From f09630bff51daaf427968c61c0f2370c64148e06 Mon Sep 17 00:00:00 2001 From: Robin Getz Date: Sat, 26 Jul 2008 19:45:46 +0800 Subject: Blackfin arch: Add unwinding for stack info, and a little more detail on trace buffer Signed-off-by: Robin Getz Signed-off-by: Bryan Wu --- arch/blackfin/kernel/traps.c | 296 +++++++++++++++++++++++++++++++++++-------- 1 file changed, 241 insertions(+), 55 deletions(-) (limited to 'arch/blackfin') diff --git a/arch/blackfin/kernel/traps.c b/arch/blackfin/kernel/traps.c index f061f51..ad922ab 100644 --- a/arch/blackfin/kernel/traps.c +++ b/arch/blackfin/kernel/traps.c @@ -69,8 +69,6 @@ void __init trap_init(void) unsigned long saved_icplb_fault_addr, saved_dcplb_fault_addr; -int kstack_depth_to_print = 48; - static void decode_address(char *buf, unsigned long address) { struct vm_list_struct *vml; @@ -163,6 +161,9 @@ static void decode_address(char *buf, unsigned long address) if (!in_atomic) mmput(mm); + if (!strlen(buf)) + sprintf(buf, "<0x%p> [ %s ] dynamic memory", (void *)address, name); + goto done; } @@ -173,7 +174,7 @@ static void decode_address(char *buf, unsigned long address) } /* we were unable to find this address anywhere */ - sprintf(buf, "<0x%p> /* unknown address */", (void *)address); + sprintf(buf, "<0x%p> /* kernel dynamic memory */", (void *)address); done: write_unlock_irqrestore(&tasklist_lock, flags); @@ -494,7 +495,7 @@ asmlinkage void trap_c(struct pt_regs *fp) BUG_ON(sig == 0); if (sig != SIGTRAP) { - unsigned long stack; + unsigned long *stack; dump_bfin_process(fp); dump_bfin_mem(fp); show_regs(fp); @@ -508,14 +509,23 @@ asmlinkage void trap_c(struct pt_regs *fp) else #endif dump_bfin_trace_buffer(); - show_stack(current, &stack); + if (oops_in_progress) { + /* Dump the current kernel stack */ + printk(KERN_NOTICE "\n" KERN_NOTICE "Kernel Stack\n"); + show_stack(current, NULL); + print_modules(); #ifndef CONFIG_ACCESS_CHECK printk(KERN_EMERG "Please turn on " "CONFIG_ACCESS_CHECK\n"); #endif panic("Kernel exception"); + } else { + /* Dump the user space stack */ + stack = (unsigned long *)rdusp(); + printk(KERN_NOTICE "Userspace Stack\n"); + show_stack(NULL, stack); } } @@ -532,11 +542,71 @@ asmlinkage void trap_c(struct pt_regs *fp) #define EXPAND_LEN ((1 << CONFIG_DEBUG_BFIN_HWTRACE_EXPAND_LEN) * 256 - 1) +/* + * Similar to get_user, do some address checking, then dereference + * Return true on sucess, false on bad address + */ +bool get_instruction(unsigned short *val, unsigned short *address) +{ + + unsigned long addr; + + addr = (unsigned long)address; + + /* Check for odd addresses */ + if (addr & 0x1) + return false; + + /* Check that things do not wrap around */ + if (addr > (addr + 2)) + return false; + + /* + * Since we are in exception context, we need to do a little address checking + * We need to make sure we are only accessing valid memory, and + * we don't read something in the async space that can hang forever + */ + if ((addr >= FIXED_CODE_START && (addr + 2) <= physical_mem_end) || +#ifdef L2_START + (addr >= L2_START && (addr + 2) <= (L2_START + L2_LENGTH)) || +#endif + (addr >= BOOT_ROM_START && (addr + 2) <= (BOOT_ROM_START + BOOT_ROM_LENGTH)) || +#if L1_DATA_A_LENGTH != 0 + (addr >= L1_DATA_A_START && (addr + 2) <= (L1_DATA_A_START + L1_DATA_A_LENGTH)) || +#endif +#if L1_DATA_B_LENGTH != 0 + (addr >= L1_DATA_B_START && (addr + 2) <= (L1_DATA_B_START + L1_DATA_B_LENGTH)) || +#endif + (addr >= L1_SCRATCH_START && (addr + 2) <= (L1_SCRATCH_START + L1_SCRATCH_LENGTH)) || + (!(bfin_read_EBIU_AMBCTL0() & B0RDYEN) && + addr >= ASYNC_BANK0_BASE && (addr + 2) <= (ASYNC_BANK0_BASE + ASYNC_BANK0_SIZE)) || + (!(bfin_read_EBIU_AMBCTL0() & B1RDYEN) && + addr >= ASYNC_BANK1_BASE && (addr + 2) <= (ASYNC_BANK1_BASE + ASYNC_BANK1_SIZE)) || + (!