From 623b0355d5b1f9c6d05005b649a2f3a7b9fd7816 Mon Sep 17 00:00:00 2001 From: Haavard Skinnemoen Date: Tue, 13 Mar 2007 17:59:11 +0100 Subject: [PATCH] [AVR32] Clean up exception handling code * Use generic BUG() handling * Remove some useless debug statements * Use a common function _exception() to send signals or oops when an exception can't be handled. This makes sure init doesn't enter an infinite exception loop as well. Borrowed from powerpc. * Add some basic exception tracing support to the page fault code. * Rework dump_stack(), show_regs() and friends and move everything into process.c * Print information about configuration options and chip type when oopsing Signed-off-by: Haavard Skinnemoen --- arch/avr32/Kconfig | 5 + arch/avr32/kernel/module.c | 11 +- arch/avr32/kernel/process.c | 188 ++++++++++++++++-- arch/avr32/kernel/traps.c | 421 ++++++++++++---------------------------- arch/avr32/kernel/vmlinux.lds.c | 9 +- arch/avr32/mm/fault.c | 116 ++++------- include/asm-avr32/bug.h | 50 +++-- include/asm-avr32/processor.h | 6 +- include/asm-avr32/system.h | 13 +- 9 files changed, 402 insertions(+), 417 deletions(-) diff --git a/arch/avr32/Kconfig b/arch/avr32/Kconfig index 257b836..7a1eb44 100644 --- a/arch/avr32/Kconfig +++ b/arch/avr32/Kconfig @@ -68,6 +68,11 @@ config GENERIC_CALIBRATE_DELAY bool default y +config GENERIC_BUG + bool + default y + depends on BUG + source "init/Kconfig" menu "System Type and features" diff --git a/arch/avr32/kernel/module.c b/arch/avr32/kernel/module.c index b599eae..1167fe9c 100644 --- a/arch/avr32/kernel/module.c +++ b/arch/avr32/kernel/module.c @@ -12,10 +12,11 @@ * published by the Free Software Foundation. */ -#include -#include -#include +#include #include +#include +#include +#include #include void *module_alloc(unsigned long size) @@ -315,10 +316,10 @@ int module_finalize(const Elf_Ehdr *hdr, const Elf_Shdr *sechdrs, vfree(module->arch.syminfo); module->arch.syminfo = NULL; - return 0; + return module_bug_finalize(hdr, sechdrs, module); } void module_arch_cleanup(struct module *module) { - + module_bug_cleanup(module); } diff --git a/arch/avr32/kernel/process.c b/arch/avr32/kernel/process.c index 4f8d2d47..4e4181e 100644 --- a/arch/avr32/kernel/process.c +++ b/arch/avr32/kernel/process.c @@ -11,6 +11,7 @@ #include #include #include +#include #include #include @@ -115,39 +116,178 @@ void release_thread(struct task_struct *dead_task) /* do nothing */ } +static void dump_mem(const char *str, const char *log_lvl, + unsigned long bottom, unsigned long top) +{ + unsigned long p; + int i; + + printk("%s%s(0x%08lx to 0x%08lx)\n", log_lvl, str, bottom, top); + + for (p = bottom & ~31; p < top; ) { + printk("%s%04lx: ", log_lvl, p & 0xffff); + + for (i = 0; i < 8; i++, p += 4) { + unsigned int val; + + if (p < bottom || p >= top) + printk(" "); + else { + if (__get_user(val, (unsigned int __user *)p)) { + printk("\n"); + goto out; + } + printk("%08x ", val); + } + } + printk("\n"); + } + +out: + return; +} + +static inline int valid_stack_ptr(struct thread_info *tinfo, unsigned long p) +{ + return (p > (unsigned long)tinfo) + && (p < (unsigned long)tinfo + THREAD_SIZE - 3); +} + +#ifdef CONFIG_FRAME_POINTER +static void show_trace_log_lvl(struct task_struct *tsk, unsigned long *sp, + struct pt_regs *regs, const char *log_lvl) +{ + unsigned long lr, fp; + struct thread_info *tinfo; + + if (regs) + fp = regs->r7; + else if (tsk == current) + asm("mov %0, r7" : "=r"(fp)); + else + fp = tsk->thread.cpu_context.r7; + + /* + * Walk the stack as long as the frame pointer (a) is within + * the kernel stack of the task, and (b) it doesn't move + * downwards. + */ + tinfo = task_thread_info(tsk); + printk("%sCall trace:\n", log_lvl); + while (valid_stack_ptr(tinfo, fp)) { + unsigned long new_fp; + + lr = *(unsigned long *)fp; +#ifdef CONFIG_KALLSYMS + printk("%s [<%08lx>] ", log_lvl, lr); +#else + printk(" [<%08lx>] ", lr); +#endif + print_symbol("%s\n", lr); + + new_fp = *(unsigned long *)(fp + 4); + if (new_fp <= fp) + break; + fp = new_fp; + } + printk("\n"); +} +#else +static void show_trace_log_lvl(struct task_struct *tsk, unsigned long *sp, + struct pt_regs *regs, const char *log_lvl) +{ + unsigned long addr; + + printk("%sCall trace:\n", log_lvl); + + while (!kstack_end(sp)) { + addr = *sp++; + if (kernel_text_address(addr)) { +#ifdef CONFIG_KALLSYMS + printk("%s [<%08lx>] ", log_lvl, addr); +#else + printk(" [<%08lx>] ", addr); +#endif + print_symbol("%s\n", addr); + } + } + printk("\n"); +} +#endif + +void show_stack_log_lvl(struct task_struct *tsk, unsigned long sp, + struct pt_regs *regs, const char *log_lvl) +{ + struct thread_info *tinfo; + + if (sp == 0) { + if (tsk) + sp = tsk->thread.cpu_context.ksp; + else + sp = (unsigned long)&tinfo; + } + if (!tsk) + tsk = current; + + tinfo = task_thread_info(tsk); + + if (valid_stack_ptr(tinfo, sp)) { + dump_mem("Stack: ", log_lvl, sp, + THREAD_SIZE + (unsigned long)tinfo); + show_trace_log_lvl(tsk, (unsigned long *)sp, regs, log_lvl); + } +} + +void show_stack(struct task_struct *tsk, unsigned long *stack) +{ + show_stack_log_lvl(tsk, (unsigned long)stack, NULL, ""); +} + +void dump_stack(void) +{ + unsigned long stack; + + show_trace_log_lvl(current, &stack, NULL, ""); +} +EXPORT_SYMBOL(dump_stack); + static const char *cpu_modes[] = { "Application", "Supervisor", "Interrupt level 0", "Interrupt level 1", "Interrupt level 2", "Interrupt level 3", "Exception", "NMI" }; -void show_regs(struct pt_regs *regs) +void show_regs_log_lvl(struct pt_regs *regs, const char *log_lvl) { unsigned long sp = regs->sp; unsigned long lr = regs->lr; unsigned long mode = (regs->sr & MODE_MASK) >> MODE_SHIFT; - if (!user_mode(regs)) + if (!user_mode(regs)) { sp = (unsigned long)regs + FRAME_SIZE_FULL; - print_symbol("PC is at %s\n", instruction_pointer(regs)); - print_symbol("LR is at %s\n", lr); - printk("pc : [<%08lx>] lr : [<%08lx>] %s\n" - "sp : %08lx r12: %08lx r11: %08lx\n", - instruction_pointer(regs), - lr, print_tainted(), sp, regs->r12, regs->r11); - printk("r10: %08lx r9 : %08lx r8 : %08lx\n", - regs->r10, regs->r9, regs->r8); - printk("r7 : %08lx r6 : %08lx r5 : %08lx r4 : %08lx\n", - regs->r7, regs->r6, regs->r5, regs->r4); - printk("r3 : %08lx r2 : %08lx r1 : %08lx r0 : %08lx\n", - regs->r3, regs->r2, regs->r1, regs->r0); - printk("Flags: %c%c%c%c%c\n", + printk("%s", log_lvl); + print_symbol("PC is at %s\n", instruction_pointer(regs)); + printk("%s", log_lvl); + print_symbol("LR is at %s\n", lr); + } + + printk("%spc : [<%08lx>] lr : [<%08lx>] %s\n" + "%ssp : %08lx r12: %08lx r11: %08lx\n", + log_lvl, instruction_pointer(regs), lr, print_tainted(), + log_lvl, sp, regs->r12, regs->r11); + printk("%sr10: %08lx r9 : %08lx r8 : %08lx\n", + log_lvl, regs->r10, regs->r9, regs->r8); + printk("%sr7 : %08lx r6 : %08lx r5 : %08lx r4 : %08lx\n", + log_lvl, regs->r7, regs->r6, regs->r5, regs->r4); + printk("%sr3 : %08lx r2 : %08lx r1 : %08lx r0 : %08lx\n", + log_lvl, regs->r3, regs->r2, regs->r1, regs->r0); + printk("%sFlags: %c%c%c%c%c\n", log_lvl, regs->sr & SR_Q ? 'Q' : 'q', regs->sr & SR_V ? 'V' : 'v', regs->sr & SR_N ? 'N' : 'n', regs->sr & SR_Z ? 'Z' : 'z', regs->sr & SR_C ? 'C' : 'c'); - printk("Mode bits: %c%c%c%c%c%c%c%c%c\n", + printk("%sMode bits: %c%c%c%c%c%c%c%c%c\n", log_lvl, regs->sr & SR_H ? 'H' : 'h', regs->sr & SR_R ? 'R' : 'r', regs->sr & SR_J ? 'J' : 'j', @@ -157,9 +297,21 @@ void show_regs(struct pt_regs *regs) regs->sr & SR_I1M ? '1' : '.', regs->sr & SR_I0M ? '0' : '.', regs->sr & SR_GM ? 