:03 +0900 | [diff] [blame] | 461 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 462 | return 0; |
| 463 | } |
| 464 | |
| 465 | arch_initcall(frame_info_init); |
| 466 | |
| 467 | /* |
| 468 | * Return saved PC of a blocked thread. |
| 469 | */ |
| 470 | unsigned long thread_saved_pc(struct task_struct *tsk) |
| 471 | { |
| 472 | struct thread_struct *t = &tsk->thread; |
| 473 | |
| 474 | /* New born processes are a special case */ |
| 475 | if (t->reg31 == (unsigned long) ret_from_fork) |
| 476 | return t->reg31; |
Franck Bui-Huu | b594318 | 2006-08-18 16:18:09 +0200 | [diff] [blame] | 477 | if (schedule_mfi.pc_offset < 0) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 478 | return 0; |
Franck Bui-Huu | b594318 | 2006-08-18 16:18:09 +0200 | [diff] [blame] | 479 | return ((unsigned long *)t->reg29)[schedule_mfi.pc_offset]; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 480 | } |
| 481 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 482 | |
Atsushi Nemoto | f66686f | 2006-07-29 23:27:20 +0900 | [diff] [blame] | 483 | #ifdef CONFIG_KALLSYMS |
Daniel Kalmar | 94ea09c | 2011-05-13 08:38:04 -0400 | [diff] [blame] | 484 | /* generic stack unwinding function */ |
| 485 | unsigned long notrace unwind_stack_by_address(unsigned long stack_page, |
| 486 | unsigned long *sp, |
| 487 | unsigned long pc, |
| 488 | unsigned long *ra) |
Atsushi Nemoto | f66686f | 2006-07-29 23:27:20 +0900 | [diff] [blame] | 489 | { |
Matt Redfearn | 3798fd1 | 2017-03-21 14:52:25 +0000 | [diff] [blame] | 490 | unsigned long low, high, irq_stack_high; |
Atsushi Nemoto | f66686f | 2006-07-29 23:27:20 +0900 | [diff] [blame] | 491 | struct mips_frame_info info; |
Atsushi Nemoto | f66686f | 2006-07-29 23:27:20 +0900 | [diff] [blame] | 492 | unsigned long size, ofs; |
Matt Redfearn | 3798fd1 | 2017-03-21 14:52:25 +0000 | [diff] [blame] | 493 | struct pt_regs *regs; |
Franck Bui-Huu | 4d157d5 | 2006-08-03 09:29:21 +0200 | [diff] [blame] | 494 | int leaf; |
Atsushi Nemoto | f66686f | 2006-07-29 23:27:20 +0900 | [diff] [blame] | 495 | |
Atsushi Nemoto | f66686f | 2006-07-29 23:27:20 +0900 | [diff] [blame] | 496 | if (!stack_page) |
| 497 | return 0; |
| 498 | |
Atsushi Nemoto | 1924600 | 2006-09-29 18:02:51 +0900 | [diff] [blame] | 499 | /* |
Matt Redfearn | 3798fd1 | 2017-03-21 14:52:25 +0000 | [diff] [blame] | 500 | * IRQ stacks start at IRQ_STACK_START |
| 501 | * task stacks at THREAD_SIZE - 32 |
Atsushi Nemoto | 1924600 | 2006-09-29 18:02:51 +0900 | [diff] [blame] | 502 | */ |
Matt Redfearn | 3798fd1 | 2017-03-21 14:52:25 +0000 | [diff] [blame] | 503 | low = stack_page; |
| 504 | if (!preemptible() && on_irq_stack(raw_smp_processor_id(), *sp)) { |
| 505 | high = stack_page + IRQ_STACK_START; |
| 506 | irq_stack_high = high; |
| 507 | } else { |
