/* * Derived from "arch/i386/kernel/process.c" * Copyright (C) 1995 Linus Torvalds * * Updated and modified by Cort Dougan (cort@cs.nmt.edu) and * Paul Mackerras (paulus@cs.anu.edu.au) * * PowerPC version * Copyright (C) 1995-1996 Gary Thomas (gdt@linuxppc.org) * * This program is free software; you can redistribute it and/or * modify it under the terms of the GNU General Public License * as published by the Free Software Foundation; either version * 2 of the License, or (at your option) any later version. */ #include <linux/errno.h> #include <linux/sched.h> #include <linux/kernel.h> #include <linux/mm.h> #include <linux/smp.h> #include <linux/stddef.h> #include <linux/unistd.h> #include <linux/ptrace.h> #include <linux/slab.h> #include <linux/user.h> #include <linux/elf.h> #include <linux/init.h> #include <linux/prctl.h> #include <linux/init_task.h> #include <linux/module.h> #include <linux/kallsyms.h> #include <linux/mqueue.h> #include <linux/hardirq.h> #include <linux/utsname.h> #include <asm/pgtable.h> #include <asm/uaccess.h> #include <asm/system.h> #include <asm/io.h> #include <asm/processor.h> #include <asm/mmu.h> #include <asm/prom.h> #include <asm/machdep.h> #include <asm/time.h> #include <asm/syscalls.h> #ifdef CONFIG_PPC64 #include <asm/firmware.h> #endif extern unsigned long _get_SP(void); #ifndef CONFIG_SMP struct task_struct *last_task_used_math = NULL; struct task_struct *last_task_used_altivec = NULL; struct task_struct *last_task_used_spe = NULL; #endif /* * Make sure the floating-point register state in the * the thread_struct is up to date for task tsk. */ void flush_fp_to_thread(struct task_struct *tsk) { if (tsk->thread.regs) { /* * We need to disable preemption here because if we didn't, * another process could get scheduled after the regs->msr * test but before we have finished saving the FP registers * to the thread_struct. That process could take over the * FPU, and then when we get scheduled again we would store * bogus values for the remaining FP registers. */ preempt_disable(); if (tsk->thread.regs->msr & MSR_FP) { #ifdef CONFIG_SMP /* * This should only ever be called for current or * for a stopped child process. Since we save away * the FP register state on context switch on SMP, * there is something wrong if a stopped child appears * to still have its FP state in the CPU registers. */ BUG_ON(tsk != current); #endif giveup_fpu(tsk); } preempt_enable(); } } void enable_kernel_fp(void) { WARN_ON(preemptible()); #ifdef CONFIG_SMP if (current->thread.regs && (current->thread.regs->msr & MSR_FP)) giveup_fpu(current); else giveup_fpu(NULL); /* just enables FP for kernel */ #else giveup_fpu(last_task_used_math); #endif /* CONFIG_SMP */ } EXPORT_SYMBOL(enable_kernel_fp); int dump_task_fpu(struct task_struct *tsk, elf_fpregset_t *fpregs) { if (!tsk->thread.regs) return 0; flush_fp_to_thread(current); memcpy(fpregs, &tsk->thread.fpr[0], sizeof(*fpregs)); return 1; } #ifdef CONFIG_ALTIVEC void enable_kernel_altivec(void) { WARN_ON(preemptible()); #ifdef CONFIG_SMP if (current->thread.regs && (current->thread.regs->msr & MSR_VEC)) giveup_altivec(current); else giveup_altivec(NULL); /* just enable AltiVec for kernel - force */ #else giveup_altivec(last_task_used_altivec); #endif /* CONFIG_SMP */ } EXPORT_SYMBOL(enable_kernel_altivec); /* * Make sure the VMX/Altivec register state in the * the thread_struct is up to date for task tsk. */ void flush_altivec_to_thread(struct task_struct *tsk) { if (tsk->thread.regs) { preempt_disable(); if (tsk->thread.regs->msr & MSR_VEC) { #ifdef CONFIG_SMP BUG_ON(tsk != current); #endif giveup_altivec(tsk); } preempt_enable(); } } int dump_task_altivec(struct task_struct *tsk, elf_vrregset_t *vrregs) { /* ELF_NVRREG includes the VSCR and VRSAVE which we need to save * separately, see below */ const int nregs = ELF_NVRREG - 2; elf_vrreg_t *reg; u32 *dest; if (tsk == current) flush_altivec_to_thread(tsk); reg = (elf_vrreg_t *)vrregs; /* copy the 32 vr registers */ memcpy(reg, &tsk->thread.vr[0], nregs * sizeof(*reg)); reg += nregs; /* copy the vscr */ memcpy(reg, &tsk->thread.vscr, sizeof(*reg)); reg++; /* vrsave is stored in the high 32bit slot of the final 128bits */ memset(reg, 0, sizeof(*reg)); dest = (u32 *)reg; *dest = tsk->thread.vrsave; return 1; } #endif /* CONFIG_ALTIVEC */ #ifdef CONFIG_SPE void enable_kernel_spe(void) { WARN_ON(preemptible()); #ifdef CONFIG_SMP if (current->thread.regs && (current->thread.regs->msr & MSR_SPE)) giveup_spe(current); else giveup_spe(NULL); /* just enable SPE for kernel - force */ #else giveup_spe(last_task_used_spe); #endif /* __SMP __ */ } EXPORT_SYMBOL(enable_kernel_spe); void flush_spe_to_thread(struct task_struct *tsk) { if (tsk->thread.regs) { preempt_disable(); if (tsk->thread.regs->msr & MSR_SPE) { #ifdef CONFIG_SMP BUG_ON(tsk != current); #endif giveup_spe(tsk); } preempt_enable(); } } int dump_spe(struct pt_regs *regs, elf_vrregset_t *evrregs) { flush_spe_to_thread(current); /* We copy u32 evr[32] + u64 acc + u32 spefscr -> 35 */ memcpy(evrregs, ¤t->thread.evr[0], sizeof(u32) * 35); return 1; } #endif /* CONFIG_SPE */ #ifndef CONFIG_SMP /* * If we are doing lazy switching of CPU state (FP, altivec or SPE), * and the current task has some state, discard it. */ void discard_lazy_cpu_state(void) { preempt_disable(); if (last_task_used_math == current) last_task_used_math = NULL; #ifdef CONFIG_ALTIVEC if (last_task_used_altivec == current) last_task_used_altivec = NULL; #endif /* CONFIG_ALTIVEC */ #ifdef CONFIG_SPE if (last_task_used_spe == current) last_task_used_spe = NULL; #endif preempt_enable(); } #endif /* CONFIG_SMP */ static DEFINE_PER_CPU(unsigned long, current_dabr); int set_dabr(unsigned long dabr) { __get_cpu_var(current_dabr) = dabr; #ifdef CONFIG_PPC_MERGE /* XXX for now */ if (ppc_md.set_dabr) return ppc_md.set_dabr(dabr); #endif /* XXX should we have a CPU_FTR_HAS_DABR ? */ #if defined(CONFIG_PPC64) || defined(CONFIG_6xx) mtspr(SPRN_DABR, dabr); #endif return 0; } #ifdef CONFIG_PPC64 DEFINE_PER_CPU(struct cpu_usage, cpu_usage_array); #endif struct task_struct *__switch_to(struct task_struct *prev, struct task_struct *new) { struct thread_struct *new_thread, *old_thread; unsigned long