'G' : 'g'); - printk("CPU Mode: %s\n", cpu_modes[mode]); + printk("%sCPU Mode: %s\n", log_lvl, cpu_modes[mode]); + printk("%sProcess: %s [%d] (task: %p thread: %p)\n", + log_lvl, current->comm, current->pid, current, + task_thread_info(current)); +} + +void show_regs(struct pt_regs *regs) +{ + unsigned long sp = regs->sp; + + if (!user_mode(regs)) + sp = (unsigned long)regs + FRAME_SIZE_FULL; - show_trace(NULL, (unsigned long *)sp, regs); + show_regs_log_lvl(regs, ""); + show_trace_log_lvl(current, (unsigned long *)sp, regs, ""); } EXPORT_SYMBOL(show_regs); diff --git a/arch/avr32/kernel/traps.c b/arch/avr32/kernel/traps.c index adc01a1..4f0382d 100644 --- a/arch/avr32/kernel/traps.c +++ b/arch/avr32/kernel/traps.c @@ -5,158 +5,25 @@ * it under the terms of the GNU General Public License version 2 as * published by the Free Software Foundation. */ -#undef DEBUG -#include + +#include #include -#include #include +#include #include +#include +#include -#include -#include #include -#include #include -#include - -static void dump_mem(const char *str, unsigned long bottom, unsigned long top) -{ - unsigned long p; - int i; - - printk("%s(0x%08lx to 0x%08lx)\n", str, bottom, top); - - for (p = bottom & ~31; p < top; ) { - printk("%04lx: ", p & 0xffff); - - for (i = 0; i < 8; i++, p += 4) { - unsigned int val; - - if (p < bottom || p >= top) - printk(" "); - else { - if (__get_user(val, (unsigned int __user *)p)) { - printk("\n"); - goto out; - } - printk("%08x ", val); - } - } - printk("\n"); - } - -out: - return; -} - -static inline int valid_stack_ptr(struct thread_info *tinfo, unsigned long p) -{ - return (p > (unsigned long)tinfo) - && (p < (unsigned long)tinfo + THREAD_SIZE - 3); -} - -#ifdef CONFIG_FRAME_POINTER -static inline void __show_trace(struct task_struct *tsk, unsigned long *sp, - struct pt_regs *regs) -{ - unsigned long lr, fp; - struct thread_info *tinfo; - - tinfo = (struct thread_info *) - ((unsigned long)sp & ~(THREAD_SIZE - 1)); - - if (regs) - fp = regs->r7; - else if (tsk == current) - asm("mov %0, r7" : "=r"(fp)); - else - fp = tsk->thread.cpu_context.r7; - - /* - * Walk the stack as long as the frame pointer (a) is within - * the kernel stack of the task, and (b) it doesn't move - * downwards. - */ - while (valid_stack_ptr(tinfo, fp)) { - unsigned long new_fp; - - lr = *(unsigned long *)fp; - printk(" [<%08lx>] ", lr); - print_symbol("%s\n", lr); - - new_fp = *(unsigned long *)(fp + 4); - if (new_fp <= fp) - break; - fp = new_fp; - } - printk("\n"); -} -#else -static inline void __show_trace(struct task_struct *tsk, unsigned long *sp, - struct pt_regs *regs) -{ - unsigned long addr; - - while (!kstack_end(sp)) { - addr = *sp++; - if (kernel_text_address(addr)) { - printk(" [<%08lx>] ", addr); - print_symbol("%s\n", addr); - } - } -} -#endif - -void show_trace(struct task_struct *tsk, unsigned long *sp, - struct pt_regs *regs) -{ - if (regs && - (((regs->sr & MODE_MASK) == MODE_EXCEPTION) || - ((regs->sr & MODE_MASK) == MODE_USER))) - return; - - printk ("Call trace:"); -#ifdef CONFIG_KALLSYMS - printk("\n"); -#endif - - __show_trace(tsk, sp, regs); - printk("\n"); -} - -void show_stack(struct task_struct *tsk, unsigned long *sp) -{ - unsigned long stack; - - if (!tsk) - tsk = current; - if (sp == 0) { - if (tsk == current) { - register unsigned long *real_sp __asm__("sp"); - sp = real_sp; - } else { - sp = (unsigned long *)tsk->thread.cpu_context.ksp; - } - } - - stack = (unsigned long)sp; - dump_mem("Stack: ", stack, - THREAD_SIZE + (unsigned long)tsk->thread_info); - show_trace(tsk, sp, NULL); -} - -void dump_stack(void) -{ - show_stack(NULL, NULL); -} -EXPORT_SYMBOL(dump_stack); +#include +#include +#include ATOMIC_NOTIFIER_HEAD(avr32_die_chain); int