(bfin_read_EBIU_AMBCTL1() & B2RDYEN) && + addr >= ASYNC_BANK2_BASE && (addr + 2) <= (ASYNC_BANK2_BASE + ASYNC_BANK1_SIZE)) || + (!(bfin_read_EBIU_AMBCTL1() & B3RDYEN) && + addr >= ASYNC_BANK3_BASE && (addr + 2) <= (ASYNC_BANK3_BASE + ASYNC_BANK1_SIZE))) { + *val = *address; + return true; + } + +#if L1_CODE_LENGTH != 0 + if (addr >= L1_CODE_START && (addr + 2) <= (L1_CODE_START + L1_CODE_LENGTH)) { + dma_memcpy(val, address, 2); + return true; + } +#endif + + + return false; +} + void dump_bfin_trace_buffer(void) { #ifdef CONFIG_DEBUG_BFIN_HWTRACE_ON int tflags, i = 0; char buf[150]; + unsigned short val = 0, *addr; #ifdef CONFIG_DEBUG_BFIN_HWTRACE_EXPAND int j, index; #endif @@ -549,8 +619,42 @@ void dump_bfin_trace_buffer(void) for (; bfin_read_TBUFSTAT() & TBUFCNT; i++) { decode_address(buf, (unsigned long)bfin_read_TBUF()); printk(KERN_NOTICE "%4i Target : %s\n", i, buf); - decode_address(buf, (unsigned long)bfin_read_TBUF()); - printk(KERN_NOTICE " Source : %s\n", buf); + addr = (unsigned short *)bfin_read_TBUF(); + decode_address(buf, (unsigned long)addr); + printk(KERN_NOTICE " Source : %s ", buf); + if (get_instruction(&val, addr)) { + if (val == 0x0010) + printk("RTS"); + else if (val == 0x0011) + printk("RTI"); + else if (val == 0x0012) + printk("RTX"); + else if (val >= 0x0050 && val <= 0x0057) + printk("JUMP (P%i)", val & 7); + else if (val >= 0x0060 && val <= 0x0067) + printk("CALL (P%i)", val & 7); + else if (val >= 0x0070 && val <= 0x0077) + printk("CALL (PC+P%i)", val & 7); + else if (val >= 0x0080 && val <= 0x0087) + printk("JUMP (PC+P%i)", val & 7); + else if ((val >= 0x1000 && val <= 0x13FF) || + (val >= 0x1800 && val <= 0x1BFF)) + printk("IF !CC JUMP"); + else if ((val >= 0x1400 && val <= 0x17ff) || + (val >= 0x1c00 && val <= 0x1fff)) + printk("IF CC JUMP"); + else if (val >= 0x2000 && val <= 0x2fff) + printk("JUMP.S"); + else if (val >= 0xe080 && val <= 0xe0ff) + printk("LSETUP"); + else if (val >= 0xe200 && val <= 0xe2ff) + printk("JUMP.L"); + else if (val >= 0xe300 && val <= 0xe3ff) + printk("CALL pcrel"); + else + printk("0x%04x", val); + } + printk("\n"); } } @@ -582,59 +686,151 @@ void dump_bfin_trace_buffer(void) } EXPORT_SYMBOL(dump_bfin_trace_buffer); -static void show_trace(struct task_struct *tsk, unsigned long *sp) +/* + * Checks to see if the address pointed to is either a + * 16-bit CALL instruction, or a 32-bit CALL instruction + */ +bool is_bfin_call(unsigned short *addr) { - unsigned long addr; + unsigned short opcode = 0, *ins_addr; + ins_addr = (unsigned short *)addr; - printk(KERN_NOTICE "\n" KERN_NOTICE "Call Trace:\n"); - - while (!kstack_end(sp)) { - addr = *sp++; - /* - * If the address is either in the text segment of the - * kernel, or in the region which contains vmalloc'ed - * memory, it *may* be the address of a calling - * routine; if so, print it so that someone tracing - * down the cause of the crash will be able to figure - * out the call path that was taken. - */ - if (kernel_text_address(addr)) - print_ip_sym(addr); - } + if (!get_instruction(&opcode, ins_addr)) + return false; - printk(KERN_NOTICE "\n"); -} + if ((opcode >= 0x0060 && opcode <= 0x0067) || + (opcode >= 0x0070 && opcode <= 0x0077)) + return true; + + ins_addr--; + if (!get_instruction(&opcode, ins_addr)) + return false; + if (opcode >= 0xE300 && opcode <= 0xE3FF) + return true; + + return false; + +} void show_stack(struct task_struct *task, unsigned long *stack) { - unsigned long *endstack, addr; - int i; + unsigned int *addr, *endstack, *fp = 0, *frame; + unsigned short *ins_addr; + char buf[150]; + unsigned int i, j, ret_addr, frame_no = 0; - /* Cannot call dump_bfin_trace_buffer() here as show_stack() is - * called externally in some places in the kernel. + /* + * If we have been passed a specific stack, use that one otherwise + * if we have been passed a task structure, use