flags; struct task_struct *last; #ifdef CONFIG_SMP /* avoid complexity of lazy save/restore of fpu * by just saving it every time we switch out if * this task used the fpu during the last quantum. * * If it tries to use the fpu again, it'll trap and * reload its fp regs. So we don't have to do a restore * every switch, just a save. * -- Cort */ if (prev->thread.regs && (prev->thread.regs->msr & MSR_FP)) giveup_fpu(prev); #ifdef CONFIG_ALTIVEC /* * If the previous thread used altivec in the last quantum * (thus changing altivec regs) then save them. * We used to check the VRSAVE register but not all apps * set it, so we don't rely on it now (and in fact we need * to save & restore VSCR even if VRSAVE == 0). -- paulus * * On SMP we always save/restore altivec regs just to avoid the * complexity of changing processors. * -- Cort */ if (prev->thread.regs && (prev->thread.regs->msr & MSR_VEC)) giveup_altivec(prev); #endif /* CONFIG_ALTIVEC */ #ifdef CONFIG_SPE /* * If the previous thread used spe in the last quantum * (thus changing spe regs) then save them. * * On SMP we always save/restore spe regs just to avoid the * complexity of changing processors. */ if ((prev->thread.regs && (prev->thread.regs->msr & MSR_SPE))) giveup_spe(prev); #endif /* CONFIG_SPE */ #else /* CONFIG_SMP */ #ifdef CONFIG_ALTIVEC /* Avoid the trap. On smp this this never happens since * we don't set last_task_used_altivec -- Cort */ if (new->thread.regs && last_task_used_altivec == new) new->thread.regs->msr |= MSR_VEC; #endif /* CONFIG_ALTIVEC */ #ifdef CONFIG_SPE /* Avoid the trap. On smp this this never happens since * we don't set last_task_used_spe */ if (new->thread.regs && last_task_used_spe == new) new->thread.regs->msr |= MSR_SPE; #endif /* CONFIG_SPE */ #endif /* CONFIG_SMP */ if (unlikely(__get_cpu_var(current_dabr) != new->thread.dabr)) set_dabr(new->thread.dabr); new_thread = &new->thread; old_thread = ¤t->thread; #ifdef CONFIG_PPC64 /* * Collect processor utilization data per process */ if (firmware_has_feature(FW_FEATURE_SPLPAR)) { struct cpu_usage *cu = &__get_cpu_var(cpu_usage_array); long unsigned start_tb, current_tb; start_tb = old_thread->start_tb; cu->current_tb = current_tb = mfspr(SPRN_PURR); old_thread->accum_tb += (current_tb - start_tb); new_thread->start_tb = current_tb; } #endif local_irq_save(flags); account_system_vtime(current); account_process_vtime(current); calculate_steal_time(); /* * We can't take a PMU exception inside _switch() since there is a * window where the kernel stack SLB and the kernel stack are out * of sync. Hard disable here. */ hard_irq_disable(); last = _switch(old_thread, new_thread); local_irq_restore(flags); return last; } static int instructions_to_print = 16; static void show_instructions(struct pt_regs *regs) { int i; unsigned long pc = regs->nip - (instructions_to_print * 3 / 4 * sizeof(int)); printk("Instruction dump:"); for (i = 0; i < instructions_to_print; i++) { int instr; if (!(i % 8)) printk("\n"); #if !defined(CONFIG_BOOKE) /* If executing with the IMMU off, adjust pc rather * than print XXXXXXXX. */ if (!