register_die_notifier(struct notifier_block *nb) { - pr_debug("register_die_notifier: %p\n", nb); - return atomic_notifier_chain_register(&avr32_die_chain, nb); } EXPORT_SYMBOL(register_die_notifier); @@ -169,93 +36,103 @@ EXPORT_SYMBOL(unregister_die_notifier); static DEFINE_SPINLOCK(die_lock); -void __die(const char *str, struct pt_regs *regs, unsigned long err, - const char *file, const char *func, unsigned long line) +void NORET_TYPE die(const char *str, struct pt_regs *regs, long err) { - struct task_struct *tsk = current; static int die_counter; console_verbose(); spin_lock_irq(&die_lock); bust_spinlocks(1); - printk(KERN_ALERT "%s", str); - if (file && func) - printk(" in %s:%s, line %ld", file, func, line); - printk("[#%d]:\n", ++die_counter); - print_modules(); - show_regs(regs); - printk("Process %s (pid: %d, stack limit = 0x%p)\n", - tsk->comm, tsk->pid, tsk->thread_info + 1); - - if (!user_mode(regs) || in_interrupt()) { - dump_mem("Stack: ", regs->sp, - THREAD_SIZE + (unsigned long)tsk->thread_info); + printk(KERN_ALERT "Oops: %s, sig: %ld [#%d]\n" KERN_EMERG, + str, err, ++die_counter); +#ifdef CONFIG_PREEMPT + printk("PREEMPT "); +#endif +#ifdef CONFIG_FRAME_POINTER + printk("FRAME_POINTER "); +#endif + if (current_cpu_data.features & AVR32_FEATURE_OCD) { + unsigned long did = __mfdr(DBGREG_DID); + printk("chip: 0x%03lx:0x%04lx rev %lu\n", + (did >> 1) & 0x7ff, + (did >> 12) & 0x7fff, + (did >> 28) & 0xf); + } else { + printk("cpu: arch %u r%u / core %u r%u\n", + current_cpu_data.arch_type, + current_cpu_data.arch_revision, + current_cpu_data.cpu_type, + current_cpu_data.cpu_revision); } + print_modules(); + show_regs_log_lvl(regs, KERN_EMERG); + show_stack_log_lvl(current, regs->sp, regs, KERN_EMERG); bust_spinlocks(0); spin_unlock_irq(&die_lock); - do_exit(SIGSEGV); + + if (in_interrupt()) + panic("Fatal exception in interrupt"); + + if (panic_on_oops) + panic("Fatal exception"); + + do_exit(err); } -void __die_if_kernel(const char *str, struct pt_regs *regs, unsigned long err, - const char *file, const char *func, unsigned long line) +void _exception(long signr, struct pt_regs *regs, int code, + unsigned long addr) { + siginfo_t info; + if (!user_mode(regs)) - __die(str, regs, err, file, func, line); -} + die("Unhandled exception in kernel mode", regs, signr); + + memset(&info, 0, sizeof(info)); + info.si_signo = signr; + info.si_code = code; + info.si_addr = (void __user *)addr; + force_sig_info(signr, &info, current); -asmlinkage void do_nmi(unsigned long ecr, struct pt_regs *regs) -{ -#ifdef CONFIG_SUBARCH_AVR32B /* - * The exception entry always saves RSR_EX. For NMI, this is - * wrong; it should be RSR_NMI + * Init gets no signals that it doesn't have a handler for. + * That's all very well, but if it has caused a synchronous + * exception and we ignore the resulting signal, it will just + * generate the same exception over and over again and we get + * nowhere. Better to kill it and let the kernel panic. */ - regs->sr = sysreg_read(RSR_NMI); -#endif + if (is_init(current)) { + __sighandler_t handler; + + spin_lock_irq(¤t->sighand->siglock); + handler = current->sighand->action[signr-1].sa.sa_handler; + spin_unlock_irq(¤t->sighand->siglock); + if (handler == SIG_DFL) { + /* init has generated a synchronous exception + and it doesn't have a handler for the signal */ + printk(KERN_CRIT "init has generated signal %ld " + "but has no handler for it\n", signr); + do_exit(signr); + } + } +} - printk("NMI taken!!!!\n"); - die("NMI", regs, ecr); - BUG(); +asmlinkage void do_nmi(unsigned long ecr, struct pt_regs *regs) +{ + printk(KERN_ALERT "Got Non-Maskable Interrupt, dumping regs\n"); + show_regs_log_lvl(regs, KERN_ALERT); + show_stack_log_lvl(current, regs->sp, regs, KERN_ALERT); } asmlinkage void do_critical_exception(unsigned long ecr, struct pt_regs *regs) { - printk("Unable to handle critical exception %lu at pc = %08lx!