that, otherwise + * use the stack of where the variable "stack" exists */ - if (!stack) { - if (task) + if (stack == NULL) { + if (task) { + /* We know this is a kernel stack, so this is the start/end */ stack = (unsigned long *)task->thread.ksp; - else + endstack = (unsigned int *)(((unsigned int)(stack) & ~(THREAD_SIZE - 1)) + THREAD_SIZE); + } else { + /* print out the existing stack info */ stack = (unsigned long *)&stack; + endstack = (unsigned int *)PAGE_ALIGN((unsigned int)stack); + } + } else + endstack = (unsigned int *)PAGE_ALIGN((unsigned int)stack); + + decode_address(buf, (unsigned int)stack); + printk(KERN_NOTICE "Stack info:\n" KERN_NOTICE " SP: [0x%p] %s\n", stack, buf); + addr = (unsigned int *)((unsigned int)stack & ~0x3F); + + /* First thing is to look for a frame pointer */ + for (addr = (unsigned int *)((unsigned int)stack & ~0xF), i = 0; + addr < endstack; addr++, i++) { + if (*addr & 0x1) + continue; + ins_addr = (unsigned short *)*addr; + ins_addr--; + if (is_bfin_call(ins_addr)) + fp = addr - 1; + + if (fp) { + /* Let's check to see if it is a frame pointer */ + while (fp >= (addr - 1) && fp < endstack && fp) + fp = (unsigned int *)*fp; + if (fp == 0 || fp == endstack) { + fp = addr - 1; + break; + } + fp = 0; + } } + if (fp) { + frame = fp; + printk(" FP: (0x%p)\n", fp); + } else + frame = 0; - addr = (unsigned long)stack; - endstack = (unsigned long *)PAGE_ALIGN(addr); + /* + * Now that we think we know where things are, we + * walk the stack again, this time printing things out + * incase there is no frame pointer, we still look for + * valid return addresses + */ - printk(KERN_NOTICE "Stack from %08lx:", (unsigned long)stack); - for (i = 0; i < kstack_depth_to_print; i++) { - if (stack + 1 > endstack) - break; - if (i % 8 == 0) - printk("\n" KERN_NOTICE " "); - printk(" %08lx", *stack++); + /* First time print out data, next time, print out symbols */ + for (j = 0; j <= 1; j++) { + if (j) + printk(KERN_NOTICE "Return addresses in stack:\n"); + else + printk(KERN_NOTICE " Memory from 0x%08lx to %p", ((long unsigned int)stack & ~0xF), endstack); + + fp = frame; + frame_no = 0; + + for (addr = (unsigned int *)((unsigned int)stack & ~0xF), i = 0; + addr <= endstack; addr++, i++) { + + ret_addr = 0; + if (!j && i % 8 == 0) + printk("\n" KERN_NOTICE "%p:",addr); + + /* if it is an odd address, or zero, just skip it */ + if (*addr & 0x1 || !*addr) + goto print; + + ins_addr = (unsigned short *)*addr; + + /* Go back one instruction, and see if it is a CALL */ + ins_addr--; + ret_addr = is_bfin_call(ins_addr); + print: + if (!j && stack == (unsigned long *)addr) + printk("[%08x]", *addr); + else if (ret_addr) + if (j) { + decode_address(buf, (unsigned int)*addr); + if (frame == addr) { + printk(KERN_NOTICE " frame %2i : %s\n", frame_no, buf); + continue; + } + printk(KERN_NOTICE " address : %s\n", buf); + } else + printk("<%08x>", *addr); + else if (fp == addr) { + if (j) + frame = addr+1; + else + printk("(%08x)", *addr); + + fp = (unsigned int *)*addr; + frame_no++; + + } else if (!j) + printk(" %08x ", *addr); + } + if (!j) + printk("\n"); } - printk("\n"); - show_trace(task, stack); } void dump_stack(void) @@ -715,19 +911,9 @@ void dump_bfin_mem(struct pt_regs *fp) if (!((unsigned long)addr & 0xF)) printk("\n" KERN_NOTICE "0x%p: ", addr); - if (get_user(val, addr)) { - if (addr >= (unsigned short *)L1_CODE_START && - addr < (unsigned short *)(L1_CODE_START + L1_CODE_LENGTH)) { - dma_memcpy(&val, addr, sizeof(val)); - sprintf(buf, "%04x", val); - } else if (addr >= (unsigned short *)FIXED_CODE_START && - addr <= (unsigned short *)memory_start) { - val = bfin_read16(addr); - sprintf(buf, "%04x", val); - } else { + if (get_instruction(&val, addr)) { val = 0; sprintf(buf, "????"); - } } else sprintf(buf, "%04x", val); -- cgit v1.1