| 508 | high = stack_page + THREAD_SIZE - 32; |
| 509 | irq_stack_high = 0; |
| 510 | } |
| 511 | |
| 512 | /* |
| 513 | * If we reached the top of the interrupt stack, start unwinding |
| 514 | * the interrupted task stack. |
| 515 | */ |
| 516 | if (unlikely(*sp == irq_stack_high)) { |
| 517 | unsigned long task_sp = *(unsigned long *)*sp; |
| 518 | |
| 519 | /* |
| 520 | * Check that the pointer saved in the IRQ stack head points to |
| 521 | * something within the stack of the current task |
| 522 | */ |
| 523 | if (!object_is_on_stack((void *)task_sp)) |
| 524 | return 0; |
| 525 | |
| 526 | /* |
| 527 | * Follow pointer to tasks kernel stack frame where interrupted |
| 528 | * state was saved. |
| 529 | */ |
| 530 | regs = (struct pt_regs *)task_sp; |
| 531 | pc = regs->cp0_epc; |
| 532 | if (!user_mode(regs) && __kernel_text_address(pc)) { |
| 533 | *sp = regs->regs[29]; |
| 534 | *ra = regs->regs[31]; |
| 535 | return pc; |
Atsushi Nemoto | 1924600 | 2006-09-29 18:02:51 +0900 | [diff] [blame] | 536 | } |
| 537 | return 0; |
| 538 | } |
Franck Bui-Huu | 55b7428 | 2006-10-13 13:37:35 +0200 | [diff] [blame] | 539 | if (!kallsyms_lookup_size_offset(pc, &size, &ofs)) |
Atsushi Nemoto | f66686f | 2006-07-29 23:27:20 +0900 | [diff] [blame] | 540 | return 0; |
Franck Bui-Huu | 1fd6909 | 2006-08-18 16:18:07 +0200 | [diff] [blame] | 541 | /* |
Lucas De Marchi | 25985ed | 2011-03-30 22:57:33 -0300 | [diff] [blame] | 542 | * Return ra if an exception occurred at the first instruction |
Franck Bui-Huu | 1fd6909 | 2006-08-18 16:18:07 +0200 | [diff] [blame] | 543 | */ |
Atsushi Nemoto | 1924600 | 2006-09-29 18:02:51 +0900 | [diff] [blame] | 544 | if (unlikely(ofs == 0)) { |
| 545 | pc = *ra; |
| 546 | *ra = 0; |
| 547 | return pc; |
| 548 | } |
Atsushi Nemoto | f66686f | 2006-07-29 23:27:20 +0900 | [diff] [blame] | 549 | |
| 550 | info.func = (void *)(pc - ofs); |
| 551 | info.func_size = ofs; /* analyze from start to ofs */ |
Franck Bui-Huu | 4d157d5 | 2006-08-03 09:29:21 +0200 | [diff] [blame] | 552 | leaf = get_frame_info(&info); |
| 553 | if (leaf < 0) |
Atsushi Nemoto | f66686f | 2006-07-29 23:27:20 +0900 | [diff] [blame] | 554 | return 0; |
| 555 | |
Matt Redfearn | 3798fd1 | 2017-03-21 14:52:25 +0000 | [diff] [blame] | 556 | if (*sp < low || *sp + info.frame_size > high) |
Franck Bui-Huu | 4d157d5 | 2006-08-03 09:29:21 +0200 | [diff] [blame] | 557 | return 0; |
| 558 | |
| 559 | if (leaf) |
| 560 | /* |
| 561 | * For some extreme cases, get_frame_info() can |
| 562 | * consider wrongly a nested function as a leaf |
| 563 | * one. In that cases avoid to return always the |
| 564 | * same value. |
| 565 | */ |
Atsushi Nemoto | 1924600 | 2006-09-29 18:02:51 +0900 | [diff] [blame] | 566 | pc = pc != *ra ? *ra : 0; |