\n", - ecr, regs->pc); - die("Oops", regs, ecr); - BUG(); + die("Critical exception", regs, SIGKILL); } asmlinkage void do_address_exception(unsigned long ecr, struct pt_regs *regs) { - siginfo_t info; - - die_if_kernel("Oops: Address exception in kernel mode", regs, ecr); - -#ifdef DEBUG - if (ecr == ECR_ADDR_ALIGN_X) - pr_debug("Instruction Address Exception at pc = %08lx\n", - regs->pc); - else if (ecr == ECR_ADDR_ALIGN_R) - pr_debug("Data Address Exception (Read) at pc = %08lx\n", - regs->pc); - else if (ecr == ECR_ADDR_ALIGN_W) - pr_debug("Data Address Exception (Write) at pc = %08lx\n", - regs->pc); - else - BUG(); - - show_regs(regs); -#endif - - info.si_signo = SIGBUS; - info.si_errno = 0; - info.si_code = BUS_ADRALN; - info.si_addr = (void __user *)regs->pc; - - force_sig_info(SIGBUS, &info, current); + _exception(SIGBUS, regs, BUS_ADRALN, regs->pc); } /* This way of handling undefined instructions is stolen from ARM */ @@ -280,7 +157,8 @@ static int do_cop_absent(u32 insn) { int cop_nr; u32 cpucr; - if ( (insn & 0xfdf00000) == 0xf1900000 ) + + if ((insn & 0xfdf00000) == 0xf1900000) /* LDC0 */ cop_nr = 0; else @@ -292,136 +170,91 @@ static int do_cop_absent(u32 insn) sysreg_write(CPUCR, cpucr); cpucr = sysreg_read(CPUCR); - if ( !(cpucr & (1 << (24 + cop_nr))) ){ - printk("Coprocessor #%i not found!\n", cop_nr); - return -1; - } + if (!(cpucr & (1 << (24 + cop_nr)))) + return -ENODEV; return 0; } -#ifdef CONFIG_BUG -#ifdef CONFIG_DEBUG_BUGVERBOSE -static inline void do_bug_verbose(struct pt_regs *regs, u32 insn) -{ - char *file; - u16 line; - char c; - - if (__get_user(line, (u16 __user *)(regs->pc + 2))) - return; - if (__get_user(file, (char * __user *)(regs->pc + 4)) - || (unsigned long)file < PAGE_OFFSET - || __get_user(c, file)) - file = ""; - - printk(KERN_ALERT "kernel BUG at %s:%d!\n", file, line); -} -#else -static inline void do_bug_verbose(struct pt_regs *regs, u32 insn) +int is_valid_bugaddr(unsigned long pc) { + unsigned short opcode; + + if (pc < PAGE_OFFSET) + return 0; + if (probe_kernel_address((u16 *)pc, opcode)) + return 0; + return opcode == AVR32_BUG_OPCODE; } -#endif -#endif asmlinkage void do_illegal_opcode(unsigned long ecr, struct pt_regs *regs) { u32 insn; struct undef_hook *hook; - siginfo_t info; void __user *pc; + long code; - if (!user_mode(regs)) - goto kernel_trap; + if (!user_mode(regs) && (ecr == ECR_ILLEGAL_OPCODE)) { + enum bug_trap_type type; + + type = report_bug(regs->pc); + switch (type) { + case BUG_TRAP_TYPE_NONE: + break; + case BUG_TRAP_TYPE_WARN: + regs->pc += 2; + return; + case BUG_TRAP_TYPE_BUG: + die("Kernel BUG", regs, SIGKILL); + } + } local_irq_enable(); - pc = (void __user *)instruction_pointer(regs); - if (__get_user(insn, (u32 __user *)pc)) - goto invalid_area; + if (user_mode(regs)) { + pc = (void __user *)instruction_pointer(regs); + if (get_user(insn, (u32 __user *)pc)) + goto invalid_area; - if (ecr == ECR_COPROC_ABSENT) { - if (do_cop_absent(insn) == 0) + if (ecr == ECR_COPROC_ABSENT && !do_cop_absent(insn)) return; - } - spin_lock_irq(&undef_lock); - list_for_each_entry(hook, &undef_hook, node) { - if ((insn & hook->insn_mask) == hook->insn_val) { - if (hook->fn(regs, insn) == 0) { - spin_unlock_irq(&undef_lock); - return; + spin_lock_irq(&undef_lock); + list_for_each_entry(hook, &undef_hook, node) { + if ((insn & hook->insn_mask) == hook->insn_val) { + if (hook->fn(regs, insn) == 0) { + spin_unlock_irq(&undef_lock); + return; + } } } + spin_unlock_irq(&undef_lock); } - spin_unlock_irq(&undef_lock); - -invalid_area: -#ifdef DEBUG - printk("Illegal instruction at pc = %08lx\n", regs->pc); - if (regs->pc < TASK_SIZE) { - unsigned long ptbr, pgd, pte, *p; - - ptbr = sysreg_read(PTBR); - p = (unsigned long *)ptbr; - pgd = p[regs->pc >> 22]; - p = (unsigned long *)((pgd & 0x1ffff000) | 0x80000000); - pte = p[(regs->pc >> 12) & 0x3ff]; - printk("page table: 0x%08lx -> 0x%08lx -> 0x%08lx\n", ptbr, pgd, pte); - } -#endif - - info.si_signo = SIGILL; - info.si_errno = 0; - info.si_addr = (void __user *)regs->pc; switch (ecr) { - case ECR_ILLEGAL_OPCODE: - case ECR_UNIMPL_INSTRUCTION: - info.si_code = ILL_ILLOPC; - break; case ECR_PRIVILEGE_VIOLATION: - info.si_code = ILL_PRVOPC; + code = ILL_PRVOPC; break; case ECR_COPROC_ABSENT: - info.si_code = ILL_COPROC; + code = ILL_COPROC; break; default: - BUG(); + code = ILL_ILLOPC; + break; } - force_sig_info(SIGILL, &info, current); + _exception(SIGILL, regs, code, regs->pc); return; -kernel_trap: -#ifdef CONFIG_BUG - if (__kernel_text_address(instruction_pointer(regs))) { - insn = *(u16 *)instruction_pointer(regs); - if (insn == AVR32_BUG_OPCODE) { - do_bug_verbose(regs, insn); - die("Kernel BUG", regs, 0); - return; - } - } -#endif - - die("Oops: Illegal instruction in kernel code", regs, ecr); +invalid_area: + _exception(SIGSEGV, regs, SEGV_MAPERR, regs->pc); } asmlinkage void do_fpe(unsigned long ecr, struct pt_regs *regs) { - siginfo_t info; - - printk("Floating-point exception at pc = %08lx\n", regs->pc); - - /* We have no FPU... */ - info.si_signo = SIGILL; - info.si_errno = 0; - info.si_addr = (void __user *)regs->pc; - info.si_code = ILL_COPROC; - - force_sig_info(SIGILL, &info, current); + /* We have no FPU yet */ + _exception(SIGILL, regs, ILL_COPROC, regs->pc); } diff --git a/arch/avr32/kernel/vmlinux.lds.c b/arch/avr32/kernel/vmlinux.lds.c index ef13b7c7..7ad20cf 100644 --- a/arch/avr32/kernel/vmlinux.lds.c +++ b/arch/avr32/kernel/vmlinux.lds.c @@ -26,6 +26,12 @@ SECTIONS _sinittext = .; *(.text.reset) *(.init.text) + /* + * .exit.text is discarded at runtime, not + * link time, to deal with references from + * __bug_table + */ + *(.exit.text) _einittext = .; . = ALIGN(4); __tagtable_begin = .; @@ -86,6 +92,8 @@ SECTIONS __stop___ex_table = .; } + BUG_TABLE + RODATA . = ALIGN(8192); @@ -126,7 +134,6 @@ SECTIONS * thrown away, as cleanup code is never called unless it's a module. */ /DISCARD/ : { - *(.exit.text) *(.exit.data) *(.exitcall.exit) } diff --git a/arch/avr32/mm/fault.c b/arch/avr32/mm/fault.c index 6785572..146ebdb 100644 --- a/arch/avr32/mm/fault.c +++ b/arch/avr32/mm/fault.c @@ -16,26 +16,8 @@ #include #include #include -#include #include - -#ifdef DEBUG -static void dump_code(unsigned long pc) -{ - char *p = (char *)pc; - char val; - int i; - - - printk(KERN_DEBUG "Code:"); - for (i = 0; i < 16; i++) { - if (__get_user(val, p + i)) - break; - printk(" %02x", val); - } - printk("\n"); -} -#endif +#include #ifdef CONFIG_KPROBES ATOMIC_NOTIFIER_HEAD(notify_page_fault_chain); @@ -68,17 +50,19 @@ static inline int notify_page_fault(enum die_val val, struct pt_regs *regs, } #endif +int exception_trace = 1; + /* * This routine handles page faults. It determines the address and the * problem, and then passes it off to one of the appropriate routines. * * ecr is the Exception Cause Register. Possible values are: - * 5: Page not found (instruction access) * 6: Protection fault (instruction access) - * 12: Page not found (read access) - * 13: Page not found (write access) - * 14: Protection fault (read access) - * 15: Protection fault (write access) + * 15: Protection fault (read access) + * 16: Protection fault (write access) + * 20: Page not found (instruction access) + * 24: Page not found (read access) + * 28: Page not found (write access) */ asmlinkage void