(regs->msr & MSR_IR)) pc = (unsigned long)phys_to_virt(pc); #endif /* We use __get_user here *only* to avoid an OOPS on a * bad address because the pc *should* only be a * kernel address. */ if (!__kernel_text_address(pc) || __get_user(instr, (unsigned int __user *)pc)) { printk("XXXXXXXX "); } else { if (regs->nip == pc) printk("<%08x> ", instr); else printk("%08x ", instr); } pc += sizeof(int); } printk("\n"); } static struct regbit { unsigned long bit; const char *name; } msr_bits[] = { {MSR_EE, "EE"}, {MSR_PR, "PR"}, {MSR_FP, "FP"}, {MSR_ME, "ME"}, {MSR_IR, "IR"}, {MSR_DR, "DR"}, {0, NULL} }; static void printbits(unsigned long val, struct regbit *bits) { const char *sep = ""; printk("<"); for (; bits->bit; ++bits) if (val & bits->bit) { printk("%s%s", sep, bits->name); sep = ","; } printk(">"); } #ifdef CONFIG_PPC64 #define REG "%016lx" #define REGS_PER_LINE 4 #define LAST_VOLATILE 13 #else #define REG "%08lx" #define REGS_PER_LINE 8 #define LAST_VOLATILE 12 #endif void show_regs(struct pt_regs * regs) { int i, trap; printk("NIP: "REG" LR: "REG" CTR: "REG"\n", regs->nip, regs->link, regs->ctr); printk("REGS: %p TRAP: %04lx %s (%s)\n", regs, regs->trap, print_tainted(), init_utsname()->release); printk("MSR: "REG" ", regs->msr); printbits(regs->msr, msr_bits); printk(" CR: %08lx XER: %08lx\n", regs->ccr, regs->xer); trap = TRAP(regs); if (trap == 0x300 || trap == 0x600) #if defined(CONFIG_4xx) || defined(CONFIG_BOOKE) printk("DEAR: "REG", ESR: "REG"\n", regs->dar, regs->dsisr); #else printk("DAR: "REG", DSISR: "REG"\n", regs->dar, regs->dsisr); #endif printk("TASK = %p[%d] '%s' THREAD: %p", current, task_pid_nr(current), current->comm, task_thread_info(current)); #ifdef CONFIG_SMP printk(" CPU: %d", raw_smp_processor_id()); #endif /* CONFIG_SMP */ for (i = 0; i < 32; i++) { if ((i % REGS_PER_LINE) == 0) printk("\n" KERN_INFO "GPR%02d: ", i); printk(REG " ", regs->gpr[i]); if (i == LAST_VOLATILE && !FULL_REGS(regs)) break; } printk("\n"); #ifdef CONFIG_KALLSYMS /* * Lookup NIP late so we have the best change of getting the * above info out without failing */ printk("NIP ["REG"] ", regs->nip); print_symbol("%s\n", regs->nip); printk("LR ["REG"] ", regs->link); print_symbol("%s\n", regs->link); #endif show_stack(current, (unsigned long *) regs->gpr[1]); if (!user_mode(regs)) show_instructions(regs); } void exit_thread(void) { discard_lazy_cpu_state(); } void flush_thread(void) { #ifdef CONFIG_PPC64 struct thread_info *t = current_thread_info(); if (test_ti_thread_flag(t, TIF_ABI_PENDING)) { clear_ti_thread_flag(t, TIF_ABI_PENDING); if (test_ti_thread_flag(t, TIF_32BIT)) clear_ti_thread_flag(t, TIF_32BIT); else set_ti_thread_flag(t, TIF_32BIT); } #endif discard_lazy_cpu_state(); if (current->thread.dabr) { current->thread.dabr = 0; set_dabr(0); } } void release_thread(struct task_struct *t) { } /* * This gets called before we allocate a new thread and copy * the current task into it. */ void prepare_to_copy(struct task_struct *tsk) { flush_fp_to_thread(current); flush_altivec_to_thread(current); flush_spe_to_thread(current); } /* * Copy a thread.. */ int