Franck Bui-Huu | 4d157d5 | 2006-08-03 09:29:21 +0200 | [diff] [blame] | 567 | else |
| 568 | pc = ((unsigned long *)(*sp))[info.pc_offset]; |
| 569 | |
| 570 | *sp += info.frame_size; |
Atsushi Nemoto | 1924600 | 2006-09-29 18:02:51 +0900 | [diff] [blame] | 571 | *ra = 0; |
Franck Bui-Huu | 4d157d5 | 2006-08-03 09:29:21 +0200 | [diff] [blame] | 572 | return __kernel_text_address(pc) ? pc : 0; |
Atsushi Nemoto | f66686f | 2006-07-29 23:27:20 +0900 | [diff] [blame] | 573 | } |
Daniel Kalmar | 94ea09c | 2011-05-13 08:38:04 -0400 | [diff] [blame] | 574 | EXPORT_SYMBOL(unwind_stack_by_address); |
| 575 | |
| 576 | /* used by show_backtrace() */ |
| 577 | unsigned long unwind_stack(struct task_struct *task, unsigned long *sp, |
| 578 | unsigned long pc, unsigned long *ra) |
| 579 | { |
Matt Redfearn | 86b54e4 | 2016-12-19 14:20:57 +0000 | [diff] [blame] | 580 | unsigned long stack_page = 0; |
| 581 | int cpu; |
| 582 | |
| 583 | for_each_possible_cpu(cpu) { |
| 584 | if (on_irq_stack(cpu, *sp)) { |
| 585 | stack_page = (unsigned long)irq_stack[cpu]; |
| 586 | break; |
| 587 | } |
| 588 | } |
| 589 | |
| 590 | if (!stack_page) |
| 591 | stack_page = (unsigned long)task_stack_page(task); |
| 592 | |
Daniel Kalmar | 94ea09c | 2011-05-13 08:38:04 -0400 | [diff] [blame] | 593 | return unwind_stack_by_address(stack_page, sp, pc, ra); |
| 594 | } |
Atsushi Nemoto | f66686f | 2006-07-29 23:27:20 +0900 | [diff] [blame] | 595 | #endif |
Franck Bui-Huu | b594318 | 2006-08-18 16:18:09 +0200 | [diff] [blame] | 596 | |
| 597 | /* |
| 598 | * get_wchan - a maintenance nightmare^W^Wpain in the ass ... |
| 599 | */ |
| 600 | unsigned long get_wchan(struct task_struct *task) |
| 601 | { |
| 602 | unsigned long pc = 0; |
| 603 | #ifdef CONFIG_KALLSYMS |
| 604 | unsigned long sp; |
Atsushi Nemoto | 1924600 | 2006-09-29 18:02:51 +0900 | [diff] [blame] | 605 | unsigned long ra = 0; |
Franck Bui-Huu | b594318 | 2006-08-18 16:18:09 +0200 | [diff] [blame] | 606 | #endif |
| 607 | |
| 608 | if (!task || task == current || task->state == TASK_RUNNING) |
| 609 | goto out; |
| 610 | if (!task_stack_page(task)) |
| 611 | goto out; |
| 612 | |
| 613 | pc = thread_saved_pc(task); |
| 614 | |
| 615 | #ifdef CONFIG_KALLSYMS |
| 616 | sp = task->thread.reg29 + schedule_mfi.frame_size; |
| 617 | |
| 618 | while (in_sched_functions(pc)) |
Atsushi Nemoto | 1924600 | 2006-09-29 18:02:51 +0900 | [diff] [blame] | 619 | pc = unwind_stack(task, &sp, pc, &ra); |
Franck Bui-Huu | b594318 | 2006-08-18 16:18:09 +0200 | [diff] [blame] | 620 | #endif |
| 621 | |
| 622 | out: |
| 623 | return pc; |
| 624 | } |
Franck Bui-Huu | 9410910 | 2007-07-19 14:04:21 +0200 | [diff] [blame] | 625 | |
| 626 | /* |
| 627 | * Don't forget that the stack pointer must be aligned on a 8 bytes |