do_page_fault(unsigned long ecr, struct pt_regs *regs) { @@ -88,7 +72,9 @@ asmlinkage void do_page_fault(unsigned long ecr, struct pt_regs *regs) const struct exception_table_entry *fixup; unsigned long address; unsigned long page; - int writeaccess = 0; + int writeaccess; + long signr; + int code; if (notify_page_fault(DIE_PAGE_FAULT, regs, ecr, SIGSEGV) == NOTIFY_STOP) @@ -99,6 +85,9 @@ asmlinkage void do_page_fault(unsigned long ecr, struct pt_regs *regs) tsk = current; mm = tsk->mm; + signr = SIGSEGV; + code = SEGV_MAPERR; + /* * If we're in an interrupt or have no user context, we must * not take the fault... @@ -125,7 +114,9 @@ asmlinkage void do_page_fault(unsigned long ecr, struct pt_regs *regs) * can handle it... */ good_area: - //pr_debug("good area: vm_flags = 0x%lx\n", vma->vm_flags); + code = SEGV_ACCERR; + writeaccess = 0; + switch (ecr) { case ECR_PROTECTION_X: case ECR_TLB_MISS_X: @@ -176,46 +167,24 @@ survive: * map. Fix it, but check if it's kernel or user first... */ bad_area: - pr_debug("Bad area [%s:%u]: addr %08lx, ecr %lu\n", - tsk->comm, tsk->pid, address, ecr); - up_read(&mm->mmap_sem); if (user_mode(regs)) { - /* Hmm...we have to pass address and ecr somehow... */ - /* tsk->thread.address = address; - tsk->thread.error_code = ecr; */ -#ifdef DEBUG - show_regs(regs); - dump_code(regs->pc); - - page = sysreg_read(PTBR); - printk("ptbr = %08lx", page); - if (page) { - page = ((unsigned long *)page)[address >> 22]; - printk(" pgd = %08lx", page); - if (page & _PAGE_PRESENT) { - page &= PAGE_MASK; - address &= 0x003ff000; - page = ((unsigned long *)__va(page))[address >> PAGE_SHIFT]; - printk(" pte = %08lx\n", page); - } - } -#endif - pr_debug("Sending SIGSEGV to PID %d...\n", - tsk->pid); - force_sig(SIGSEGV, tsk); + if (exception_trace) + printk("%s%s[%d]: segfault at %08lx pc %08lx " + "sp %08lx ecr %lu\n", + is_init(tsk) ? KERN_EMERG : KERN_INFO, + tsk->comm, tsk->pid, address, regs->pc, + regs->sp, ecr); + _exception(SIGSEGV, regs, code, address); return; } no_context: - pr_debug("No context\n"); - /* Are we prepared to handle this kernel fault? */ fixup = search_exception_tables(regs->pc); if (fixup) { regs->pc = fixup->fixup; - pr_debug("Found fixup at %08lx\n", fixup->fixup); return; } @@ -230,7 +199,6 @@ no_context: printk(KERN_ALERT "Unable to handle kernel paging request"); printk(" at virtual address %08lx\n", address); - printk(KERN_ALERT "pc = %08lx\n", regs->pc); page = sysreg_read(PTBR); printk(KERN_ALERT "ptbr = %08lx", page); @@ -241,20 +209,20 @@ no_context: page &= PAGE_MASK; address &= 0x003ff000; page = ((unsigned long *)__va(page))[address >> PAGE_SHIFT]; - printk(" pte = %08lx\n", page); + printk(" pte = %08lx", page); } } - die("\nOops", regs, ecr); - do_exit(SIGKILL); + printk("\n"); + die("Kernel access of bad area", regs, signr); + return; /* * We ran out of memory, or some other thing happened to us * that made us unable to handle the page fault gracefully. */ out_of_memory: - printk("Out of memory\n"); up_read(&mm->mmap_sem); - if (current->pid == 1) { + if (is_init(current)) { yield(); down_read(&mm->mmap_sem); goto survive; @@ -267,21 +235,20 @@ out_of_memory: do_sigbus: up_read(&mm->mmap_sem); - /* - * Send a sigbus, regardless of whether we were in kernel or - * user mode. - */ - /* address, error_code, trap_no, ... */ -#ifdef DEBUG - show_regs(regs); - dump_code(regs->pc); -#endif - pr_debug("Sending SIGBUS to PID %d...