copy_thread(int nr, unsigned long clone_flags, unsigned long usp, unsigned long unused, struct task_struct *p, struct pt_regs *regs) { struct pt_regs *childregs, *kregs; extern void ret_from_fork(void); unsigned long sp = (unsigned long)task_stack_page(p) + THREAD_SIZE; CHECK_FULL_REGS(regs); /* Copy registers */ sp -= sizeof(struct pt_regs); childregs = (struct pt_regs *) sp; *childregs = *regs; if ((childregs->msr & MSR_PR) == 0) { /* for kernel thread, set `current' and stackptr in new task */ childregs->gpr[1] = sp + sizeof(struct pt_regs); #ifdef CONFIG_PPC32 childregs->gpr[2] = (unsigned long) p; #else clear_tsk_thread_flag(p, TIF_32BIT); #endif p->thread.regs = NULL; /* no user register state */ } else { childregs->gpr[1] = usp; p->thread.regs = childregs; if (clone_flags & CLONE_SETTLS) { #ifdef CONFIG_PPC64 if (!test_thread_flag(TIF_32BIT)) childregs->gpr[13] = childregs->gpr[6]; else #endif childregs->gpr[2] = childregs->gpr[6]; } } childregs->gpr[3] = 0; /* Result from fork() */ sp -= STACK_FRAME_OVERHEAD; /* * The way this works is that at some point in the future * some task will call _switch to switch to the new task. * That will pop off the stack frame created below and start * the new task running at ret_from_fork. The new task will * do some house keeping and then return from the fork or clone * system call, using the stack frame created above. */ sp -= sizeof(struct pt_regs); kregs = (struct pt_regs *) sp; sp -= STACK_FRAME_OVERHEAD; p->thread.ksp = sp; #ifdef CONFIG_PPC64 if (cpu_has_feature(CPU_FTR_SLB)) { unsigned long sp_vsid; unsigned long llp = mmu_psize_defs[mmu_linear_psize].sllp; if (cpu_has_feature(CPU_FTR_1T_SEGMENT)) sp_vsid = get_kernel_vsid(sp, MMU_SEGSIZE_1T) << SLB_VSID_SHIFT_1T; else sp_vsid = get_kernel_vsid(sp, MMU_SEGSIZE_256M) << SLB_VSID_SHIFT; sp_vsid |= SLB_VSID_KERNEL | llp; p->thread.ksp_vsid = sp_vsid; } /* * The PPC64 ABI makes use of a TOC to contain function * pointers. The function (ret_from_except) is actually a pointer * to the TOC entry. The first entry is a pointer to the actual * function. */ kregs->nip = *((unsigned long *)ret_from_fork); #else kregs->nip = (unsigned long)ret_from_fork; #endif return 0; } /* * Set up a thread for executing a new program */ void start_thread(struct pt_regs *regs, unsigned long start, unsigned long sp) { #ifdef CONFIG_PPC64 unsigned long load_addr = regs->gpr[2]; /* saved by ELF_PLAT_INIT */ #endif set_fs(USER_DS); /* * If we exec out of a kernel thread then thread.regs will not be * set. Do it now. */ if (!current->thread.regs) { struct pt_regs *regs = task_stack_page(current) + THREAD_SIZE; current->thread.regs = regs - 1; } memset(regs->gpr, 0, sizeof(regs->gpr)); regs->ctr = 0; regs->link = 0; regs->xer = 0; regs->ccr = 0; regs->gpr[1] = sp; /* * We have just cleared all the nonvolatile GPRs, so make * FULL_REGS(regs) return true. This is necessary to allow * ptrace to examine the thread immediately after exec. */ regs->trap &= ~1UL; #ifdef CONFIG_PPC32 regs->mq = 0; regs->nip = start; regs->msr = MSR_USER; #else if (!test_thread_flag(TIF_32BIT)) { unsigned long