| 628 | * boundary for 32-bits ABI and 16 bytes for 64-bits ABI. |
| 629 | */ |
| 630 | unsigned long arch_align_stack(unsigned long sp) |
| 631 | { |
| 632 | if (!(current->personality & ADDR_NO_RANDOMIZE) && randomize_va_space) |
| 633 | sp -= get_random_int() & ~PAGE_MASK; |
| 634 | |
| 635 | return sp & ALMASK; |
| 636 | } |
Eunbong Song | 856839b | 2014-10-22 06:39:56 +0000 | [diff] [blame] | 637 | |
Paul Burton | dc9e795 | 2018-06-22 10:55:46 -0700 | [diff] [blame] | 638 | static DEFINE_PER_CPU(struct call_single_data, backtrace_csd); |
| 639 | static struct cpumask backtrace_csd_busy; |
| 640 | |
| 641 | static void handle_backtrace(void *info) |
Eunbong Song | 856839b | 2014-10-22 06:39:56 +0000 | [diff] [blame] | 642 | { |
Paul Burton | dc9e795 | 2018-06-22 10:55:46 -0700 | [diff] [blame] | 643 | nmi_cpu_backtrace(get_irq_regs()); |
| 644 | cpumask_clear_cpu(smp_processor_id(), &backtrace_csd_busy); |
| 645 | } |
Eunbong Song | 856839b | 2014-10-22 06:39:56 +0000 | [diff] [blame] | 646 | |
Paul Burton | dc9e795 | 2018-06-22 10:55:46 -0700 | [diff] [blame] | 647 | static void raise_backtrace(cpumask_t *mask) |
| 648 | { |
| 649 | struct call_single_data *csd; |
| 650 | int cpu; |
Eunbong Song | 856839b | 2014-10-22 06:39:56 +0000 | [diff] [blame] | 651 | |
Paul Burton | dc9e795 | 2018-06-22 10:55:46 -0700 | [diff] [blame] | 652 | for_each_cpu(cpu, mask) { |
| 653 | /* |
| 654 | * If we previously sent an IPI to the target CPU & it hasn't |
| 655 | * cleared its bit in the busy cpumask then it didn't handle |
| 656 | * our previous IPI & it's not safe for us to reuse the |
| 657 | * call_single_data_t. |
| 658 | */ |
| 659 | if (cpumask_test_and_set_cpu(cpu, &backtrace_csd_busy)) { |
| 660 | pr_warn("Unable to send backtrace IPI to CPU%u - perhaps it hung?\n", |
| 661 | cpu); |
| 662 | continue; |
| 663 | } |
| 664 | |
| 665 | csd = &per_cpu(backtrace_csd, cpu); |
| 666 | csd->func = handle_backtrace; |
| 667 | smp_call_function_single_async(cpu, csd); |
| 668 | } |
Eunbong Song | 856839b | 2014-10-22 06:39:56 +0000 | [diff] [blame] | 669 | } |
| 670 | |
Chris Metcalf | 9a01c3e | 2016-10-07 17:02:45 -0700 | [diff] [blame] | 671 | void arch_trigger_cpumask_backtrace(const cpumask_t *mask, bool exclude_self) |
Eunbong Song | 856839b | 2014-10-22 06:39:56 +0000 | [diff] [blame] | 672 | { |
Paul Burton | dc9e795 | 2018-06-22 10:55:46 -0700 | [diff] [blame] | 673 | nmi_trigger_cpumask_backtrace(mask, exclude_self, raise_backtrace); |
Eunbong Song | 856839b | 2014-10-22 06:39:56 +0000 | [diff] [blame] | 674 | } |
Paul Burton | 9791554 | 2015-01-08 12:17:37 +0000 | [diff] [blame] | 675 | |
| 676 | int mips_get_process_fp_mode(struct task_struct *task) |
| 677 | { |
| 678 | int value = 0; |
| 679 | |
| 680 | if (!test_tsk_thread_flag(task, TIF_32BIT_FPREGS)) |