\n", tsk->pid); - force_sig(SIGBUS, tsk); - /* Kernel mode? Handle exceptions or die */ + signr = SIGBUS; + code = BUS_ADRERR; if (!user_mode(regs)) goto no_context; + + if (exception_trace) + printk("%s%s[%d]: bus error at %08lx pc %08lx " + "sp %08lx ecr %lu\n", + is_init(tsk) ? KERN_EMERG : KERN_INFO, + tsk->comm, tsk->pid, address, regs->pc, + regs->sp, ecr); + + _exception(SIGBUS, regs, BUS_ADRERR, address); } asmlinkage void do_bus_error(unsigned long addr, int write_access, @@ -292,8 +259,7 @@ asmlinkage void do_bus_error(unsigned long addr, int write_access, addr, write_access ? "write" : "read"); printk(KERN_INFO "DTLB dump:\n"); dump_dtlb(); - die("Bus Error", regs, write_access); - do_exit(SIGKILL); + die("Bus Error", regs, SIGKILL); } /* diff --git a/include/asm-avr32/bug.h b/include/asm-avr32/bug.h index 521766b..afdcd79 100644 --- a/include/asm-avr32/bug.h +++ b/include/asm-avr32/bug.h @@ -18,27 +18,53 @@ #ifdef CONFIG_DEBUG_BUGVERBOSE -#define BUG() \ - do { \ - asm volatile(".hword %0\n\t" \ - ".hword %1\n\t" \ - ".long %2" \ - : \ - : "n"(AVR32_BUG_OPCODE), \ - "i"(__LINE__), "X"(__FILE__)); \ - } while (0) +#define _BUG_OR_WARN(flags) \ + asm volatile( \ + "1: .hword %0\n" \ + " .section __bug_table,\"a\",@progbits\n" \ + "2: .long 1b\n" \ + " .long %1\n" \ + " .short %2\n" \ + " .short %3\n" \ + " .org 2b + %4\n" \ + " .previous" \ + : \ + : "i"(AVR32_BUG_OPCODE), "i"(__FILE__), \ + "i"(__LINE__), "i"(flags), \ + "i"(sizeof(struct bug_entry))) #else +#define _BUG_OR_WARN(flags) \ + asm volatile( \ + "1: .hword %0\n" \ + " .section __bug_table,\"a\",@progbits\n" \ + "2: .long 1b\n" \ + " .short %1\n" \ + " .org 2b + %2\n" \ + " .previous" \ + : \ + : "i"(AVR32_BUG_OPCODE), "i"(flags), \ + "i"(sizeof(struct bug_entry))) + +#endif /* CONFIG_DEBUG_BUGVERBOSE */ + #define BUG() \ do { \ - asm volatile(".hword %0\n\t" \ - : : "n"(AVR32_BUG_OPCODE)); \ + _BUG_OR_WARN(0); \ + for (;;); \ } while (0) -#endif /* CONFIG_DEBUG_BUGVERBOSE */ +#define WARN_ON(condition) \ + ({ \ + typeof(condition) __ret_warn_on = (condition); \ + if (unlikely(__ret_warn_on)) \ + _BUG_OR_WARN(BUGFLAG_WARNING); \ + unlikely(__ret_warn_on); \ + }) #define HAVE_ARCH_BUG +#define HAVE_ARCH_WARN_ON #endif /* CONFIG_BUG */ diff --git a/include/asm-avr32/processor.h b/include/asm-avr32/processor.h index cbb89cc..6a64833 100644 --- a/include/asm-avr32/processor.h +++ b/include/asm-avr32/processor.h @@ -134,10 +134,10 @@ extern int kernel_thread(int (*fn)(void *), void *arg, unsigned long flags); #define thread_saved_pc(tsk) ((tsk)->thread.cpu_context.pc) struct pt_regs; -void show_trace(struct task_struct *task, unsigned long *stack, - struct pt_regs *regs); - extern unsigned long get_wchan(struct task_struct *p); +extern void show_regs_log_lvl(struct pt_regs *regs, const char *log_lvl); +extern void show_stack_log_lvl(struct task_struct *tsk, unsigned long sp, + struct pt_regs *regs, const char *log_lvl); #define KSTK_EIP(tsk) ((tsk)->thread.cpu_context.pc) #define KSTK_ESP(tsk) ((tsk)->thread.cpu_context.ksp) diff --git a/include/asm-avr32/system.h b/include/asm-avr32/system.h index ac596058..a8236ba 100644 --- a/include/asm-avr32/system.h +++ b/include/asm-avr32/system.h @@ -9,6 +9,7 @@ #define __ASM_AVR32_SYSTEM_H #include +#include #include #include @@ -140,15 +141,9 @@ static inline unsigned long __cmpxchg(volatile void *ptr, unsigned long old, sizeof(*(ptr)))) struct pt_regs; -extern void __die(const char *, struct pt_regs *, unsigned long, - const char *, const char *, unsigned long); -extern void __die_if_kernel(const char *, struct pt_regs *, unsigned long, - const char *, const char *, unsigned long); - -#define die(msg, regs, err) \ - __die(msg, regs, err, __FILE__ ":", __FUNCTION__, __LINE__) -#define die_if_kernel(msg, regs, err) \ - __die_if_kernel(msg, regs, err, __FILE__ ":", __FUNCTION__, __LINE__) +void NORET_TYPE die(const char *str, struct pt_regs *regs, long err); +void _exception(long signr, struct pt_regs *regs, int code, + unsigned long addr); #define arch_align_stack(x) (x) -- 2.7.4