entry, toc; /* start is a relocated pointer to the function descriptor for * the elf _start routine. The first entry in the function * descriptor is the entry address of _start and the second * entry is the TOC value we need to use. */ __get_user(entry, (unsigned long __user *)start); __get_user(toc, (unsigned long __user *)start+1); /* Check whether the e_entry function descriptor entries * need to be relocated before we can use them. */ if (load_addr != 0) { entry += load_addr; toc += load_addr; } regs->nip = entry; regs->gpr[2] = toc; regs->msr = MSR_USER64; } else { regs->nip = start; regs->gpr[2] = 0; regs->msr = MSR_USER32; } #endif discard_lazy_cpu_state(); memset(current->thread.fpr, 0, sizeof(current->thread.fpr)); current->thread.fpscr.val = 0; #ifdef CONFIG_ALTIVEC memset(current->thread.vr, 0, sizeof(current->thread.vr)); memset(¤t->thread.vscr, 0, sizeof(current->thread.vscr)); current->thread.vscr.u[3] = 0x00010000; /* Java mode disabled */ current->thread.vrsave = 0; current->thread.used_vr = 0; #endif /* CONFIG_ALTIVEC */ #ifdef CONFIG_SPE memset(current->thread.evr, 0, sizeof(current->thread.evr)); current->thread.acc = 0; current->thread.spefscr = 0; current->thread.used_spe = 0; #endif /* CONFIG_SPE */ } #define PR_FP_ALL_EXCEPT (PR_FP_EXC_DIV | PR_FP_EXC_OVF | PR_FP_EXC_UND \ | PR_FP_EXC_RES | PR_FP_EXC_INV) int set_fpexc_mode(struct task_struct *tsk, unsigned int val) { struct pt_regs *regs = tsk->thread.regs; /* This is a bit hairy. If we are an SPE enabled processor * (have embedded fp) we store the IEEE exception enable flags in * fpexc_mode. fpexc_mode is also used for setting FP exception * mode (asyn, precise, disabled) for 'Classic' FP. */ if (val & PR_FP_EXC_SW_ENABLE) { #ifdef CONFIG_SPE if (cpu_has_feature(CPU_FTR_SPE)) { tsk->thread.fpexc_mode = val & (PR_FP_EXC_SW_ENABLE | PR_FP_ALL_EXCEPT); return 0; } else { return -EINVAL; } #else return -EINVAL; #endif } /* on a CONFIG_SPE this does not hurt us. The bits that * __pack_fe01 use do not overlap with bits used for * PR_FP_EXC_SW_ENABLE. Additionally, the MSR[FE0,FE1] bits * on CONFIG_SPE implementations are reserved so writing to * them does not change anything */ if (val > PR_FP_EXC_PRECISE) return -EINVAL; tsk->thread.fpexc_mode = __pack_fe01(val); if (regs != NULL && (regs->msr & MSR_FP) != 0) regs->msr = (regs->msr & ~(MSR_FE0|MSR_FE1)) | tsk->thread.fpexc_mode; return 0; } int get_fpexc_mode(struct task_struct *tsk, unsigned long adr) { unsigned int val; if (tsk->thread.fpexc_mode & PR_FP_EXC_SW_ENABLE) #ifdef CONFIG_SPE if (cpu_has_feature(CPU_FTR_SPE)) val = tsk->thread.fpexc_mode; else return -EINVAL; #else return -EINVAL; #endif else val = __unpack_fe01(tsk->thread.fpexc_mode); return put_user(val, (unsigned int __user *) adr); } int set_endian(struct task_struct *tsk, unsigned int val) { struct pt_regs *regs = tsk->thread.regs; if ((val == PR_ENDIAN_LITTLE && !cpu_has_feature(CPU_FTR_REAL_LE)) || (val == PR_ENDIAN_PPC_LITTLE && !cpu_has_feature(CPU_FTR_PPC_LE))) return -EINVAL; if (regs == NULL) return -EINVAL; if (val == PR_ENDIAN_BIG) regs->msr &= ~MSR_LE; else