| 681 | value |= PR_FP_MODE_FR; |
| 682 | if (test_tsk_thread_flag(task, TIF_HYBRID_FPREGS)) |
| 683 | value |= PR_FP_MODE_FRE; |
| 684 | |
| 685 | return value; |
| 686 | } |
| 687 | |
Paul Burton | 6b83225 | 2016-04-21 12:43:58 +0100 | [diff] [blame] | 688 | static void prepare_for_fp_mode_switch(void *info) |
| 689 | { |
| 690 | struct mm_struct *mm = info; |
| 691 | |
| 692 | if (current->mm == mm) |
| 693 | lose_fpu(1); |
| 694 | } |
| 695 | |
Paul Burton | 9791554 | 2015-01-08 12:17:37 +0000 | [diff] [blame] | 696 | int mips_set_process_fp_mode(struct task_struct *task, unsigned int value) |
| 697 | { |
| 698 | const unsigned int known_bits = PR_FP_MODE_FR | PR_FP_MODE_FRE; |
Paul Burton | 9791554 | 2015-01-08 12:17:37 +0000 | [diff] [blame] | 699 | struct task_struct *t; |
Paul Burton | 6b83225 | 2016-04-21 12:43:58 +0100 | [diff] [blame] | 700 | int max_users; |
Paul Burton | 9791554 | 2015-01-08 12:17:37 +0000 | [diff] [blame] | 701 | |
Maciej W. Rozycki | 14e1c57 | 2017-11-27 09:33:03 +0000 | [diff] [blame] | 702 | /* If nothing to change, return right away, successfully. */ |
| 703 | if (value == mips_get_process_fp_mode(task)) |
| 704 | return 0; |
| 705 | |
| 706 | /* Only accept a mode change if 64-bit FP enabled for o32. */ |
| 707 | if (!IS_ENABLED(CONFIG_MIPS_O32_FP64_SUPPORT)) |
| 708 | return -EOPNOTSUPP; |
| 709 | |
| 710 | /* And only for o32 tasks. */ |
| 711 | if (IS_ENABLED(CONFIG_64BIT) && !test_thread_flag(TIF_32BIT_REGS)) |
| 712 | return -EOPNOTSUPP; |
| 713 | |
Paul Burton | 9791554 | 2015-01-08 12:17:37 +0000 | [diff] [blame] | 714 | /* Check the value is valid */ |
| 715 | if (value & ~known_bits) |
| 716 | return -EOPNOTSUPP; |
| 717 | |
Maciej W. Rozycki | ef1b8fb | 2018-05-15 23:04:44 +0100 | [diff] [blame] | 718 | /* Setting FRE without FR is not supported. */ |
| 719 | if ((value & (PR_FP_MODE_FR | PR_FP_MODE_FRE)) == PR_FP_MODE_FRE) |
| 720 | return -EOPNOTSUPP; |
| 721 | |
Paul Burton | 9791554 | 2015-01-08 12:17:37 +0000 | [diff] [blame] | 722 | /* Avoid inadvertently triggering emulation */ |
Marcin Nowakowski | b244614 | 2016-08-31 12:33:23 +0200 | [diff] [blame] | 723 | if ((value & PR_FP_MODE_FR) && raw_cpu_has_fpu && |
| 724 | !(raw_current_cpu_data.fpu_id & MIPS_FPIR_F64)) |
Paul Burton | 9791554 | 2015-01-08 12:17:37 +0000 | [diff] [blame] | 725 | return -EOPNOTSUPP; |
Marcin Nowakowski | b244614 | 2016-08-31 12:33:23 +0200 | [diff] [blame] | 726 | if ((value & PR_FP_MODE_FRE) && raw_cpu_has_fpu && !cpu_has_fre) |
Paul Burton | 9791554 | 2015-01-08 12:17:37 +0000 | [diff] [blame] | 727 | return -EOPNOTSUPP; |
| 728 | |
Markos Chandras | 13e45f0 | 2015-01-13 13:01:49 +0000 | [diff] [blame] | 729 | /* FR = 0 not supported in MIPS R6 */ |