if (val == PR_ENDIAN_LITTLE || val == PR_ENDIAN_PPC_LITTLE) regs->msr |= MSR_LE; else return -EINVAL; return 0; } int get_endian(struct task_struct *tsk, unsigned long adr) { struct pt_regs *regs = tsk->thread.regs; unsigned int val; if (!cpu_has_feature(CPU_FTR_PPC_LE) && !cpu_has_feature(CPU_FTR_REAL_LE)) return -EINVAL; if (regs == NULL) return -EINVAL; if (regs->msr & MSR_LE) { if (cpu_has_feature(CPU_FTR_REAL_LE)) val = PR_ENDIAN_LITTLE; else val = PR_ENDIAN_PPC_LITTLE; } else val = PR_ENDIAN_BIG; return put_user(val, (unsigned int __user *)adr); } int set_unalign_ctl(struct task_struct *tsk, unsigned int val) { tsk->thread.align_ctl = val; return 0; } int get_unalign_ctl(struct task_struct *tsk, unsigned long adr) { return put_user(tsk->thread.align_ctl, (unsigned int __user *)adr); } #define TRUNC_PTR(x) ((typeof(x))(((unsigned long)(x)) & 0xffffffff)) int sys_clone(unsigned long clone_flags, unsigned long usp, int __user *parent_tidp, void __user *child_threadptr, int __user *child_tidp, int p6, struct pt_regs *regs) { CHECK_FULL_REGS(regs); if (usp == 0) usp = regs->gpr[1]; /* stack pointer for child */ #ifdef CONFIG_PPC64 if (test_thread_flag(TIF_32BIT)) { parent_tidp = TRUNC_PTR(parent_tidp); child_tidp = TRUNC_PTR(child_tidp); } #endif return do_fork(clone_flags, usp, regs, 0, parent_tidp, child_tidp); } int sys_fork(unsigned long p1, unsigned long p2, unsigned long p3, unsigned long p4, unsigned long p5, unsigned long p6, struct pt_regs *regs) { CHECK_FULL_REGS(regs); return do_fork(SIGCHLD, regs->gpr[1], regs, 0, NULL, NULL); } int sys_vfork(unsigned long p1, unsigned long p2, unsigned long p3, unsigned long p4, unsigned long p5, unsigned long p6, struct pt_regs *regs) { CHECK_FULL_REGS(regs); return do_fork(CLONE_VFORK | CLONE_VM | SIGCHLD, regs->gpr[1], regs, 0, NULL, NULL); } int sys_execve(unsigned long a0, unsigned long a1, unsigned long a2, unsigned long a3, unsigned long a4, unsigned long a5, struct pt_regs *regs) { int error; char *filename; filename = getname((char __user *) a0); error = PTR_ERR(filename); if (IS_ERR(filename)) goto out; flush_fp_to_thread(current); flush_altivec_to_thread(current); flush_spe_to_thread(current); error = do_execve(filename, (char __user * __user *) a1, (char __user * __user *) a2, regs); putname(filename); out: return error; } #ifdef CONFIG_IRQSTACKS static inline int valid_irq_stack(unsigned long sp, struct task_struct *p, unsigned long nbytes) { unsigned long stack_page; unsigned long cpu = task_cpu(p); /* * Avoid crashing if the stack has overflowed and corrupted * task_cpu(p), which is in the thread_info struct. */ if (cpu < NR_CPUS && cpu_possible(cpu)) { stack_page = (unsigned long) hardirq_ctx[cpu]; if (sp >= stack_page + sizeof(struct thread_struct) && sp <= stack_page + THREAD_SIZE - nbytes) return 1; stack_page = (unsigned long) softirq_ctx[cpu]; if (sp >= stack_page + sizeof(struct thread_struct) && sp <= stack_page + THREAD_SIZE - nbytes) return 1; } return 0; } #else #define valid_irq_stack(sp, p, nb) 0 #endif /* CONFIG_IRQSTACKS */ int validate_sp(unsigned long sp, struct task_struct *p, unsigned long nbytes) { unsigned long stack_page = (unsigned long)task_stack_page(p); if (sp >= stack_page + sizeof(struct thread_struct) && sp <= stack_page + THREAD_SIZE - nbytes) return 1; return valid_irq_stack(sp, p, nbytes); } EXPORT_SYMBOL(validate_sp); unsigned long get_wchan(struct task_struct *p) { unsigned long ip, sp; int count = 0; if (!p || p == current || p->state == TASK_RUNNING) return 0; sp = p->thread.ksp; if (!validate_sp(sp, p, STACK_FRAME_OVERHEAD)) return 0; do { sp = *(unsigned long *)sp; if (!validate_sp(sp, p, STACK_FRAME_OVERHEAD)) return 0; if (count > 0) { ip = ((unsigned long *)sp)[STACK_FRAME_LR_SAVE]; if (!in_sched_functions(ip)) return ip; } } while (count++ < 16); return 0; } static int kstack_depth_to_print = 64; void show_stack(struct task_struct *tsk, unsigned long *stack) { unsigned long sp, ip, lr, newsp; int count = 0; int firstframe = 1; sp = (unsigned long) stack; if (tsk == NULL) tsk = current; if (sp == 0) { if (tsk == current) asm("mr %0,1" : "=r" (sp)); else sp = tsk->thread.ksp; } lr = 0; printk("Call Trace:\n"); do { if (!validate_sp(sp, tsk, STACK_FRAME_OVERHEAD)) return; stack = (unsigned long *) sp; newsp = stack[0]; ip = stack[STACK_FRAME_LR_SAVE]; if (!firstframe || ip != lr) { printk("["REG"] ["REG"] ", sp, ip); print_symbol("%s", ip); if (firstframe) printk(" (unreliable)"); printk("\n"); } firstframe = 0; /* * See if this is an exception frame. * We look for the "regshere" marker in the current frame. */ if (validate_sp(sp, tsk, STACK_INT_FRAME_SIZE) && stack[STACK_FRAME_MARKER] == STACK_FRAME_REGS_MARKER) { struct pt_regs *regs = (struct pt_regs *) (sp + STACK_FRAME_OVERHEAD); printk("--- Exception: %lx", regs->trap); print_symbol(" at %s\n", regs->nip); lr = regs->link; print_symbol(" LR = %s\n", lr); firstframe = 1; } sp = newsp; } while (count++ < kstack_depth_to_print); } void dump_stack(void) { show_stack(current, NULL); } EXPORT_SYMBOL(dump_stack); #ifdef CONFIG_PPC64 void ppc64_runlatch_on(void) { unsigned long ctrl; if (cpu_has_feature(CPU_FTR_CTRL) && !test_thread_flag(TIF_RUNLATCH)) { HMT_medium(); ctrl = mfspr(SPRN_CTRLF); ctrl |= CTRL_RUNLATCH; mtspr(SPRN_CTRLT, ctrl); set_thread_flag(TIF_RUNLATCH); } } void ppc64_runlatch_off(void) { unsigned long ctrl; if (cpu_has_feature(CPU_FTR_CTRL) && test_thread_flag(TIF_RUNLATCH)) { HMT_medium(); clear_thread_flag(TIF_RUNLATCH); ctrl = mfspr(SPRN_CTRLF); ctrl &= ~CTRL_RUNLATCH; mtspr(SPRN_CTRLT, ctrl); } } #endif #if THREAD_SHIFT < PAGE_SHIFT static struct kmem_cache *thread_info_cache; struct thread_info *alloc_thread_info(struct task_struct *tsk) { struct thread_info *ti; ti = kmem_cache_alloc(thread_info_cache, GFP_KERNEL); if (unlikely(ti == NULL)) return NULL; #ifdef CONFIG_DEBUG_STACK_USAGE memset(ti, 0, THREAD_SIZE); #endif return ti; } void free_thread_info(struct thread_info *ti) { kmem_cache_free(thread_info_cache, ti); } void thread_info_cache_init(void) { thread_info_cache = kmem_cache_create("thread_info", THREAD_SIZE, THREAD_SIZE, 0, NULL); BUG_ON(thread_info_cache == NULL); } #endif /* THREAD_SHIFT < PAGE_SHIFT */