Marcin Nowakowski | b244614 | 2016-08-31 12:33:23 +0200 | [diff] [blame] | 730 | if (!(value & PR_FP_MODE_FR) && raw_cpu_has_fpu && cpu_has_mips_r6) |
Markos Chandras | 13e45f0 | 2015-01-13 13:01:49 +0000 | [diff] [blame] | 731 | return -EOPNOTSUPP; |
| 732 | |
Paul Burton | bd239f1 | 2016-04-21 12:43:57 +0100 | [diff] [blame] | 733 | /* Proceed with the mode switch */ |
| 734 | preempt_disable(); |
| 735 | |
Paul Burton | 9791554 | 2015-01-08 12:17:37 +0000 | [diff] [blame] | 736 | /* Save FP & vector context, then disable FPU & MSA */ |
| 737 | if (task->signal == current->signal) |
| 738 | lose_fpu(1); |
| 739 | |
| 740 | /* Prevent any threads from obtaining live FP context */ |
| 741 | atomic_set(&task->mm->context.fp_mode_switching, 1); |
| 742 | smp_mb__after_atomic(); |
| 743 | |
| 744 | /* |
Paul Burton | 6b83225 | 2016-04-21 12:43:58 +0100 | [diff] [blame] | 745 | * If there are multiple online CPUs then force any which are running |
| 746 | * threads in this process to lose their FPU context, which they can't |
| 747 | * regain until fp_mode_switching is cleared later. |
Paul Burton | 9791554 | 2015-01-08 12:17:37 +0000 | [diff] [blame] | 748 | */ |
| 749 | if (num_online_cpus() > 1) { |
Paul Burton | 6b83225 | 2016-04-21 12:43:58 +0100 | [diff] [blame] | 750 | /* No need to send an IPI for the local CPU */ |
| 751 | max_users = (task->mm == current->mm) ? 1 : 0; |
Paul Burton | 9791554 | 2015-01-08 12:17:37 +0000 | [diff] [blame] | 752 | |
Paul Burton | 6b83225 | 2016-04-21 12:43:58 +0100 | [diff] [blame] | 753 | if (atomic_read(¤t->mm->mm_users) > max_users) |
| 754 | smp_call_function(prepare_for_fp_mode_switch, |
| 755 | (void *)current->mm, 1); |
Paul Burton | 9791554 | 2015-01-08 12:17:37 +0000 | [diff] [blame] | 756 | } |
| 757 | |
| 758 | /* |
| 759 | * There are now no threads of the process with live FP context, so it |
| 760 | * is safe to proceed with the FP mode switch. |
| 761 | */ |
| 762 | for_each_thread(task, t) { |
| 763 | /* Update desired FP register width */ |
| 764 | if (value & PR_FP_MODE_FR) { |
| 765 | clear_tsk_thread_flag(t, TIF_32BIT_FPREGS); |
| 766 | } else { |
| 767 | set_tsk_thread_flag(t, TIF_32BIT_FPREGS); |
| 768 | clear_tsk_thread_flag(t, TIF_MSA_CTX_LIVE); |
| 769 | } |
| 770 | |
| 771 | /* Update desired FP single layout */ |
| 772 | if (value & PR_FP_MODE_FRE) |
| 773 | set_tsk_thread_flag(t, TIF_HYBRID_FPREGS); |
| 774 | else |
| 775 | clear_tsk_thread_flag(t, TIF_HYBRID_FPREGS); |
| 776 | } |
| 777 | |
| 778 | /* Allow threads to use FP again */ |
| 779 | atomic_set(&task->mm->context.fp_mode_switching, 0); |
Paul Burton | bd239f1 | 2016-04-21 12:43:57 +0100 | [diff] [blame] | 780 | preempt_enable(); |
Paul Burton | 9791554 | 2015-01-08 12:17:37 +0000 | [diff] [blame] | 781 | |
| 782 | return 0; |
| 783 | } |